world.h

   1 /*
   2  * Copyright (C) 2021-2022 Mt.ZERO Software, Harry Godden - All Rights Reserved
   3  */
   4
   5 #include "common.h"
   6
   7 #ifndef WORLD_H
   8 #define WORLD_H
   9
  10 typedef struct world_instance world_instance;
  11
  12 #include "vg/vg_loader.h"
  13
  14 #include "network.h"
  15 #include "network_msg.h"
  16 #include "scene.h"
  17 #include "render.h"
  18 #include "rigidbody.h"
  19 #include "bvh.h"
  20 #include "model.h"
  21 #include "entity.h"
  22 #include "font.h"
  23
  24 #include "shaders/scene_standard.h"
  25 #include "shaders/scene_standard_alphatest.h"
  26 #include "shaders/scene_vertex_blend.h"
  27 #include "shaders/scene_terrain.h"
  28 #include "shaders/scene_depth.h"
  29 #include "shaders/scene_position.h"
  30
  31 #include "shaders/model_sky.h"
  32
  33 enum { k_max_ui_segments = 8 };
  34
  35 enum { k_max_ui_elements = k_max_ui_segments };
  36 enum { k_max_element_verts = 10 };
  37 enum { k_max_element_indices = 20 };
  38
  39 enum { k_route_ui_max_verts = k_max_ui_elements*k_max_element_verts };
  40 enum { k_route_ui_max_indices = k_max_ui_elements*k_max_element_indices };
  41
  42 enum logic_type
  43 {
  44    k_logic_type_relay         = 1,
  45    k_logic_type_chance        = 2,
  46    k_logic_type_achievement   = 3
  47 };
  48
  49 enum geo_type
  50 {
  51    k_geo_type_solid = 0,
  52    k_geo_type_nonsolid = 1,
  53    k_geo_type_water = 2
  54 };
  55
  56 static const float k_light_cube_size = 8.0f;
  57
  58 struct world_instance {
  59    /* Fixed items
  60     * -------------------------------------------------------
  61     */
  62
  63    void *heap;
  64    char  world_name[ 64 ];
  65    enum world_status{
  66       k_world_status_unloaded = 0,
  67       k_world_status_loading = 1,
  68       k_world_status_loaded = 2
  69    }
  70    status;
  71
  72    struct{
  73       boxf depthbounds;
  74       int depth_computed;
  75
  76       float height;
  77       int enabled;
  78       v4f plane;
  79    }
  80    water;
  81
  82    /* STD140 */
  83    struct ub_world_lighting{
  84       v4f g_cube_min,
  85           g_cube_inv_range;
  86
  87       v4f g_water_plane,
  88           g_depth_bounds;
  89
  90       v4f g_daysky_colour;
  91       v4f g_nightsky_colour;
  92       v4f g_sunset_colour;
  93       v4f g_ambient_colour;
  94       v4f g_sunset_ambient;
  95       v4f g_sun_colour;
  96       v4f g_sun_dir;
  97       v4f g_board_0;
  98       v4f g_board_1;
  99
 100       float g_water_fog;
 101       float g_time;
 102       float g_realtime;
 103       float g_shadow_length;
 104       float g_shadow_spread;
 105
 106       float g_time_of_day;
 107       float g_day_phase;
 108       float g_sunset_phase;
 109
 110       int g_light_preview;
 111       int g_shadow_samples;
 112
 113       int g_debug_indices;
 114       int g_debug_complexity;
 115    }
 116    ub_lighting;
 117    GLuint ubo_lighting;
 118    int    ubo_bind_point;
 119
 120    GLuint tbo_light_entities,
 121           tex_light_entities,
 122           tex_light_cubes;
 123
 124    float probabilities[3];
 125
 126    v3i light_cubes;
 127
 128    struct framebuffer heightmap;
 129
 130    /*
 131     * Dynamically allocated when world_load is called.
