- float new = current + diff;
-
- if( new * current < 0.0f )
- return 0.0f;
-
- return new;
-}
-
-static void player_physics_ground(void)
-{
- /*
- * Getting surface collision points,
- * the contact manifold is a triangle for simplicity.
- */
- v3f contact_front, contact_back, contact_norm, vup, vside,
- axis;
-
- float klength = 0.65f;
- m4x3_mulv( player.to_world, (v3f){ 0.15f,0.0f,-klength}, contact_norm );
- m4x3_mulv( player.to_world, (v3f){-0.15f,0.0f,-klength}, contact_front );
- m4x3_mulv( player.to_world, (v3f){ 0.00f,0.0f, klength}, contact_back );
- m3x3_mulv( player.to_world, (v3f){ 0.0f, 1.0f, 0.0f}, vup );
- m3x3_mulv( player.to_world, (v3f){ 1.0f, 0.0f, 0.0f}, vside );
-
- v3f cn0, cn1, cn2;
-
- int contact_count =
- sample_if_resistant( contact_front ) +
- sample_if_resistant( contact_back ) +
- sample_if_resistant( contact_norm );
-
- if( contact_count < 3 )
- {
- player_start_air();
- return;
- }
-
- v3f norm;
- v3f v0, v1;
- v3_sub( contact_norm, contact_front, v0 );
- v3_sub( contact_back, contact_front, v1 );
- v3_cross( v1, v0, norm );
- v3_normalize( norm );
-
- vg_line( contact_norm, contact_front, 0xff00ff00 );
- vg_line( contact_back, contact_front, 0xff0000ff );
-
- /* Surface alignment */
- float angle = v3_dot( vup, norm );
- v3_cross( vup, norm, axis );
-
- if( angle < 0.999f )
- {
- v4f correction;
- q_axis_angle( correction, axis, acosf(angle) );
- q_mul( correction, player.rot, player.rot );
- }
-
- float resistance = v3_dot( norm, player.v );
- if( resistance >= 0.0f )
- {
- player_start_air();
- return;
- }
- else
- {
- v3_muladds( player.v, norm, -resistance, player.v );
- }
-
- /* This is where velocity integration used to be */
-
- float slip = 0.0f;
-
- player.co[1] = (contact_front[1]+contact_back[1])*0.5f;
-
- v3f vel;
- m3x3_mulv( player.to_local, player.v, vel );
-
- /* Calculate local forces */
-
- slip = fabsf(-vel[0] / vel[2]) * vg_signf(vel[0]);
- if( fabsf( slip ) > 1.2f )
- slip = vg_signf( slip ) * 1.2f;
- player.slip = slip;
- player.reverse = -vg_signf(vel[2]);
-
- float substep = ktimestep * 0.2f;
- float fwd_resistance = (vg_get_button( "break" )? 5.0f: 0.02f) * -substep;
-
- for( int i=0; i<5; i++ )
- {
- vel[2] = stable_force( vel[2], vg_signf( vel[2] ) * fwd_resistance );
- vel[0] = stable_force( vel[0], vg_signf( vel[0] ) * -7.0f *substep );
- }
-
- static double start_push = 0.0;
- if( vg_get_button_down( "push" ) )
- start_push = vg_time;
-
- if( !vg_get_button("break") && vg_get_button( "push" ) )
- {
- float const k_maxpush = 16.0f,
- k_pushaccel = 5.0f;
-
- float cycle_time = vg_time-start_push,
- amt = k_pushaccel * (sinf( cycle_time * 8.0f )*0.5f+0.5f)*ktimestep,
- current = v3_length( vel ),
- new_vel = vg_minf( current + amt, k_maxpush );
- new_vel -= vg_minf(current, k_maxpush);
- vel[2] -= new_vel * player.reverse;
- }
-
- m3x3_mulv( player.to_world, vel, player.v );
-
- if( vg_get_button( "yawl" ) )
- player.iY += 3.6f * ktimestep;
- if( vg_get_button( "yawr" ) )
- player.iY -= 3.6f * ktimestep;
-
- float steer = vg_get_axis( "horizontal" );
- player.iY -= vg_signf(steer)*powf(steer,2.0f) * 1.5f * ktimestep;
-
