seperate rand instances for each thread
[carveJwlIkooP6JGAAIwe30JlM.git] / player_skate.c
index b2d951e9026e07bccd3beed2b716deb454914a5f..7f4bc37f741991deb72b99cca2495cfe0a2731af 100644 (file)
@@ -2,23 +2,50 @@
 #define PLAYER_SKATE_C
 
 #include "player.h"
+#include "audio.h"
+#include "vg/vg_perlin.h"
+#include "menu.h"
+#include "ent_skateshop.h"
+#include "addon.h"
+
+static void player__skate_bind(void){
+   struct skeleton *sk = &localplayer.skeleton;
+   rb_update_transform( &localplayer.rb );
+
+   struct { struct skeleton_anim **anim; const char *name; }
+   bindings[] = {
+      { &player_skate.anim_grind,        "pose_grind" },
+      { &player_skate.anim_grind_jump,   "pose_grind_jump" },
+      { &player_skate.anim_stand,        "pose_stand" },
+      { &player_skate.anim_highg,        "pose_highg" },
+      { &player_skate.anim_air,          "pose_air" },
+      { &player_skate.anim_slide,        "pose_slide" },
+      { &player_skate.anim_push,         "push" },
+      { &player_skate.anim_push_reverse, "push_reverse" },
+      { &player_skate.anim_ollie,        "ollie" },
+      { &player_skate.anim_ollie_reverse,"ollie_reverse" },
+      { &player_skate.anim_grabs,        "grabs" }
+   };
 
-VG_STATIC void player__skate_bind( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-   struct player_avatar *av = player->playeravatar;
-   struct skeleton *sk = &av->sk;
-
-   rb_update_transform( &player->rb );
-   s->anim_stand           = skeleton_get_anim( sk, "pose_stand" );
-   s->anim_highg           = skeleton_get_anim( sk, "pose_highg" );
-   s->anim_air             = skeleton_get_anim( sk, "pose_air" );
-   s->anim_slide           = skeleton_get_anim( sk, "pose_slide" );
-   s->anim_push            = skeleton_get_anim( sk, "push" );
-   s->anim_push_reverse    = skeleton_get_anim( sk, "push_reverse" );
-   s->anim_ollie           = skeleton_get_anim( sk, "ollie" );
-   s->anim_ollie_reverse   = skeleton_get_anim( sk, "ollie_reverse" );
-   s->anim_grabs           = skeleton_get_anim( sk, "grabs" );
+   for( u32 i=0; i<vg_list_size(bindings); i++ )
+      *bindings[i].anim = skeleton_get_anim( sk, bindings[i].name );
+}
+
+static void player__skate_kill_audio(void){
+   audio_lock();
+   if( player_skate.aud_main ){
+      player_skate.aud_main = 
+         audio_channel_fadeout( player_skate.aud_main, 0.1f );
+   }
+   if( player_skate.aud_air ){
+      player_skate.aud_air = 
+         audio_channel_fadeout( player_skate.aud_air, 0.1f );
+   }
+   if( player_skate.aud_slide ){
+      player_skate.aud_slide = 
+         audio_channel_fadeout( player_skate.aud_slide, 0.1f );
+   }
+   audio_unlock();
 }
 
 /* 
@@ -31,28 +58,24 @@ VG_STATIC void player__skate_bind( player_instance *player )
  * Does collision detection on a sphere vs world, and applies some smoothing
  * filters to the manifold afterwards
  */
-VG_STATIC int skate_collide_smooth( player_instance *player,
-                                    m4x3f mtx, rb_sphere *sphere,
-                                    rb_ct *man )
-{
-   debug_sphere( mtx, sphere->radius, VG__BLACK );
+static int skate_collide_smooth( m4x3f mtx, rb_sphere *sphere, rb_ct *man ){
+   world_instance *world = world_current_instance();
 
    int len = 0;
-   len = rb_sphere__scene( mtx, sphere, NULL, &world.rb_geo.inf.scene, man );
+   len = rb_sphere__scene( mtx, sphere, NULL, &world->rb_geo.inf.scene, man,
+                           k_material_flag_walking );
 
-   for( int i=0; i<len; i++ )
-   {
-      man[i].rba = &player->rb;
+   for( int i=0; i<len; i++ ){
+      man[i].rba = &localplayer.rb;
       man[i].rbb = NULL;
    }
 
-   rb_manifold_filter_coplanar( man, len, 0.05f );
+   rb_manifold_filter_coplanar( man, len, 0.03f );
 
-   if( len > 1 )
-   {
+   if( len > 1 ){
       rb_manifold_filter_backface( man, len );
-      rb_manifold_filter_joint_edges( man, len, 0.05f );
-      rb_manifold_filter_pairs( man, len, 0.05f );
+      rb_manifold_filter_joint_edges( man, len, 0.03f );
+      rb_manifold_filter_pairs( man, len, 0.03f );
    }
    int new_len = rb_manifold_apply_filtered( man, len );
    if( len && !new_len )
@@ -62,763 +85,774 @@ VG_STATIC int skate_collide_smooth( player_instance *player,
 
    return len;
 }
-/*
- * Gets the closest grindable edge to the player within max_dist 
- */
-VG_STATIC struct grind_edge *skate_collect_grind_edge( v3f p0, v3f p1,
-                                                       v3f c0, v3f c1, 
-                                                       float max_dist )
+
+struct grind_info
 {
-   bh_iter it;
-   bh_iter_init( 0, &it );
+   v3f co, dir, n;
+};
+
+static int skate_grind_scansq( v3f pos, v3f dir, float r,
+                                  struct grind_info *inf ){
+   world_instance *world = world_current_instance();
+
+   v4f plane;
+   v3_copy( dir, plane );
+   v3_normalize( plane );
+   plane[3] = v3_dot( plane, pos );
+
+   boxf box;
+   v3_add( pos, (v3f){ r, r, r }, box[1] );
+   v3_sub( pos, (v3f){ r, r, r }, box[0] );
+
+   struct grind_sample{
+      v2f co;
+      v2f normal;
+      v3f normal3,
+          centroid;
+   }
+   samples[48];
+   int sample_count = 0;
 
-   boxf region;
+   v2f support_min,
+       support_max;
 
-   box_init_inf( region );
-   box_addpt( region, p0 );
-   box_addpt( region, p1 );
+   v3f support_axis;
+   v3_cross( plane, (v3f){0,1,0}, support_axis );
+   v3_normalize( support_axis );
    
-   float k_r = max_dist;
-   v3_add( (v3f){ k_r, k_r, k_r}, region[1], region[1] );
-   v3_add( (v3f){-k_r,-k_r,-k_r}, region[0], region[0] );
-
-   float closest = k_r*k_r;
-   struct grind_edge *closest_edge = NULL;
+   bh_iter it;
+   bh_iter_init_box( 0, &it, box );
+   i32 idx;
    
-   int idx;
-   while( bh_next( world.grind_bh, &it, region, &idx ) )
-   {
-      struct grind_edge *edge = &world.grind_edges[ idx ];
+   while( bh_next( world->geo_bh, &it, &idx ) ){
+      u32 *ptri = &world->scene_geo.arrindices[ idx*3 ];
+      v3f tri[3];
 
-      float s,t;
-      v3f pa, pb;
+      struct world_surface *surf = world_tri_index_surface(world,ptri[0]);
+      if( !(surf->info.flags & k_material_flag_grindable) )
+         continue;
 
-      float d2 = 
-         closest_segment_segment( p0, p1, edge->p0, edge->p1, &s,&t, pa, pb );
+      for( int j=0; j<3; j++ )
+         v3_copy( world->scene_geo.arrvertices[ptri[j]].co, tri[j] );
 
-      if( d2 < closest )
-      {
-         closest = d2;
-         closest_edge = edge;
-         v3_copy( pa, c0 );
-         v3_copy( pb, c1 );
-      }
-   }
+      for( int j=0; j<3; j++ ){
+         int i0 = j,
+             i1 = (j+1) % 3;
+         
+         struct grind_sample *sample = &samples[ sample_count ];
+         v3f co;
 
-   return closest_edge;
-}
+         if( plane_segment( plane, tri[i0], tri[i1], co ) ){
+            v3f d;
+            v3_sub( co, pos, d );
+            if( v3_length2( d ) > r*r )
+               continue;
 
-VG_STATIC int skate_grind_collide( player_instance *player, rb_ct *contact )
-{
-   v3f p0, p1, c0, c1;
-   v3_muladds( player->rb.co, player->rb.to_world[2],  0.5f, p0 );
-   v3_muladds( player->rb.co, player->rb.to_world[2], -0.5f, p1 );
-   v3_muladds( p0, player->rb.to_world[1], 0.08f, p0 );
-   v3_muladds( p1, player->rb.to_world[1], 0.08f, p1 );
+            v3f va, vb, normal;
+            v3_sub( tri[1], tri[0], va );
+            v3_sub( tri[2], tri[0], vb );
+            v3_cross( va, vb, normal );
 
-   float const k_r = 0.25f;
-   struct grind_edge *closest_edge = skate_collect_grind_edge( p0, p1, 
-                                                               c0, c1, k_r );
+            sample->normal[0] = v3_dot( support_axis, normal );
+            sample->normal[1] = normal[1];
+            sample->co[0]     = v3_dot( support_axis, d );
+            sample->co[1]     = d[1];
 
-   if( closest_edge )
-   {
-      v3f delta;
-      v3_sub( c1, c0, delta );
+            v3_copy( normal, sample->normal3 ); /* normalize later
+                                                   if we want to us it */
 
-      if( v3_dot( delta, player->rb.to_world[1] ) > 0.0001f )
-      {
-         contact->p = v3_length( delta );
-         contact->type = k_contact_type_edge;
-         contact->element_id = 0;
-         v3_copy( c1, contact->co );
-         contact->rba = NULL;
-         contact->rbb = NULL;
-
-         v3f edge_dir, axis_dir;
-         v3_sub( closest_edge->p1, closest_edge->p0, edge_dir );
-         v3_normalize( edge_dir );
-         v3_cross( (v3f){0.0f,1.0f,0.0f}, edge_dir, axis_dir );
-         v3_cross( edge_dir, axis_dir, contact->n );
+            v3_muls(                      tri[0], 1.0f/3.0f, sample->centroid );
+            v3_muladds( sample->centroid, tri[1], 1.0f/3.0f, sample->centroid );
+            v3_muladds( sample->centroid, tri[2], 1.0f/3.0f, sample->centroid );
 
-         return 1;
+            v2_normalize( sample->normal );
+            sample_count ++;
+
+            if( sample_count == vg_list_size( samples ) )
+               goto too_many_samples;
+         }
       }
-      else
-         return 0;
    }
 
-   return 0;
-}
+too_many_samples:
 
-/*
- *
- * Prediction system
- *
- *
- */
+   if( sample_count < 2 )
+      return 0;
 
-/* 
- * Trace a path given a velocity rotation.
- *
- * TODO: this MIGHT be worth doing RK4 on the gravity field.
- */
-VG_STATIC void skate_score_biased_path( v3f co, v3f v, m3x3f vr, 
-                                        struct land_prediction *prediction )
-{
-   float pstep  = VG_TIMESTEP_FIXED * 10.0f;
-   float k_bias = 0.96f;
+   v3f average_direction,
+       average_normal;
 
-   v3f pco, pco1, pv;
-   v3_copy( co, pco );
-   v3_muls( v,  k_bias, pv );
+   v2f min_co, max_co;
+   v2_fill( min_co,  INFINITY );
+   v2_fill( max_co, -INFINITY );
 
-   m3x3_mulv( vr, pv, pv );
-   v3_muladds( pco, pv, pstep, pco );
+   v3_zero( average_direction );
+   v3_zero( average_normal );
 
-   struct grind_edge *best_grind = NULL;
-   float closest_grind = INFINITY;
+   int passed_samples = 0;
+   
+   for( int i=0; i<sample_count-1; i++ ){
+      struct grind_sample *si, *sj;
 
-   float grind_score    = INFINITY,
-         air_score      = INFINITY,
-         time_to_impact = 0.0f;
+      si = &samples[i];
 
-   prediction->log_length = 0;
-   v3_copy( pco, prediction->apex );
+      for( int j=i+1; j<sample_count; j++ ){
+         if( i == j )
+            continue;
 
-   for( int i=0; i<vg_list_size(prediction->log); i++ )
-   {
-      v3_copy( pco, pco1 );
+         sj = &samples[j];
 
-      pv[1] += -k_gravity * pstep;
+         /* non overlapping */
+         if( v2_dist2( si->co, sj->co ) >= (0.01f*0.01f) )
+            continue;
 
-      m3x3_mulv( vr, pv, pv );
-      v3_muladds( pco, pv, pstep, pco );
+         /* not sharp angle */
+         if( v2_dot( si->normal, sj->normal ) >= 0.7f )
+            continue;
 
-      if( pco[1] > prediction->apex[1] )
-         v3_copy( pco, prediction->apex );
-      
-      v3f vdir;
+         /* not convex */
+         v3f v0;
+         v3_sub( sj->centroid, si->centroid, v0 );
+         if( v3_dot( v0, si->normal3 ) >= 0.0f ||
+             v3_dot( v0, sj->normal3 ) <= 0.0f )
+            continue;
 
-      v3_sub( pco, pco1, vdir );
+         v2_minv( sj->co, min_co, min_co );
+         v2_maxv( sj->co, max_co, max_co );
+         
+         v3f n0, n1, dir;
+         v3_copy( si->normal3, n0 );
+         v3_copy( sj->normal3, n1 );
+         v3_cross( n0, n1, dir );
 
-      float l = v3_length( vdir );
-      v3_muls( vdir, 1.0f/l, vdir );
+         if( v3_length2( dir ) <= 0.000001f )
+            continue;
 
-      v3f c0, c1;
-      struct grind_edge *ge = skate_collect_grind_edge( pco, pco1,
-                                                        c0, c1, 0.4f );
+         v3_normalize( dir );
 
-      if( ge && (v3_dot((v3f){0.0f,1.0f,0.0f},vdir) < -0.2f ) )
-      {
-         float d2 = v3_dist2( c0, c1 );
-         if( d2 < closest_grind )
-         {
-            closest_grind = d2;
-            best_grind = ge;
-            grind_score = closest_grind * 0.05f;
-         }
+         /* make sure the directions all face a common hemisphere */
+         v3_muls( dir, vg_signf(v3_dot(dir,plane)), dir );
+         v3_add( average_direction, dir, average_direction );
+
+         float yi = si->normal3[1],
+               yj = sj->normal3[1];
+
+         if( yi > yj ) v3_add( si->normal3, average_normal, average_normal );
+         else          v3_add( sj->normal3, average_normal, average_normal );
+
+         passed_samples ++;
       }
+   }
 
-      v3f n1;
+   if( !passed_samples )
+      return 0;
 
-      float t1;
-      int idx = spherecast_world( pco1, pco, 0.4f, &t1, n1 );
-      if( idx != -1 )
-      {
-         v3_copy( n1, prediction->n );
-         air_score = -v3_dot( pv, n1 );
-         
-         u32 vert_index = world.scene_geo->arrindices[ idx*3 ];
-         struct world_material *mat = world_tri_index_material( vert_index );
+   if( (v3_length2( average_direction ) <= 0.001f) ||
+       (v3_length2( average_normal ) <= 0.001f ) )
+      return 0;
 
-         /* Bias prediction towords ramps */
-         if( mat->info.flags & k_material_flag_skate_surface )
-            air_score *= 0.1f;
+   float div = 1.0f/(float)passed_samples;
+   v3_normalize( average_direction );
+   v3_normalize( average_normal );
 
-         v3_lerp( pco1, pco, t1, prediction->log[ prediction->log_length ++ ] ); 
-         time_to_impact += t1 * pstep;
-         break;
-      }
+   v2f average_coord;
+   v2_add( min_co, max_co, average_coord );
+   v2_muls( average_coord, 0.5f, average_coord );
 
-      time_to_impact += pstep;
-      v3_copy( pco, prediction->log[ prediction->log_length ++ ] );
-   }
+   v3_muls( support_axis, average_coord[0], inf->co );
+   inf->co[1] += average_coord[1];
+   v3_add( pos, inf->co, inf->co );
+   v3_copy( average_normal, inf->n );
+   v3_copy( average_direction, inf->dir );
 
-   if( grind_score < air_score )
-   {
-      prediction->score = grind_score; 
-      prediction->type = k_prediction_grind;
-   }
-   else if( air_score < INFINITY )
-   {
-      prediction->score = air_score;
-      prediction->type = k_prediction_land;
-   }
-   else
-   {
-      prediction->score = INFINITY;
-      prediction->type = k_prediction_none;
-   }
+   vg_line_point( inf->co, 0.02f, VG__GREEN );
+   vg_line_arrow( inf->co, average_direction, 0.3f, VG__GREEN );
+   vg_line_arrow( inf->co, inf->n, 0.2f, VG__CYAN );
 
-   prediction->land_dist = time_to_impact;
+   return passed_samples;
 }
 
-VG_STATIC 
-void player__approximate_best_trajectory( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+static void reset_jump_info( jump_info *inf ){
+   inf->log_length = 0;
+   inf->land_dist = 0.0f;
+   inf->score = 0.0f;
+   inf->type = k_prediction_unset;
+   v3_zero( inf->apex );
+}
 
-   float pstep = VG_TIMESTEP_FIXED * 10.0f;
-   float best_velocity_delta = -9999.9f;
+static int create_jumps_to_hit_target( jump_info *jumps,
+                                          v3f target, float max_angle_delta,
+                                          float gravity ){
+   /* calculate the exact 2 solutions to jump onto that grind spot */
 
-   v3f axis;
-   v3_cross( player->rb.to_world[1], player->rb.v, axis );
-   v3_normalize( axis );
+   v3f v0;
+   v3_sub( target, localplayer.rb.co, v0 );
 
-   s->prediction_count = 0;
-   m3x3_identity( s->state.velocity_bias );
+   v3f ax;
+   v3_copy( v0, ax );
+   ax[1] = 0.0f;
+   v3_normalize( ax );
 
-   float best_vmod   = 0.0f,
-         min_score   =  INFINITY,
-         max_score   = -INFINITY;
+   v2f d = { v3_dot( ax, v0 ),               v0[1] },
+       v = { v3_dot( ax, localplayer.rb.v ), localplayer.rb.v[1] };
 
-   v3_zero( s->state.apex );
-   s->land_dist = 0.0f;
+   float a = atan2f( v[1], v[0] ),
+         m = v2_length( v ),
+         root = m*m*m*m - gravity*(gravity*d[0]*d[0] + 2.0f*d[1]*m*m);
 
-   /*
-    * Search a broad selection of futures
-    */
-   for( int m=-3;m<=12; m++ )
-   {
-      struct land_prediction *p = &s->predictions[ s->prediction_count ++ ];
+   int valid_count = 0;
 
-      float vmod = ((float)m / 15.0f)*0.09f;
+   if( root > 0.0f ){
+      root = sqrtf( root );
+      float a0 = atanf( (m*m + root) / (gravity * d[0]) ),
+            a1 = atanf( (m*m - root) / (gravity * d[0]) );
 
-      m3x3f bias;
-      v4f bias_q;
+      if( fabsf(a0-a) < max_angle_delta ){
+         jump_info *inf = &jumps[ valid_count ++ ];
+         reset_jump_info( inf );
 
-      q_axis_angle( bias_q, axis, vmod );
-      q_m3x3( bias_q, bias );
+         v3_muls( ax, cosf( a0 ) * m, inf->v );
+         inf->v[1] += sinf( a0 ) * m;
+         inf->land_dist = d[0] / (cosf(a0)*m);
+         inf->gravity = gravity;
 
-      skate_score_biased_path( player->rb.co, player->rb.v, bias, p );
+         v3_copy( target, inf->log[inf->log_length ++] );
+      }
 
-      if( p->type != k_prediction_none )
-      {
-         if( p->score < min_score )
-         {
-            min_score = p->score;
-            best_vmod = vmod;
-            s->land_dist = p->land_dist;
-            v3_copy( p->apex, s->state.apex );
-         }
+      if( fabsf(a1-a) < max_angle_delta ){
+         jump_info *inf = &jumps[ valid_count ++ ];
+         reset_jump_info( inf );
+
+         v3_muls( ax, cosf( a1 ) * m, inf->v );
+         inf->v[1] += sinf( a1 ) * m;
+         inf->land_dist = d[0] / (cosf(a1)*m);
+         inf->gravity = gravity;
 
-         if( p->score > max_score )
-            max_score = p->score;
+         v3_copy( target, inf->log[inf->log_length ++] );
       }
    }
 
-   v4f vr_q;
-   q_axis_angle( vr_q, axis, best_vmod*0.1f );
-   q_m3x3( vr_q, s->state.velocity_bias );
+   return valid_count;
+}
 
-   q_axis_angle( vr_q, axis, best_vmod );
-   q_m3x3( vr_q, s->state.velocity_bias_pstep );
+static void player__approximate_best_trajectory(void){
+   world_instance *world0 = world_current_instance();
 
-   /*
-    * Logging
-    */
-   for( int i=0; i<s->prediction_count; i ++ )
-   {
-      struct land_prediction *p = &s->predictions[i];
+   float k_trace_delta = k_rb_delta * 10.0f;
+   struct player_skate_state *state = &player_skate.state;
 
-      float l = p->score;
+   state->air_start = vg.time;
+   v3_copy( localplayer.rb.v, state->air_init_v );
+   v3_copy( localplayer.rb.co, state->air_init_co );
 
-      if( l < 0.0f )
-      {
-         vg_error( "negative score! (%f)\n", l );
-      }
+   player_skate.possible_jump_count = 0;
 
-      l -= min_score;
-      l /= (max_score-min_score);
-      l  = 1.0f - l;
-      l *= 255.0f;
+   v3f axis;
+   v3_cross( localplayer.rb.v, localplayer.rb.to_world[1], axis );
+   v3_normalize( axis );
 
-      p->colour = l;
-      p->colour <<= 8;
-      p->colour |= 0xff000000;
-   }
+   /* at high slopes, Y component is low */
+   float upness      = localplayer.rb.to_world[1][1],
+         angle_begin = -(1.0f-fabsf( upness )),
+         angle_end   =   1.0f;
 
+   struct grind_info grind;
+   int grind_located = 0;
+   float grind_located_gravity = k_gravity;
 
-   v2f steer = { player->input_js1h->axis.value,
-                 player->input_js1v->axis.value };
-   v2_normalize_clamp( steer );
 
-   if( (fabsf(steer[1]) > 0.5f) && (s->land_dist >= 1.0f) )
-   {
-      s->state.flip_rate = (1.0f/s->land_dist) * vg_signf(steer[1]) *
-                              s->state.reverse ;
-      s->state.flip_time = 0.0f;
-      v3_copy( player->rb.to_world[0], s->state.flip_axis );
-   }
-   else
-   {
-      s->state.flip_rate = 0.0f;
-      v3_zero( s->state.flip_axis );
-   }
-}
+   v3f launch_v_bounds[2];
 
-/*
- *
- * Varius physics models
- * ------------------------------------------------
- */
+   for( int i=0; i<2; i++ ){
+      v3_copy( localplayer.rb.v, launch_v_bounds[i] );
+      float ang = (float[]){ angle_begin, angle_end }[ i ];
+            ang *= 0.15f;
 
-VG_STATIC void skate_apply_grind_model( player_instance *player,
-                                        rb_ct *manifold, int len )
-{
-   struct player_skate *s = &player->_skate;
+      v4f qbias;
+      q_axis_angle( qbias, axis, ang );
+      q_mulv( qbias, launch_v_bounds[i], launch_v_bounds[i] );
+   }
 
