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
  60    /* Fixed items
  61     * -------------------------------------------------------
  62     */
  63
  64    void *heap;
  65    enum world_status{
  66       k_world_status_unloaded = 0,
  67       k_world_status_loading = 1,
  68       k_world_status_loaded = 2,
  69       k_world_status_unloading = 3  /* dont spawn sounds and stuff */
  70    }
  71    status;
  72
  73    struct{
  74       boxf depthbounds;
  75       int depth_computed;
  76
  77       float height;
  78       int enabled;
  79       v4f plane;
  80    }
  81    water;
  82
  83    f64 time;
  84
  85    /* STD140 */
  86    struct ub_world_lighting{
  87       v4f g_cube_min,
  88           g_cube_inv_range;
  89
  90       v4f g_water_plane,
  91           g_depth_bounds;
  92
  93       v4f g_daysky_colour;
  94       v4f g_nightsky_colour;
  95       v4f g_sunset_colour;
  96       v4f g_ambient_colour;
  97       v4f g_sunset_ambient;
  98       v4f g_sun_colour;
  99       v4f g_sun_dir;
 100       v4f g_board_0;
 101       v4f g_board_1;
 102
 103       float g_water_fog;
 104       float g_time;
 105       float g_realtime;
 106       float g_shadow_length;
 107       float g_shadow_spread;
 108
 109       float g_time_of_day;
 110       float g_day_phase;
 111       float g_sunset_phase;
 112
 113       int g_light_preview;
 114       int g_shadow_samples;
 115
 116       int g_debug_indices;
 117       int g_debug_complexity;
 118    }
 119    ub_lighting;
 120    GLuint ubo_lighting;
 121    int    ubo_bind_point;
 122
 123    GLuint tbo_light_entities,
 124           tex_light_entities,
 125           tex_light_cubes;
 126
 127    float probabilities[3];
 128
 129    v3i light_cubes;
 130    struct framebuffer heightmap;
 131
 132    /*
 133     * Dynamically allocated when world_load is called.
 134     *
 135     *                  the following arrays index somewhere into this linear
 136     *                  allocator
 137     *
 138     * (world_gen.h)
 139     * --------------------------------------------------------------------------
 140     */
 141
 142    /*
 143     * Main world .mdl
 144     */
 145    mdl_context meta;
 146
 147    GLuint *textures;
 148    u32 texture_count;
 149
 150    struct world_surface{
 151       mdl_material info;
 152       mdl_submesh sm_geo,
 153                   sm_no_collide;
 154    }
 155    * surfaces;
 156    u32 surface_count;
 157
 158    ent_worldinfo info;
 159    mdl_array_ptr ent_spawn,
 160                  ent_gate,
 161                  ent_light,
 162                  ent_route_node,
 163                  ent_path_index,
 164                  ent_checkpoint,
 165                  ent_route,
 166                  ent_water,
 167
 168                  ent_audio_clip,
 169                  ent_audio,
 170                  ent_volume,
 171                  ent_traffic,
 172                  ent_skateshop,
 173                  ent_marker,
 174                  ent_camera,
 175                  ent_swspreview;
 176
 177    ent_gate *rendering_gate;
 178
 179    /* logic
 180     * ----------------------------------------------------
 181     */
 182
 183    /* world geometry */
 184    scene_context scene_geo,
 185                  scene_no_collide,
 186                  scene_lines;
 187
 188    /* spacial mappings */
 189    bh_tree *audio_bh,
 190            *volume_bh,
 191            *geo_bh;
 192
 193    /* graphics */
 194    glmesh mesh_route_lines;
 195    glmesh mesh_geo,
 196           mesh_no_collide,