 132     *
 133     *                  the following arrays index somewhere into this linear
 134     *                  allocator
 135     *
 136     * (world_gen.h)
 137     * --------------------------------------------------------------------------
 138     */
 139
 140    /*
 141     * Main world .mdl
 142     */
 143    mdl_context meta;
 144
 145    GLuint *textures;
 146    u32 texture_count;
 147
 148    struct world_surface{
 149       mdl_material info;
 150       mdl_submesh sm_geo,
 151                   sm_no_collide;
 152    }
 153    * surfaces;
 154    u32 surface_count;
 155
 156    mdl_array_ptr ent_spawn,
 157                  ent_gate,
 158                  ent_light,
 159                  ent_route_node,
 160                  ent_path_index,
 161                  ent_checkpoint,
 162                  ent_route,
 163                  ent_water,
 164
 165                  ent_audio_clip,
 166                  ent_audio,
 167                  ent_volume,
 168                  ent_traffic,
 169                  ent_skateshop,
 170                  ent_marker;
 171
 172    ent_gate *rendering_gate;
 173
 174    /* logic
 175     * ----------------------------------------------------
 176     */
 177
 178    /* world geometry */
 179    scene_context scene_geo,
 180                  scene_no_collide,
 181                  scene_lines;
 182
 183    /* spacial mappings */
 184    bh_tree *audio_bh,
 185            *volume_bh,
 186            *geo_bh;
 187
 188    /* graphics */
 189    glmesh mesh_route_lines;
 190    glmesh mesh_geo,
 191           mesh_no_collide,
 192           mesh_water;
 193
 194    rb_object rb_geo;
 195 };
 196
 197 struct world_global{
 198    /*
 199     * Allocated as system memory
 200     * --------------------------------------------------------------------------
 201     */
 202    void *heap;
 203
 204    /* rendering */
 205    glmesh skydome;
 206    glmesh mesh_gate;
 207    mdl_submesh sm_gate_surface,
 208                sm_gate_marker[4];
 209
 210    double sky_time, sky_rate, sky_target_rate;
 211
 212    u32 current_run_version;
 213    double time, rewind_from, rewind_to, last_use;
 214
 215    /* water rendering */
 216    struct{
 217       struct framebuffer fbreflect, fbdepth;
 218    }
 219    water;
 220
 221    /* split flap display */
 222    struct{
 223       glmesh mesh_base, mesh_display;
 224       mdl_submesh sm_base;
 225       u32 active_route_board;
 226       scene_context scene;
 227
 228       u32 w, h;
 229       float *buffer;
 230    }
 231    sfd;
 232
 233    v3f render_gate_pos;
 234    int in_volume;
 235
 236    int switching_to_new_world;
 237
 238    world_instance worlds[4];
 239    u32            world_count;
 240    u32            active_world;
 241
 242    /* text particles */
 243    font3d font;
 244
 245    struct timer_text{
 246       char text[8];
 247       m4x3f transform;
 248       ent_gate *gate;
 249       ent_route *route;
 250    }
 251    timer_texts[4];
 252    u32 timer_text_count;
 253
 254    struct text_particle{
 255       rb_object obj;
 256       m4x3f mlocal;
 257       ent_glyph *glyph;
 258       v4f colour;
 259
 260       m4x3f mdl;
 261    }
 262    text_particles[6*4];
 263    u32 text_particle_count;
 264 }
 265 static world_global;
 266
 267 VG_STATIC world_instance *get_active_world( void )
 268 {
 269    return &world_global.worlds[ world_global.active_world ];
 270 }
 271
 272 /*
 273  * API
 274  */
 275
 276 VG_STATIC
 277 int ray_hit_is_ramp( world_instance *world, ray_hit *hit );
 278
 279 VG_STATIC
 280 struct world_surface *ray_hit_surface( world_instance *world, ray_hit *hit );