-   /* FIXME: Queue audio events instead */
-   if( len == 0 )
-   {
-      if( s->state.activity == k_skate_activity_grind )
-      {
-#if 0
-         audio_lock();
-         audio_player_set_flags( &audio_player_extra, 
-                                 AUDIO_FLAG_SPACIAL_3D );
-         audio_player_set_position( &audio_player_extra, player.rb.co );
-         audio_player_set_vol( &audio_player_extra, 20.0f );
-         audio_player_playclip( &audio_player_extra, &audio_board[6] );
-         audio_unlock();
-#endif
+   for( int m=0;m<=30; m++ ){
+      jump_info *inf = 
+         &player_skate.possible_jumps[ player_skate.possible_jump_count ++ ];
+      reset_jump_info( inf );
 
-         s->state.activity = k_skate_activity_air;
-      }
-      return;
-   }
+      v3f launch_co, launch_v, co0, co1;
+      v3_copy( localplayer.rb.co, launch_co );
+      v3_copy( localplayer.rb.v,  launch_v );
+      v3_copy( launch_co, co0 );
+      world_instance *trace_world = world0;
 
-   v2f steer = { player->input_js1h->axis.value,
-                 player->input_js1v->axis.value };
-   v2_normalize_clamp( steer );
+      float vt  = (float)m * (1.0f/30.0f),
+            ang = vg_lerpf( angle_begin, angle_end, vt ) * 0.15f;
 
-   s->state.steery -= steer[0] * k_steer_air * k_rb_delta;
-   s->state.steerx += steer[1] * s->state.reverse * k_steer_air * k_rb_delta;
-   
-#if 0
-   v4f rotate;
-   q_axis_angle( rotate, player->rb.to_world[0], siX );
-   q_mul( rotate, player.rb.q, player.rb.q );
-#endif
+      v4f qbias;
+      q_axis_angle( qbias, axis, ang );
+      q_mulv( qbias, launch_v, launch_v );
 
-   s->state.slip = 0.0f;
-   s->state.activity = k_skate_activity_grind;
+      float yaw_sketch = 1.0f-fabsf(upness);
 
-   /* TODO: Compression */
-   v3f up = { 0.0f, 1.0f, 0.0f };
-   float angle = v3_dot( player->rb.to_world[1], up );
+      float yaw_bias = ((float)(m%3) - 1.0f) * 0.08f * yaw_sketch;
+      q_axis_angle( qbias, localplayer.rb.to_world[1], yaw_bias );
+      q_mulv( qbias, launch_v, launch_v );
 
-   if( fabsf(angle) < 0.99f )
-   {
-      v3f axis; 
-      v3_cross( player->rb.to_world[1], up, axis );
+      float gravity_bias = vg_lerpf( 0.85f, 1.4f, vt ),
+            gravity      = k_gravity * gravity_bias;
+      inf->gravity = gravity;
+      v3_copy( launch_v, inf->v );
 
-      v4f correction;
-      q_axis_angle( correction, axis, k_rb_delta * 10.0f * acosf(angle) );
-      q_mul( correction, player->rb.q, player->rb.q );
-   }
+      for( int i=1; i<=50; i++ ){
+         float t = (float)i * k_trace_delta;
 
-   float const DOWNFORCE = -k_downforce*1.2f*VG_TIMESTEP_FIXED;
-   v3_muladds( player->rb.v, manifold->n, DOWNFORCE, player->rb.v );
-   m3x3_identity( s->state.velocity_bias );
-   m3x3_identity( s->state.velocity_bias_pstep );
+         v3_muls( launch_v, t, co1 );
+         co1[1] += -0.5f * gravity * t*t;
+         v3_add( launch_co, co1, co1 );
 
-   if( s->state.activity_prev != k_skate_activity_grind )
-   {
-      /* FIXME: Queue audio events instead */
-#if 0
-      audio_lock();
-      audio_player_set_flags( &audio_player_extra, 
-                              AUDIO_FLAG_SPACIAL_3D );
-      audio_player_set_position( &audio_player_extra, player.rb.co );
-      audio_player_set_vol( &audio_player_extra, 20.0f );
-      audio_player_playclip( &audio_player_extra, &audio_board[5] );
-      audio_unlock();
-#endif
-   }
-}
+         float launch_vy = launch_v[1];
 
-/*
- * Air control, no real physics
- */
-VG_STATIC void skate_apply_air_model( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+         int search_for_grind = 1;
+         if( grind_located ) search_for_grind = 0;
+         if( launch_vy - gravity*t > 0.0f ) search_for_grind = 0;
 
-   if( s->state.activity != k_skate_activity_air )
-      return;
+         /* REFACTOR */
 
-   if( s->state.activity_prev != k_skate_activity_air )
-      player__approximate_best_trajectory( player );
+         v3f closest={0.0f,0.0f,0.0f};
+         if( search_for_grind ){
+            if( bh_closest_point(trace_world->geo_bh,co1,closest,1.0f) != -1 ){
+               float min_dist = 0.75f;
+                     min_dist *= min_dist;
 
-   m3x3_mulv( s->state.velocity_bias, player->rb.v, player->rb.v );
-   ray_hit hit;
+               if( v3_dist2( closest, launch_co ) < min_dist )
+                  search_for_grind = 0;
 
-   /* 
-    * Prediction 
-    */
-   float pstep  = VG_TIMESTEP_FIXED * 1.0f;
-   float k_bias = 0.98f;
+               v3f bound[2];
 
-   v3f pco, pco1, pv;
-   v3_copy( player->rb.co, pco );
-   v3_muls( player->rb.v, 1.0f, pv );
-   
-   float time_to_impact = 0.0f;
-   float limiter = 1.0f;
+               for( int j=0; j<2; j++ ){
+                  v3_muls( launch_v_bounds[j], t, bound[j] );
+                  bound[j][1] += -0.5f*gravity*t*t;
+                  v3_add( launch_co, bound[j], bound[j] );
+               }
+
+               float limh = vg_minf( 2.0f, t ),
+                     minh = vg_minf( bound[0][1], bound[1][1] )-limh,
+                     maxh = vg_maxf( bound[0][1], bound[1][1] )+limh;
 
-   struct grind_edge *best_grind = NULL;
-   float closest_grind = INFINITY;
+               if( (closest[1] < minh) || (closest[1] > maxh) ){
+                  search_for_grind = 0;
+               }
+            }
+            else
+               search_for_grind = 0;
+         }
 
-   v3f target_normal = { 0.0f, 1.0f, 0.0f };
-   int has_target = 0;
+         if( search_for_grind ){
+            v3f ve;
+            v3_copy( launch_v, ve );
+            ve[1] += -gravity * t;
+
+            if( skate_grind_scansq( closest, ve, 0.5f, &grind ) ){
+               /* check alignment */
+               v2f v0 = { ve[0], ve[2] },
+                   v1 = { grind.dir[0], grind.dir[2] };
+
+               v2_normalize( v0 );
+               v2_normalize( v1 );
+
+               float a = v2_dot( v0, v1 );
+
+               float a_min = cosf( VG_PIf * 0.185f );
+               if( state->grind_cooldown )
+                  a_min = cosf( VG_PIf * 0.05f );
+
+               /* check speed */
+               if( (fabsf(v3_dot( ve, grind.dir ))>=k_grind_axel_min_vel) &&
+                   (a >= a_min) && 
+                   (fabsf(grind.dir[1]) < 0.70710678118654752f))
+               {
+                  grind_located = 1;
+                  grind_located_gravity = inf->gravity;
+               }
+            }
+         }
 
-   for( int i=0; i<250; i++ )
-   {
-      v3_copy( pco, pco1 );
-      m3x3_mulv( s->state.velocity_bias, pv, pv );
+         if( trace_world->rendering_gate ){
+            ent_gate *gate = trace_world->rendering_gate;
+            if( gate_intersect( gate, co1, co0 ) ){
+               m4x3_mulv( gate->transport, co0, co0 );
+               m4x3_mulv( gate->transport, co1, co1 );
+               m3x3_mulv( gate->transport, launch_v, launch_v);
+               m4x3_mulv( gate->transport, launch_co, launch_co );
+
+               if( gate->flags & k_ent_gate_nonlocal )
+                  trace_world = &world_static.instances[ gate->target ];
+            }
+         }
 
-      pv[1] += -k_gravity * pstep;
-      v3_muladds( pco, pv, pstep, pco );
-      
-      ray_hit contact;
-      v3f vdir;
+         float t1;
+         v3f n;
 
-      v3_sub( pco, pco1, vdir );
-      contact.dist = v3_length( vdir );
-      v3_divs( vdir, contact.dist, vdir);
+         float scan_radius = k_board_radius;
+               scan_radius *= vg_clampf( t, 0.02f, 1.0f );
 
-      v3f c0, c1;
-      struct grind_edge *ge = skate_collect_grind_edge( pco, pco1,
-                                                        c0, c1, 0.4f );
+         int idx = spherecast_world( trace_world, co0, co1, scan_radius, &t1, n,
+                                     k_material_flag_walking );
+         if( idx != -1 ){
+            v3f co;
+            v3_lerp( co0, co1, t1, co );
+            v3_copy( co, inf->log[ inf->log_length ++ ] ); 
 
-      if( ge && (v3_dot((v3f){0.0f,1.0f,0.0f},vdir) < -0.2f ) ) 
-      { 
-         vg_line( ge->p0, ge->p1, 0xff0000ff ); 
-         vg_line_cross( pco, 0xff0000ff, 0.25f );
-         has_target = 1;
-         break;
-      }
-      
-      float orig_dist = contact.dist;
-      if( ray_world( pco1, vdir, &contact ) )
-      {
-         v3_copy( contact.normal, target_normal );
-         has_target = 1;
-         time_to_impact += (contact.dist/orig_dist)*pstep;
-         vg_line_cross( contact.pos, 0xffff0000, 0.25f );
-         break;
-      }
-      time_to_impact += pstep;
-   }
+            v3_copy( n, inf->n );
+            u32 *tri = &trace_world->scene_geo.arrindices[ idx*3 ];
+            struct world_surface *surf = 
+               world_tri_index_surface( trace_world, tri[0] );
 
-   if( has_target )
-   {
-      float angle = v3_dot( player->rb.to_world[1], target_normal );
-      v3f axis; 
-      v3_cross( player->rb.to_world[1], target_normal, axis );
+            inf->type = k_prediction_land;
 
-      limiter = vg_minf( 5.0f, time_to_impact )/5.0f;
-      limiter = 1.0f-limiter;
-      limiter *= limiter;
-      limiter = 1.0f-limiter;
+            v3f ve;
+            v3_copy( launch_v, ve );
+            ve[1] += -gravity * t;
 
-      if( fabsf(angle) < 0.99f )
-      {
-         v4f correction;
-         q_axis_angle( correction, axis, 
-                        acosf(angle)*(1.0f-limiter)*2.0f*VG_TIMESTEP_FIXED );
-         q_mul( correction, player->rb.q, player->rb.q );
-      }
-   }
+            inf->score = -v3_dot( ve, inf->n );
+            inf->land_dist = t + k_trace_delta * t1;
 
-   v2f steer = { player->input_js1h->axis.value,
-                 player->input_js1v->axis.value };
-   v2_normalize_clamp( steer );
+            /* Bias prediction towords ramps */
+            if( !(surf->info.flags & k_material_flag_skate_target) )
+               inf->score *= 10.0f;
 
-   s->state.steery -= steer[0] * k_steer_air * VG_TIMESTEP_FIXED;
-   s->state.steerx += steer[1] * s->state.reverse * k_steer_air 
-                                                         * limiter * k_rb_delta;
-   s->land_dist = time_to_impact;
-   v3_copy( target_normal, s->land_normal );
-}
+            if( surf->info.flags & k_material_flag_boundary )
+               player_skate.possible_jump_count --;
 
-VG_STATIC void skate_get_board_points( player_instance *player,
-                                       v3f front, v3f back )
-{
-   v3f pos_front = {0.0f,0.0f,-k_board_length},
-       pos_back  = {0.0f,0.0f, k_board_length};
+            break;
+         }
+         
+         if( i % 3 == 0 )
+            v3_copy( co1, inf->log[ inf->log_length ++ ] ); 
+         v3_copy( co1, co0 );
+      }
 
-   m4x3_mulv( player->rb.to_world, pos_front, front );
-   m4x3_mulv( player->rb.to_world, pos_back,  back );
-}
+      if( inf->type == k_prediction_unset )
+         player_skate.possible_jump_count --;
+   }
 
-/*
- * Casts and pushes a sphere-spring model into the world
- */
-VG_STATIC int skate_simulate_spring( player_instance *player,
-                                     v3f pos )
-{
-   struct player_skate *s = &player->_skate;
+   if( grind_located ){
+      jump_info grind_jumps[2];
+      
+      int valid_count = 
+         create_jumps_to_hit_target( grind_jumps, grind.co, 
+                                     0.175f*VG_PIf, grind_located_gravity );
+
+      /* knock out original landing points in the 1m area */
+      for( u32 j=0; j<player_skate.possible_jump_count; j++ ){
+         jump_info *jump = &player_skate.possible_jumps[ j ];
+         float dist = v3_dist2( jump->log[jump->log_length-1], grind.co );
+         float descale = 1.0f-vg_minf(1.0f,dist);
+         jump->score += descale*3.0f;
+      }
 
-   float mod      = 0.7f * player->input_grab->axis.value + 0.3f,
-         spring_k = mod * k_spring_force,
-         damp_k   = mod * k_spring_dampener,
-         disp_k   = 0.4f;
+      for( int i=0; i<valid_count; i++ ){
+         jump_info *jump = &grind_jumps[i];
+         jump->type = k_prediction_grind;
 
-   v3f start, end;
-   v3_copy( pos, start );
-   v3_muladds( pos, player->rb.to_world[1], -disp_k, end );
+         v3f launch_v, launch_co, co0, co1;
 
-   float t;
-   v3f n;
-   int hit_info = spherecast_world( start, end, 0.2f, &t, n );
+         v3_copy( jump->v, launch_v );
+         v3_copy( localplayer.rb.co, launch_co );
+         
+         float t = 0.05f * jump->land_dist;
+         v3_muls( launch_v, t, co0 );
+         co0[1] += -0.5f * jump->gravity * t*t;
+         v3_add( launch_co, co0, co0 );
+
+         /* rough scan to make sure we dont collide with anything */
+         for( int j=1; j<=16; j++ ){
+            t  = (float)j*(1.0f/16.0f);
+            t *= 0.9f;
+            t += 0.05f;
+            t *= jump->land_dist;
+
+            v3_muls( launch_v, t, co1 );
+            co1[1] += -0.5f * jump->gravity * t*t;
+            v3_add( launch_co, co1, co1 );
+            
+            float t1;
+            v3f n;
+
+            int idx = spherecast_world( world0, co0,co1,
+                                        k_board_radius*0.1f, &t1, n, 
+                                        k_material_flag_walking );
+            if( idx != -1 ){
+               goto invalidated_grind;
+            }
+
+            v3_copy( co1, co0 );
+         }
 
-   if( hit_info != -1 )
-   {
-      v3f F, delta;
-      v3_sub( start, player->rb.co, delta );
-      
-      float displacement = vg_clampf( 1.0f-t, 0.0f, 1.0f ),
-            damp         = 
-         vg_maxf( 0.0f, v3_dot( player->rb.to_world[1], player->rb.v ) );
+         v3_copy( grind.n, jump->n );
 
-      v3_muls( player->rb.to_world[1], displacement*spring_k*k_rb_delta -
-                                       damp*damp_k*k_rb_delta, F );
+         /* determine score */
+         v3f ve;
+         v3_copy( jump->v, ve );
+         ve[1] += -jump->gravity*jump->land_dist;
+         jump->score = -v3_dot( ve, grind.n ) * 0.9f;
 
-      v3_muladds( player->rb.v, F, 1.0f, player->rb.v );
-      
-      /* Angular velocity */
-      v3f wa;
-      v3_cross( delta, F, wa );
-      v3_muladds( player->rb.w, wa, k_spring_angular, player->rb.w );
+         player_skate.possible_jumps[ player_skate.possible_jump_count ++ ] = 
+            *jump;
 
-      v3_lerp( start, end, t, pos );
-      return 1;
-   }
-   else
-   {
-      v3_copy( end, pos );
-      return 0;
+         continue;
+invalidated_grind:;
+      }
    }
-}
 
 
-/* 
- * Handles connection between the player and the ground
- *
- * TODO: Must save original velocity to use here
- */
-VG_STATIC void skate_apply_interface_model( player_instance *player,
-                                            rb_ct *manifold, int len )
-{
-   struct player_skate *s = &player->_skate;
+   float score_min =  INFINITY,
+         score_max = -INFINITY;
 
-   if( !((s->state.activity == k_skate_activity_ground) ||
-         (s->state.activity == k_skate_activity_air )) )
-      return;
+   jump_info *best = NULL;
 
-   if( s->state.activity == k_skate_activity_air )
-      s->debug_normal_pressure = 0.0f;
-   else
-      s->debug_normal_pressure = v3_dot( player->rb.to_world[1], player->rb.v );
+   for( int i=0; i<player_skate.possible_jump_count; i ++ ){
+      jump_info *jump = &player_skate.possible_jumps[i];
 
-   /* springs */
-   v3f spring0, spring1;
+      if( jump->score < score_min )
+         best = jump;
 
-   skate_get_board_points( player, spring1, spring0 );
-   int spring_hit0 = 0, //skate_simulate_spring( player, s, spring0 ),
-       spring_hit1 = 0; //skate_simulate_spring( player, s, spring1 );
+      score_min = vg_minf( score_min, jump->score );
+      score_max = vg_maxf( score_max, jump->score );
+   }
 
-   v3f animavg, animdelta;
-   v3_add( spring0, spring1, animavg );
-   v3_muls( animavg, 0.5f, animavg );
+   for( int i=0; i<player_skate.possible_jump_count; i ++ ){
+      jump_info *jump = &player_skate.possible_jumps[i];
+      float s = jump->score;
 
-   v3_sub( spring1, spring0, animdelta );
-   v3_normalize( animdelta );
+      s -= score_min;
+      s /= (score_max-score_min);
+      s  = 1.0f - s;
 
-   m4x3_mulv( player->rb.to_local, animavg, s->board_offset );
+      jump->score = s;
+      jump->colour = s * 255.0f;
 
-   float dx = -v3_dot( animdelta, player->rb.to_world[2] ),
-         dy =  v3_dot( animdelta, player->rb.to_world[1] );
+      if( jump == best )
+         jump->colour <<= 16;
+      else if( jump->type == k_prediction_land )
+         jump->colour <<= 8;
+      
+      jump->colour |= 0xff000000;
+   }
 
-   float angle = -atan2f( dy, dx );
-   q_axis_angle( s->board_rotation, (v3f){1.0f,0.0f,0.0f}, angle );
+   if( best ){
+      v3_copy( best->n, state->land_normal );
+      v3_copy( best->v, localplayer.rb.v );
+      state->land_dist = best->land_dist;
+      state->gravity_bias = best->gravity;
 
-   int lift_frames_limit = 6;
+      if( best->type == k_prediction_grind ){
+         state->activity = k_skate_activity_air_to_grind;
+      }
 
-   /* Surface connection */
-   if( len == 0 && !(spring_hit0 && spring_hit1) )
-   {
-      s->state.lift_frames ++;
+      v2f steer;
+      joystick_state( k_srjoystick_steer, steer );
+      v2_normalize_clamp( steer );
 
-      if( s->state.lift_frames >= lift_frames_limit )
-         s->state.activity = k_skate_activity_air;
+      if( (fabsf(steer[1]) > 0.5f) && (state->land_dist >= 1.5f) ){
+         state->flip_rate = (1.0f/state->land_dist) * vg_signf(steer[1]) *
+                                 state->reverse ;
+         state->flip_time = 0.0f;
+         v3_copy( localplayer.rb.to_world[0], state->flip_axis );
+      }
+      else{
+         state->flip_rate = 0.0f;
+         v3_zero( state->flip_axis );
+      }
    }
    else
-   {
-      v3f surface_avg;
-      v3_zero( surface_avg );
-
-      for( int i=0; i<len; i++ )
-         v3_add( surface_avg, manifold[i].n, surface_avg );
-      v3_normalize( surface_avg );
-      
-      if( v3_dot( player->rb.v, surface_avg ) > 0.7f )
-      {
-         s->state.lift_frames ++;
+      v3_copy( (v3f){0,1,0}, state->land_normal );
+}
 
-         if( s->state.lift_frames >= lift_frames_limit )
-            s->state.activity = k_skate_activity_air;
-      }
-      else
-      {
-         s->state.activity = k_skate_activity_ground;
-         s->state.lift_frames = 0;
-         v3f projected, axis;
-
-         if( s->state.activity_prev == k_skate_activity_air )
-         {
-            player->cam_land_punch_v += v3_dot( player->rb.v, surface_avg ) *
-                                          k_cam_punch;
-         }
+/*
+ *
+ * Varius physics models
+ * ------------------------------------------------
+ */
 
-         float const DOWNFORCE = -k_downforce*VG_TIMESTEP_FIXED;
-         v3_muladds( player->rb.v, player->rb.to_world[1], 
-                     DOWNFORCE, player->rb.v );
+/*
+ * Air control, no real physics
+ */
+static void skate_apply_air_model(void){
+   struct player_skate_state *state = &player_skate.state;
 
-         float d = v3_dot( player->rb.to_world[2], surface_avg );
-         v3_muladds( surface_avg, player->rb.to_world[2], -d, projected );
-         v3_normalize( projected );
+   if( state->activity_prev > k_skate_activity_air_to_grind )
+      player__approximate_best_trajectory();
 
-         float angle = v3_dot( player->rb.to_world[1], projected );
-         v3_cross( player->rb.to_world[1], projected, axis );
+   float angle = v3_dot( localplayer.rb.to_world[1], state->land_normal );
+   angle = vg_clampf( angle, -1.0f, 1.0f );
+   v3f axis; 
+   v3_cross( localplayer.rb.to_world[1], state->land_normal, axis );
 
-#if 0
-         if( fabsf(angle) < 0.9999f )
-         {
-            v4f correction;
-            q_axis_angle( correction, axis, 
-                          acosf(angle)*4.0f*VG_TIMESTEP_FIXED );
-            q_mul( correction, player->rb.q, player->rb.q );
-         }
-#endif
-      }
-   }
+   v4f correction;
+   q_axis_angle( correction, axis, 
+                  acosf(angle)*2.0f*VG_TIMESTEP_FIXED );
+   q_mul( correction, localplayer.rb.q, localplayer.rb.q );
 }
 
-VG_STATIC int player_skate_trick_input( player_instance *player );
-VG_STATIC void skate_apply_trick_model( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+static enum trick_type player_skate_trick_input(void);
+static void skate_apply_trick_model(void){
+   struct player_skate_state *state = &player_skate.state;
 
    v3f Fd, Fs, F;
    v3f strength = { 3.7f, 3.6f, 8.0f };
 
-   v3_muls( s->board_trick_residualv, -4.0f , Fd );
-   v3_muls( s->board_trick_residuald, -10.0f, Fs );
+   v3_muls( state->trick_residualv, -4.0f , Fd );
+   v3_muls( state->trick_residuald, -10.0f, Fs );
    v3_add( Fd, Fs, F );
    v3_mul( strength, F, F );
 
-   v3_muladds( s->board_trick_residualv, F, k_rb_delta, 
-               s->board_trick_residualv );
-   v3_muladds( s->board_trick_residuald, s->board_trick_residualv,
-               k_rb_delta, s->board_trick_residuald );
+   v3_muladds( state->trick_residualv, F, k_rb_delta, 
+               state->trick_residualv );
+   v3_muladds( state->trick_residuald, state->trick_residualv,
+               k_rb_delta, state->trick_residuald );
 