 197           mesh_water;
 198
 199    rb_object rb_geo;
 200 };
 201
 202 struct world_global{
 203    /*
 204     * Allocated as system memory
 205     * --------------------------------------------------------------------------
 206     */
 207    void *heap;
 208    char *load_target;
 209
 210    /* rendering */
 211    glmesh skydome;
 212    glmesh mesh_gate;
 213    mdl_submesh sm_gate_surface,
 214                sm_gate_marker[4];
 215
 216    double sky_time, sky_rate, sky_target_rate;
 217
 218    u32 current_run_version;
 219    double time, rewind_from, rewind_to, last_use;
 220
 221    /* water rendering */
 222    struct{
 223       struct framebuffer fbreflect, fbdepth;
 224    }
 225    water;
 226
 227    /* split flap display */
 228    struct{
 229       glmesh mesh_base, mesh_display;
 230       mdl_submesh sm_base;
 231       u32 active_route_board;
 232       scene_context scene;
 233
 234       u32 w, h;
 235       float *buffer;
 236    }
 237    sfd;
 238
 239    v3f render_gate_pos;
 240    int in_volume;
 241
 242    world_instance worlds[4];
 243    u32            active_world;
 244
 245    /* text particles */
 246    font3d font;
 247
 248    struct timer_text{
 249       char text[8];
 250       m4x3f transform;
 251       ent_gate *gate;
 252       ent_route *route;
 253    }
 254    timer_texts[4];
 255    u32 timer_text_count;
 256
 257    struct text_particle{
 258       rb_object obj;
 259       m4x3f mlocal;
 260       ent_glyph *glyph;
 261       v4f colour;
 262
 263       m4x3f mdl;
 264    }
 265    text_particles[6*4];
 266    u32 text_particle_count;
 267 }
 268 static world_global;
 269 VG_STATIC void entity_call( world_instance *world, ent_call *call );
 270
 271 VG_STATIC world_instance *get_active_world( void )
 272 {
 273    return &world_global.worlds[ world_global.active_world ];
 274 }
 275
 276 /*
 277  * API
 278  */
 279
 280 VG_STATIC
 281 int ray_hit_is_ramp( world_instance *world, ray_hit *hit );
 282
 283 VG_STATIC
 284 struct world_surface *ray_hit_surface( world_instance *world, ray_hit *hit );
 285
 286 VG_STATIC
 287 void ray_world_get_tri( world_instance *world, ray_hit *hit, v3f tri[3] );
 288
 289 VG_STATIC
 290 int ray_world( world_instance *world, v3f pos, v3f dir, ray_hit *hit );
 291
 292 VG_STATIC
 293 ent_spawn *world_find_closest_spawn( world_instance *world, v3f position )
 294 {
 295    ent_spawn *rp = NULL, *r;
 296    float min_dist = INFINITY;
 297
 298    for( u32 i=0; i<mdl_arrcount(&world->ent_spawn); i++ ){
 299       r = mdl_arritm( &world->ent_spawn, i );
 300       float d = v3_dist2( r->transform.co, position );
 301
 302       if( d < min_dist ){
 303          min_dist = d;
 304          rp = r;
 305       }
 306    }
 307
 308    if( !rp ){
 309       if( mdl_arrcount(&world->ent_spawn) ){
 310          vg_warn( "Invalid distances to spawns.. defaulting to first one.\n" );
 311          return mdl_arritm( &world->ent_spawn, 0 );
 312       }
 313       else{
 314          vg_error( "There are no spawns in the level!\n" );
 315       }
 316    }
 317
 318    return rp;
 319 }
 320
 321 VG_STATIC
 322 ent_spawn *world_find_spawn_by_name( world_instance *world, const char *name )
 323 {
 324    ent_spawn *rp = NULL, *r;
 325    for( u32 i=0; i<mdl_arrcount(&world->ent_spawn); i++ ){
 326       r = mdl_arritm( &world->ent_spawn, i );
 327       if( !strcmp( mdl_pstr(&world->meta, r->pstr_name), name ) ){
 328          rp = r;
 329          break;
 330       }
 331    }
 332
 333    if( !rp )
 334       vg_warn( "No spawn named '%s'\n", name );