 281
 282 VG_STATIC
 283 void ray_world_get_tri( world_instance *world, ray_hit *hit, v3f tri[3] );
 284
 285 VG_STATIC
 286 int ray_world( world_instance *world, v3f pos, v3f dir, ray_hit *hit );
 287
 288 VG_STATIC
 289 ent_spawn *world_find_closest_spawn( world_instance *world, v3f position )
 290 {
 291    ent_spawn *rp = NULL, *r;
 292    float min_dist = INFINITY;
 293
 294    for( u32 i=0; i<mdl_arrcount(&world->ent_spawn); i++ ){
 295       r = mdl_arritm( &world->ent_spawn, i );
 296       float d = v3_dist2( r->transform.co, position );
 297
 298       if( d < min_dist ){
 299          min_dist = d;
 300          rp = r;
 301       }
 302    }
 303
 304    if( !rp ){
 305       if( mdl_arrcount(&world->ent_spawn) ){
 306          vg_warn( "Invalid distances to spawns.. defaulting to first one.\n" );
 307          return mdl_arritm( &world->ent_spawn, 0 );
 308       }
 309       else{
 310          vg_error( "There are no spawns in the level!\n" );
 311       }
 312    }
 313
 314    return rp;
 315 }
 316
 317 VG_STATIC
 318 ent_spawn *world_find_spawn_by_name( world_instance *world, const char *name )
 319 {
 320    ent_spawn *rp = NULL, *r;
 321    for( u32 i=0; i<mdl_arrcount(&world->ent_spawn); i++ ){
 322       r = mdl_arritm( &world->ent_spawn, i );
 323       if( !strcmp( mdl_pstr(&world->meta, r->pstr_name), name ) ){
 324          rp = r;
 325          break;
 326       }
 327    }
 328
 329    if( !rp )
 330       vg_warn( "No spawn named '%s'\n", name );
 331
 332    return rp;
 333 }
 334
 335 /*
 336  * Submodules
 337  */
 338
 339 VG_STATIC float
 340    k_day_length            = 30.0f; /* minutes */
 341
 342 VG_STATIC int   k_debug_light_indices = 0,
 343                 k_debug_light_complexity = 0,
 344                 k_light_preview = 0;
 345
 346 #include "world_routes.h"
 347 #include "world_sfd.h"
 348 #include "world_render.h"
 349 #include "world_water.h"
 350 #include "world_volumes.h"
 351 #include "world_gen.h"
 352 #include "world_gate.h"
 353
 354 /*
 355  * -----------------------------------------------------------------------------
 356  *                                    Events
 357  * -----------------------------------------------------------------------------
 358  */
 359
 360 VG_STATIC int world_stop_sound( int argc, const char *argv[] )
 361 {
 362    world_instance *world = get_active_world();
 363    return 0;
 364 }
 365
 366 VG_STATIC void world_init(void)
 367 {
 368    VG_VAR_F32( k_day_length );
 369    VG_VAR_I32( k_debug_light_indices );
 370    VG_VAR_I32( k_debug_light_complexity );
 371    VG_VAR_I32( k_light_preview );
 372
 373    world_global.sky_rate = 1.0;
 374    world_global.sky_target_rate = 1.0;
 375
 376    shader_scene_standard_register();
 377    shader_scene_standard_alphatest_register();
 378    shader_scene_vertex_blend_register();
 379    shader_scene_terrain_register();
 380    shader_scene_depth_register();
 381    shader_scene_position_register();
 382
 383    shader_model_sky_register();
 384
 385    vg_info( "Loading world resources\n" );
 386
 387    vg_linear_clear( vg_mem.scratch );
 388
 389    mdl_context msky;
 390    mdl_open( &msky, "models/rs_skydome.mdl", vg_mem.scratch );
 391    mdl_load_metadata_block( &msky, vg_mem.scratch );
 392    mdl_async_load_glmesh( &msky, &world_global.skydome );
 393    mdl_close( &msky );
 394
 395    /* Other systems */
 396    vg_info( "Loading other world systems\n" );
 397
 398    vg_loader_step( world_render_init, NULL );
 399    vg_loader_step( world_sfd_init, NULL );
 400    vg_loader_step( world_water_init, NULL );
 401    vg_loader_step( world_gates_init, NULL );