-   if( s->state.activity == k_skate_activity_air )
-   {
-      if( v3_length2( s->state.trick_vel ) < 0.0001f )
+   if( state->activity <= k_skate_activity_air_to_grind ){
+      if( v3_length2( state->trick_vel ) < 0.0001f )
          return;
 
-      int carry_on = player_skate_trick_input( player );
+      int carry_on = state->trick_type == player_skate_trick_input();
 
       /* we assume velocities share a common divisor, in which case the 
        * interval is the minimum value (if not zero) */
 
       float min_rate = 99999.0f;
 
-      for( int i=0; i<3; i++ )
-      {
-         float v = s->state.trick_vel[i];
+      for( int i=0; i<3; i++ ){
+         float v = state->trick_vel[i];
          if( (v > 0.0f) && (v < min_rate) )
             min_rate = v;
       }
 
       float interval = 1.0f / min_rate,
-            current  = floorf( s->state.trick_time / interval ),
-            next_end = (current+1.0f) * interval;
+            current  = floorf( state->trick_time ),
+            next_end = current+1.0f;
 
 
       /* integrate trick velocities */
-      v3_muladds( s->state.trick_euler, s->state.trick_vel, k_rb_delta,
-                  s->state.trick_euler );
+      v3_muladds( state->trick_euler, state->trick_vel, k_rb_delta,
+                  state->trick_euler );
 
-      if( !carry_on && (s->state.trick_time + k_rb_delta >= next_end) )
-      {
-         s->state.trick_time = 0.0f;
-         s->state.trick_euler[0] = roundf( s->state.trick_euler[0] );
-         s->state.trick_euler[1] = roundf( s->state.trick_euler[1] );
-         s->state.trick_euler[2] = roundf( s->state.trick_euler[2] );
-         v3_copy( s->state.trick_vel, s->board_trick_residualv );
-         v3_zero( s->state.trick_vel );
-      }
+      if( !carry_on && (state->trick_time + k_rb_delta/interval >= next_end) ){
+         state->trick_time = 0.0f;
+         state->trick_euler[0] = roundf( state->trick_euler[0] );
+         state->trick_euler[1] = roundf( state->trick_euler[1] );
+         state->trick_euler[2] = roundf( state->trick_euler[2] );
+         v3_copy( state->trick_vel, state->trick_residualv );
+         v3_zero( state->trick_vel );
 
-      s->state.trick_time += k_rb_delta;
+         audio_lock();
+         audio_oneshot_3d( &audio_flips[vg_randu32(&vg.rand)%4], 
+               localplayer.rb.co, 40.0f, 1.0f );
+         audio_unlock();
+      }
+      else 
+         state->trick_time += k_rb_delta / interval;
    }
-   else
-   {
-      if( (s->state.lift_frames == 0) 
-          && (v3_length2(s->state.trick_vel) >= 0.0001f ) &&
-          s->state.trick_time > 0.2f)
+   else{
+      if( (v3_length2(state->trick_vel) >= 0.0001f ) &&
+          state->trick_time > 0.2f)
       {
-         player__dead_transition( player );
+         player__skate_kill_audio();
+         player__dead_transition();
       }
 
-      s->state.trick_euler[0] = roundf( s->state.trick_euler[0] );
-      s->state.trick_euler[1] = roundf( s->state.trick_euler[1] );
-      s->state.trick_euler[2] = roundf( s->state.trick_euler[2] );
-      s->state.trick_time = 0.0f;
-      v3_zero( s->state.trick_vel );
+      state->trick_euler[0] = roundf( state->trick_euler[0] );
+      state->trick_euler[1] = roundf( state->trick_euler[1] );
+      state->trick_euler[2] = roundf( state->trick_euler[2] );
+      state->trick_time = 0.0f;
+      v3_zero( state->trick_vel );
    }
 }
 
-VG_STATIC void skate_apply_grab_model( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+static void skate_apply_grab_model(void){
+   struct player_skate_state *state = &player_skate.state;
 
-   float grabt = player->input_grab->axis.value;
+   float grabt = axis_state( k_sraxis_grab );
 
-   if( grabt > 0.5f )
-   {
-      v2_muladds( s->state.grab_mouse_delta, vg.mouse_delta, 0.02f, 
-                  s->state.grab_mouse_delta );
+   if( grabt > 0.5f ){
+      v2_muladds( state->grab_mouse_delta, vg.mouse_delta, 0.02f, 
+                  state->grab_mouse_delta );
 
-      v2_normalize_clamp( s->state.grab_mouse_delta );
+      v2_normalize_clamp( state->grab_mouse_delta );
    }
    else
-      v2_zero( s->state.grab_mouse_delta );
+      v2_zero( state->grab_mouse_delta );
+
+   state->grabbing = vg_lerpf( state->grabbing, grabt, 8.4f*k_rb_delta );
+}
+
+static void skate_apply_steering_model(void){
+   struct player_skate_state *state = &player_skate.state;
+
+   v2f jsteer;
+   joystick_state( k_srjoystick_steer, jsteer );
+
+   /* Steering */
+   float steer = jsteer[0],
+         grab  = axis_state( k_sraxis_grab );
 
-   s->state.grabbing = vg_lerpf( s->state.grabbing, grabt, 8.4f*k_rb_delta );
+   steer = vg_signf( steer ) * steer*steer * k_steer_ground;
+
+   v3f steer_axis;
+   v3_muls( localplayer.rb.to_world[1], -vg_signf( steer ), steer_axis );
+
+   float rate = 26.0f,
+         top  = 1.0f;
+
+   if( state->activity <= k_skate_activity_air_to_grind ){
+      rate = 6.0f * fabsf(steer);
+      top  = 1.5f;
+   }
+   else{
+      /* rotate slower when grabbing on ground */
+      steer *= (1.0f-(state->jump_charge+grab)*0.4f);
+
+      if( state->activity == k_skate_activity_grind_5050 ){
+         rate = 0.0f;
+         top  = 0.0f;
+      }
+
+      else if( state->activity >= k_skate_activity_grind_any ){
+         rate *= fabsf(steer);
+
+         float a = 0.8f * -steer * k_rb_delta;
+
+         v4f q;
+         q_axis_angle( q, localplayer.rb.to_world[1], a );
+         q_mulv( q, player_skate.grind_vec, player_skate.grind_vec );
+
+         v3_normalize( player_skate.grind_vec );
+      }
+
+      else if( state->manual_direction ){
+         rate = 35.0f;
+         top  = 1.5f;
+      }
+      
+      if( grab < 0.5f ){
+         top *= 1.0f+v3_length( state->throw_v )*k_mmthrow_steer;
+      }
+   }
+
+   float current  = v3_dot( localplayer.rb.to_world[1], localplayer.rb.w ),
+         addspeed = (steer * -top) - current,
+         maxaccel = rate * k_rb_delta,
+         accel    = vg_clampf( addspeed, -maxaccel, maxaccel );
+
+   v3_muladds( localplayer.rb.w, localplayer.rb.to_world[1], 
+               accel, localplayer.rb.w );
 }
 
 /*
  * Computes friction and surface interface model
  */
-VG_STATIC void skate_apply_friction_model( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-
-   if( s->state.activity != k_skate_activity_ground )
-      return;
+static void skate_apply_friction_model(void){
+   struct player_skate_state *state = &player_skate.state;
 
    /*
     * Computing localized friction forces for controlling the character
@@ -826,7 +860,7 @@ VG_STATIC void skate_apply_friction_model( player_instance *player )
     */
 
    v3f vel;
-   m3x3_mulv( player->rb.to_local, player->rb.v, vel );
+   m3x3_mulv( localplayer.rb.to_local, localplayer.rb.v, vel );
    float slip = 0.0f;
    
    if( fabsf(vel[2]) > 0.01f )
@@ -835,24 +869,23 @@ VG_STATIC void skate_apply_friction_model( player_instance *player )
    if( fabsf( slip ) > 1.2f )
       slip = vg_signf( slip ) * 1.2f;
 
-   s->state.slip = slip;
-   s->state.reverse = -vg_signf(vel[2]);
+   state->slip = slip;
+   state->reverse = -vg_signf(vel[2]);
 
    vel[0] += vg_cfrictf( vel[0], k_friction_lat * k_rb_delta );
    vel[2] += vg_cfrictf( vel[2], k_friction_resistance * k_rb_delta );
 
    /* Pushing additive force */
 
-   if( !player->input_jump->button.value )
-   {
-      if( player->input_push->button.value )
+   if( !button_press( k_srbind_jump ) ){
+      if( button_press( k_srbind_push ) || (vg.time-state->start_push<0.75) )
       {
-         if( (vg.time - s->state.cur_push) > 0.25 )
-            s->state.start_push = vg.time;
+         if( (vg.time - state->cur_push) > 0.25 )
+            state->start_push = vg.time;
 
-         s->state.cur_push = vg.time;
+         state->cur_push = vg.time;
 
-         double push_time = vg.time - s->state.start_push;
+         double push_time = vg.time - state->start_push;
 
          float cycle_time = push_time*k_push_cycle_rate,
                accel      = k_push_accel * (sinf(cycle_time)*0.5f+0.5f),
@@ -861,151 +894,142 @@ VG_STATIC void skate_apply_friction_model( player_instance *player )
                new_vel    = vg_minf( current + amt, k_max_push_speed ),
                delta      = new_vel - vg_minf( current, k_max_push_speed );
 
-         vel[2] += delta * -s->state.reverse;
+         vel[2] += delta * -state->reverse;
       }
    }
 
    /* Send back to velocity */
-   m3x3_mulv( player->rb.to_world, vel, player->rb.v );
-   
-   /* Steering */
-   float input = player->input_js1h->axis.value,
-         grab  = player->input_grab->axis.value,
-         steer = input * (1.0f-(s->state.jump_charge+grab)*0.4f),
-         steer_scaled = vg_signf(steer) * powf(steer,2.0f) * k_steer_ground;
-
-   s->state.steery -= steer_scaled * k_rb_delta;
+   m3x3_mulv( localplayer.rb.to_world, vel, localplayer.rb.v );
 }
 
-VG_STATIC void skate_apply_jump_model( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-   int charging_jump_prev = s->state.charging_jump;
-   s->state.charging_jump = player->input_jump->button.value;
+static void skate_apply_jump_model(void){
+   struct player_skate_state *state = &player_skate.state;
+   int charging_jump_prev = state->charging_jump;
+   state->charging_jump = button_press( k_srbind_jump );
 
    /* Cannot charge this in air */
-   if( s->state.activity != k_skate_activity_ground )
-      s->state.charging_jump = 0;
+   if( state->activity <= k_skate_activity_air_to_grind ){
+      state->charging_jump = 0;
+      return;
+   }
 
-   if( s->state.charging_jump )
-   {
-      s->state.jump_charge += k_rb_delta * k_jump_charge_speed;
+   if( state->charging_jump ){
+      state->jump_charge += k_rb_delta * k_jump_charge_speed;
 
       if( !charging_jump_prev )
-         s->state.jump_dir = s->state.reverse>0.0f? 1: 0;
+         state->jump_dir = state->reverse>0.0f? 1: 0;
    }
-   else
-   {
-      s->state.jump_charge -= k_jump_charge_speed * VG_TIMESTEP_FIXED;
+   else{
+      state->jump_charge -= k_jump_charge_speed * k_rb_delta;
    }
 
-   s->state.jump_charge = vg_clampf( s->state.jump_charge, 0.0f, 1.0f );
-
-   if( s->state.activity == k_skate_activity_air )
-      return;
+   state->jump_charge = vg_clampf( state->jump_charge, 0.0f, 1.0f );
 
    /* player let go after charging past 0.2: trigger jump */
-   if( (!s->state.charging_jump) && (s->state.jump_charge > 0.2f) )
-   {
+   if( (!state->charging_jump) && (state->jump_charge > 0.2f) ){
       v3f jumpdir;
       
       /* Launch more up if alignment is up else improve velocity */
-      float aup = v3_dot( (v3f){0.0f,1.0f,0.0f}, player->rb.to_world[1] ),
+      float aup = localplayer.rb.to_world[1][1],
             mod = 0.5f,
             dir = mod + fabsf(aup)*(1.0f-mod);
 
-      v3_copy( player->rb.v, jumpdir );
-      v3_normalize( jumpdir );
-      v3_muls( jumpdir, 1.0f-dir, jumpdir );
-      v3_muladds( jumpdir, player->rb.to_world[1], dir, jumpdir );
-      v3_normalize( jumpdir );
+      if( state->activity == k_skate_activity_ground ){
+         v3_copy( localplayer.rb.v, jumpdir );
+         v3_normalize( jumpdir );
+         v3_muls( jumpdir, 1.0f-dir, jumpdir );
+         v3_muladds( jumpdir, localplayer.rb.to_world[1], dir, jumpdir );
+         v3_normalize( jumpdir );
+      }else{
+         v3_copy( state->up_dir, jumpdir );
+         state->grind_cooldown = 30;
+         state->activity = k_skate_activity_ground;
+
+         v2f steer;
+         joystick_state( k_srjoystick_steer, steer );
+
+         float tilt  = steer[0] * 0.3f;
+               tilt *= vg_signf(v3_dot( localplayer.rb.v, 
+                                        player_skate.grind_dir ));
+
+         v4f qtilt;
+         q_axis_angle( qtilt, player_skate.grind_dir, tilt );
+         q_mulv( qtilt, jumpdir, jumpdir );
+      }
+      state->surface_cooldown = 10;
       
-      float force = k_jump_force*s->state.jump_charge;
-      v3_muladds( player->rb.v, jumpdir, force, player->rb.v );
-      s->state.jump_charge = 0.0f;
-      s->state.jump_time = vg.time;
-
-      v2f steer = { player->input_js1h->axis.value,
-                    player->input_js1v->axis.value };
-      v2_normalize_clamp( steer );
-
-      float maxspin = k_steer_air * k_rb_delta * k_spin_boost;
-      s->state.steery_s = -steer[0] * maxspin;
-      s->state.steerx = s->state.steerx_s;
-      s->state.lift_frames ++;
-
-      /* FIXME audio events */
-#if 0
-      audio_lock();
-      audio_player_set_flags( &audio_player_extra, AUDIO_FLAG_SPACIAL_3D );
-      audio_player_set_position( &audio_player_extra, player.rb.co );
-      audio_player_set_vol( &audio_player_extra, 20.0f );
-      audio_player_playclip( &audio_player_extra, &audio_jumps[rand()%2] );
-      audio_unlock();
-#endif
+      float force = k_jump_force*state->jump_charge;
+      v3_muladds( localplayer.rb.v, jumpdir, force, localplayer.rb.v );
+      state->jump_charge = 0.0f;
+      state->jump_time = vg.time;
+      player__networked_sfx( k_player_subsystem_skate, 32, 
+                             k_player_skate_soundeffect_jump,
+                             localplayer.rb.co, 1.0f );
    }
 }
 
-VG_STATIC void skate_apply_pump_model( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+static void skate_apply_pump_model(void){
+   struct player_skate_state *state = &player_skate.state;
+
+   if( state->activity != k_skate_activity_ground ){
+      v3_zero( state->throw_v );
+      return;
+   }
 
    /* Throw / collect routine 
-    *
-    * TODO: Max speed boost
     */
-   if( player->input_grab->axis.value > 0.5f )
-   {
-      if( s->state.activity == k_skate_activity_ground )
-      {
+   if( axis_state( k_sraxis_grab ) > 0.5f ){
+      if( state->activity == k_skate_activity_ground ){
          /* Throw */
-         v3_muls( player->rb.to_world[1], k_mmthrow_scale, s->state.throw_v );
+         v3_muls( localplayer.rb.to_world[1], k_mmthrow_scale, state->throw_v );
       }
    }
-   else
-   {
+   else{
       /* Collect */
-      float doty = v3_dot( player->rb.to_world[1], s->state.throw_v );
+      float doty = v3_dot( localplayer.rb.to_world[1], state->throw_v );
       
       v3f Fl, Fv;
-      v3_muladds( s->state.throw_v, player->rb.to_world[1], -doty, Fl);
+      v3_muladds( state->throw_v, localplayer.rb.to_world[1], -doty, Fl);
 
-      if( s->state.activity == k_skate_activity_ground )
-      {
-         v3_muladds( player->rb.v,     Fl,  k_mmcollect_lat, player->rb.v );
-         v3_muladds( s->state.throw_v, Fl, -k_mmcollect_lat, s->state.throw_v );
+      if( state->activity == k_skate_activity_ground ){
+         if( v3_length2(localplayer.rb.v)<(20.0f*20.0f) ){
+            v3_muladds( localplayer.rb.v, Fl, 
+                        k_mmcollect_lat, localplayer.rb.v );
+         }
+         v3_muladds( state->throw_v, Fl, -k_mmcollect_lat, state->throw_v );
       }
 
-      v3_muls( player->rb.to_world[1], -doty, Fv );
-      v3_muladds( player->rb.v,     Fv, k_mmcollect_vert, player->rb.v );
-      v3_muladds( s->state.throw_v, Fv, k_mmcollect_vert, s->state.throw_v );
+      v3_muls( localplayer.rb.to_world[1], -doty, Fv );
+      v3_muladds( localplayer.rb.v,     Fv, k_mmcollect_vert, localplayer.rb.v );
+      v3_muladds( state->throw_v, Fv, k_mmcollect_vert, state->throw_v );
    }
 
    /* Decay */
-   if( v3_length2( s->state.throw_v ) > 0.0001f )
-   {
+   if( v3_length2( state->throw_v ) > 0.0001f ){
       v3f dir;
-      v3_copy( s->state.throw_v, dir );
+      v3_copy( state->throw_v, dir );
       v3_normalize( dir );
 
-      float max = v3_dot( dir, s->state.throw_v ),
+      float max = v3_dot( dir, state->throw_v ),
             amt = vg_minf( k_mmdecay * k_rb_delta, max );
-      v3_muladds( s->state.throw_v, dir, -amt, s->state.throw_v );
+      v3_muladds( state->throw_v, dir, -amt, state->throw_v );
    }
 }
 
-VG_STATIC void skate_apply_cog_model( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+static void skate_apply_cog_model(void){
+   struct player_skate_state *state = &player_skate.state;
+
+   v3f ideal_cog, ideal_diff, ideal_dir;
+   v3_copy( state->up_dir, ideal_dir );
+   v3_normalize( ideal_dir );
 
-   v3f ideal_cog, ideal_diff;
-   v3_muladds( player->rb.co, player->rb.to_world[1],
-               1.0f-player->input_grab->axis.value, ideal_cog );
-   v3_sub( ideal_cog, s->state.cog, ideal_diff );
+   float grab = axis_state( k_sraxis_grab );
+   v3_muladds( localplayer.rb.co, ideal_dir, 1.0f-grab, ideal_cog );
+   v3_sub( ideal_cog, state->cog, ideal_diff );
 
    /* Apply velocities */
    v3f rv;
-   v3_sub( player->rb.v, s->state.cog_v, rv );
+   v3_sub( localplayer.rb.v, state->cog_v, rv );
 
    v3f F;
    v3_muls( ideal_diff, -k_cog_spring * k_rb_rate, F );
@@ -1015,784 +1039,2301 @@ VG_STATIC void skate_apply_cog_model( player_instance *player )
          rb = 1.0f-k_cog_mass_ratio;
 
    /* Apply forces & intergrate */
-   v3_muladds( s->state.cog_v, F, -rb, s->state.cog_v );
-   s->state.cog_v[1] += -9.8f * k_rb_delta;
-   v3_muladds( s->state.cog, s->state.cog_v, k_rb_delta, s->state.cog );
+   v3_muladds( state->cog_v, F, -rb, state->cog_v );
+   state->cog_v[1] += -9.8f * k_rb_delta;
+   v3_muladds( state->cog, state->cog_v, k_rb_delta, state->cog );
 }
 
-VG_STATIC void skate_collision_response( player_instance *player,
-                                         rb_ct *manifold, int len )
-{
-   struct player_skate *s = &player->_skate;
+static void skate_integrate(void){
+   struct player_skate_state *state = &player_skate.state;
 
-   for( int j=0; j<10; j++ )
-   {
-      for( int i=0; i<len; i++ )
-      {
-         struct contact *ct = &manifold[i];
-         
-         v3f dv, delta;
-         v3_sub( ct->co, player->rb.co, delta ); 
-         v3_cross( player->rb.w, delta, dv );
-         v3_add( player->rb.v, dv, dv );
+   float rate_x = 1.0f - (k_rb_delta * 3.0f),
+         rate_z = rate_x,
+         rate_y = 1.0f;
 
-         float vn = -v3_dot( dv, ct->n );
-         vn += ct->bias;
+   if( state->activity >= k_skate_activity_grind_any ){
+      rate_x = 1.0f-(16.0f*k_rb_delta);
+      rate_y = 1.0f-(10.0f*k_rb_delta);
+      rate_z = 1.0f-(40.0f*k_rb_delta);
+   }
 
-         float temp = ct->norm_impulse;
-         ct->norm_impulse = vg_maxf( temp + vn, 0.0f );
-         vn = ct->norm_impulse - temp;
+   float wx = v3_dot( localplayer.rb.w, localplayer.rb.to_world[0] ) * rate_x,
+         wy = v3_dot( localplayer.rb.w, localplayer.rb.to_world[1] ) * rate_y,
+         wz = v3_dot( localplayer.rb.w, localplayer.rb.to_world[2] ) * rate_z;
 
-         v3f impulse;
-         v3_muls( ct->n, vn, impulse );
+   v3_muls(                  localplayer.rb.to_world[0], wx, localplayer.rb.w );
+   v3_muladds( localplayer.rb.w, localplayer.rb.to_world[1], wy, 
+               localplayer.rb.w );
+   v3_muladds( localplayer.rb.w, localplayer.rb.to_world[2], wz, 
+               localplayer.rb.w );
 
-         if( fabsf(v3_dot( impulse, player->rb.to_world[2] )) > 10.0f ||
-             fabsf(v3_dot( impulse, player->rb.to_world[1] )) > 50.0f )
-         {
-            player__dead_transition( player );
-            return;
-         }
+   state->flip_time += state->flip_rate * k_rb_delta;
+   rb_update_transform( &localplayer.rb );
+}
 
-         v3_add( impulse, player->rb.v, player->rb.v );
-         v3_cross( delta, impulse, impulse );
+static enum trick_type player_skate_trick_input(void){
+   return (button_press( k_srbind_trick0 )     ) |
+          (button_press( k_srbind_trick1 ) << 1) |
+          (button_press( k_srbind_trick2 ) << 1) |
+          (button_press( k_srbind_trick2 )     );
+}
 
-         /*
-          * W Impulses are limited to the Y and X axises, we don't really want
-          * roll angular velocities being included.
-          *
-          * Can also tweak the resistance of each axis here by scaling the wx,wy
-          * components.
-          */
-         
-         float wy = v3_dot( player->rb.to_world[1], impulse ) * 0.8f,
-               wx = v3_dot( player->rb.to_world[0], impulse ) * 1.0f,
-               wz = v3_dot( player->rb.to_world[2], impulse ) * 2.0f;
+static void player__skate_pre_update(void){
+   struct player_skate_state *state = &player_skate.state;
+
+   if( button_down( k_srbind_use ) ){
+      localplayer.subsystem = k_player_subsystem_walk;
+
+      v3f angles;
+      v3_copy( localplayer.cam.angles, localplayer.angles );
+      localplayer.angles[2] = 0.0f;
+
+      v3f newpos, offset;
+      m4x3_mulv( localplayer.rb.to_world, (v3f){0.0f,1.0f,0.0f}, newpos );
+      v3_add( newpos, (v3f){0.0f,-1.0f,0.0f}, newpos );
+      v3_sub( localplayer.rb.co, newpos, offset );
+      v3_copy( newpos, localplayer.rb.co );
+
+      player__begin_holdout( offset );
+      player__skate_kill_audio();
+      player__walk_transition();
+      return;
+   }
+
+   if( state->activity <= k_skate_activity_air_to_grind ){
+      enum trick_type trick = k_trick_type_none;
+      if( (trick = player_skate_trick_input()) ){
+         if( state->trick_time == 0.0f ){
+            audio_lock();
+            audio_oneshot_3d( &audio_flips[vg_randu32(&vg.rand)%4], 
+                  localplayer.rb.co, 40.0f, 1.0f );
+            audio_unlock();
+         }
 