 335
 336    return rp;
 337 }
 338
 339 /*
 340  * Submodules
 341  */
 342
 343 VG_STATIC float
 344    k_day_length            = 30.0f; /* minutes */
 345
 346 VG_STATIC int   k_debug_light_indices = 0,
 347                 k_debug_light_complexity = 0,
 348                 k_light_preview = 0;
 349
 350 #include "world_routes.h"
 351 #include "world_sfd.h"
 352 #include "world_render.h"
 353 #include "world_water.h"
 354 #include "world_volumes.h"
 355 #include "world_gen.h"
 356 #include "world_gate.h"
 357
 358 /*
 359  * -----------------------------------------------------------------------------
 360  *                                    Events
 361  * -----------------------------------------------------------------------------
 362  */
 363
 364 VG_STATIC int world_stop_sound( int argc, const char *argv[] )
 365 {
 366    world_instance *world = get_active_world();
 367    return 0;
 368 }
 369
 370 VG_STATIC void world_init(void)
 371 {
 372    VG_VAR_F32( k_day_length );
 373    VG_VAR_I32( k_debug_light_indices );
 374    VG_VAR_I32( k_debug_light_complexity );
 375    VG_VAR_I32( k_light_preview );
 376
 377    world_global.sky_rate = 1.0;
 378    world_global.sky_target_rate = 1.0;
 379
 380    shader_scene_standard_register();
 381    shader_scene_standard_alphatest_register();
 382    shader_scene_vertex_blend_register();
 383    shader_scene_terrain_register();
 384    shader_scene_depth_register();
 385    shader_scene_position_register();
 386
 387    shader_model_sky_register();
 388
 389    vg_info( "Loading world resources\n" );
 390
 391    vg_linear_clear( vg_mem.scratch );
 392
 393    mdl_context msky;
 394    mdl_open( &msky, "models/rs_skydome.mdl", vg_mem.scratch );
 395    mdl_load_metadata_block( &msky, vg_mem.scratch );
 396    mdl_async_load_glmesh( &msky, &world_global.skydome );
 397    mdl_close( &msky );
 398
 399    /* Other systems */
 400    vg_info( "Loading other world systems\n" );
 401
 402    vg_loader_step( world_render_init, NULL );
 403    vg_loader_step( world_sfd_init, NULL );
 404    vg_loader_step( world_water_init, NULL );
 405    vg_loader_step( world_gates_init, NULL );
 406    vg_loader_step( world_routes_init, NULL );
 407
 408    /* Allocate dynamic world memory arena */
 409    u32 max_size = 76*1024*1024;
 410    world_global.heap = vg_create_linear_allocator( vg_mem.rtmemory, max_size,
 411                                                    VG_MEMORY_SYSTEM );
 412 }
 413
 414 VG_STATIC void ent_volume_call( world_instance *world, ent_call *call )
 415 {
 416    u32 index = mdl_entity_id_id( call->id );
 417    ent_volume *volume = mdl_arritm( &world->ent_volume, index );
 418    if( !volume->target ) return;
 419
 420    if( call->function == k_ent_function_trigger ){
 421       call->id = volume->target;
 422
 423       if( volume->type == k_volume_subtype_particle ){
 424          float *co = alloca( sizeof(float)*3 );
 425          co[0] = vg_randf64()*2.0f-1.0f;
 426          co[1] = vg_randf64()*2.0f-1.0f;
 427          co[2] = vg_randf64()*2.0f-1.0f;
 428          m4x3_mulv( volume->to_world, co, co );
 429
 430          call->function = k_ent_function_particle_spawn;
 431          call->data = co;
 432          entity_call( world, call );
 433       }
 434       else{
 435          entity_call( world, call );
 436       }
 437    }
 438 }
 439
 440 VG_STATIC void ent_audio_call( world_instance *world, ent_call *call )
 441 {
 442    if( world->status == k_world_status_unloading ){
 443       vg_warn( "cannot modify audio while unloading world\n" );