- /* Too much lean and it starts to look like a snowboard here */
- v2_lerp( player.board_xy, (v2f){ slip*0.25f, 0.0f },
- ktimestep*5.0f, player.board_xy);
-}
-
-static void draw_cross(v3f pos,u32 colour)
-{
- v3f p0, p1;
- v3_add( (v3f){ 1.0f,0.0f,0.0f}, pos, p0 );
- v3_add( (v3f){-1.0f,0.0f,0.0f}, pos, p1 );
- vg_line( p0, p1, colour );
- v3_add( (v3f){0.0f, 1.0f,0.0f}, pos, p0 );
- v3_add( (v3f){0.0f,-1.0f,0.0f}, pos, p1 );
- vg_line( p0, p1, colour );
- v3_add( (v3f){0.0f,0.0f, 1.0f}, pos, p0 );
- v3_add( (v3f){0.0f,0.0f,-1.0f}, pos, p1 );
- vg_line( p0, p1, colour );
-}
-
-static void player_physics_air(void)
-{
- /* Debug prediciton */
-
- m3x3_mulv( player.vr, player.v, player.v );
- for( int i=0; i<player.land_log_count; i++ )
- draw_cross( player.land_target_log[i],
- player.land_target_colours[i] );
-
- draw_cross( player.land_target, 0xff0000ff );
-
- v3f ground_pos;
- v3_copy( player.co, ground_pos );
-
- ray_hit hit;
- if( bvh_scene_sample( &world.geo, ground_pos, &hit ) )
- {
- if( ground_pos[1] > player.co[1] )
- {
- player.in_air = 0;
-
- if( !ray_hit_is_ramp( &hit ) )
- {
- player.is_dead = 1;
- m4x3_mulv( player.to_world, player.view, player.follow );
- character_ragdoll_copypose( &player.mdl, player.v );
- }
-
- return;
- }
- }
-
- /* Prediction
- *
- * TODO: Find best landing surface and guide player towords it
- */
- float pstep = ktimestep*10.0f;
-
- v3f pco, pco1, pv;
- v3_copy( player.co, pco );
- v3_copy( player.v, pv );
-
- float time_to_impact = 0.0f;
- float limiter = 1.0f;
-
- for( int i=0; i<50; i++ )
- {
- v3_copy( pco, pco1 );
- apply_gravity( pv, pstep );
- v3_muladds( pco, pv, pstep, pco );
-
- //vg_line( pco, pco1, i&0x1?0xff000000:0xffffffff );
-
- ray_hit contact;
- v3f vdir;
-
- v3_sub( pco, pco1, vdir );
- contact.dist = v3_length( vdir );
- v3_divs( vdir, contact.dist, vdir);
-
- float orig_dist = contact.dist;
- if( bvh_raycast( &world.geo, pco1, vdir, &contact ))
- {
- v3f localup;
- m3x3_mulv( player.to_world, (v3f){0.0f,1.0f,0.0f}, localup );
-
- float angle = v3_dot( localup, contact.normal );
- v3f axis;
- v3_cross( localup, contact.normal, axis );
-
- time_to_impact += (contact.dist/orig_dist)*pstep;
- limiter = vg_minf( 5.0f, time_to_impact )/5.0f;
- limiter = 1.0f-limiter;
- limiter *= limiter;
- limiter = 1.0f-limiter;
-
- if( angle < 0.99f )
- {
- v4f correction;
- q_axis_angle( correction, axis, acosf(angle)*0.05f*(1.0f-limiter) );
- q_mul( correction, player.rot, player.rot );
- }
-
- draw_cross( contact.pos, 0xffff0000 );
- break;
- }
- time_to_impact += pstep;
- }
-
-
- player.iY -= vg_get_axis( "horizontal" ) * 3.6f * ktimestep;
- {
-
- float iX = vg_get_axis( "vertical" ) * 3.6f * limiter * ktimestep;
- static float siX = 0.0f;
- siX = vg_lerpf( siX, iX, 0.3f );
-
- v4f rotate;
- v3f vside;
-
- m3x3_mulv( player.to_world, (v3f){1.0f,0.0f,0.0f}, vside );
-
- q_axis_angle( rotate, vside, siX );
- q_mul( rotate, player.rot, player.rot );
- }
-
- v2f target = {0.0f,0.0f};
- v2_muladds( target, (v2f){ vg_get_axis("h1"), vg_get_axis("v1") },
- player.grab, target );
- v2_lerp( player.board_xy, target, ktimestep*3.0f, player.board_xy );