-         v3_muladds( player->rb.w, player->rb.to_world[1], wy, player->rb.w );
-         v3_muladds( player->rb.w, player->rb.to_world[0], wx, player->rb.w );
-         v3_muladds( player->rb.w, player->rb.to_world[2], wz, player->rb.w );
+         if( state->trick_time < 0.1f ){
+            v3_zero( state->trick_vel );
+
+            if( trick == k_trick_type_kickflip ){
+               state->trick_vel[0] = 3.0f;
+            }
+            else if( trick == k_trick_type_shuvit ){
+               state->trick_vel[2] = 3.0f;
+            }
+            else if( trick == k_trick_type_treflip ){
+               state->trick_vel[0] = 2.0f;
+               state->trick_vel[2] = 2.0f;
+            }
+            state->trick_type = trick;
+         }
       }
    }
+   else
+      state->trick_type = k_trick_type_none;
 }
 
-VG_STATIC void skate_integrate( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+static void player__skate_post_update(void){
+   struct player_skate_state *state = &player_skate.state;
 
-   /* integrate rigidbody velocities */
-#ifndef SKATE_CCD
-   v3f gravity = { 0.0f, -9.6f, 0.0f };
-   v3_muladds( player->rb.v, gravity, k_rb_delta, player->rb.v );
-   v3_muladds( player->rb.co, player->rb.v, k_rb_delta, player->rb.co );
-#endif
+   for( int i=0; i<player_skate.possible_jump_count; i++ ){
+      jump_info *jump = &player_skate.possible_jumps[i];
 
-   float decay_rate = 0.5f*0.125f;
+      if( jump->log_length == 0 ){
+         vg_fatal_error( "assert: jump->log_length == 0\n" );
+      }
+      
+      for( int j=0; j<jump->log_length - 1; j ++ ){
+         float brightness = jump->score*jump->score*jump->score;
+         v3f p1;
+         v3_lerp( jump->log[j], jump->log[j+1], brightness, p1 );
+         vg_line( jump->log[j], p1, jump->colour );
+      }
 
-   if( s->state.activity == k_skate_activity_air )
-   {
-      float dist = 1.0f-(s->land_dist/4.0f);
-      decay_rate = 0.5f * vg_maxf( dist*dist, 0.0f );
-   }
+      vg_line_cross( jump->log[jump->log_length-1], jump->colour, 0.25f );
 
-   v3_lerp( player->rb.w, (v3f){0.0f,0.0f,0.0f}, decay_rate, player->rb.w );
+      v3f p1;
+      v3_add( jump->log[jump->log_length-1], jump->n, p1 );
+      vg_line( jump->log[jump->log_length-1], p1, 0xffffffff );
 
-#ifndef SKATE_CCD
-   if( v3_length2( player->rb.w ) > 0.0f )
-   {
-      v4f rotation;
-      v3f axis;
-      v3_copy( player->rb.w, axis );
-      
-      float mag = v3_length( axis );
-      v3_divs( axis, mag, axis );
-      q_axis_angle( rotation, axis, mag*k_rb_delta );
-      q_mul( rotation, player->rb.q, player->rb.q );
+      vg_line_point( jump->apex, 0.02f, 0xffffffff );
    }
-#endif
 
-   /* integrate steering velocities */
-   v4f rotate; 
-   float l = (s->state.activity == k_skate_activity_air)? 0.04f: 0.24f;
+   audio_lock();
 
-   s->state.steery_s = vg_lerpf( s->state.steery_s, s->state.steery, l );
-   s->state.steerx_s = vg_lerpf( s->state.steerx_s, s->state.steerx, l );
+   float air   = state->activity <= k_skate_activity_air_to_grind? 1.0f: 0.0f,
+         speed = v3_length( localplayer.rb.v ),
+         attn  = vg_minf( 1.0f, speed*0.1f ),
+         slide = vg_clampf( fabsf(state->slip), 0.0f, 1.0f );
 
-   q_axis_angle( rotate, player->rb.to_world[1], s->state.steery_s );
-   q_mul( rotate, player->rb.q, player->rb.q );
+   if( state->activity >= k_skate_activity_grind_any ){
+      slide = 0.0f;
+   }
 
-   q_axis_angle( rotate, player->rb.to_world[0], s->state.steerx_s );
-   q_mul( rotate, player->rb.q, player->rb.q );
+   f32 gate        = skaterift.time_rate,
+       vol_main    = sqrtf( (1.0f-air)*attn*(1.0f-slide) * 0.4f ) * gate,
+       vol_air     = sqrtf(       air *attn * 0.5f )              * gate,
+       vol_slide   = sqrtf( (1.0f-air)*attn*slide * 0.25f )       * gate;
 
-   s->state.steerx = 0.0f;
-   s->state.steery = 0.0f;
+   const u32 flags = AUDIO_FLAG_SPACIAL_3D|AUDIO_FLAG_LOOP;
 
-   s->state.flip_time += s->state.flip_rate * k_rb_delta;
-   rb_update_transform( &player->rb );
-}
+   if( !player_skate.aud_air ){
+      player_skate.aud_air = audio_get_first_idle_channel();
+      if( player_skate.aud_air )
+         audio_channel_init( player_skate.aud_air, &audio_board[1], flags );
+   }
 
-/*
- * 1 2 or 3
- */
+   if( !player_skate.aud_slide ){
+      player_skate.aud_slide = audio_get_first_idle_channel();
+      if( player_skate.aud_slide ) 
+         audio_channel_init( player_skate.aud_slide, &audio_board[2], flags );
+   }
 
-VG_STATIC int player_skate_trick_input( player_instance *player )
-{
-   return (player->input_trick0->button.value) |
-          (player->input_trick1->button.value << 1) |
-          (player->input_trick2->button.value << 1) |
-          (player->input_trick2->button.value);
-}
 
-VG_STATIC void player__skate_pre_update( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+   /* brrrrrrrrrrrt sound for tiles and stuff 
+    * --------------------------------------------------------*/
+   float sidechain_amt = 0.0f,
+         hz            = vg_maxf( speed * 2.0f, 2.0f );
 
-   if( vg_input_button_down( player->input_use ) )
-   {
-      player->subsystem = k_player_subsystem_walk;
+   if( (player_skate.surface == k_surface_prop_tiles) &&
+       (state->activity < k_skate_activity_grind_any) )
+      sidechain_amt = 1.0f;
+   else
+      sidechain_amt = 0.0f;
 
-      v3f angles;
-      v3_copy( player->cam.angles, angles );
-      angles[2] = 0.0f;
+   audio_set_lfo_frequency( 0, hz );
+   audio_set_lfo_wave( 0, k_lfo_polynomial_bipolar, 
+                          vg_lerpf( 250.0f, 80.0f, attn ) );
 
-      player__walk_transition( player, angles );
-      return;
+   if( player_skate.sample_change_cooldown > 0.0f ){
+      player_skate.sample_change_cooldown -= vg.time_frame_delta;
    }
-
-   int trick_id; 
-   if( (s->state.lift_frames > 0) &&
-       (trick_id = player_skate_trick_input( player )) )
-   {
-      if( (vg.time - s->state.jump_time) < 0.1f )
+   else{
+      int sample_type = k_skate_sample_concrete;
+
+      if( state->activity == k_skate_activity_grind_5050 ){
+         if( player_skate.surface == k_surface_prop_metal )
+            sample_type = k_skate_sample_metal_scrape_generic;
+         else
+            sample_type = k_skate_sample_concrete_scrape_metal;
+      }
+      else if( (state->activity == k_skate_activity_grind_back50) ||
+               (state->activity == k_skate_activity_grind_front50) )
       {
-         v3_zero( s->state.trick_vel );
-         s->state.trick_time = 0.0f;
-
-         if( trick_id == 1 )
-         {
-            s->state.trick_vel[0] = 3.0f;
+         if( player_skate.surface == k_surface_prop_metal ){
+            sample_type = k_skate_sample_metal_scrape_generic;
          }
-         else if( trick_id == 2 )
-         {
-            s->state.trick_vel[2] = 3.0f;
-         }
-         else if( trick_id == 3 )
-         {
-            s->state.trick_vel[0] = 2.0f;
-            s->state.trick_vel[2] = 2.0f;
+         else{
+            float a = v3_dot( localplayer.rb.to_world[2], 
+                              player_skate.grind_dir );
+            if( fabsf(a) > 0.70710678118654752f )
+               sample_type = k_skate_sample_concrete_scrape_wood;
+            else 
+               sample_type = k_skate_sample_concrete_scrape_metal;
          }
       }
+      else if( state->activity == k_skate_activity_grind_boardslide ){
+         if( player_skate.surface == k_surface_prop_metal )
+            sample_type = k_skate_sample_metal_scrape_generic;
+         else
+            sample_type = k_skate_sample_concrete_scrape_wood;
+      }
+
+      audio_clip *relevant_samples[] = {
+         &audio_board[0],
+         &audio_board[0],
+         &audio_board[7],
+         &audio_board[6],
+         &audio_board[5]
+      };
+
+      if( (player_skate.main_sample_type != sample_type) || 
+          (!player_skate.aud_main) ){
+
+         player_skate.aud_main = 
+            audio_channel_crossfade( player_skate.aud_main, 
+                                     relevant_samples[sample_type],
+                                     0.06f, flags );
+         player_skate.sample_change_cooldown = 0.1f;
+         player_skate.main_sample_type = sample_type;
+      }
    }
-}
 
-VG_STATIC void player__skate_post_update( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-   for( int i=0; i<s->prediction_count; i++ )
-   {
-      struct land_prediction *p = &s->predictions[i];
-      
-      for( int j=0; j<p->log_length - 1; j ++ )
-         vg_line( p->log[j], p->log[j+1], p->colour );
+   if( player_skate.aud_main ){
+      player_skate.aud_main->colour = 0x00103efe;
+      audio_channel_set_spacial( player_skate.aud_main, 
+                                 localplayer.rb.co, 40.0f );
+      //audio_channel_slope_volume( player_skate.aud_main, 0.05f, vol_main );
+      audio_channel_edit_volume( player_skate.aud_main, vol_main, 1 );
+      audio_channel_sidechain_lfo( player_skate.aud_main, 0, sidechain_amt );
 
-      vg_line_cross( p->log[p->log_length-1], p->colour, 0.25f );
+      float rate = 1.0f + (attn-0.5f)*0.2f;
+      audio_channel_set_sampling_rate( player_skate.aud_main, rate );
+   }
 
-      v3f p1;
-      v3_add( p->log[p->log_length-1], p->n, p1 );
-      vg_line( p->log[p->log_length-1], p1, 0xffffffff );
+   if( player_skate.aud_slide ){
+      player_skate.aud_slide->colour = 0x00103efe;
+      audio_channel_set_spacial( player_skate.aud_slide, 
+                                 localplayer.rb.co, 40.0f );
+      //audio_channel_slope_volume( player_skate.aud_slide, 0.05f, vol_slide );
+      audio_channel_edit_volume( player_skate.aud_slide, vol_slide, 1 );
+      audio_channel_sidechain_lfo( player_skate.aud_slide, 0, sidechain_amt );
+   }
 
-      vg_line_pt3( p->apex, 0.02f, 0xffffffff );
+   if( player_skate.aud_air ){
+      player_skate.aud_air->colour = 0x00103efe;
+      audio_channel_set_spacial( player_skate.aud_air, 
+                                 localplayer.rb.co, 40.0f );
+      //audio_channel_slope_volume( player_skate.aud_air, 0.05f, vol_air );
+      audio_channel_edit_volume( player_skate.aud_air, vol_air, 1 );
    }
 
-   vg_line_pt3( s->state.apex, 0.200f, 0xff0000ff );
-   vg_line_pt3( s->state.apex, 0.201f, 0xff00ffff );
+   audio_unlock();
 }
 
-VG_STATIC void player__skate_update( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-   v3_copy( player->rb.co, s->state.prev_pos );
-   s->state.activity_prev = s->state.activity;
+/*
+ * truck alignment model at ra(local)
+ * returns 1 if valid surface:
+ *             surface_normal will be filled out with an averaged normal vector
+ *             axel_dir will be the direction from left to right wheels
+ *
+ * returns 0 if no good surface found
+ */
+static 
+int skate_compute_surface_alignment( v3f ra, u32 colour,
+                                     v3f surface_normal, v3f axel_dir ){
+   world_instance *world = world_current_instance();
 
-   float l = k_board_length,
-         w = 0.13f;
+   v3f truck, left, right;
+   m4x3_mulv( localplayer.rb.to_world, ra, truck );
 
-   v3f wheel_positions[] = 
-   {
-      { -w, 0.0f, -l },
-      {  w, 0.0f, -l },
-      { -w, 0.0f,  l },
-      {  w, 0.0f,  l },
-   };
+   v3_muladds( truck, localplayer.rb.to_world[0], -k_board_width, left  );
+   v3_muladds( truck, localplayer.rb.to_world[0],  k_board_width, right );
+   vg_line( left, right, colour );
 
-   rb_sphere collider;
-   collider.radius = 0.07f;
+   float k_max_truck_flex = VG_PIf * 0.25f;
+   
+   ray_hit ray_l, ray_r;
 
-   s->substep = k_rb_delta;
+   v3f dir;
+   v3_muls( localplayer.rb.to_world[1], -1.0f, dir );
 
-begin_collision:;
+   int res_l = 0, res_r = 0;
 
-#ifdef SKATE_CCD
+   for( int i=0; i<8; i++ ){
+      float t = 1.0f - (float)i * (1.0f/8.0f);
+      v3_muladds( truck, localplayer.rb.to_world[0], -k_board_radius*t, left );
+      v3_muladds( left,  localplayer.rb.to_world[1],  k_board_radius,   left );
+      ray_l.dist = 2.1f * k_board_radius;
 
-   /* calculate transform one step into future */
-   v3f future_co;
-   v4f future_q;
-   v3_muladds( player->rb.co, player->rb.v, s->substep, future_co );
+      res_l = ray_world( world, left, dir, &ray_l, k_material_flag_walking );
 
-   if( v3_length2( player->rb.w ) > 0.0f )
-   {
-      v4f rotation;
-      v3f axis;
-      v3_copy( player->rb.w, axis );
-      
-      float mag = v3_length( axis );
-      v3_divs( axis, mag, axis );
-      q_axis_angle( rotation, axis, mag*s->substep );
-      q_mul( rotation, player->rb.q, future_q );
-      q_normalize( future_q );
+      if( res_l )
+         break;
    }
 
-   /* calculate the minimum time we can move */
-   float max_time = s->substep,
-         cast_radius = collider.radius - 0.05f;
+   for( int i=0; i<8; i++ ){
+      float t = 1.0f - (float)i * (1.0f/8.0f);
+      v3_muladds( truck, localplayer.rb.to_world[0],  k_board_radius*t, right );
+      v3_muladds( right, localplayer.rb.to_world[1],  k_board_radius,   right );
+      ray_r.dist = 2.1f * k_board_radius;
 
-   for( int i=0; i<4; i++ )
-   {
-      v3f current, future;
-      q_mulv( future_q, wheel_positions[i], future );
-      v3_add( future, future_co, future );
+      res_r = ray_world( world, right, dir, &ray_r, k_material_flag_walking );
 
-      q_mulv( player->rb.q, wheel_positions[i], current );
-      v3_add( current, player->rb.co, current );
-      
-      float t;    /* TODO: ignore lightly grazing normals? */
-      v3f n;
-      if( spherecast_world( current, future, cast_radius, &t, n ) != -1)
-      {
-         max_time = vg_minf( max_time, t * s->substep );
-      }
+      if( res_r )
+         break;
    }
 
-   /* clamp to a fraction of delta, to prevent locking */
-   max_time = vg_minf( vg_maxf( max_time, k_rb_delta*0.025f ), s->substep );
-   s->substep_delta = max_time;
+   v3f v0;
+   v3f midpoint;
+   v3f tangent_average;
+   v3_muladds( truck, localplayer.rb.to_world[1], -k_board_radius, midpoint );
+   v3_zero( tangent_average );
+
+   if( res_l || res_r ){
+      v3f p0, p1, t;
+      v3_copy( midpoint, p0 );
+      v3_copy( midpoint, p1 );
+
+      if( res_l ){
+         v3_copy( ray_l.pos, p0 );
+         v3_cross( ray_l.normal, localplayer.rb.to_world[0], t );
+         v3_add( t, tangent_average, tangent_average );
+      }
+      if( res_r ){
+         v3_copy( ray_r.pos, p1 );
+         v3_cross( ray_r.normal, localplayer.rb.to_world[0], t );
+         v3_add( t, tangent_average, tangent_average );
+      }
 
-   /* integrate */
-   v3_muladds( player->rb.co, player->rb.v, s->substep_delta, player->rb.co );
-   if( v3_length2( player->rb.w ) > 0.0f )
-   {
-      v4f rotation;
-      v3f axis;
-      v3_copy( player->rb.w, axis );
-      
-      float mag = v3_length( axis );
-      v3_divs( axis, mag, axis );
-      q_axis_angle( rotation, axis, mag*s->substep_delta );
-      q_mul( rotation, player->rb.q, player->rb.q );
+      v3_sub( p1, p0, v0 );
+      v3_normalize( v0 );
+   }
+   else{
+      /* fallback: use the closes point to the trucks */
+      v3f closest;
+      int idx = bh_closest_point( world->geo_bh, midpoint, closest, 0.1f );
+
+      if( idx != -1 ){
+         u32 *tri = &world->scene_geo.arrindices[ idx * 3 ];
+         v3f verts[3];
+
+         for( int j=0; j<3; j++ )
+            v3_copy( world->scene_geo.arrvertices[ tri[j] ].co, verts[j] );
+
+         v3f vert0, vert1, n;
+         v3_sub( verts[1], verts[0], vert0 );
+         v3_sub( verts[2], verts[0], vert1 );
+         v3_cross( vert0, vert1, n );
+         v3_normalize( n );
+
+         if( v3_dot( n, localplayer.rb.to_world[1] ) < 0.3f )
+            return 0;
+
+         v3_cross( n, localplayer.rb.to_world[2], v0 );
+         v3_muladds( v0, localplayer.rb.to_world[2],
+                     -v3_dot( localplayer.rb.to_world[2], v0 ), v0 );
+         v3_normalize( v0 );
+
+         v3f t;
+         v3_cross( n, localplayer.rb.to_world[0], t );
+         v3_add( t, tangent_average, tangent_average );
+      }
+      else
+         return 0;
    }
 
-   rb_update_transform( &player->rb );
-
-   v3f gravity = { 0.0f, -9.6f, 0.0f };
-   v3_muladds( player->rb.v, gravity, s->substep_delta, player->rb.v );
+   v3_muladds( truck, v0,  k_board_width, right );
+   v3_muladds( truck, v0, -k_board_width, left );
 
-#else
-   
-   s->substep_delta = k_rb_delta;
+   vg_line( left, right, VG__WHITE );
 
-#endif
+   v3_normalize( tangent_average );
+   v3_cross( v0, tangent_average, surface_normal );
+   v3_copy( v0, axel_dir );
 
-   s->substep -= s->substep_delta;
+   return 1;
+}
 
+static void skate_weight_distribute(void){
+   struct player_skate_state *state = &player_skate.state;
+   v3_zero( player_skate.weight_distribution );
 
-   /* create manifold(s) */
-   rb_ct manifold[128];
+   int reverse_dir = v3_dot( localplayer.rb.to_world[2], 
+                             localplayer.rb.v ) < 0.0f?1:-1;
 
-   int manifold_len   = 0,
-       manifold_front = 0,
-       manifold_back  = 0,
-       manifold_interface = 0;
+   v2f steer;
+   joystick_state( k_srjoystick_steer, steer );
 
-   rb_ct *cmanifold = manifold;
+   if( state->manual_direction == 0 ){
+      if( (steer[1] > 0.7f) && (state->activity == k_skate_activity_ground) &&
+          (state->jump_charge <= 0.01f) )
+         state->manual_direction = reverse_dir;
+   }
+   else{
+      if( steer[1] < 0.1f ){
+         state->manual_direction = 0;
+      }
+      else{
+         if( reverse_dir != state->manual_direction ){
+            return;
+         }
+      }
+   }
 
-   for( int i=0; i<4; i++ )
-   {
-      m4x3f mtx;
-      m3x3_identity( mtx );
+   if( state->manual_direction ){
+      float amt = vg_minf( steer[1] * 8.0f, 1.0f );
+      player_skate.weight_distribution[2] = k_board_length * amt * 
+                                          (float)state->manual_direction;
+   }
 
-      m4x3_mulv( player->rb.to_world, wheel_positions[i], mtx[3] );
-      
-      int l = skate_collide_smooth( player, mtx, &collider, cmanifold );
+   if( state->manual_direction ){
+      v3f plane_z;
 
-      cmanifold += l;
-      manifold_len += l;
-      manifold_interface += l;
+      m3x3_mulv( localplayer.rb.to_world, player_skate.weight_distribution, 
+                 plane_z );
+      v3_negate( plane_z, plane_z );
 
-      if( i<=1 )
-         manifold_front ++;
-      else
-         manifold_back ++;
-   }
+      v3_muladds( plane_z, player_skate.surface_picture,
+                  -v3_dot( plane_z, player_skate.surface_picture ), plane_z );
+      v3_normalize( plane_z );
 
-   /* try to slap both wheels onto the ground when landing to prevent mega 
-    * angular velocities being added */
-   if( (s->state.activity == k_skate_activity_air) && 
-       (manifold_front != manifold_back ) )
-   {
-      v3f trace_from, trace_dir;
-      v3_muls( player->rb.to_world[1], -1.0f, trace_dir );
+      v3_muladds( plane_z, player_skate.surface_picture, 0.3f, plane_z );
+      v3_normalize( plane_z );
 
-      if( manifold_front )
-         v3_copy( (v3f){0.0f,0.0f, k_board_length}, trace_from );
-      else
-         v3_copy( (v3f){0.0f,0.0f,-k_board_length}, trace_from );
-      m4x3_mulv( player->rb.to_world, trace_from, trace_from );
+      v3f p1;
+      v3_muladds( localplayer.rb.co, plane_z, 1.5f, p1 );
+      vg_line( localplayer.rb.co, p1, VG__GREEN );
 
-      ray_hit ray;
-      ray.dist = 0.6f;
+      v3f refdir;
+      v3_muls( localplayer.rb.to_world[2], -(float)state->manual_direction,
+               refdir );
 
-      if( ray_world( trace_from, trace_dir, &ray ) )
-      {
-         rb_ct *ct = cmanifold;
+      rb_effect_spring_target_vector( &localplayer.rb, refdir, plane_z,
+                                       k_manul_spring, k_manul_dampener,
+                                       player_skate.substep_delta );
+   }
+}
 
-         v3_copy( ray.pos, ct->co );
-         v3_copy( ray.normal, ct->n );
-         ct->p = 0.0f;
+static void skate_adjust_up_direction(void){
+   struct player_skate_state *state = &player_skate.state;
 
-         manifold_len ++;
-         manifold_interface ++;
-      }
-   }
+   if( state->activity == k_skate_activity_ground ){
+      v3f target;
+      v3_copy( player_skate.surface_picture, target );
 
-   int grind_len = skate_grind_collide( player, cmanifold );
-   manifold_len += grind_len;
+      target[1] += 2.0f * player_skate.surface_picture[1];
+      v3_normalize( target );
 