 444       return;
 445    }
 446
 447    u8 world_id = (world - world_global.worlds) + 1;
 448    u32 index = mdl_entity_id_id( call->id );
 449    ent_audio *audio = mdl_arritm( &world->ent_audio, index );
 450
 451    v3f sound_co;
 452
 453    if( call->function == k_ent_function_particle_spawn ){
 454       v3_copy( call->data, sound_co );
 455    }
 456    else if( call->function == k_ent_function_trigger ){
 457       v3_copy( audio->transform.co, sound_co );
 458    }
 459    else
 460       vg_fatal_error( "ent_audio_call (invalid function id)" );
 461
 462    float chance = vg_randf64()*100.0f,
 463          bar = 0.0f;
 464
 465    for( u32 i=0; i<audio->clip_count; i++ ){
 466       ent_audio_clip *clip = mdl_arritm( &world->ent_audio_clip,
 467                                           audio->clip_start+i );
 468
 469       float mod = world->probabilities[ audio->probability_curve ],
 470             p   = clip->probability * mod;
 471
 472       bar += p;
 473
 474       if( chance < bar ){
 475          audio_lock();
 476
 477          if( audio->behaviour == k_channel_behaviour_unlimited ){
 478             audio_oneshot_3d( &clip->clip, sound_co,
 479                               audio->transform.s[0],
 480                               audio->volume );
 481          }
 482          else if( audio->behaviour == k_channel_behaviour_discard_if_full ){
 483             audio_channel *ch =
 484                audio_get_group_idle_channel( audio->group,
 485                                              audio->max_channels );
 486
 487             if( ch ){
 488                audio_channel_init( ch, &clip->clip, audio->flags );
 489                audio_channel_group( ch, audio->group );
 490                audio_channel_world( ch, world_id );
 491                audio_channel_set_spacial( ch, sound_co, audio->transform.s[0] );
 492                audio_channel_edit_volume( ch, audio->volume, 1 );
 493                ch = audio_relinquish_channel( ch );
 494             }
 495          }
 496          else if( audio->behaviour == k_channel_behaviour_crossfade_if_full){
 497             audio_channel *ch =
 498                audio_get_group_idle_channel( audio->group,
 499                                              audio->max_channels );
 500
 501             /* group is full */
 502             if( !ch ){
 503                audio_channel *existing =
 504                   audio_get_group_first_active_channel( audio->group );
 505
 506                if( existing ){
 507                   if( existing->source == &clip->clip ){
 508                      audio_unlock();
 509                      return;
 510                   }
 511
 512                   existing->group = 0;
 513                   existing = audio_channel_fadeout(existing, audio->crossfade);
 514                }
 515
 516                ch = audio_get_first_idle_channel();
 517             }
 518
 519             if( ch ){
 520                audio_channel_init( ch, &clip->clip, audio->flags );
 521                audio_channel_group( ch, audio->group );
 522                audio_channel_world( ch, world_id );
 523                audio_channel_fadein( ch, audio->crossfade );
 524                ch = audio_relinquish_channel( ch );
 525             }
 526          }
 527
 528          audio_unlock();
 529          return;
 530       }
 531    }
 532 }
 533
 534 /* finds any active playing in world and fades them out, we can only do this
 535  * while unloading */
 536 VG_STATIC void world_fadeout_audio( world_instance *world )
 537 {