 402    vg_loader_step( world_routes_init, NULL );
 403
 404    /* Allocate dynamic world memory arena */
 405    u32 max_size = 76*1024*1024;
 406    world_global.heap = vg_create_linear_allocator( vg_mem.rtmemory, max_size,
 407                                                    VG_MEMORY_SYSTEM );
 408 }
 409
 410 VG_STATIC void ent_volume_call( world_instance *world, ent_call *call )
 411 {
 412    u32 index = mdl_entity_id_id( call->id );
 413    ent_volume *volume = mdl_arritm( &world->ent_volume, index );
 414    if( !volume->target ) return;
 415
 416    if( call->function == k_ent_function_trigger ){
 417       call->id = volume->target;
 418
 419       if( volume->type == k_volume_subtype_particle ){
 420          float *co = alloca( sizeof(float)*3 );
 421          co[0] = vg_randf()*2.0f-1.0f;
 422          co[1] = vg_randf()*2.0f-1.0f;
 423          co[2] = vg_randf()*2.0f-1.0f;
 424          m4x3_mulv( volume->to_world, co, co );
 425
 426          call->function = k_ent_function_particle_spawn;
 427          call->data = co;
 428          entity_call( world, call );
 429       }
 430       else{
 431          entity_call( world, call );
 432       }
 433    }
 434 }
 435
 436 VG_STATIC void ent_audio_call( world_instance *world, ent_call *call )
 437 {
 438    u32 index = mdl_entity_id_id( call->id );
 439    ent_audio *audio = mdl_arritm( &world->ent_audio, index );
 440
 441    v3f sound_co;
 442
 443    if( call->function == k_ent_function_particle_spawn ){
 444       v3_copy( call->data, sound_co );
 445    }
 446    else if( call->function == k_ent_function_trigger ){
 447       v3_copy( audio->transform.co, sound_co );
 448    }
 449    else
 450       vg_fatal_error( "ent_audio_call (invalid function id)" );
 451
 452    float chance = vg_randf()*100.0f,
 453          bar = 0.0f;
 454
 455    for( u32 i=0; i<audio->clip_count; i++ ){
 456       ent_audio_clip *clip = mdl_arritm( &world->ent_audio_clip,
 457                                           audio->clip_start+i );
 458
 459       float mod = world->probabilities[ audio->probability_curve ],
 460             p   = clip->probability * mod;
 461
 462       bar += p;
 463
 464       if( chance < bar ){
 465
 466          audio_lock();
 467
 468          if( audio->behaviour == k_channel_behaviour_unlimited ){
 469             audio_oneshot_3d( &clip->clip, sound_co,
 470                               audio->transform.s[0],
 471                               audio->volume );
 472          }
 473          else if( audio->behaviour == k_channel_behaviour_discard_if_full ){
 474             audio_channel *ch =
 475                audio_get_group_idle_channel( audio->group,
 476                                              audio->max_channels );
 477
 478             if( ch ){
 479                audio_channel_init( ch, &clip->clip, audio->flags );
 480                audio_channel_group( ch, audio->group );
 481                audio_channel_set_spacial( ch, sound_co, audio->transform.s[0] );
 482                audio_channel_edit_volume( ch, audio->volume, 1 );
 483                ch = audio_relinquish_channel( ch );
 484             }
 485          }
 486          else if( audio->behaviour == k_channel_behaviour_crossfade_if_full){
 487             audio_channel *ch =
 488                audio_get_group_idle_channel( audio->group,
 489                                              audio->max_channels );
 490
 491             /* group is full */
 492             if( !ch ){
 493                audio_channel *existing =
 494                   audio_get_group_first_active_channel( audio->group );
 495