-   for( int i=0; i<manifold_len; i ++ )
-   {
-#ifdef SKATE_CCD
-      rb_ct *ct = &manifold[i];
-      ct->bias = -0.2f * 
-                  (s->substep_delta * 3600.0f)
-                  * vg_minf( 0.0f, -ct->p+k_penetration_slop );
-      rb_tangent_basis( ct->n, ct->t[0], ct->t[1] );
-      ct->norm_impulse = 0.0f;
-      ct->tangent_impulse[0] = 0.0f;
-      ct->tangent_impulse[1] = 0.0f;
-#else
-      rb_prepare_contact( &manifold[i] );
-#endif
-      rb_debug_contact( &manifold[i] );
+      v3_lerp( state->up_dir, target,
+               8.0f * player_skate.substep_delta, state->up_dir );
    }
+   else if( state->activity <= k_skate_activity_air_to_grind ){
+      v3_lerp( state->up_dir, localplayer.rb.to_world[1],
+               8.0f * player_skate.substep_delta, state->up_dir );
+   }
+   else{
+      v3f avg;
+      v3_add( localplayer.rb.to_world[1], (v3f){0,1,0}, avg );
+      v3_normalize( avg );
 
-   skate_collision_response( player, manifold, manifold_len );
-
-   if( s->substep >= 0.0001f )
-      goto begin_collision;
+      v3_lerp( state->up_dir, avg,
+               6.0f * player_skate.substep_delta, state->up_dir );
+   }
+}
 
-   skate_apply_grind_model( player, &manifold[manifold_interface], grind_len );
-   skate_apply_interface_model( player, manifold, manifold_interface );
+static int skate_point_visible( v3f origin, v3f target ){
+   v3f dir;
+   v3_sub( target, origin, dir );
    
-   skate_apply_pump_model( player );
-   skate_apply_cog_model( player );
-
-   skate_apply_grab_model( player );
-   skate_apply_friction_model( player );
-   skate_apply_jump_model( player );
-   skate_apply_air_model( player );
-   skate_apply_trick_model( player );
+   ray_hit ray;
+   ray.dist = v3_length( dir );
+   v3_muls( dir, 1.0f/ray.dist, dir );
+   ray.dist -= 0.025f;
 
-   skate_integrate( player );
+   if( ray_world( world_current_instance(), origin, dir, &ray, 
+                  k_material_flag_walking ) )
+      return 0;
 
-   vg_line_pt3( s->state.cog, 0.1f,  VG__WHITE );
-   vg_line_pt3( s->state.cog, 0.11f, VG__WHITE );
-   vg_line_pt3( s->state.cog, 0.12f, VG__WHITE );
-   vg_line_pt3( s->state.cog, 0.13f, VG__WHITE );
-   vg_line_pt3( s->state.cog, 0.14f, VG__WHITE );
+   return 1;
+}
 
-   vg_line( player->rb.co, s->state.cog, VG__RED );
+static void skate_grind_orient( struct grind_info *inf, m3x3f mtx ){
+   v3_copy( inf->dir, mtx[0] );
+   v3_copy( inf->n, mtx[1] );
+   v3_cross( mtx[0], mtx[1], mtx[2] );
+}
 
-   teleport_gate *gate;
-   if( (gate = world_intersect_gates( player->rb.co, s->state.prev_pos )) )
-   {
-      m4x3_mulv( gate->transport, player->rb.co, player->rb.co );
-      m3x3_mulv( gate->transport, player->rb.v,  player->rb.v );
-      m4x3_mulv( gate->transport, s->state.cog,   s->state.cog );
-      m3x3_mulv( gate->transport, s->state.cog_v, s->state.cog_v );
-      m3x3_mulv( gate->transport, s->state.throw_v, s->state.throw_v );
+static void skate_grind_friction( struct grind_info *inf, float strength ){
+   v3f v2;
+   v3_muladds( localplayer.rb.to_world[2], inf->n, 
+               -v3_dot( localplayer.rb.to_world[2], inf->n ), v2 );
 
-      v4f transport_rotation;
-      m3x3_q( gate->transport, transport_rotation );
-      q_mul( transport_rotation, player->rb.q, player->rb.q );
-      rb_update_transform( &player->rb );
+   float a        = 1.0f-fabsf( v3_dot( v2, inf->dir ) ),
+         dir      = vg_signf( v3_dot( localplayer.rb.v, inf->dir ) ),
+         F        = a * -dir * k_grind_max_friction;
 
-      s->state_gate_storage = s->state;
-      player__pass_gate( player, gate );
-   }
+   v3_muladds( localplayer.rb.v, inf->dir, F*k_rb_delta*strength, 
+               localplayer.rb.v );
 }
 
-VG_STATIC void player__skate_im_gui( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-
-   /* FIXME: Compression */
-   player__debugtext( 1, "V:  %5.2f %5.2f %5.2f",player->rb.v[0],
-                                                player->rb.v[1],
-                                                player->rb.v[2] );
-   player__debugtext( 1, "CO: %5.2f %5.2f %5.2f",player->rb.co[0],
-                                                player->rb.co[1],
-                                                player->rb.co[2] );
-   player__debugtext( 1, "W:  %5.2f %5.2f %5.2f",player->rb.w[0],
-                                                player->rb.w[1],
-                                                player->rb.w[2] );
-
-   player__debugtext( 1, "activity: %s",
-                           (const char *[]){ "k_skate_activity_air",
-                                             "k_skate_activity_ground",
-                                             "k_skate_activity_grind }" }
-                                             [s->state.activity] );
-   player__debugtext( 1, "steer_s: %5.2f %5.2f [%.2f %.2f]",
-                        s->state.steerx_s, s->state.steery_s,
-                        k_steer_ground, k_steer_air );
-   player__debugtext( 1, "flip: %.4f %.4f", s->state.flip_rate, 
-                                             s->state.flip_time );
-   player__debugtext( 1, "trickv: %.2f %.2f %.2f", 
-                           s->state.trick_vel[0],
-                           s->state.trick_vel[1],
-                           s->state.trick_vel[2] );
-   player__debugtext( 1, "tricke: %.2f %.2f %.2f", 
-                           s->state.trick_euler[0],
-                           s->state.trick_euler[1],
-                           s->state.trick_euler[2] );
-}
+static void skate_grind_decay( struct grind_info *inf, float strength ){
+   m3x3f mtx, mtx_inv;
+   skate_grind_orient( inf, mtx );
+   m3x3_transpose( mtx, mtx_inv );
 
-VG_STATIC void player__skate_animate( player_instance *player,
-                                     player_animation *dest )
-{
-   struct player_skate *s = &player->_skate;
-   struct player_avatar *av = player->playeravatar;
-   struct skeleton *sk = &av->sk;
+   v3f v_grind;
+   m3x3_mulv( mtx_inv, localplayer.rb.v, v_grind );
 
-   /* Head */
-   float kheight = 2.0f,
-         kleg = 0.6f;
+   float decay = 1.0f - ( k_rb_delta * k_grind_decayxy * strength );
+   v3_mul( v_grind, (v3f){ 1.0f, decay, decay }, v_grind );
+   m3x3_mulv( mtx, v_grind, localplayer.rb.v );
+}
 
-   v3f offset;
-   v3_zero( offset );
+static void skate_grind_truck_apply( float sign, struct grind_info *inf,
+                                        float strength ){
+   struct player_skate_state *state = &player_skate.state;
+   /* REFACTOR */
+   v3f ra = { 0.0f, -k_board_radius, sign * k_board_length };
+   v3f raw, wsp;
+   m3x3_mulv( localplayer.rb.to_world, ra, raw );
+   v3_add( localplayer.rb.co, raw, wsp );
 
-   m4x3_mulv( player->rb.to_local, s->state.cog, offset );
-   v3_muls( offset, -4.0f, offset );
+   v3_copy( ra, player_skate.weight_distribution );
 
-   float curspeed  = v3_length( player->rb.v ),
-         kickspeed = vg_clampf( curspeed*(1.0f/40.0f), 0.0f, 1.0f ),
-         kicks     = (vg_randf()-0.5f)*2.0f*kickspeed,
-         sign      = vg_signf( kicks );
+   v3f delta;
+   v3_sub( inf->co, wsp, delta );
 
-   s->wobble[0] = vg_lerpf( s->wobble[0], kicks*kicks*sign, 6.0f*vg.time_delta);
-   s->wobble[1] = vg_lerpf( s->wobble[1], s->wobble[0],     2.4f*vg.time_delta);
+   /* spring force */
+   v3_muladds( localplayer.rb.v, delta, k_spring_force*strength*k_rb_delta, 
+               localplayer.rb.v );
 
-   offset[0] *= 0.26f;
-   offset[0] += s->wobble[1]*3.0f;
+   skate_grind_decay( inf, strength );
+   skate_grind_friction( inf, strength );
 
-   offset[1] *= -0.3f;
-   offset[2] *= 0.01f;
+   /* yeah yeah yeah yeah */
+   v3f raw_nplane, axis;
+   v3_muladds( raw, inf->n, -v3_dot( inf->n, raw ), raw_nplane );
+   v3_cross( raw_nplane, inf->n, axis );
+   v3_normalize( axis );
 
-   offset[0]=vg_clampf(offset[0],-0.8f,0.8f)*(1.0f-fabsf(s->blend_slide)*0.9f);
-   offset[1]=vg_clampf(offset[1],-0.5f,0.0f);
+   /* orientation */
+   m3x3f mtx;
+   skate_grind_orient( inf, mtx );
+   v3f target_fwd, fwd, up, target_up;
+   m3x3_mulv( mtx, player_skate.grind_vec, target_fwd );
+   v3_copy( raw_nplane, fwd );
+   v3_copy( localplayer.rb.to_world[1], up );
+   v3_copy( inf->n, target_up );
 
-   /* 
-    * Animation blending
-    * ===========================================
-    */
-   
-   /* sliding */
-   {
-      float desired  = vg_clampf( fabsf( s->state.slip ), 0.0f, 1.0f );
-      s->blend_slide = vg_lerpf( s->blend_slide, desired, 2.4f*vg.time_delta);
-   }
-   
-   /* movement information */
-   {
-      int iair = (s->state.activity == k_skate_activity_air) ||
-                 (s->state.activity == k_skate_activity_grind );
+   v3_muladds( target_fwd, inf->n, -v3_dot(inf->n,target_fwd), target_fwd );
+   v3_muladds( fwd, inf->n, -v3_dot(inf->n,fwd), fwd );
 
-      float dirz = s->state.reverse > 0.0f? 0.0f: 1.0f,
-            dirx = s->state.slip < 0.0f?    0.0f: 1.0f,
-            fly  = iair?                    1.0f: 0.0f;
+   v3_normalize( target_fwd );
+   v3_normalize( fwd );
 
-      s->blend_z    = vg_lerpf( s->blend_z,   dirz, 2.4f*vg.time_delta );
-      s->blend_x    = vg_lerpf( s->blend_x,   dirx, 0.6f*vg.time_delta );
-      s->blend_fly  = vg_lerpf( s->blend_fly, fly,  2.4f*vg.time_delta );
-   }
+   v2f steer;
+   joystick_state( k_srjoystick_steer, steer );
 
-   mdl_keyframe apose[32], bpose[32];
-   mdl_keyframe ground_pose[32];
-   {
-      /* when the player is moving fast he will crouch down a little bit */
-      float stand = 1.0f - vg_clampf( curspeed * 0.03f, 0.0f, 1.0f );
-      s->blend_stand = vg_lerpf( s->blend_stand, stand, 6.0f*vg.time_delta );
+   float way = steer[1] * vg_signf( v3_dot( raw_nplane, localplayer.rb.v ) );
 
-      /* stand/crouch */
-      float dir_frame   = s->blend_z * (15.0f/30.0f),
-            stand_blend = offset[1]*-2.0f;
+   v4f q;
+   q_axis_angle( q, axis, VG_PIf*0.125f * way );
+   q_mulv( q, target_up,  target_up );
+   q_mulv( q, target_fwd, target_fwd );
 
-      v3f local_cog;
-      m4x3_mulv( player->rb.to_local, s->state.cog, local_cog );
+   rb_effect_spring_target_vector( &localplayer.rb, up, target_up,
+                                    k_grind_spring, 
+                                    k_grind_dampener,
+                                    k_rb_delta );
 
-      stand_blend = vg_clampf( 1.0f-local_cog[1], 0, 1 );
+   rb_effect_spring_target_vector( &localplayer.rb, fwd, target_fwd,
+                                    k_grind_spring*strength, 
+                                    k_grind_dampener*strength,
+                                    k_rb_delta );
 
-      skeleton_sample_anim( sk, s->anim_stand, dir_frame, apose );
-      skeleton_sample_anim( sk, s->anim_highg, dir_frame, bpose );
-      skeleton_lerp_pose( sk, apose, bpose, stand_blend, apose );
+   vg_line_arrow( localplayer.rb.co, target_up, 1.0f, VG__GREEN );
+   vg_line_arrow( localplayer.rb.co, fwd, 0.8f, VG__RED );
+   vg_line_arrow( localplayer.rb.co, target_fwd, 1.0f, VG__YELOW );
 
-      /* sliding */
-      float slide_frame = s->blend_x * (15.0f/30.0f);
-      skeleton_sample_anim( sk, s->anim_slide, slide_frame, bpose );
-      skeleton_lerp_pose( sk, apose, bpose, s->blend_slide, apose );
-
-      /* pushing */
-      double push_time = vg.time - s->state.start_push;
-      s->blend_push = vg_lerpf( s->blend_push,
-                               (vg.time - s->state.cur_push) < 0.125,
-                               6.0f*vg.time_delta );
-
-      float pt = push_time + vg.accumulator;
-      if( s->state.reverse > 0.0f )
-         skeleton_sample_anim( sk, s->anim_push, pt, bpose );
-      else
-         skeleton_sample_anim( sk, s->anim_push_reverse, pt, bpose );
+   player_skate.grind_strength = strength;
 
-      skeleton_lerp_pose( sk, apose, bpose, s->blend_push, apose );
+   /* Fake contact */
+   struct grind_limit *limit = 
+      &player_skate.limits[ player_skate.limit_count ++ ];
+   m4x3_mulv( localplayer.rb.to_local, wsp, limit->ra );
+   m3x3_mulv( localplayer.rb.to_local, inf->n, limit->n );
+   limit->p = 0.0f;
 
-      /* trick setup */
-      float jump_start_frame = 14.0f/30.0f;
+   v3_copy( inf->dir, player_skate.grind_dir );
+}
 
-      float charge = s->state.jump_charge;
-      s->blend_jump = vg_lerpf( s->blend_jump, charge, 8.4f*vg.time_delta );
+static void skate_5050_apply( struct grind_info *inf_front,
+                                 struct grind_info *inf_back ){
+   struct player_skate_state *state = &player_skate.state;
+   struct grind_info inf_avg;
 
-      float setup_frame = charge * jump_start_frame,
-            setup_blend = vg_minf( s->blend_jump, 1.0f );
-      
-      float jump_frame = (vg.time - s->state.jump_time) + jump_start_frame;
-      if( jump_frame >= jump_start_frame && jump_frame <= (40.0f/30.0f) )
-         setup_frame = jump_frame;
+   v3_sub( inf_front->co, inf_back->co, inf_avg.dir );
+   v3_muladds( inf_back->co, inf_avg.dir, 0.5f, inf_avg.co );
+   v3_normalize( inf_avg.dir );
 
-      struct skeleton_anim *jump_anim = s->state.jump_dir?
-                                        s->anim_ollie:
-                                        s->anim_ollie_reverse;
+   /* dont ask */
+   v3_muls( inf_avg.dir, vg_signf(v3_dot(inf_avg.dir,localplayer.rb.v)), 
+            inf_avg.dir );
 
-      skeleton_sample_anim_clamped( sk, jump_anim, setup_frame, bpose );
-      skeleton_lerp_pose( sk, apose, bpose, setup_blend, ground_pose );
-   }
-   
-   mdl_keyframe air_pose[32];
-   {
-      float target = -player->input_js1h->axis.value;
-      s->blend_airdir = vg_lerpf( s->blend_airdir, target, 2.4f*vg.time_delta );
-      
-      float air_frame = (s->blend_airdir*0.5f+0.5f) * (15.0f/30.0f);
-      skeleton_sample_anim( sk, s->anim_air, air_frame, apose );
+   v3f axis_front, axis_back, axis;
+   v3_cross( inf_front->dir, inf_front->n, axis_front );
+   v3_cross( inf_back->dir,  inf_back->n,  axis_back  );
+   v3_add( axis_front, axis_back, axis );
+   v3_normalize( axis );
 
-      static v2f grab_choice;
+   v3_cross( axis, inf_avg.dir, inf_avg.n );
+   skate_grind_decay( &inf_avg, 1.0f );
+
+   v2f steer;
+   joystick_state( k_srjoystick_steer, steer );
+
+   float way = steer[1] * vg_signf( v3_dot( localplayer.rb.to_world[2], 
+                                            localplayer.rb.v ) );
+   v4f q;
+   v3f up, target_up;
+   v3_copy( localplayer.rb.to_world[1], up );
+   v3_copy( inf_avg.n, target_up );
+   q_axis_angle( q, localplayer.rb.to_world[0], VG_PIf*0.25f * -way );
+   q_mulv( q, target_up,  target_up );
+
+   v3_zero( player_skate.weight_distribution );
+   player_skate.weight_distribution[2] = k_board_length * -way;
+
+   rb_effect_spring_target_vector( &localplayer.rb, up, target_up,
+                                    k_grind_spring, 
+                                    k_grind_dampener,
+                                    k_rb_delta );
+   vg_line_arrow( localplayer.rb.co, up, 1.0f, VG__GREEN );
+   vg_line_arrow( localplayer.rb.co, target_up, 1.0f, VG__GREEN );
+
+   v3f fwd_nplane, dir_nplane;
+   v3_muladds( localplayer.rb.to_world[2], inf_avg.n,
+               -v3_dot( localplayer.rb.to_world[2], inf_avg.n ), fwd_nplane );
+
+   v3f dir;
+   v3_muls( inf_avg.dir, v3_dot( fwd_nplane, inf_avg.dir ), dir );
+   v3_muladds( dir, inf_avg.n, -v3_dot( dir, inf_avg.n ), dir_nplane );
+
+   v3_normalize( fwd_nplane );
+   v3_normalize( dir_nplane );
+
+   rb_effect_spring_target_vector( &localplayer.rb, fwd_nplane, dir_nplane,
+                                    1000.0f,
+                                    k_grind_dampener,
+                                    k_rb_delta );
+   vg_line_arrow( localplayer.rb.co, fwd_nplane, 0.8f, VG__RED );
+   vg_line_arrow( localplayer.rb.co, dir_nplane, 0.8f, VG__RED );
+
+   v3f pos_front = { 0.0f, -k_board_radius, -1.0f * k_board_length },
+       pos_back  = { 0.0f, -k_board_radius,  1.0f * k_board_length },
+       delta_front, delta_back, delta_total;
+
+   m4x3_mulv( localplayer.rb.to_world, pos_front, pos_front );
+   m4x3_mulv( localplayer.rb.to_world, pos_back,  pos_back  );
+
+   v3_sub( inf_front->co, pos_front, delta_front );
+   v3_sub( inf_back->co,  pos_back, delta_back );
+   v3_add( delta_front, delta_back, delta_total );
+
+   v3_muladds( localplayer.rb.v, delta_total, 50.0f * k_rb_delta, 
+               localplayer.rb.v );
+
+   /* Fake contact */
+   struct grind_limit *limit = 
+      &player_skate.limits[ player_skate.limit_count ++ ];
+   v3_zero( limit->ra );
+   m3x3_mulv( localplayer.rb.to_local, inf_avg.n, limit->n );
+   limit->p = 0.0f;
+
+   v3_copy( inf_avg.dir, player_skate.grind_dir );
+}
 
-      v2f grab_input = { player->input_js2h->axis.value,
-                         player->input_js2v->axis.value };
-      v2_add( s->state.grab_mouse_delta, grab_input, grab_input );
-      if( v2_length2( grab_input ) <= 0.001f )
-         grab_input[0] = -1.0f;
-      else
-         v2_normalize_clamp( grab_input );
-      v2_lerp( grab_choice, grab_input, 2.4f*vg.time_delta, grab_choice );
+static int skate_grind_truck_renew( f32 sign, struct grind_info *inf ){
+   struct player_skate_state *state = &player_skate.state;
 
-      float ang = atan2f( grab_choice[0], grab_choice[1] ),
-            ang_unit = (ang+VG_PIf) * (1.0f/VG_TAUf),
-            grab_frame = ang_unit * (15.0f/30.0f);
+   v3f wheel_co = { 0.0f, 0.0f,            sign * k_board_length },
+       grind_co = { 0.0f, -k_board_radius, sign * k_board_length };
 
-      skeleton_sample_anim( sk, s->anim_grabs, grab_frame, bpose );
-      skeleton_lerp_pose( sk, apose, bpose, s->state.grabbing, air_pose );
-   }
+   m4x3_mulv( localplayer.rb.to_world, wheel_co, wheel_co );
+   m4x3_mulv( localplayer.rb.to_world, grind_co, grind_co );
 
-   skeleton_lerp_pose( sk, ground_pose, air_pose, s->blend_fly, dest->pose );
+   /* Exit condition: lost grind tracking */
+   if( !skate_grind_scansq( grind_co, localplayer.rb.v, 0.3f, inf ) )
+      return 0;
 
-   float add_grab_mod = 1.0f - s->blend_fly;
+   /* Exit condition: cant see grind target directly */
+   if( !skate_point_visible( wheel_co, inf->co ) )
+      return 0;
 
-   /* additive effects */
-   {
-      u32 apply_to[] = { av->id_hip, 
-                         av->id_ik_hand_l,
-                         av->id_ik_hand_r,
-                         av->id_ik_elbow_l,
-                         av->id_ik_elbow_r };
+   /* Exit condition: minimum velocity not reached, but allow a bit of error */
+   float dv   = fabsf(v3_dot( localplayer.rb.v, inf->dir )),
+         minv = k_grind_axel_min_vel*0.8f;
 
-      for( int i=0; i<vg_list_size(apply_to); i ++ )
-      {
-         dest->pose[apply_to[i]-1].co[0] += offset[0]*add_grab_mod;
-         dest->pose[apply_to[i]-1].co[2] += offset[2]*add_grab_mod;
-      }
+   if( dv < minv )
+      return 0;
 
-      mdl_keyframe *kf_board  = &dest->pose[av->id_board-1],
-                   *kf_foot_l = &dest->pose[av->id_ik_foot_l-1],
-                   *kf_foot_r = &dest->pose[av->id_ik_foot_r-1];
+   if( fabsf(v3_dot( inf->dir, player_skate.grind_dir )) < k_grind_max_edge_angle )
+      return 0;
 
-      v3f bo;
-      v3_muls( s->board_offset, add_grab_mod, bo );
+   v3_copy( inf->dir, player_skate.grind_dir );
+   return 1;
+}
 
-      v3_add( bo, kf_board->co,  kf_board->co );
-      v3_add( bo, kf_foot_l->co, kf_foot_l->co );
-      v3_add( bo, kf_foot_r->co, kf_foot_r->co );
+static int skate_grind_truck_entry( f32 sign, struct grind_info *inf ){
+   struct player_skate_state *state = &player_skate.state;
 
-#if 0
-      m3x3f c;
-      q_m3x3( s->board_rotation, c );
-#endif
+   /* REFACTOR */
+   v3f ra = { 0.0f, -k_board_radius, sign * k_board_length };
 
-      v4f qtotal;
+   v3f raw, wsp;
+   m3x3_mulv( localplayer.rb.to_world, ra, raw );
+   v3_add( localplayer.rb.co, raw, wsp );
 