 538    if( world->status != k_world_status_unloading ){
 539       vg_fatal_error( "World status must be set to 'unloading', to fadeout"
 540                       " audio.\n" );
 541    }
 542
 543    u8 world_id = (world - world_global.worlds) + 1;
 544
 545    audio_lock();
 546    for( u32 i=0; i<AUDIO_CHANNELS; i++ ){
 547       audio_channel *ch = &vg_audio.channels[i];
 548
 549       if( ch->allocated && (ch->world_id == world_id) ){
 550          ch = audio_channel_fadeout( ch, 1.0f );
 551       }
 552    }
 553    audio_unlock();
 554 }
 555
 556 VG_STATIC void world_update( world_instance *world, v3f pos )
 557 {
 558    world_global.sky_time += world_global.sky_rate * vg.time_delta;
 559    world_global.sky_rate = vg_lerp( world_global.sky_rate,
 560                                     world_global.sky_target_rate,
 561                                     vg.time_delta * 5.0 );
 562
 563    world_routes_update_timer_texts( world );
 564    world_routes_update( world );
 565    //world_routes_debug( world );
 566
 567    /* ---- traffic -------- */
 568
 569    for( u32 i=0; i<mdl_arrcount( &world->ent_traffic ); i++ ){
 570       ent_traffic *traffic = mdl_arritm( &world->ent_traffic, i );
 571
 572       u32 i1 = traffic->index,
 573           i0,
 574           i2 = i1+1;
 575
 576       if( i1 == 0 ) i0 = traffic->node_count-1;
 577       else i0 = i1-1;
 578
 579       if( i2 >= traffic->node_count ) i2 = 0;
 580
 581       i0 += traffic->start_node;
 582       i1 += traffic->start_node;
 583       i2 += traffic->start_node;
 584
 585       v3f h[3];
 586
 587       ent_route_node *rn0 = mdl_arritm( &world->ent_route_node, i0 ),
 588                      *rn1 = mdl_arritm( &world->ent_route_node, i1 ),
 589                      *rn2 = mdl_arritm( &world->ent_route_node, i2 );
 590
 591       v3_copy( rn1->co, h[1] );
 592       v3_lerp( rn0->co, rn1->co, 0.5f, h[0] );
 593       v3_lerp( rn1->co, rn2->co, 0.5f, h[2] );
 594
 595       float const k_sample_dist = 0.0025f;
 596       v3f pc, pd;
 597       eval_bezier3( h[0], h[1], h[2], traffic->t, pc );
 598       eval_bezier3( h[0], h[1], h[2], traffic->t+k_sample_dist, pd );
 599
 600       v3f v0;
 601       v3_sub( pd, pc, v0 );
 602       float length = vg_maxf( 0.0001f, v3_length( v0 ) );
 603       v3_muls( v0, 1.0f/length, v0 );
 604
 605       float mod = k_sample_dist / length;
 606
 607       traffic->t += traffic->speed * vg.time_delta * mod;
 608
 609       if( traffic->t > 1.0f ){
 610          traffic->t -= 1.0f;
 611
 612          if( traffic->t > 1.0f ) traffic->t = 0.0f;
 613
 614          traffic->index ++;
 615
 616          if( traffic->index >= traffic->node_count )
 617             traffic->index = 0;
 618       }
 619
 620       v3_copy( pc, traffic->transform.co );
 621
 622       float a = atan2f( -v0[0], v0[2] );
 623       q_axis_angle( traffic->transform.q, (v3f){0.0f,1.0f,0.0f}, -a );
 624
 625       vg_line_pt3( traffic->transform.co, 0.3f, VG__BLUE );
 626    }
 627
 628    /* ---- SFD ------------ */
 629
 630    if( mdl_arrcount( &world->ent_route ) ){
 631       u32 closest = 0;
 632       float min_dist = INFINITY;
 633
 634       for( u32 i=0; i<mdl_arrcount( &world->ent_route ); i++ ){
 635          ent_route *route = mdl_arritm( &world->ent_route, i );
 636          float dist = v3_dist2( route->board_transform[3], pos );
 637
 638          if( dist < min_dist ){
 639             min_dist = dist;
 640             closest = i;
 641          }
 642       }
 643
 644       if( (world_global.sfd.active_route_board != closest)