 496                if( existing ){
 497                   if( existing->source == &clip->clip ){
 498                      audio_unlock();
 499                      return;
 500                   }
 501
 502                   existing->group = 0;
 503                   existing = audio_channel_fadeout(existing, audio->crossfade);
 504                }
 505
 506                ch = audio_get_first_idle_channel();
 507             }
 508
 509             if( ch ){
 510                audio_channel_init( ch, &clip->clip, audio->flags );
 511                audio_channel_group( ch, audio->group );
 512                audio_channel_fadein( ch, audio->crossfade );
 513                ch = audio_relinquish_channel( ch );
 514             }
 515          }
 516
 517          audio_unlock();
 518          return;
 519       }
 520    }
 521 }
 522
 523 VG_STATIC void world_update( world_instance *world, v3f pos )
 524 {
 525    world_global.sky_time += world_global.sky_rate * vg.time_delta;
 526    world_global.sky_rate = vg_lerp( world_global.sky_rate,
 527                                     world_global.sky_target_rate,
 528                                     vg.time_delta * 5.0 );
 529
 530    world_routes_update_timer_texts( world );
 531    world_routes_update( world );
 532    //world_routes_debug( world );
 533
 534    /* ---- traffic -------- */
 535
 536    for( u32 i=0; i<mdl_arrcount( &world->ent_traffic ); i++ ){
 537       ent_traffic *traffic = mdl_arritm( &world->ent_traffic, i );
 538
 539       u32 i1 = traffic->index,
 540           i0,
 541           i2 = i1+1;
 542
 543       if( i1 == 0 ) i0 = traffic->node_count-1;
 544       else i0 = i1-1;
 545
 546       if( i2 >= traffic->node_count ) i2 = 0;
 547
 548       i0 += traffic->start_node;
 549       i1 += traffic->start_node;
 550       i2 += traffic->start_node;
 551
 552       v3f h[3];
 553
 554       ent_route_node *rn0 = mdl_arritm( &world->ent_route_node, i0 ),
 555                      *rn1 = mdl_arritm( &world->ent_route_node, i1 ),
 556                      *rn2 = mdl_arritm( &world->ent_route_node, i2 );
 557
 558       v3_copy( rn1->co, h[1] );
 559       v3_lerp( rn0->co, rn1->co, 0.5f, h[0] );
 560       v3_lerp( rn1->co, rn2->co, 0.5f, h[2] );
 561
 562       float const k_sample_dist = 0.0025f;
 563       v3f pc, pd;
 564       eval_bezier3( h[0], h[1], h[2], traffic->t, pc );
 565       eval_bezier3( h[0], h[1], h[2], traffic->t+k_sample_dist, pd );
 566
 567       v3f v0;
 568       v3_sub( pd, pc, v0 );
 569       float length = vg_maxf( 0.0001f, v3_length( v0 ) );
 570       v3_muls( v0, 1.0f/length, v0 );
 571
 572       float mod = k_sample_dist / length;
 573
 574       traffic->t += traffic->speed * vg.time_delta * mod;
 575
 576       if( traffic->t > 1.0f ){
 577          traffic->t -= 1.0f;
 578
 579          if( traffic->t > 1.0f ) traffic->t = 0.0f;
 580
 581          traffic->index ++;
 582
 583          if( traffic->index >= traffic->node_count )
 584             traffic->index = 0;
 585       }
 586
 587       v3_copy( pc, traffic->transform.co );
 588
 589       float a = atan2f( -v0[0], v0[2] );
 590       q_axis_angle( traffic->transform.q, (v3f){0.0f,1.0f,0.0f}, -a );
 591
 592       vg_line_pt3( traffic->transform.co, 0.3f, VG__BLUE );
 593    }
 594
 595    /* ---- SFD ------------ */
 596
 597    if( mdl_arrcount( &world->ent_route ) ){
 598       u32 closest = 0;
 599       float min_dist = INFINITY;
 600
 601       for( u32 i=0; i<mdl_arrcount( &world->ent_route ); i++ ){
 602          ent_route *route = mdl_arritm( &world->ent_route, i );
 603          float dist = v3_dist2( route->board_transform[3], pos );