-      v4f qtrickr, qyawr, qpitchr, qrollr;
-      v3f eulerr;
+   if( skate_grind_scansq( wsp, localplayer.rb.v, 0.3, inf ) ){
+      if( fabsf(v3_dot( localplayer.rb.v, inf->dir )) < k_grind_axel_min_vel )
+         return 0;
 
+      /* velocity should be at least 60% aligned */
+      v3f pv, axis;
+      v3_cross( inf->n, inf->dir, axis );
+      v3_muladds( localplayer.rb.v, inf->n, 
+                  -v3_dot( localplayer.rb.v, inf->n ), pv );
       
+      if( v3_length2( pv ) < 0.0001f )
+         return 0;
+      v3_normalize( pv );
 
-      v3_muls( s->board_trick_residuald, VG_TAUf, eulerr );
-
-      q_axis_angle( qyawr,   (v3f){0.0f,1.0f,0.0f}, eulerr[0] * 0.5f );
-      q_axis_angle( qpitchr, (v3f){1.0f,0.0f,0.0f}, eulerr[1] );
-      q_axis_angle( qrollr,  (v3f){0.0f,0.0f,1.0f}, eulerr[2] );
+      if( fabsf(v3_dot( pv, inf->dir )) < k_grind_axel_max_angle )
+         return 0;
 
-      q_mul( qpitchr, qrollr, qtrickr );
-      q_mul( qyawr, qtrickr, qtrickr );
-      q_mul( s->board_rotation, qtrickr, qtotal );
-      q_normalize( qtotal );
+      if( v3_dot( localplayer.rb.v, inf->n ) > 0.5f )
+         return 0;
+      
+      v3f local_co, local_dir, local_n;
+      m4x3_mulv( localplayer.rb.to_local, inf->co,  local_co );
+      m3x3_mulv( localplayer.rb.to_local, inf->dir, local_dir );
+      m3x3_mulv( localplayer.rb.to_local, inf->n,   local_n );
 
-      q_mul( qtotal, kf_board->q, kf_board->q );
+      v2f delta = { local_co[0], local_co[2] - k_board_length*sign };
 
+      float truck_height = -(k_board_radius+0.03f);
 
-      v3f d;
-      v3_sub( kf_foot_l->co, bo, d );
-      q_mulv( qtotal, d, d );
-      v3_add( bo, d, kf_foot_l->co );
-      
-      v3_sub( kf_foot_r->co, bo, d );
-      q_mulv( qtotal, d, d );
-      v3_add( bo, d, kf_foot_r->co );
+      v3f rv;
+      v3_cross( localplayer.rb.w, raw, rv );
+      v3_add( localplayer.rb.v, rv, rv );
 
-      q_mul( s->board_rotation, kf_board->q, kf_board->q );
-      q_normalize( kf_board->q );
+      if( (local_co[1] >= truck_height) &&
+          (v2_length2( delta ) <= k_board_radius*k_board_radius) )
+      {
+         return 1;
+      }
+   }
 
+   return 0;
+}
 
-      /* trick rotation */
-      v4f qtrick, qyaw, qpitch, qroll;
-      v3f euler;
-      v3_muls( s->state.trick_euler, VG_TAUf, euler );
+static void skate_boardslide_apply( struct grind_info *inf ){
+   struct player_skate_state *state = &player_skate.state;
 
-      q_axis_angle( qyaw,   (v3f){0.0f,1.0f,0.0f}, euler[0] * 0.5f );
-      q_axis_angle( qpitch, (v3f){1.0f,0.0f,0.0f}, euler[1] );
-      q_axis_angle( qroll,  (v3f){0.0f,0.0f,1.0f}, euler[2] );
+   v3f local_co, local_dir, local_n;
+   m4x3_mulv( localplayer.rb.to_local, inf->co, local_co );
+   m3x3_mulv( localplayer.rb.to_local, inf->dir, local_dir );
+   m3x3_mulv( localplayer.rb.to_local, inf->n, local_n );
 
-      q_mul( qpitch, qroll, qtrick );
-      q_mul( qyaw, qtrick, qtrick );
-      q_mul( kf_board->q, qtrick, kf_board->q );
-      q_normalize( kf_board->q );
-   }
+   v3f intersection;
+   v3_muladds( local_co, local_dir, local_co[0]/-local_dir[0], 
+               intersection );
+   v3_copy( intersection, player_skate.weight_distribution );
 
-   /* transform */
-   rb_extrapolate( &player->rb, dest->root_co, dest->root_q );
-   v3_muladds( dest->root_co, player->rb.to_world[1], -0.28f, dest->root_co );
-
-   v4f qresy, qresx, qresidual;
-   m3x3f mtx_residual;
-   float substep = vg_clampf( vg.accumulator / VG_TIMESTEP_FIXED, 0.0f, 1.0f );
-   q_axis_angle( qresy, player->rb.to_world[1], s->state.steery_s*substep );
-   q_axis_angle( qresx, player->rb.to_world[0], s->state.steerx_s*substep );
-
-   q_mul( qresy, qresx, qresidual );
-   q_normalize( qresidual );
-   q_mul( dest->root_q, qresidual, dest->root_q );
-   q_normalize( dest->root_q );
-
-   v4f qflip;
-   if( (s->state.activity == k_skate_activity_air) &&
-       (fabsf(s->state.flip_rate) > 0.01f) )
-   {
-      float t = s->state.flip_time + s->state.flip_rate*substep*k_rb_delta,
-            angle = vg_clampf( t, -1.0f, 1.0f ) * VG_TAUf,
-            distm = s->land_dist * fabsf(s->state.flip_rate) * 3.0f,
-            blend = vg_clampf( 1.0f-distm, 0.0f, 1.0f );
+   skate_grind_decay( inf, 0.0125f );
+   skate_grind_friction( inf, 0.25f );
 
-      angle = vg_lerpf( angle, vg_signf(s->state.flip_rate) * VG_TAUf, blend );
+   /* direction alignment */
+   v3f dir, perp;
+   v3_cross( local_dir, local_n, perp );
+   v3_muls( local_dir, vg_signf(local_dir[0]), dir );
+   v3_muls( perp, vg_signf(perp[2]), perp );
 
-      q_axis_angle( qflip, s->state.flip_axis, angle );
-      q_mul( qflip, dest->root_q, dest->root_q );
-      q_normalize( dest->root_q );
+   m3x3_mulv( localplayer.rb.to_world, dir, dir );
+   m3x3_mulv( localplayer.rb.to_world, perp, perp );
 
-      v3f rotation_point, rco;
-      v3_muladds( player->rb.co, player->rb.to_world[1], 0.5f, rotation_point );
-      v3_sub( dest->root_co, rotation_point, rco );
-      
-      q_mulv( qflip, rco, rco );
-      v3_add( rco, rotation_point, dest->root_co );
-   }
-}
+   v4f qbalance;
+   q_axis_angle( qbalance, dir, local_co[0]*k_grind_balance );
+   q_mulv( qbalance, perp, perp );
 
-VG_STATIC void player__skate_post_animate( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-   struct player_avatar *av = player->playeravatar;
+   rb_effect_spring_target_vector( &localplayer.rb, localplayer.rb.to_world[0],
+                                    dir, 
+                                    k_grind_spring, k_grind_dampener,
+                                    k_rb_delta );
 
-   player->cam_velocity_influence = 1.0f;
-}
+   rb_effect_spring_target_vector( &localplayer.rb, localplayer.rb.to_world[2],
+                                    perp,
+                                    k_grind_spring, k_grind_dampener,
+                                    k_rb_delta );
 
-VG_STATIC void player__skate_reset_animator( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
+   vg_line_arrow( localplayer.rb.co, dir, 0.5f, VG__GREEN );
+   vg_line_arrow( localplayer.rb.co, perp, 0.5f, VG__BLUE );
 
-   if( s->state.activity == k_skate_activity_air )
-      s->blend_fly = 1.0f;
-   else
-      s->blend_fly = 0.0f;
-
-   s->blend_slide = 0.0f;
-   s->blend_z = 0.0f;
-   s->blend_x = 0.0f;
-   s->blend_stand = 0.0f;
-   s->blend_push = 0.0f;
-   s->blend_jump = 0.0f;
-   s->blend_airdir = 0.0f;
+   v3_copy( inf->dir, player_skate.grind_dir );
 }
 
-VG_STATIC void player__skate_clear_mechanics( player_instance *player )
-{
-   struct player_skate *s = &player->_skate;
-   s->state.jump_charge    = 0.0f;
-   s->state.lift_frames    = 0;
-   s->state.flip_rate      = 0.0f;
-   s->state.steery         = 0.0f;
-   s->state.steerx         = 0.0f;
-   s->state.steery_s       = 0.0f;
-   s->state.steerx_s       = 0.0f;
-   s->state.reverse        = 0.0f;
-   s->state.slip           = 0.0f;
-   v3_copy( player->rb.co, s->state.prev_pos );
-
-   m3x3_identity( s->state.velocity_bias );
-   m3x3_identity( s->state.velocity_bias_pstep );
-   v3_zero( s->state.throw_v );
-   v3_zero( s->state.trick_vel );
-   v3_zero( s->state.trick_euler );
-}
+static int skate_boardslide_entry( struct grind_info *inf ){
+   struct player_skate_state *state = &player_skate.state;
 
-VG_STATIC void player__skate_reset( player_instance *player,
-                                    struct respawn_point *rp )
-{
-   struct player_skate *s = &player->_skate;
-   v3_muladds( player->rb.co, player->rb.to_world[1], 1.0f, s->state.cog );
-   v3_zero( player->rb.v );
-   v3_zero( s->state.cog_v );
-   v4_copy( rp->q, player->rb.q );
+   if( skate_grind_scansq( localplayer.rb.co, 
+                           localplayer.rb.to_world[0], k_board_length,
+                           inf ) )
+   {
+      v3f local_co, local_dir;
+      m4x3_mulv( localplayer.rb.to_local, inf->co, local_co );
+      m3x3_mulv( localplayer.rb.to_local, inf->dir, local_dir );
+
+      if( (fabsf(local_co[2]) <= k_board_length) &&   /* within wood area */
+          (local_co[1] >= 0.0f) &&                    /* at deck level */
+          (fabsf(local_dir[0]) >= 0.25f) )            /* perpendicular to us */
+      {
+         if( fabsf(v3_dot( localplayer.rb.v, inf->dir )) < k_grind_axel_min_vel )
+            return 0;
+
+         return 1;
+      }
+   }
+
+   return 0;
+}
+
+static int skate_boardslide_renew( struct grind_info *inf ){
+   struct player_skate_state *state = &player_skate.state;
+
+   if( !skate_grind_scansq( localplayer.rb.co, 
+                            localplayer.rb.to_world[0], k_board_length,
+                            inf ) )
+      return 0;
+
+   /* Exit condition: cant see grind target directly */
+   v3f vis;
+   v3_muladds( localplayer.rb.co, localplayer.rb.to_world[1], 0.2f, vis );
+   if( !skate_point_visible( vis, inf->co ) )
+      return 0;
+
+   /* Exit condition: minimum velocity not reached, but allow a bit of error */
+   float dv   = fabsf(v3_dot( localplayer.rb.v, inf->dir )),
+         minv = k_grind_axel_min_vel*0.8f;
+
+   if( dv < minv )
+      return 0;
+
+   if( fabsf(v3_dot( inf->dir, player_skate.grind_dir )) < k_grind_max_edge_angle )
+      return 0;
+
+   return 1;
+}
+
+static void skate_store_grind_vec( struct grind_info *inf ){
+   struct player_skate_state *state = &player_skate.state;
+
+   m3x3f mtx;
+   skate_grind_orient( inf, mtx );
+   m3x3_transpose( mtx, mtx );
+
+   v3f raw;
+   v3_sub( inf->co, localplayer.rb.co, raw );
+
+   m3x3_mulv( mtx, raw, player_skate.grind_vec );
+   v3_normalize( player_skate.grind_vec );
+   v3_copy( inf->dir, player_skate.grind_dir );
+}
+
+static enum skate_activity skate_availible_grind(void){
+   struct player_skate_state *state = &player_skate.state;
+
+   if( state->grind_cooldown > 100 ){
+      vg_fatal_error( "wth!\n" );
+   }
+
+   /* debounces this state manager a little bit */
+   if( state->grind_cooldown ){
+      state->grind_cooldown --;
+      return k_skate_activity_undefined;
+   }
+
+   struct grind_info inf_back50,
+                     inf_front50,
+                     inf_slide;
+
+   int res_back50  = 0,
+       res_front50 = 0,
+       res_slide   = 0;
+
+   int allow_back  = 1,
+       allow_front = 1;
+
+   v2f steer;
+   joystick_state( k_srjoystick_steer, steer );
+
+   if( state->activity == k_skate_activity_grind_5050 || 
+       state->activity == k_skate_activity_grind_back50 ||
+       state->activity == k_skate_activity_grind_front50 )
+   {
+      float tilt = steer[1];
+
+      if( fabsf(tilt) >= 0.25f ){
+         v3f raw = {0.0f,0.0f,tilt};
+         m3x3_mulv( localplayer.rb.to_world, raw, raw );
+
+         float way = tilt * vg_signf( v3_dot( raw, localplayer.rb.v ) );
+
+         if( way < 0.0f ) allow_front = 0;
+         else allow_back = 0;
+      }
+   }
+
+   if( state->activity == k_skate_activity_grind_boardslide ){
+      res_slide = skate_boardslide_renew( &inf_slide );
+   }
+   else if( state->activity == k_skate_activity_grind_back50 ){
+      res_back50  = skate_grind_truck_renew( 1.0f, &inf_back50 );
+
+      if( allow_front )
+         res_front50 = skate_grind_truck_entry( -1.0f, &inf_front50 );
+   }
+   else if( state->activity == k_skate_activity_grind_front50 ){
+      res_front50 = skate_grind_truck_renew( -1.0f, &inf_front50 );
+
+      if( allow_back )
+         res_back50  = skate_grind_truck_entry(  1.0f, &inf_back50 );
+   }
+   else if( state->activity == k_skate_activity_grind_5050 ){
+      if( allow_front )
+         res_front50 = skate_grind_truck_renew( -1.0f, &inf_front50 );
+      if( allow_back )
+         res_back50  = skate_grind_truck_renew(  1.0f, &inf_back50 );
+   }
+   else{
+      res_slide   = skate_boardslide_entry( &inf_slide );
+
+      if( allow_back )
+         res_back50  = skate_grind_truck_entry(  1.0f, &inf_back50 );
+
+      if( allow_front )
+         res_front50 = skate_grind_truck_entry( -1.0f, &inf_front50 );
+
+      if( res_back50 != res_front50 ){
+         int wants_to_do_that = fabsf(steer[1]) >= 0.25f;
+
+         res_back50  &= wants_to_do_that;
+         res_front50 &= wants_to_do_that;
+      }
+   }
+
+   const enum skate_activity table[] =
+   {                                      /* slide | back | front */
+      k_skate_activity_undefined,         /* 0       0      0     */
+      k_skate_activity_grind_front50,     /* 0       0      1     */
+      k_skate_activity_grind_back50,      /* 0       1      0     */
+      k_skate_activity_grind_5050,        /* 0       1      1     */
+
+      /* slide has priority always */
+      k_skate_activity_grind_boardslide,  /* 1       0      0     */
+      k_skate_activity_grind_boardslide,  /* 1       0      1     */
+      k_skate_activity_grind_boardslide,  /* 1       1      0     */
+      k_skate_activity_grind_boardslide,  /* 1       1      1     */
+   }
+   , new_activity = table[ res_slide << 2 | res_back50 << 1 | res_front50 ];
+
+   if(      new_activity == k_skate_activity_undefined ){
+      if( state->activity >= k_skate_activity_grind_any ){
+         state->grind_cooldown = 15;
+         state->surface_cooldown = 10;
+      }
+   }
+   else if( new_activity == k_skate_activity_grind_boardslide ){
+      skate_boardslide_apply( &inf_slide );
+   }
+   else if( new_activity == k_skate_activity_grind_back50 ){
+      if( state->activity != k_skate_activity_grind_back50 )
+         skate_store_grind_vec( &inf_back50 );
+
+      skate_grind_truck_apply(  1.0f, &inf_back50, 1.0f );
+   }
+   else if( new_activity == k_skate_activity_grind_front50 ){
+      if( state->activity != k_skate_activity_grind_front50 )
+         skate_store_grind_vec( &inf_front50 );
+
+      skate_grind_truck_apply( -1.0f, &inf_front50, 1.0f );
+   }
+   else if( new_activity == k_skate_activity_grind_5050 )
+      skate_5050_apply( &inf_front50, &inf_back50 );
+
+   return new_activity;
+}
+
+static void player__skate_update(void){
+   struct player_skate_state *state = &player_skate.state;
+   world_instance *world = world_current_instance();
+
+   if( world->water.enabled ){
+      if( localplayer.rb.co[1]+0.25f < world->water.height ){
+         player__networked_sfx( k_player_subsystem_walk, 32, 
+                                k_player_walk_soundeffect_splash,
+                                localplayer.rb.co, 1.0f );
+         player__skate_kill_audio();
+         player__dead_transition();
+         return;
+      }
+   }
+
+   v3_copy( localplayer.rb.co, state->prev_pos );
+   state->activity_prev = state->activity;
+   v3f normal_total;
+   v3_zero( normal_total );
+
+   struct board_collider
+   {
+      v3f   pos;
+      float radius;
+
+      u32   colour;
+
+      enum  board_collider_state
+      {
+         k_collider_state_default,
+         k_collider_state_disabled,
+         k_collider_state_colliding
+      }
+      state;
+   }
+   wheels[] =
+   {
+      { 
+         { 0.0f, 0.0f,    -k_board_length }, 
+         .radius = k_board_radius,
+         .colour = VG__RED
+      },
+      { 
+         { 0.0f, 0.0f,     k_board_length }, 
+         .radius = k_board_radius,
+         .colour = VG__GREEN
+      }
+   };
+
+   float slap = 0.0f;
+
+   if( state->activity <= k_skate_activity_air_to_grind ){
+      float min_dist = 0.6f;
+      for( int i=0; i<2; i++ ){
+         v3f wpos, closest;
+         m4x3_mulv( localplayer.rb.to_world, wheels[i].pos, wpos );
+
+         if( bh_closest_point( world->geo_bh, wpos, closest, min_dist ) != -1 ){
+            min_dist = vg_minf( min_dist, v3_dist( closest, wpos ) );
+         }
+      }
+      min_dist -= 0.2f;
+      float vy = vg_maxf( 0.0f, localplayer.rb.v[1] );
+      slap = vg_clampf( (min_dist/0.5f) + vy, 0.0f, 1.0f )*0.3f;
+   }
+   state->slap = vg_lerpf( state->slap, slap, 10.0f*k_rb_delta );
+
+   wheels[0].pos[1] = state->slap;
+   wheels[1].pos[1] = state->slap;
+
+
+   const int k_wheel_count = 2;
+
+   player_skate.substep = k_rb_delta;
+   player_skate.substep_delta = player_skate.substep;
+   player_skate.limit_count = 0;
+
+   int substep_count = 0;
+
+   v3_zero( player_skate.surface_picture );
+
+   int prev_contacts[2];
+
+   for( int i=0; i<k_wheel_count; i++ ){
+      wheels[i].state = k_collider_state_default;
+      prev_contacts[i] = player_skate.wheel_contacts[i];
+   }
+
+   /* check if we can enter or continue grind */
+   enum skate_activity grindable_activity = skate_availible_grind();
+   if( grindable_activity != k_skate_activity_undefined ){
+      state->activity = grindable_activity;
+      goto grinding;
+   }
+
+   int contact_count = 0;
+   for( int i=0; i<2; i++ ){
+      v3f normal, axel;
+      v3_copy( localplayer.rb.to_world[0], axel );
+
+      if( skate_compute_surface_alignment( wheels[i].pos, 
+                                           wheels[i].colour, normal, axel ) )
+      {
+         rb_effect_spring_target_vector( &localplayer.rb, 
+                                          localplayer.rb.to_world[0],
+                                          axel,
+                                          k_surface_spring, k_surface_dampener,
+                                          player_skate.substep_delta );
+
+         v3_add( normal, player_skate.surface_picture, 
+                 player_skate.surface_picture );
+         contact_count ++;
+         player_skate.wheel_contacts[i] = 1;
+      }
+      else{
+         player_skate.wheel_contacts[i] = 0;
+      }
+
+      m3x3_mulv( localplayer.rb.to_local, axel, player_skate.truckv0[i] );
+   }
+
+   if( state->surface_cooldown ){
+      state->surface_cooldown --;
+      contact_count = 0;
+   }
+
+   if( (prev_contacts[0]+prev_contacts[1] == 1) && (contact_count == 2) ){
+      for( int i=0; i<2; i++ ){
+         if( !prev_contacts[i] ){
+            v3f co;
+            m4x3_mulv( localplayer.rb.to_world, wheels[i].pos, co );
+            player__networked_sfx( k_player_subsystem_skate, 32, 
+                                   k_player_skate_soundeffect_tap,
+                                   localplayer.rb.co, 0.75f );
+         }
+      }
+   }
+
+   if( contact_count ){
+      state->activity = k_skate_activity_ground;
+      state->gravity_bias = k_gravity;
+      v3_normalize( player_skate.surface_picture );
+
+      skate_apply_friction_model();
+      skate_weight_distribute();
+   }
+   else{
+      if( state->activity > k_skate_activity_air_to_grind )
+         state->activity = k_skate_activity_air;
+
+      v3_zero( player_skate.weight_distribution );
+      skate_apply_air_model();
+   }
+
+grinding:;
+
+   if( state->activity == k_skate_activity_grind_back50 )
+      wheels[1].state = k_collider_state_disabled;
+   if( state->activity == k_skate_activity_grind_front50 )
+      wheels[0].state = k_collider_state_disabled;
+   if( state->activity == k_skate_activity_grind_5050 ){
+      wheels[0].state = k_collider_state_disabled;
+      wheels[1].state = k_collider_state_disabled;
+   }
+
+   /* all activities */
+   skate_apply_steering_model();
+   skate_adjust_up_direction();
+   skate_apply_cog_model();
+   skate_apply_jump_model();
+   skate_apply_grab_model();
+   skate_apply_trick_model();
+   skate_apply_pump_model();
+
+begin_collision:;
+
+   /*
+    * Phase 0: Continous collision detection
+    * --------------------------------------------------------------------------
+    */
+
+   v3f head_wp0, head_wp1, start_co;
+   m4x3_mulv( localplayer.rb.to_world, state->head_position, head_wp0 );
+   v3_copy( localplayer.rb.co, start_co );
+
+   /* calculate transform one step into future */
+   v3f future_co;
+   v4f future_q;
+   v3_muladds( localplayer.rb.co, localplayer.rb.v, player_skate.substep, 
+               future_co );
+
+   if( v3_length2( localplayer.rb.w ) > 0.0f ){
+      v4f rotation;
+      v3f axis;
+      v3_copy( localplayer.rb.w, axis );
+      
+      float mag = v3_length( axis );
+      v3_divs( axis, mag, axis );
+      q_axis_angle( rotation, axis, mag*player_skate.substep );
+      q_mul( rotation, localplayer.rb.q, future_q );
+      q_normalize( future_q );
+   }
+   else
+      v4_copy( localplayer.rb.q, future_q );
+
+   v3f future_cg, current_cg, cg_offset;
+   q_mulv( localplayer.rb.q, player_skate.weight_distribution, current_cg );
+   q_mulv( future_q, player_skate.weight_distribution, future_cg );
+   v3_sub( future_cg, current_cg, cg_offset );
+
+   /* calculate the minimum time we can move */
+   float max_time = player_skate.substep;
+
+   for( int i=0; i<k_wheel_count; i++ ){
+      if( wheels[i].state == k_collider_state_disabled )
+         continue;
+
+      v3f current, future, r_cg;
+      
+      q_mulv( future_q, wheels[i].pos, future );
+      v3_add( future, future_co, future );
+      v3_add( cg_offset, future, future );
+
+      q_mulv( localplayer.rb.q, wheels[i].pos, current );
+      v3_add( current, localplayer.rb.co, current );
+      
+      float t;
+      v3f n;
+
+      float cast_radius = wheels[i].radius - k_penetration_slop * 2.0f;
+      if( spherecast_world( world, current, future, cast_radius, &t, n,
+                            k_material_flag_walking ) != -1)
+         max_time = vg_minf( max_time, t * player_skate.substep );
+   }
+
+   /* clamp to a fraction of delta, to prevent locking */
+   float rate_lock = substep_count;
+   rate_lock *= k_rb_delta * 0.1f;
+   rate_lock *= rate_lock;
+
+   max_time = vg_maxf( max_time, rate_lock );
+   player_skate.substep_delta = max_time;
+
+   /* integrate */
+   v3_muladds( localplayer.rb.co, localplayer.rb.v, 
+               player_skate.substep_delta, localplayer.rb.co );
+   if( v3_length2( localplayer.rb.w ) > 0.0f ){
+      v4f rotation;
+      v3f axis;
+      v3_copy( localplayer.rb.w, axis );
+      
+      float mag = v3_length( axis );
+      v3_divs( axis, mag, axis );
+      q_axis_angle( rotation, axis, mag*player_skate.substep_delta );
+      q_mul( rotation, localplayer.rb.q, localplayer.rb.q );
+      q_normalize( localplayer.rb.q );
 