 645           || network_scores_updated )
 646       {
 647          network_scores_updated = 0;
 648          world_global.sfd.active_route_board = closest;
 649
 650          ent_route *route = mdl_arritm( &world->ent_route, closest );
 651          u32 id = route->official_track_id;
 652
 653          if( id != 0xffffffff ){
 654             struct netmsg_board *local_board =
 655                &scoreboard_client_data.boards[id];
 656
 657             for( int i=0; i<13; i++ ){
 658                sfd_encode( i, &local_board->data[27*i] );
 659             }
 660          }else{
 661             sfd_encode( 0, mdl_pstr( &world->meta, route->pstr_name ) );
 662             sfd_encode( 1, "No data" );
 663          }
 664       }
 665    }
 666    sfd_update();
 667
 668    static float random_accum = 0.0f;
 669    random_accum += vg.time_delta;
 670
 671    u32 random_ticks = 0;
 672
 673    while( random_accum > 0.1f ){
 674       random_accum -= 0.1f;
 675       random_ticks ++;
 676    }
 677
 678    float radius = 25.0f;
 679    boxf volume_proximity;
 680    v3_add( pos, (v3f){ radius, radius, radius }, volume_proximity[1] );
 681    v3_sub( pos, (v3f){ radius, radius, radius }, volume_proximity[0] );
 682
 683    bh_iter it;
 684    bh_iter_init_box( 0, &it, volume_proximity );
 685    i32 idx;
 686
 687    int in_volume = 0;
 688
 689    while( bh_next( world->volume_bh, &it, &idx ) ){
 690       ent_volume *volume = mdl_arritm( &world->ent_volume, idx );
 691
 692       boxf cube = {{-1.0f,-1.0f,-1.0f},{1.0f,1.0f,1.0f}};
 693
 694       if( volume->type == k_volume_subtype_trigger ){
 695          v3f local;
 696          m4x3_mulv( volume->to_local, pos, local );
 697
 698          if( (fabsf(local[0]) <= 1.0f) &&
 699              (fabsf(local[1]) <= 1.0f) &&
 700              (fabsf(local[2]) <= 1.0f) )
 701          {
 702             in_volume = 1;
 703             vg_line_boxf_transformed( volume->to_world, cube, 0xff00ff00 );
 704
 705             if( !world_global.in_volume ){
 706                ent_call basecall;
 707                basecall.function = k_ent_function_trigger;
 708                basecall.id = mdl_entity_id( k_ent_volume, idx );
 709                basecall.data = NULL;
 710
 711                entity_call( world, &basecall );
 712             }
 713          }
 714          else
 715             vg_line_boxf_transformed( volume->to_world, cube, 0xff0000ff );
 716       }
 717       else if( volume->type == k_volume_subtype_particle ){
 718          vg_line_boxf_transformed( volume->to_world, cube, 0xff00c0ff );
 719
 720          for( int j=0; j<random_ticks; j++ ){
 721             ent_call basecall;
 722             basecall.id = mdl_entity_id( k_ent_volume, idx );
 723             basecall.data = NULL;
 724
 725             entity_call( world, &basecall );
 726          }
 727       }
 728    }
 729    world_global.in_volume = in_volume;
 730
 731 #if 0
 732    if( k_debug_light_indices )
 733    {
 734       for( int i=0; i<world->light_count; i++ ){
 735          struct world_light *light = &world->lights[i];
 736          struct classtype_world_light *inf = light->inf;
 737
 738          u32 colour = 0xff000000;
 739          u8 r = inf->colour[0] * 255.0f,
 740             g = inf->colour[1] * 255.0f,
 741             b = inf->colour[2] * 255.0f;
 742
 743          colour |= r;
 744          colour |= g << 8;
 745          colour |= b << 16;
 746
 747          vg_line_pt3( light->node->co, 0.25f, colour );
 748       }
 749    }
 750
 751 #endif
 752 }
 753
 754 /*