 604
 605          if( dist < min_dist ){
 606             min_dist = dist;
 607             closest = i;
 608          }
 609       }
 610
 611       if( (world_global.sfd.active_route_board != closest)
 612           || network_scores_updated )
 613       {
 614          network_scores_updated = 0;
 615          world_global.sfd.active_route_board = closest;
 616
 617          ent_route *route = mdl_arritm( &world->ent_route, closest );
 618          u32 id = route->official_track_id;
 619
 620          if( id != 0xffffffff ){
 621             struct netmsg_board *local_board =
 622                &scoreboard_client_data.boards[id];
 623
 624             for( int i=0; i<13; i++ ){
 625                sfd_encode( i, &local_board->data[27*i] );
 626             }
 627          }else{
 628             sfd_encode( 0, mdl_pstr( &world->meta, route->pstr_name ) );
 629             sfd_encode( 1, "No data" );
 630          }
 631       }
 632    }
 633    sfd_update();
 634
 635    static float random_accum = 0.0f;
 636    random_accum += vg.time_delta;
 637
 638    u32 random_ticks = 0;
 639
 640    while( random_accum > 0.1f ){
 641       random_accum -= 0.1f;
 642       random_ticks ++;
 643    }
 644
 645    float radius = 25.0f;
 646    boxf volume_proximity;
 647    v3_add( pos, (v3f){ radius, radius, radius }, volume_proximity[1] );
 648    v3_sub( pos, (v3f){ radius, radius, radius }, volume_proximity[0] );
 649
 650    bh_iter it;
 651    bh_iter_init( 0, &it );
 652    int idx;
 653
 654    int in_volume = 0;
 655
 656    while( bh_next( world->volume_bh, &it, volume_proximity, &idx ) ){
 657       ent_volume *volume = mdl_arritm( &world->ent_volume, idx );
 658
 659       boxf cube = {{-1.0f,-1.0f,-1.0f},{1.0f,1.0f,1.0f}};
 660
 661       if( volume->type == k_volume_subtype_trigger ){
 662          v3f local;
 663          m4x3_mulv( volume->to_local, pos, local );
 664
 665          if( (fabsf(local[0]) <= 1.0f) &&
 666              (fabsf(local[1]) <= 1.0f) &&
 667              (fabsf(local[2]) <= 1.0f) )
 668          {
 669             in_volume = 1;
 670             vg_line_boxf_transformed( volume->to_world, cube, 0xff00ff00 );
 671
 672             if( !world_global.in_volume ){
 673                ent_call basecall;
 674                basecall.function = k_ent_function_trigger;
 675                basecall.id = mdl_entity_id( k_ent_volume, idx );
 676                basecall.data = NULL;
 677
 678                entity_call( world, &basecall );
 679             }
 680          }
 681          else
 682             vg_line_boxf_transformed( volume->to_world, cube, 0xff0000ff );
 683       }
 684       else if( volume->type == k_volume_subtype_particle ){
 685          vg_line_boxf_transformed( volume->to_world, cube, 0xff00c0ff );
 686
 687          for( int j=0; j<random_ticks; j++ ){
 688             ent_call basecall;
 689             basecall.id = mdl_entity_id( k_ent_volume, idx );
 690             basecall.data = NULL;
 691
 692             entity_call( world, &basecall );
 693          }
 694       }
 695    }
 696    world_global.in_volume = in_volume;
 697
 698 #if 0
 699    if( k_debug_light_indices )
 700    {
 701       for( int i=0; i<world->light_count; i++ ){
 702          struct world_light *light = &world->lights[i];
 703          struct classtype_world_light *inf = light->inf;
 704
 705          u32 colour = 0xff000000;
 706          u8 r = inf->colour[0] * 255.0f,
 707             g = inf->colour[1] * 255.0f,
 708             b = inf->colour[2] * 255.0f;
 709
 710          colour |= r;
 711          colour |= g << 8;
 712          colour |= b << 16;