-   s->state.activity = k_skate_activity_air;
-   s->state.activity_prev = k_skate_activity_air;
+      q_mulv( localplayer.rb.q, player_skate.weight_distribution, future_cg );
+      v3_sub( current_cg, future_cg, cg_offset );
+      v3_add( localplayer.rb.co, cg_offset, localplayer.rb.co );
+   }
+
+   rb_update_transform( &localplayer.rb );
+   localplayer.rb.v[1] += -state->gravity_bias * player_skate.substep_delta;
+
+   player_skate.substep -= player_skate.substep_delta;
+
+   rb_ct manifold[128];
+   int manifold_len = 0;
+   /*
+    * Phase -1: head detection
+    * --------------------------------------------------------------------------
+    */
+   m4x3_mulv( localplayer.rb.to_world, state->head_position, head_wp1 );
+
+   float t;
+   v3f n;
+   if( (v3_dist2( head_wp0, head_wp1 ) > 0.001f) &&
+       (spherecast_world( world, head_wp0, head_wp1, 0.2f, &t, n,
+                          k_material_flag_walking ) != -1) )
+   {
+      v3_lerp( start_co, localplayer.rb.co, t, localplayer.rb.co );
+      rb_update_transform( &localplayer.rb );
+
+      player__skate_kill_audio();
+      player__dead_transition();
+      return;
+   }
+
+   /*
+    * Phase 1: Regular collision detection
+    * --------------------------------------------------------------------------
+    */
+
+   for( int i=0; i<k_wheel_count; i++ ){
+      if( wheels[i].state == k_collider_state_disabled )
+         continue;
+
+      m4x3f mtx;
+      m3x3_identity( mtx );
+      m4x3_mulv( localplayer.rb.to_world, wheels[i].pos, mtx[3] );
+      
+      rb_sphere collider = { .radius = wheels[i].radius };
+
+      rb_ct *man = &manifold[ manifold_len ];
+
+      int l = skate_collide_smooth( mtx, &collider, man );
+      if( l )
+         wheels[i].state = k_collider_state_colliding;
+
+      manifold_len += l;
+   }
+
+   float grind_radius = k_board_radius * 0.75f;
+   rb_capsule capsule = { .height = (k_board_length+0.2f)*2.0f, 
+                          .radius=grind_radius };
+   m4x3f mtx;
+   v3_muls( localplayer.rb.to_world[0],  1.0f, mtx[0] );
+   v3_muls( localplayer.rb.to_world[2], -1.0f, mtx[1] );
+   v3_muls( localplayer.rb.to_world[1],  1.0f, mtx[2] );
+   v3_muladds( localplayer.rb.to_world[3], localplayer.rb.to_world[1], 
+               grind_radius + k_board_radius*0.25f+state->slap, mtx[3] );
+
+   rb_ct *cman = &manifold[manifold_len];
+
+   int l = rb_capsule__scene( mtx, &capsule, NULL, &world->rb_geo.inf.scene,
+                              cman, k_material_flag_walking );
+
+   /* weld joints */
+   for( int i=0; i<l; i ++ )
+      cman[l].type = k_contact_type_edge;
+   rb_manifold_filter_joint_edges( cman, l, 0.03f );
+   l = rb_manifold_apply_filtered( cman, l );
+
+   manifold_len += l;
+
+   if( vg_lines.draw )
+      vg_line_capsule( mtx, capsule.radius, capsule.height, VG__WHITE );
+
+   /* add limits */
+   if( state->activity >= k_skate_activity_grind_any ){
+      for( int i=0; i<player_skate.limit_count; i++ ){
+         struct grind_limit *limit = &player_skate.limits[i];
+         rb_ct *ct = &manifold[ manifold_len ++ ];
+         m4x3_mulv( localplayer.rb.to_world, limit->ra, ct->co );
+         m3x3_mulv( localplayer.rb.to_world, limit->n, ct->n );
+         ct->p = limit->p;
+         ct->type = k_contact_type_default;
+      }
+   }
+
+   /* 
+    * Phase 3: Dynamics
+    * --------------------------------------------------------------------------
+    */
+
+
+   v3f world_cog;
+   m4x3_mulv( localplayer.rb.to_world, 
+              player_skate.weight_distribution, world_cog );
+   vg_line_point( world_cog, 0.02f, VG__BLACK );
+
+   for( int i=0; i<manifold_len; i ++ ){
+      rb_prepare_contact( &manifold[i], player_skate.substep_delta );
+      rb_debug_contact( &manifold[i] );
+   }
+
+   /* yes, we are currently rebuilding mass matrices every frame. too bad! */
+   v3f extent = { k_board_width*10.0f, 0.1f, k_board_length };
+   float ex2 = k_board_interia*extent[0]*extent[0],
+         ey2 = k_board_interia*extent[1]*extent[1],
+         ez2 = k_board_interia*extent[2]*extent[2];
+
+   float mass = 2.0f * (extent[0]*extent[1]*extent[2]);
+   float inv_mass = 1.0f/mass;
+
+   v3f I;
+   I[0] = ((1.0f/12.0f) * mass * (ey2+ez2));
+   I[1] = ((1.0f/12.0f) * mass * (ex2+ez2));
+   I[2] = ((1.0f/12.0f) * mass * (ex2+ey2));
+
+   m3x3f iI;
+   m3x3_identity( iI );
+   iI[0][0] = I[0];
+   iI[1][1] = I[1];
+   iI[2][2] = I[2];
+   m3x3_inv( iI, iI );
+
+   m3x3f iIw;
+   m3x3_mul( iI, localplayer.rb.to_local, iIw );
+   m3x3_mul( localplayer.rb.to_world, iIw, iIw );
+
+   for( int j=0; j<10; j++ ){
+      for( int i=0; i<manifold_len; i++ ){
+         /* 
+          * regular dance; calculate velocity & total mass, apply impulse.
+          */
+
+         struct contact *ct = &manifold[i];
+         
+         v3f rv, delta;
+         v3_sub( ct->co, world_cog, delta ); 
+         v3_cross( localplayer.rb.w, delta, rv );
+         v3_add( localplayer.rb.v, rv, rv );
+
+         v3f raCn;
+         v3_cross( delta, ct->n, raCn );
+
+         v3f raCnI, rbCnI;
+         m3x3_mulv( iIw, raCn, raCnI );
+
+         float normal_mass = 1.0f / (inv_mass + v3_dot(raCn,raCnI)),
+               vn = v3_dot( rv, ct->n ),
+               lambda = normal_mass * ( -vn );
+
+         float temp = ct->norm_impulse;
+         ct->norm_impulse = vg_maxf( temp + lambda, 0.0f );
+         lambda = ct->norm_impulse - temp;
+
+         v3f impulse;
+         v3_muls( ct->n, lambda, impulse );
+
+         v3_muladds( normal_total, impulse, inv_mass, normal_total );
+         v3_muladds( localplayer.rb.v, impulse, inv_mass, localplayer.rb.v );
+         v3_cross( delta, impulse, impulse );
+         m3x3_mulv( iIw, impulse, impulse );
+         v3_add( impulse, localplayer.rb.w, localplayer.rb.w );
+
+         v3_cross( localplayer.rb.w, delta, rv );
+         v3_add( localplayer.rb.v, rv, rv );
+         vn = v3_dot( rv, ct->n );
+      }
+   }
+
+   v3f dt;
+   rb_depenetrate( manifold, manifold_len, dt );
+   v3_add( dt, localplayer.rb.co, localplayer.rb.co );
+   rb_update_transform( &localplayer.rb );
+
+   substep_count ++;
+
+   if( player_skate.substep >= 0.0001f )
+      goto begin_collision;      /* again! */
+
+   /* 
+    * End of collision and dynamics routine
+    * --------------------------------------------------------------------------
+    */
+
+   f32 nforce = v3_length(normal_total);
+   if( nforce > 4.0f ){
+      if( nforce > 17.6f ){
+         v3_muladds( localplayer.rb.v, normal_total, -1.0f, localplayer.rb.v );
+         player__dead_transition();
+         player__skate_kill_audio();
+         return;
+      }
+
+      f32 amt = k_cam_punch;
+      if( localplayer.cam_control.camera_mode == k_cam_firstperson ){
+         amt *= 0.25f;
+      }
+
+      v3_muladds( localplayer.cam_land_punch_v, normal_total, amt,
+                  localplayer.cam_land_punch_v );
+   }
+
+   player_skate.surface = k_surface_prop_concrete;
+
+   for( int i=0; i<manifold_len; i++ ){
+      rb_ct *ct = &manifold[i];
+      struct world_surface *surf = world_contact_surface( world, ct );
+
+      if( surf->info.surface_prop > player_skate.surface )
+         player_skate.surface = surf->info.surface_prop;
+   }
+
+   for( int i=0; i<k_wheel_count; i++ ){
+      m4x3f mtx;
+      m3x3_copy( localplayer.rb.to_world, mtx );
+      m4x3_mulv( localplayer.rb.to_world, wheels[i].pos, mtx[3] );
+      vg_line_sphere( mtx, wheels[i].radius,
+                      (u32[]){ VG__WHITE, VG__BLACK, 
+                            wheels[i].colour }[ wheels[i].state ]);
+   }
+
+   skate_integrate();
+   vg_line_point( state->cog, 0.02f, VG__WHITE );
+
+   u32 id = world_intersect_gates( world, localplayer.rb.co, state->prev_pos );
+
+   if( id ){
+      ent_gate *gate = mdl_arritm( &world->ent_gate, mdl_entity_id_id(id) );
+
+      m4x3_mulv( gate->transport, localplayer.rb.co, localplayer.rb.co );
+      m3x3_mulv( gate->transport, localplayer.rb.v,  localplayer.rb.v );
+      m4x3_mulv( gate->transport, state->cog,   state->cog );
+      m3x3_mulv( gate->transport, state->cog_v, state->cog_v );
+      m3x3_mulv( gate->transport, state->throw_v, state->throw_v );
+      m3x3_mulv( gate->transport, state->head_position,
+                                  state->head_position );
+      m3x3_mulv( gate->transport, state->up_dir, state->up_dir );
+
+      v4f transport_rotation;
+      m3x3_q( gate->transport, transport_rotation );
+      q_mul( transport_rotation, localplayer.rb.q, localplayer.rb.q );
+      q_mul( transport_rotation, state->smoothed_rotation,
+                                 state->smoothed_rotation );
+      rb_update_transform( &localplayer.rb );
+      player__pass_gate( id );
+   }
+
+   /* FIXME: Rate limit */
+   static int stick_frames = 0;
+
+   if( state->activity >= k_skate_activity_ground )
+      stick_frames ++;
+   else
+      stick_frames = 0;
+
+   if( stick_frames > 5 ) stick_frames =  5;
+
+   if( stick_frames == 4 ){
+      if( state->activity == k_skate_activity_ground ){
+         if( (fabsf(state->slip) > 0.75f) ){
+            player__networked_sfx( k_player_subsystem_skate, 128, 
+                                   k_player_skate_soundeffect_land_bad,
+                                   localplayer.rb.co, 0.6f );
+         }
+         else{
+            player__networked_sfx( k_player_subsystem_skate, 128, 
+                                   k_player_skate_soundeffect_land_good,
+                                   localplayer.rb.co, 1.0f );
+         }
+      }
+      else if( player_skate.surface == k_surface_prop_metal ){
+         player__networked_sfx( k_player_subsystem_skate, 128, 
+                                k_player_skate_soundeffect_grind_metal,
+                                localplayer.rb.co, 1.0f );
+      }
+      else{
+         player__networked_sfx( k_player_subsystem_skate, 128, 
+                                k_player_skate_soundeffect_grind_wood,
+                                localplayer.rb.co, 1.0f );
+      }
+   } else if( stick_frames == 0 ){
+      /* TODO: EXIT SOUNDS */
+   }
+
+   if( (state->activity_prev < k_skate_activity_grind_any) && 
+       (state->activity >= k_skate_activity_grind_any) ){
+      state->velocity_limit = v3_length( localplayer.rb.v )*1.0f;
+      state->grind_y_start = localplayer.rb.co[1];
+   }
+
+   if( state->activity >= k_skate_activity_grind_any ){
+      f32 dy = localplayer.rb.co[1] - state->grind_y_start;
+      if( dy < 0.0f ){
+         state->velocity_limit += -dy*0.2f;
+      }
+      state->grind_y_start = localplayer.rb.co[1];
+
+
+      f32 speed_end = v3_length( localplayer.rb.v );
+      if( speed_end > state->velocity_limit ){
+         v3_muls( localplayer.rb.v, state->velocity_limit/speed_end, 
+                  localplayer.rb.v );
+      }
+   }
+}
+
+static void player__skate_im_gui(void){
+   struct player_skate_state *state = &player_skate.state;
+   player__debugtext( 1, "V:  %5.2f %5.2f %5.2f",localplayer.rb.v[0],
+                                                localplayer.rb.v[1],
+                                                localplayer.rb.v[2] );
+   player__debugtext( 1, "CO: %5.2f %5.2f %5.2f",localplayer.rb.co[0],
+                                                localplayer.rb.co[1],
+                                                localplayer.rb.co[2] );
+   player__debugtext( 1, "W:  %5.2f %5.2f %5.2f",localplayer.rb.w[0],
+                                                localplayer.rb.w[1],
+                                                localplayer.rb.w[2] );
+
+   const char *activity_txt[] = {
+      "air",
+      "air_to_grind",
+      "ground",
+      "undefined (INVALID)",
+      "grind_any (INVALID)",
+      "grind_boardslide",
+      "grind_metallic (INVALID)",
+      "grind_back50",
+      "grind_front50",
+      "grind_5050"
+   };
+
+   player__debugtext( 1, "activity: %s", activity_txt[state->activity] );
+#if 0
+   player__debugtext( 1, "steer_s: %5.2f %5.2f [%.2f %.2f]",
+                        state->steerx_s, state->steery_s,
+                        k_steer_ground, k_steer_air );
+#endif
+   player__debugtext( 1, "flip: %.4f %.4f", state->flip_rate, 
+                                             state->flip_time );
+   player__debugtext( 1, "trickv: %.2f %.2f %.2f", 
+                           state->trick_vel[0],
+                           state->trick_vel[1],
+                           state->trick_vel[2] );
+   player__debugtext( 1, "tricke: %.2fs %.2f %.2f %.2f", 
+                           state->trick_time,
+                           state->trick_euler[0],
+                           state->trick_euler[1],
+                           state->trick_euler[2] );
+}
+
+static void player__skate_animate(void){
+   struct player_skate_state *state = &player_skate.state;
+   struct player_skate_animator *animator = &player_skate.animator;
+
+   /* Head */
+   float kheight = 2.0f,
+         kleg = 0.6f;
+
+   v3_zero( animator->offset );
+
+   v3f cog_local, cog_ideal;
+   m4x3_mulv( localplayer.rb.to_local, state->cog, cog_local );
+
+   v3_copy( state->up_dir, cog_ideal );
+   v3_normalize( cog_ideal );
+   m3x3_mulv( localplayer.rb.to_local, cog_ideal, cog_ideal );
+
+   v3_sub( cog_ideal, cog_local, animator->offset );
+
+   v3_muls( animator->offset, 4.0f, animator->offset );
+   animator->offset[1] *= -1.0f;
+
+   float curspeed  = v3_length( localplayer.rb.v ),
+         kickspeed = vg_clampf( curspeed*(1.0f/40.0f), 0.0f, 1.0f ),
+         kicks     = (vg_randf64(&vg.rand)-0.5f)*2.0f*kickspeed,
+         sign      = vg_signf( kicks );
+
+   animator->wobble[0] = vg_lerpf( animator->wobble[0], kicks*kicks*sign, 
+                                   6.0f*vg.time_delta);
+   animator->wobble[1] = vg_lerpf( animator->wobble[1], animator->wobble[0], 
+                                   2.4f*vg.time_delta);
+
+   animator->offset[0] *= 0.26f;
+   animator->offset[0] += animator->wobble[1]*3.0f;
+
+   animator->offset[1] *= -0.3f;
+   animator->offset[2] *= 0.01f;
+
+   animator->offset[0]=vg_clampf(animator->offset[0],-0.8f,0.8f)*
+                                 (1.0f-fabsf(animator->slide)*0.9f);
+   animator->offset[1]=vg_clampf(animator->offset[1],-0.5f,0.0f);
+
+   v3f cam_offset;
+   v3_mul( animator->offset, (v3f){1.0f,0.3f,1.0f}, cam_offset );
+   v3_copy( cam_offset, localplayer.cam_control.tpv_offset_extra );
+
+   /* localized vectors */
+   m4x3_mulv( localplayer.rb.to_local, state->cog, animator->local_cog );
+
+   /* 
+    * Animation blending
+    * ===========================================
+    */
+   
+   /* sliding */
+   {
+      float desired = 0.0f;
+      if( state->activity == k_skate_activity_ground )
+         desired = vg_clampf( fabsf( state->slip ), 0.0f, 1.0f );
+
+      animator->slide = vg_lerpf( animator->slide, desired, 2.4f*vg.time_delta);
+   }
+   
+   /* movement information */
+   int iair = state->activity <= k_skate_activity_air_to_grind;
+
+   float dirz = state->reverse > 0.0f? 0.0f: 1.0f,
+         dirx = state->slip < 0.0f?    0.0f: 1.0f,
+         fly  = iair?                    1.0f: 0.0f,
+         wdist= player_skate.weight_distribution[2] / k_board_length;
+
+   if( state->activity >= k_skate_activity_grind_any )
+      wdist = 0.0f;
+
+   animator->z      = vg_lerpf( animator->z,      dirz,  2.4f*vg.time_delta );
+   animator->x      = vg_lerpf( animator->x,      dirx,  0.6f*vg.time_delta );
+   animator->fly    = vg_lerpf( animator->fly,    fly,   3.4f*vg.time_delta );
+   animator->weight = vg_lerpf( animator->weight, wdist, 9.0f*vg.time_delta );
+
+   float stand = 1.0f - vg_clampf( curspeed * 0.03f, 0.0f, 1.0f );
+   animator->stand  = vg_lerpf( animator->stand, stand, 6.0f*vg.time_delta );
+   animator->reverse = state->reverse;
+
+   if( fabsf(state->slip) > 0.3f ){
+      f32 slide_x = v3_dot(localplayer.rb.v, localplayer.rb.to_world[0]);
+      state->delayed_slip_dir = vg_signf(slide_x);
+   }
+
+   /* grinding */
+   f32 grind=state->activity >= k_skate_activity_grind_any? 1.0f: 0.0f;
+   animator->grind = vg_lerpf( animator->grind,  grind, 5.0f*vg.time_delta );
+
+   f32 grind_frame = 0.5f;
+
+   if( state->activity == k_skate_activity_grind_front50 )
+      grind_frame = 0.0f;
+   else if( state->activity == k_skate_activity_grind_back50 )
+      grind_frame = 1.0f;
+
+   animator->grind_balance = vg_lerpf( animator->grind_balance, grind_frame, 
+                                5.0f*vg.time_delta );
+   animator->activity = state->activity;
+
+   /* pushing */
+   animator->push_time = vg.time - state->start_push;
+   animator->push = vg_lerpf( animator->push, 
+                              (vg.time - state->cur_push) < 0.125,
+                              6.0f*vg.time_delta );
+
+   /* jumping */
+   animator->jump_charge = state->jump_charge;
+   animator->jump = vg_lerpf( animator->jump, animator->jump_charge, 
+                              8.4f*vg.time_delta );
+
+   /* trick setup */
+   animator->jump_dir = state->jump_dir;
+   f32 jump_start_frame = 14.0f/30.0f;
+   animator->jump_time = animator->jump_charge * jump_start_frame;
+   f32 jump_frame = (vg.time - state->jump_time) + jump_start_frame;
+   if( jump_frame >= jump_start_frame && jump_frame <= (40.0f/30.0f) )
+      animator->jump_time = jump_frame;
+
+   /* trick */
+   float jump_t = vg.time-state->jump_time;
+   float k=17.0f;
+   float h = k*jump_t;
+   float extra = h*exp(1.0-h) * (state->jump_dir?1.0f:-1.0f);
+         extra *= state->slap * 4.0f;
+
+   v3_add( state->trick_euler, state->trick_residuald, 
+            animator->board_euler );
+   v3_muls( animator->board_euler, VG_TAUf, animator->board_euler );
+
+   animator->board_euler[0] *= 0.5f;
+   animator->board_euler[1] += extra;
+   animator->trick_type = state->trick_type;
+
+   /* board lean */
+   f32 lean1, lean2 = animator->steer[0] * animator->reverse * -0.36f,
+       lean;
+
+   lean1 = animator->slide * animator->delayed_slip_dir;
+   if( fabsf(lean1)>fabsf(lean2) ) lean = lean1;
+   else                            lean = lean2;
+
+   if( ((int)roundf(animator->board_euler[0]/VG_PIf)) % 2 ) lean = -lean;
+   lean = vg_clampf( lean, -1.0f, 1.0f );
+   animator->board_lean = 
+      vg_lerpf(animator->board_lean, lean, vg.time_delta*18.0f);
+
+   /* feet placement */
+   struct player_board *board = 
+      addon_cache_item_if_loaded( k_addon_type_board,
+                                  localplayer.board_view_slot );
+   if( board ){
+      if( animator->weight > 0.0f ){
+         animator->foot_offset[0] = 
+            board->truck_positions[k_board_truck_back][2]+0.3f;
+      }
+      else{
+         animator->foot_offset[1] = 
+            board->truck_positions[k_board_truck_front][2]-0.3f;
+      }
+   }
+
+   f32 slapm = vg_maxf( 1.0f-v3_length2( state->trick_vel ), 0.0f );
+   animator->slap = state->slap;
+   animator->subslap = vg_lerpf( animator->subslap, slapm, 
+                                 vg.time_delta*10.0f );
+
+#if 0
+   f32 l = ((state->activity < k_skate_activity_ground) &&
+             v3_length2(state->trick_vel) > 0.1f )? 1: 0;
+   animator->trick_foot = vg_lerpf( animator->trick_foot, l, 
+                                    8.4f*vg.time_delta );
+#endif
+
+   animator->trick_foot = vg_exp_impulse( state->trick_time, 5.0f );
+
+   /* grab */
+   v2f grab_input;
+   joystick_state( k_srjoystick_grab, grab_input );
+   v2_add( state->grab_mouse_delta, grab_input, grab_input );
+
+   if( v2_length2( grab_input ) <= 0.001f ) grab_input[0] = -1.0f;
+   else v2_normalize_clamp( grab_input );
+   v2_lerp( animator->grab, grab_input, 2.4f*vg.time_delta, animator->grab );