 755  * -----------------------------------------------------------------------------
 756  *                              API implementation
 757  * -----------------------------------------------------------------------------
 758  */
 759
 760 VG_STATIC void ray_world_get_tri( world_instance *world,
 761                                   ray_hit *hit, v3f tri[3] )
 762 {
 763    for( int i=0; i<3; i++ )
 764       v3_copy( world->scene_geo.arrvertices[ hit->tri[i] ].co, tri[i] );
 765 }
 766
 767 VG_STATIC int ray_world( world_instance *world,
 768                          v3f pos, v3f dir, ray_hit *hit )
 769 {
 770    return scene_raycast( &world->scene_geo, world->geo_bh, pos, dir, hit );
 771 }
 772
 773 /*
 774  * Cast a sphere from a to b and see what time it hits
 775  */
 776 VG_STATIC int spherecast_world( world_instance *world,
 777                                 v3f pa, v3f pb, float r, float *t, v3f n )
 778 {
 779    boxf region;
 780    box_init_inf( region );
 781    box_addpt( region, pa );
 782    box_addpt( region, pb );
 783
 784    v3_add( (v3f){ r, r, r}, region[1], region[1] );
 785    v3_add( (v3f){-r,-r,-r}, region[0], region[0] );
 786
 787    v3f dir;
 788    v3_sub( pb, pa, dir );
 789
 790    v3f dir_inv;
 791    dir_inv[0] = 1.0f/dir[0];
 792    dir_inv[1] = 1.0f/dir[1];
 793    dir_inv[2] = 1.0f/dir[2];
 794
 795    int hit = -1;
 796    float min_t = 1.0f;
 797
 798    bh_iter it;
 799    bh_iter_init_box( 0, &it, region );
 800    i32 idx;
 801    while( bh_next( world->geo_bh, &it, &idx ) ){
 802       u32 *ptri = &world->scene_geo.arrindices[ idx*3 ];
 803       v3f tri[3];
 804
 805       boxf box;
 806       box_init_inf( box );
 807
 808       for( int j=0; j<3; j++ ){
 809          v3_copy( world->scene_geo.arrvertices[ptri[j]].co, tri[j] );
 810          box_addpt( box, tri[j] );
 811       }
 812
 813       v3_add( (v3f){ r, r, r}, box[1], box[1] );
 814       v3_add( (v3f){-r,-r,-r}, box[0], box[0] );
 815
 816       if( !ray_aabb1( box, pa, dir_inv, 1.0f ) )
 817          continue;
 818
 819       float t;
 820       v3f n1;
 821       if( spherecast_triangle( tri, pa, dir, r, &t, n1 ) ){
 822          if( t < min_t ){
 823             min_t = t;
 824             hit = idx;
 825             v3_copy( n1, n );
 826          }
 827       }
 828    }
 829
 830    *t = min_t;
 831    return hit;
 832 }
 833
 834 VG_STATIC
 835 struct world_surface *world_tri_index_surface( world_instance *world,
 836                                                  u32 index )
 837 {
 838    for( int i=1; i<world->surface_count; i++ ){
 839       struct world_surface *surf = &world->surfaces[i];
 840
 841       if( (index >= surf->sm_geo.vertex_start) &&
 842           (index  < surf->sm_geo.vertex_start+surf->sm_geo.vertex_count ) )
 843       {
 844          return surf;
 845       }
 846    }
 847
 848    return &world->surfaces[0];
 849 }
 850
 851 VG_STATIC struct world_surface *world_contact_surface( world_instance *world,
 852                                                          rb_ct *ct )
 853 {
 854    return world_tri_index_surface( world, ct->element_id );
 855 }
 856
 857 VG_STATIC struct world_surface *ray_hit_surface( world_instance *world,
 858                                                  ray_hit *hit )
 859 {
 860    return world_tri_index_surface( world, hit->tri[0] );
 861 }
 862
 863 /*
 864  * -----------------------------------------------------------------------------
 865  *                              Audio sampling
 866  * -----------------------------------------------------------------------------