 713
 714          vg_line_pt3( light->node->co, 0.25f, colour );
 715       }
 716    }
 717
 718 #endif
 719 }
 720
 721 /*
 722  * -----------------------------------------------------------------------------
 723  *                              API implementation
 724  * -----------------------------------------------------------------------------
 725  */
 726
 727 VG_STATIC void ray_world_get_tri( world_instance *world,
 728                                   ray_hit *hit, v3f tri[3] )
 729 {
 730    for( int i=0; i<3; i++ )
 731       v3_copy( world->scene_geo.arrvertices[ hit->tri[i] ].co, tri[i] );
 732 }
 733
 734 VG_STATIC int ray_world( world_instance *world,
 735                          v3f pos, v3f dir, ray_hit *hit )
 736 {
 737    return scene_raycast( &world->scene_geo, world->geo_bh, pos, dir, hit );
 738 }
 739
 740 /*
 741  * Cast a sphere from a to b and see what time it hits
 742  */
 743 VG_STATIC int spherecast_world( world_instance *world,
 744                                 v3f pa, v3f pb, float r, float *t, v3f n )
 745 {
 746    bh_iter it;
 747    bh_iter_init( 0, &it );
 748
 749    boxf region;
 750    box_init_inf( region );
 751    box_addpt( region, pa );
 752    box_addpt( region, pb );
 753
 754    v3_add( (v3f){ r, r, r}, region[1], region[1] );
 755    v3_add( (v3f){-r,-r,-r}, region[0], region[0] );
 756
 757    v3f dir;
 758    v3_sub( pb, pa, dir );
 759
 760    v3f dir_inv;
 761    dir_inv[0] = 1.0f/dir[0];
 762    dir_inv[1] = 1.0f/dir[1];
 763    dir_inv[2] = 1.0f/dir[2];
 764
 765    int hit = -1;
 766    float min_t = 1.0f;
 767
 768    int idx;
 769    while( bh_next( world->geo_bh, &it, region, &idx ) ){
 770       u32 *ptri = &world->scene_geo.arrindices[ idx*3 ];
 771       v3f tri[3];
 772
 773       boxf box;
 774       box_init_inf( box );
 775
 776       for( int j=0; j<3; j++ ){
 777          v3_copy( world->scene_geo.arrvertices[ptri[j]].co, tri[j] );
 778          box_addpt( box, tri[j] );
 779       }
 780
 781       v3_add( (v3f){ r, r, r}, box[1], box[1] );
 782       v3_add( (v3f){-r,-r,-r}, box[0], box[0] );
 783
 784       if( !ray_aabb1( box, pa, dir_inv, 1.0f ) )
 785          continue;
 786
 787       float t;
 788       v3f n1;
 789       if( spherecast_triangle( tri, pa, dir, r, &t, n1 ) ){
 790          if( t < min_t ){
 791             min_t = t;
 792             hit = idx;
 793             v3_copy( n1, n );
 794          }
 795       }
 796    }
 797
 798    *t = min_t;
 799    return hit;
 800 }
 801
 802 VG_STATIC
 803 struct world_surface *world_tri_index_surface( world_instance *world,
 804                                                  u32 index )
 805 {
 806    for( int i=1; i<world->surface_count; i++ ){
 807       struct world_surface *surf = &world->surfaces[i];
 808
 809       if( (index >= surf->sm_geo.vertex_start) &&
 810           (index  < surf->sm_geo.vertex_start+surf->sm_geo.vertex_count ) )
 811       {
 812          return surf;
 813       }
 814    }
 815
 816    return &world->surfaces[0];
 817 }
 818
 819 VG_STATIC struct world_surface *world_contact_surface( world_instance *world,
 820                                                          rb_ct *ct )
 821 {
 822    return world_tri_index_surface( world, ct->element_id );
 823 }
 824
 825 VG_STATIC struct world_surface *ray_hit_surface( world_instance *world,
 826                                                  ray_hit *hit )
 827 {
 828    return world_tri_index_surface( world, hit->tri[0] );
 829 }
 830
 831 /*
 832  * -----------------------------------------------------------------------------
 833  *                              Audio sampling