+   animator->grabbing = state->grabbing;
+
+   /* steer */
+   joystick_state( k_srjoystick_steer, animator->steer );
+
+   animator->airdir = vg_lerpf( animator->airdir, -animator->steer[0],
+                                2.4f*vg.time_delta );
+      
+
+   /* flip angle */
+   if( (state->activity <= k_skate_activity_air_to_grind) &&
+       (fabsf(state->flip_rate) > 0.01f) ){
+      float substep = vg.time_fixed_extrapolate;
+      float t     = state->flip_time+state->flip_rate*substep*k_rb_delta;
+            sign  = vg_signf( t );
+
+      t  = 1.0f - vg_minf( 1.0f, fabsf( t * 1.1f ) );
+      t  = sign * (1.0f-t*t);
+
+      f32 angle = vg_clampf( t, -1.0f, 1.0f ) * VG_TAUf,
+          distm = state->land_dist * fabsf(state->flip_rate) * 3.0f,
+          blend = vg_clampf( 1.0f-distm, 0.0f, 1.0f );
+      angle = vg_lerpf( angle, vg_signf(state->flip_rate)*VG_TAUf, blend );
+      q_axis_angle( animator->qflip, state->flip_axis, angle );
+   }
+   else 
+      q_identity( animator->qflip );
+
+   /* counter-rotation */
+   if( v3_length2( state->up_dir ) > 0.001f ){
+      v4_lerp( state->smoothed_rotation, localplayer.rb.q, 
+               2.0f*vg.time_frame_delta,
+               state->smoothed_rotation );
+      q_normalize( state->smoothed_rotation );
+
+      v3f yaw_smooth = {1.0f,0.0f,0.0f};
+      q_mulv( state->smoothed_rotation, yaw_smooth, yaw_smooth );
+      m3x3_mulv( localplayer.rb.to_local, yaw_smooth, yaw_smooth );
+      yaw_smooth[1] = 0.0f;
+      v3_normalize( yaw_smooth );
+
+      f32 yaw_counter_rotate  = yaw_smooth[0];
+          yaw_counter_rotate  = vg_maxf( 0.7f, yaw_counter_rotate );
+          yaw_counter_rotate  = acosf( yaw_counter_rotate );
+          yaw_counter_rotate *= 1.0f-animator->fly;
+
+      v3f ndir;
+      m3x3_mulv( localplayer.rb.to_local, state->up_dir, ndir );
+      v3_normalize( ndir );
+
+      v3f up = { 0.0f, 1.0f, 0.0f };
+      float a = v3_dot( ndir, up );
+      a = acosf( vg_clampf( a, -1.0f, 1.0f ) );
+
+      v3f axis;
+      v4f qcounteryaw, qfixup;
+      
+      v3_cross( up, ndir, axis );
+      q_axis_angle( qfixup, axis, a*2.0f );
+
+      v3_cross( (v3f){1.0f,0.0f,0.0f}, yaw_smooth, axis );
+      q_axis_angle( qcounteryaw, axis, yaw_counter_rotate );
+
+      q_mul( qcounteryaw, qfixup, animator->qfixuptotal );
+      q_normalize( animator->qfixuptotal );
+
+      v3f p1, p2;
+      m3x3_mulv( localplayer.rb.to_world, up, p1 );
+      m3x3_mulv( localplayer.rb.to_world, ndir, p2 );
+
+      vg_line_arrow( localplayer.rb.co, p1, 0.5f, VG__PINK );
+      vg_line_arrow( localplayer.rb.co, p2, 0.5f, VG__PINK );
+   }
+   else q_identity( animator->qfixuptotal );
+   rb_extrapolate( &localplayer.rb, animator->root_co, animator->root_q );
+   v3_copy( localplayer.rb.v, animator->root_v );
+}
+                        
+static void player__skate_pose( void *_animator, player_pose *pose ){
+   struct skeleton *sk = &localplayer.skeleton;
+   struct player_skate_animator *animator = _animator;
+
+   pose->type = k_player_pose_type_ik;
+   v3_copy( animator->root_co, pose->root_co );
+   v4_copy( animator->root_q, pose->root_q );
+
+   /* transform */
+   v3f ext_up,ext_co;
+   q_mulv( pose->root_q, (v3f){0.0f,1.0f,0.0f}, ext_up );
+   v3_copy( pose->root_co, ext_co );
+   v3_muladds( pose->root_co, ext_up, -0.1f, pose->root_co );
+
+   /* apply flip rotation at midpoint */
+   q_mul( animator->qflip, pose->root_q, pose->root_q );
+   q_normalize( pose->root_q );
+
+   v3f rotation_point, rco;
+   v3_muladds( ext_co, ext_up, 0.5f, rotation_point );
+   v3_sub( pose->root_co, rotation_point, rco );
+   
+   q_mulv( animator->qflip, rco, rco );
+   v3_add( rco, rotation_point, pose->root_co );
+
+   /* ANIMATIONS 
+    * ---------------------------------------------------------------------- */
+
+   mdl_keyframe apose[32], bpose[32];
+   mdl_keyframe ground_pose[32];
+   {
+      /* stand/crouch */
+      f32 dir_frame   = animator->z * (15.0f/30.0f),
+          stand_blend = animator->offset[1]*-2.0f;
+
+      pose->board.lean = animator->board_lean;
+
+      stand_blend = vg_clampf( 1.0f-animator->local_cog[1], 0, 1 );
+
+      skeleton_sample_anim( sk, player_skate.anim_stand, dir_frame, apose );
+      skeleton_sample_anim( sk, player_skate.anim_highg, dir_frame, bpose );
+      skeleton_lerp_pose( sk, apose, bpose, stand_blend, apose );
+
+      /* sliding */
+      skeleton_sample_anim( sk, player_skate.anim_slide, animator->x * 0.5f, 
+                            bpose );
+      skeleton_lerp_pose( sk, apose, bpose, animator->slide, apose );
+
+      if( animator->reverse > 0.0f ){
+         skeleton_sample_anim( sk, player_skate.anim_push, animator->push_time, 
+                               bpose );
+      }
+      else{
+         skeleton_sample_anim( sk, player_skate.anim_push_reverse, 
+                               animator->push_time, bpose );
+      }
+      skeleton_lerp_pose( sk, apose, bpose, animator->push, apose );
+
+      struct skeleton_anim *jump_anim = animator->jump_dir?
+                                        player_skate.anim_ollie:
+                                        player_skate.anim_ollie_reverse;
+
+      f32 setup_blend = vg_minf( animator->jump, 1.0f );
+      skeleton_sample_anim_clamped( sk, jump_anim, animator->jump_time, bpose );
+      skeleton_lerp_pose( sk, apose, bpose, setup_blend, ground_pose );
+   }
+   
+   mdl_keyframe air_pose[32];
+   {
+      float air_frame = (animator->airdir*0.5f+0.5f) * (15.0f/30.0f);
+      skeleton_sample_anim( sk, player_skate.anim_air, air_frame, apose );
+
+      float ang = atan2f( animator->grab[0], animator->grab[1] ),
+            ang_unit = (ang+VG_PIf) * (1.0f/VG_TAUf),
+            grab_frame = ang_unit * (15.0f/30.0f);
+
+      skeleton_sample_anim( sk, player_skate.anim_grabs, grab_frame, bpose );
+      skeleton_lerp_pose( sk, apose, bpose, animator->grabbing, air_pose );
+   }
+
+   skeleton_lerp_pose( sk, ground_pose, air_pose, animator->fly, 
+                       pose->keyframes );
+
+   mdl_keyframe *kf_board    = &pose->keyframes[localplayer.id_board-1],
+                *kf_foot_l   = &pose->keyframes[localplayer.id_ik_foot_l-1],
+                *kf_foot_r   = &pose->keyframes[localplayer.id_ik_foot_r-1],
+                *kf_knee_l   = &pose->keyframes[localplayer.id_ik_knee_l-1],
+                *kf_knee_r   = &pose->keyframes[localplayer.id_ik_knee_r-1],
+                *kf_hip      = &pose->keyframes[localplayer.id_hip-1],
+                *kf_wheels[] = { &pose->keyframes[localplayer.id_wheel_r-1],
+                                 &pose->keyframes[localplayer.id_wheel_l-1] };
+
+
+   mdl_keyframe grind_pose[32];
+   {
+      f32 frame = animator->grind_balance * 0.5f;
+
+      skeleton_sample_anim( sk, player_skate.anim_grind, frame, apose );
+      skeleton_sample_anim( sk, player_skate.anim_grind_jump, frame, bpose );
+      skeleton_lerp_pose( sk, apose, bpose, animator->jump, grind_pose );
+   }
+   skeleton_lerp_pose( sk, pose->keyframes, grind_pose, 
+                       animator->grind, pose->keyframes );
+   float add_grab_mod = 1.0f - animator->fly;
+
+   /* additive effects */
+   u32 apply_to[] = { localplayer.id_hip, 
+                      localplayer.id_ik_hand_l,
+                      localplayer.id_ik_hand_r,
+                      localplayer.id_ik_elbow_l,
+                      localplayer.id_ik_elbow_r };
+
+   float apply_rates[] = { 1.0f,
+                           0.75f,
+                           0.75f,
+                           0.75f,
+                           0.75f };
+
+   for( int i=0; i<vg_list_size(apply_to); i ++ ){
+      pose->keyframes[apply_to[i]-1].co[0] += animator->offset[0]*add_grab_mod;
+      pose->keyframes[apply_to[i]-1].co[2] += animator->offset[2]*add_grab_mod;
+   }
+
+   /* angle 'correction' */
+   v3f origin;
+   v3_add( sk->bones[localplayer.id_hip].co, kf_hip->co, origin );
+
+   for( int i=0; i<vg_list_size(apply_to); i ++ ){
+      mdl_keyframe *kf = &pose->keyframes[apply_to[i]-1];
+      keyframe_rotate_around( kf, origin, sk->bones[apply_to[i]].co,
+                              animator->qfixuptotal );
+   }
+
+   /* trick rotation */
+   v4f qtrick, qyaw, qpitch, qroll;
+   q_axis_angle( qyaw,   (v3f){0.0f,1.0f,0.0f}, animator->board_euler[0] );
+   q_axis_angle( qpitch, (v3f){1.0f,0.0f,0.0f}, animator->board_euler[1] );
+   q_axis_angle( qroll,  (v3f){0.0f,0.0f,1.0f}, animator->board_euler[2] );
+
+   q_mul( qyaw, qroll, qtrick );
+   q_mul( qpitch, qtrick, qtrick );
+   q_mul( kf_board->q, qtrick, kf_board->q );
+   q_normalize( kf_board->q );
+
+   kf_foot_l->co[2] = vg_lerpf( kf_foot_l->co[2], animator->foot_offset[0],
+                                 0.5f * animator->weight );
+   kf_foot_r->co[2] = vg_lerpf( kf_foot_r->co[2], animator->foot_offset[1],
+                                -0.5f * animator->weight );
+
+   kf_foot_l->co[1] += animator->slap;
+   kf_foot_r->co[1] += animator->slap;
+   kf_knee_l->co[1] += animator->slap;
+   kf_knee_r->co[1] += animator->slap;
+   kf_board->co[1]  += animator->slap * animator->subslap;
+   kf_hip->co[1] += animator->slap * 0.25f;
+
+   /* kickflip and shuvit are in the wrong order for some reason */
+   if( animator->trick_type == k_trick_type_kickflip ){
+      kf_foot_l->co[0] += animator->trick_foot * 0.15f;
+      kf_foot_r->co[0] -= animator->trick_foot * 0.15f;
+      kf_foot_l->co[1] -= animator->trick_foot * 0.18f;
+      kf_foot_r->co[1] -= animator->trick_foot * 0.18f;
+   }
+   else if( animator->trick_type == k_trick_type_shuvit ){
+      kf_foot_l->co[0] += animator->trick_foot * 0.2f;
+      kf_foot_l->co[1] -= animator->trick_foot * 0.18f;
+      kf_foot_r->co[0] -= animator->trick_foot * 0.1f;
+      kf_foot_r->co[1] += animator->trick_foot * 0.09f;
+   }
+   else if( animator->trick_type == k_trick_type_treflip ){
+      kf_foot_l->co[0] += animator->trick_foot * 0.2f;
+      kf_foot_r->co[0] -= animator->trick_foot * 0.15f;
+      kf_foot_l->co[1] -= animator->trick_foot * 0.18f;
+      kf_foot_r->co[1] -= animator->trick_foot * 0.18f;
+   }
+
+   /* 
+    * animation wishlist:
+    *    boardslide/grind jump animations
+    *    when tricking the slap should not appply or less apply
+    *    not animations however DONT target grinds that are vertically down.
+    */
+
+   /* truck rotation */
+   for( int i=0; i<2; i++ ){
+      float a = vg_minf( player_skate.truckv0[i][0], 1.0f );
+      a = -acosf( a ) * vg_signf( player_skate.truckv0[i][1] );
+
+      v4f q;
+      q_axis_angle( q, (v3f){0.0f,0.0f,1.0f}, a );
+      q_mul( q, kf_wheels[i]->q, kf_wheels[i]->q );
+      q_normalize( kf_wheels[i]->q );
+   }
+
+   {
+      mdl_keyframe
+         *kf_head    = &pose->keyframes[localplayer.id_head-1],
+         *kf_elbow_l = &pose->keyframes[localplayer.id_ik_elbow_l-1],
+         *kf_elbow_r = &pose->keyframes[localplayer.id_ik_elbow_r-1],
+         *kf_hand_l  = &pose->keyframes[localplayer.id_ik_hand_l-1],
+         *kf_hand_r  = &pose->keyframes[localplayer.id_ik_hand_r-1];
+
+      float warble = perlin1d( vg.time, 2.0f, 2, 300 );
+            warble *= vg_maxf(animator->grind, fabsf(animator->weight)) * 0.3f;
+
+      v4f qrot;
+      q_axis_angle( qrot, (v3f){0.8f,0.7f,0.6f}, warble );
+
+      v3f origin = {0.0f,0.2f,0.0f};
+      keyframe_rotate_around( kf_hand_l, origin, 
+                              sk->bones[localplayer.id_ik_hand_l].co, qrot );
+      keyframe_rotate_around( kf_hand_r, origin, 
+                              sk->bones[localplayer.id_ik_hand_r].co, qrot );
+      keyframe_rotate_around( kf_hip, origin, 
+                              sk->bones[localplayer.id_hip].co, qrot );
+      keyframe_rotate_around( kf_elbow_r, origin, 
+                              sk->bones[localplayer.id_ik_elbow_r].co, qrot );
+      keyframe_rotate_around( kf_elbow_l, origin, 
+                              sk->bones[localplayer.id_ik_elbow_l].co, qrot );
+
+      q_inv( qrot, qrot );
+      q_mul( qrot, kf_head->q, kf_head->q );
+      q_normalize( kf_head->q );
+   }
+}
+
+static void player__skate_effects( void *_animator, m4x3f *final_mtx,
+                                   struct player_board *board,
+                                   struct player_effects_data *effect_data ){
+
+   struct skeleton *sk = &localplayer.skeleton;
+   struct player_skate_animator *animator = _animator;
+
+   if( animator->grind > 0.5f ){
+      v3f vp0, vp1, vpc;
+      if( board ){
+         v3_copy((v3f){0.0f,0.02f, board->truck_positions[0][2]}, vp1 );
+         v3_copy((v3f){0.0f,0.02f, board->truck_positions[1][2]}, vp0 );
+      }
+      else{
+         v3_zero( vp0 );
+         v3_zero( vp1 );
+      }
+
+      v3f *board_mtx = final_mtx[ localplayer.id_board ];
+      m4x3_mulv( board_mtx, vp0, vp0 );
+      m4x3_mulv( board_mtx, vp1, vp1 );
+      v3_add( vp0, vp1, vpc );
+      v3_muls( vpc, 0.5f, vpc );
+
+      int back = 0, front = 0, mid = 0;
+
+      if( animator->activity == k_skate_activity_grind_5050 ){
+         back = 1;
+         front = 1;
+      }
+      else if( animator->activity == k_skate_activity_grind_back50 ){
+         back = 1;
+      }
+      else if( animator->activity == k_skate_activity_grind_front50 ){
+         front = 1;
+      }
+      else if( animator->activity == k_skate_activity_grind_boardslide ){
+         mid = 1;
+      }
+
+      if( back ){
+         effect_spark_apply( &effect_data->spark, vp0,
+                              animator->root_v, vg.time_delta );
+      }
+
+      if( front ){
+         effect_spark_apply( &effect_data->spark, vp1,
+                              animator->root_v, vg.time_delta );
+      }
+
+      if( mid ){
+         effect_spark_apply( &effect_data->spark, vpc,
+                              animator->root_v, vg.time_delta );
+      }
+   }
+}
+
+static void player__skate_post_animate(void){
+   struct player_skate_state *state = &player_skate.state;
+   localplayer.cam_velocity_influence = 1.0f;
+
+   v3f head = { 0.0f, 1.8f, 0.0f };
+   m4x3_mulv( localplayer.final_mtx[ localplayer.id_head ], 
+              head, state->head_position );
+   m4x3_mulv( localplayer.rb.to_local, 
+              state->head_position, state->head_position );
+}
+
+static void player__skate_reset_animator(void){
+   struct player_skate_state *state = &player_skate.state;
+
+   memset( &player_skate.animator, 0, sizeof(player_skate.animator) );
+
+   if( state->activity <= k_skate_activity_air_to_grind ) 
+      player_skate.animator.fly = 1.0f;
+   else 
+      player_skate.animator.fly = 0.0f;
+}
+
+static void player__skate_clear_mechanics(void){
+   struct player_skate_state *state = &player_skate.state;
+   state->jump_charge    = 0.0f;
+   state->charging_jump  = 0;
+   state->jump_dir       = 0;
+   v3_zero( state->flip_axis );
+   state->flip_time      = 0.0f;
+   state->flip_rate      = 0.0f;
+   state->reverse        = 0.0f;
+   state->slip           = 0.0f;
+   state->grabbing       = 0.0f;
+   v2_zero( state->grab_mouse_delta );
+   state->slap           = 0.0f;
+   state->jump_time      = 0.0;
+   state->start_push     = 0.0;
+   state->cur_push       = 0.0;
+   state->air_start      = 0.0;
+
+   v3_zero( state->air_init_v );
+   v3_zero( state->air_init_co );
+
+   state->gravity_bias   = k_gravity;
+   v3_copy( localplayer.rb.co, state->prev_pos );
+   v4_copy( localplayer.rb.q, state->smoothed_rotation );
+   v3_zero( state->throw_v );
+   v3_zero( state->trick_vel );
+   v3_zero( state->trick_euler );
+   v3_zero( state->cog_v );
+   state->grind_cooldown = 0;
+   state->surface_cooldown = 0;
+   v3_muladds( localplayer.rb.co, localplayer.rb.to_world[1], 1.0f, state->cog );
+   v3_copy( localplayer.rb.to_world[1], state->up_dir );
+   v3_copy( localplayer.rb.to_world[1], player_skate.surface_picture );
+   v3_copy( localplayer.rb.co, state->prev_pos );
+   v3_zero( player_skate.weight_distribution );
+}
+
+#include "network_compression.h"
+
+static void player__skate_animator_exchange( bitpack_ctx *ctx, void *data ){
+   struct player_skate_animator *animator = data;
+   
+   bitpack_qv3f( ctx, 24, -1024.0f, 1024.0f, animator->root_co );
+   bitpack_qquat( ctx, animator->root_q );
+
+   bitpack_qv3f( ctx, 8, -1.0f, 1.0f, animator->offset );
+   bitpack_qv3f( ctx, 8, -1.0f, 1.0f, animator->local_cog );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->slide );
+   bitpack_qf32( ctx, 8, -1.0f, 1.0f, &animator->z );
+   bitpack_qf32( ctx, 8, -1.0f, 1.0f, &animator->x );
+
+   /* these could likely be pressed down into single bits if needed */
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->fly );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->grind );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->stand );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->push );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->jump );        /*??*/
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->jump_charge ); /*??*/
+
+   /* just the sign bit? */
+   bitpack_qf32( ctx, 8, -1.0f, 1.0f, &animator->reverse );
+   bitpack_qf32( ctx, 8, -1.0f, 1.0f, &animator->delayed_slip_dir );
+   bitpack_bytes( ctx, 1, &animator->jump_dir );
+   bitpack_bytes( ctx, 1, &animator->trick_type );
+
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->grind_balance );
+   bitpack_qf32( ctx, 8, -1.0f, 1.0f, &animator->airdir );
+   bitpack_qf32( ctx, 8, -1.0f, 1.0f, &animator->weight );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->trick_foot );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->slap );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->subslap );
+   bitpack_qf32( ctx, 8,  0.0f, 1.0f, &animator->grabbing );
+
+   /* animator->wobble is ommited */
+
+   bitpack_qv2f( ctx, 8, -1.0f, 1.0f, animator->foot_offset );
+   bitpack_qquat( ctx, animator->qfixuptotal );
+   bitpack_qquat( ctx, animator->qflip );
+
+   bitpack_qv3f( ctx, 16, -100.0f, 100.0f, animator->board_euler );
+   bitpack_qf32( ctx, 8, -1.0f, 1.0f, &animator->board_lean );
+   bitpack_qv2f( ctx, 8, -1.0f, 1.0f, animator->steer );
+   bitpack_qv2f( ctx, 8, -1.0f, 1.0f, animator->grab );
+
+   bitpack_qf32( ctx, 16,  0.0f, 120.0f, &animator->push_time );
+   bitpack_qf32( ctx, 16,  0.0f, 120.0f, &animator->jump_time );
+   bitpack_qv3f( ctx, 16, -100.0f, 100.0f, animator->root_v );
+   bitpack_bytes( ctx, 1, &animator->activity );
+}
+
+static void player__skate_sfx_oneshot( u8 id, v3f pos, f32 volume ){
+   audio_lock();
+
+   if( id == k_player_skate_soundeffect_jump ){
+      audio_oneshot_3d( &audio_jumps[vg_randu32(&vg.rand)%2], 
+                        pos, 40.0f, volume );
+   }
+   else if( id == k_player_skate_soundeffect_tap ){
+      audio_oneshot_3d( &audio_taps[vg_randu32(&vg.rand)%4], 
+                        pos, 40.0f, volume );
+   }
+   else if( id == k_player_skate_soundeffect_land_good ){
+      audio_oneshot_3d( &audio_lands[vg_randu32(&vg.rand)%3], 
+                        pos, 40.0f, volume );
+   }
+   else if( id == k_player_skate_soundeffect_land_bad ){
+      audio_oneshot_3d( &audio_lands[vg_randu32(&vg.rand)%2+3], 
+                        pos, 40.0f, volume );
+   }
+   else if( id == k_player_skate_soundeffect_grind_metal ){
+      audio_oneshot_3d( &audio_board[3], pos, 40.0f, volume );
+   }
+   else if( id == k_player_skate_soundeffect_grind_wood ){
+      audio_oneshot_3d( &audio_board[8], pos, 40.0f, volume );
+   }
 
-   player__skate_clear_mechanics( player );
-   player__skate_reset_animator( player );
+   audio_unlock();
 }
 
 #endif /* PLAYER_SKATE_C */