 867  */
 868
 869 VG_STATIC
 870 enum audio_sprite_type world_audio_sample_sprite_kandom(v3f origin, v3f output);
 871 VG_STATIC void world_audio_sample_distances( v3f co, int *index, float *value );
 872
 873 #include "audio.h"
 874
 875 /*
 876  * Trace out a random point, near the player to try and determine water areas
 877  */
 878 VG_STATIC
 879 enum audio_sprite_type world_audio_sample_sprite_random(v3f origin, v3f output)
 880 {
 881    v3f chance = { (vg_randf64()-0.5f) * 30.0f,
 882                   8.0f,
 883                   (vg_randf64()-0.5f) * 30.0f };
 884
 885    v3f pos;
 886    v3_add( chance, origin, pos );
 887
 888    ray_hit contact;
 889    contact.dist = vg_minf( 16.0f, pos[1] );
 890
 891    world_instance *world = get_active_world();
 892
 893    if( ray_world( world, pos, (v3f){0.0f,-1.0f,0.0f}, &contact ) ){
 894       struct world_surface *mat = ray_hit_surface( world, &contact );
 895
 896       if( mat->info.surface_prop == k_surface_prop_grass){
 897          v3_copy( contact.pos, output );
 898          return k_audio_sprite_type_grass;
 899       }
 900       else{
 901          return k_audio_sprite_type_none;
 902       }
 903    }
 904
 905    output[0] = pos[0];
 906    output[1] = 0.0f;
 907    output[2] = pos[2];
 908
 909    float dist = fabsf(output[1] - origin[1]);
 910
 911    if( world->water.enabled && dist<=40.0f )
 912       return k_audio_sprite_type_water;
 913    else
 914       return k_audio_sprite_type_none;
 915 }
 916
 917 VG_STATIC void world_audio_sample_distances( v3f co, int *index, float *value )
 918 {
 919    float inr3 = 0.57735027,
 920          inr2 = 0.70710678118;
 921
 922    v3f sample_directions[] = {
 923       { -1.0f,  0.0f,  0.0f },
 924       {  1.0f,  0.0f,  0.0f },
 925       {  0.0f,  0.0f,  1.0f },
 926       {  0.0f,  0.0f, -1.0f },
 927       {  0.0f,  1.0f,  0.0f },
 928       {  0.0f, -1.0f,  0.0f },
 929       { -inr3,  inr3,  inr3 },
 930       {  inr3,  inr3,  inr3 },
 931       { -inr3,  inr3, -inr3 },
 932       {  inr3,  inr3, -inr3 },
 933       { -inr2,  0.0f,  inr2 },
 934       {  inr2,  0.0f,  inr2 },
 935       { -inr2,  0.0f, -inr2 },
 936       {  inr2,  0.0f, -inr2 },
 937    };
 938
 939    static int si = 0;
 940    static float distances[16];
 941
 942    ray_hit ray;
 943    ray.dist = 5.0f;
 944
 945    v3f rc, rd, ro;
 946    v3_copy( sample_directions[ si ], rd );
 947    v3_add( co, (v3f){0.0f,1.5f,0.0f}, ro );
 948    v3_copy( ro, rc );
 949
 950    float dist = 200.0f;
 951
 952    for( int i=0; i<10; i++ ){
 953       if( ray_world( get_active_world(), rc, rd, &ray ) ){
 954          dist = (float)i*5.0f + ray.dist;
 955          break;
 956       }
 957       else{
 958          v3_muladds( rc, rd, ray.dist, rc );
 959       }
 960    }
 961
 962    distances[si] = dist;
 963
 964    if( vg_lines.draw ){
 965       for( int i=0; i<14; i++ ){
 966          if( distances[i] != 200.0f ){
 967             u32 colours[] = { VG__RED, VG__BLUE, VG__GREEN,
 968                               VG__CYAN, VG__YELOW, VG__PINK,
 969                               VG__WHITE };
 970
 971             u32 colour = colours[i%7];
 972
 973             v3f p1;
 974             v3_muladds( ro, sample_directions[i], distances[i], p1 );
 975             vg_line( ro, p1, colour );
 976             vg_line_pt3( p1, 0.1f, colour );
 977          }
 978       }
 979    }
 980
 981    *index = si;
 982    *value = dist;
 983
 984    si ++;
 985    if( si >= 14 )
 986       si = 0;
 987 }
 988
 989 #endif /* WORLD_H */