 834  * -----------------------------------------------------------------------------
 835  */
 836
 837 VG_STATIC
 838 enum audio_sprite_type world_audio_sample_sprite_random(v3f origin, v3f output);
 839 VG_STATIC void world_audio_sample_distances( v3f co, int *index, float *value );
 840
 841 #include "audio.h"
 842
 843 /*
 844  * Trace out a random point, near the player to try and determine water areas
 845  */
 846 VG_STATIC
 847 enum audio_sprite_type world_audio_sample_sprite_random(v3f origin, v3f output)
 848 {
 849    v3f chance = { (vg_randf()-0.5f) * 30.0f,
 850                   8.0f,
 851                   (vg_randf()-0.5f) * 30.0f };
 852
 853    v3f pos;
 854    v3_add( chance, origin, pos );
 855
 856    ray_hit contact;
 857    contact.dist = vg_minf( 16.0f, pos[1] );
 858
 859    world_instance *world = get_active_world();
 860
 861    if( ray_world( world, pos, (v3f){0.0f,-1.0f,0.0f}, &contact ) ){
 862       struct world_surface *mat = ray_hit_surface( world, &contact );
 863
 864       if( mat->info.surface_prop == k_surface_prop_grass){
 865          v3_copy( contact.pos, output );
 866          return k_audio_sprite_type_grass;
 867       }
 868       else{
 869          return k_audio_sprite_type_none;
 870       }
 871    }
 872
 873    output[0] = pos[0];
 874    output[1] = 0.0f;
 875    output[2] = pos[2];
 876
 877    float dist = fabsf(output[1] - origin[1]);
 878
 879    if( world->water.enabled && dist<=40.0f )
 880       return k_audio_sprite_type_water;
 881    else
 882       return k_audio_sprite_type_none;
 883 }
 884
 885 VG_STATIC void world_audio_sample_distances( v3f co, int *index, float *value )
 886 {
 887    float inr3 = 0.57735027,
 888          inr2 = 0.70710678118;
 889
 890    v3f sample_directions[] = {
 891       { -1.0f,  0.0f,  0.0f },
 892       {  1.0f,  0.0f,  0.0f },
 893       {  0.0f,  0.0f,  1.0f },
 894       {  0.0f,  0.0f, -1.0f },
 895       {  0.0f,  1.0f,  0.0f },
 896       {  0.0f, -1.0f,  0.0f },
 897       { -inr3,  inr3,  inr3 },
 898       {  inr3,  inr3,  inr3 },
 899       { -inr3,  inr3, -inr3 },
 900       {  inr3,  inr3, -inr3 },
 901       { -inr2,  0.0f,  inr2 },
 902       {  inr2,  0.0f,  inr2 },
 903       { -inr2,  0.0f, -inr2 },
 904       {  inr2,  0.0f, -inr2 },
 905    };
 906
 907    static int si = 0;
 908    static float distances[16];
 909
 910    ray_hit ray;
 911    ray.dist = 5.0f;
 912
 913    v3f rc, rd, ro;
 914    v3_copy( sample_directions[ si ], rd );
 915    v3_add( co, (v3f){0.0f,1.5f,0.0f}, ro );
 916    v3_copy( ro, rc );
 917
 918    float dist = 200.0f;
 919
 920    for( int i=0; i<10; i++ ){
 921       if( ray_world( get_active_world(), rc, rd, &ray ) ){
 922          dist = (float)i*5.0f + ray.dist;
 923          break;
 924       }
 925       else{
 926          v3_muladds( rc, rd, ray.dist, rc );
 927       }
 928    }
 929
 930    distances[si] = dist;
 931
 932    if( vg_lines.draw ){
 933       for( int i=0; i<14; i++ ){
 934          if( distances[i] != 200.0f ){
 935             u32 colours[] = { VG__RED, VG__BLUE, VG__GREEN,
 936                               VG__CYAN, VG__YELOW, VG__PINK,
 937                               VG__WHITE };
 938
 939             u32 colour = colours[i%7];
 940
 941             v3f p1;
 942             v3_muladds( ro, sample_directions[i], distances[i], p1 );
 943             vg_line( ro, p1, colour );
 944             vg_line_pt3( p1, 0.1f, colour );
 945          }
 946       }
 947    }
 948
 949    *index = si;
 950    *value = dist;
 951
 952    si ++;
 953    if( si >= 14 )
 954       si = 0;
 955 }
 956
 957 #endif /* WORLD_H */