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
 169    ent_gate *rendering_gate;
 170
 171    /* logic
 172     * ----------------------------------------------------
 173     */
 174
 175    /* world geometry */
 176    scene *scene_geo,
 177          *scene_no_collide,
 178          *scene_lines;
 179
 180    /* spacial mappings */
 181    bh_tree *audio_bh,
 182            *volume_bh,
 183            *geo_bh;
 184
 185    /* graphics */
 186    glmesh mesh_route_lines;
 187    glmesh mesh_geo,
 188           mesh_no_collide,
 189           mesh_water;
 190
 191    rb_object rb_geo;
 192 };
 193
 194 struct world_global{
 195    /*
 196     * Allocated as system memory
 197     * --------------------------------------------------------------------------
 198     */
 199    void *heap;
 200
 201    /* rendering */
 202    glmesh skydome;
 203    glmesh mesh_gate;
 204    mdl_submesh sm_gate_surface,
 205                sm_gate_marker[4];
 206
 207    double sky_time, sky_rate, sky_target_rate;
 208
 209    u32 current_run_version;
 210    double time, rewind_from, rewind_to, last_use;
 211
 212    /* water rendering */
 213    struct{
 214       struct framebuffer fbreflect, fbdepth;
 215    }
 216    water;
 217
 218    /* split flap display */
 219    struct{
 220       glmesh mesh_base, mesh_display;
 221       mdl_submesh sm_base;
 222       u32 active_route_board;
 223
 224       u32 w, h;
 225       float *buffer;
 226    }
 227    sfd;
 228
 229    v3f render_gate_pos;
 230    int in_volume;
 231
 232    int switching_to_new_world;
 233
 234    world_instance worlds[4];
 235    u32            world_count;
 236    u32            active_world;
 237
 238    /* text particles */
 239    font3d font;
 240
 241    struct timer_text{
 242       char text[8];
 243       m4x3f transform;
 244       ent_gate *gate;
 245       ent_route *route;
 246    }
 247    timer_texts[4];
 248    u32 timer_text_count;
 249
 250    struct text_particle{
 251       rb_object obj;
 252       m4x3f mlocal;
 253       ent_glyph *glyph;
 254       v4f colour;
 255
 256       m4x3f mdl;
 257    }
 258    text_particles[6*4];
 259    u32 text_particle_count;
 260 }
 261 static world_global;
 262
 263 VG_STATIC world_instance *get_active_world( void )
 264 {
 265    return &world_global.worlds[ world_global.active_world ];
 266 }
 267
 268 /*
 269  * API
 270  */
 271
 272 VG_STATIC
 273 int ray_hit_is_ramp( world_instance *world, ray_hit *hit );
 274
 275 VG_STATIC
 276 struct world_surface *ray_hit_surface( world_instance *world, ray_hit *hit );
 277
 278 VG_STATIC
 279 void ray_world_get_tri( world_instance *world, ray_hit *hit, v3f tri[3] );
 280
 281 VG_STATIC
 282 int ray_world( world_instance *world, v3f pos, v3f dir, ray_hit *hit );
 283
 284 VG_STATIC
 285 ent_spawn *world_find_closest_spawn( world_instance *world, v3f position )
 286 {
 287    ent_spawn *rp = NULL, *r;
 288    float min_dist = INFINITY;
 289
 290    for( u32 i=0; i<mdl_arrcount(&world->ent_spawn); i++ ){
 291       r = mdl_arritm( &world->ent_spawn, i );
 292       float d = v3_dist2( r->transform.co, position );
 293
 294       if( d < min_dist ){
 295          min_dist = d;
 296          rp = r;
 297       }
 298    }
 299
 300    if( !rp ){
 301       if( mdl_arrcount(&world->ent_spawn) ){
 302          vg_warn( "Invalid distances to spawns.. defaulting to first one.\n" );
 303          return mdl_arritm( &world->ent_spawn, 0 );
 304       }
 305       else{
 306          vg_error( "There are no spawns in the level!\n" );
 307       }
 308    }
 309
 310    return rp;
 311 }
 312
 313 VG_STATIC
 314 ent_spawn *world_find_spawn_by_name( world_instance *world, const char *name )
 315 {
 316    ent_spawn *rp = NULL, *r;
 317    for( u32 i=0; i<mdl_arrcount(&world->ent_spawn); i++ ){
 318       r = mdl_arritm( &world->ent_spawn, i );
 319       if( !strcmp( mdl_pstr(&world->meta, r->pstr_name), name ) ){
 320          rp = r;
 321          break;
 322       }
 323    }
 324
 325    if( !rp )
 326       vg_warn( "No spawn named '%s'\n", name );
 327
 328    return rp;
 329 }
 330
 331 /*
 332  * Submodules
 333  */
 334
 335 VG_STATIC float
 336    k_day_length            = 30.0f; /* minutes */
 337
 338 VG_STATIC int   k_debug_light_indices = 0,
 339                 k_debug_light_complexity = 0,
 340                 k_light_preview = 0;
 341
 342 #include "world_routes.h"
 343 #include "world_sfd.h"
 344 #include "world_render.h"
 345 #include "world_water.h"
 346 #include "world_volumes.h"
 347 #include "world_gen.h"
 348 #include "world_gate.h"
 349
 350 /*
 351  * -----------------------------------------------------------------------------
 352  *                                    Events
 353  * -----------------------------------------------------------------------------
 354  */
 355
 356 VG_STATIC int world_stop_sound( int argc, const char *argv[] )
 357 {
 358    world_instance *world = get_active_world();
 359    return 0;
 360 }
 361
 362 VG_STATIC void world_init(void)
 363 {
 364    VG_VAR_F32( k_day_length );
 365    VG_VAR_I32( k_debug_light_indices );
 366    VG_VAR_I32( k_debug_light_complexity );
 367    VG_VAR_I32( k_light_preview );
 368
 369    world_global.sky_rate = 1.0;
 370    world_global.sky_target_rate = 1.0;
 371
 372    shader_scene_standard_register();
 373    shader_scene_standard_alphatest_register();
 374    shader_scene_vertex_blend_register();
 375    shader_scene_terrain_register();
 376    shader_scene_depth_register();
 377    shader_scene_position_register();
 378
 379    shader_model_sky_register();
 380
 381    vg_info( "Loading world resources\n" );
 382
 383    vg_linear_clear( vg_mem.scratch );
 384
 385    mdl_context msky;
 386    mdl_open( &msky, "models/rs_skydome.mdl", vg_mem.scratch );
 387    mdl_load_metadata_block( &msky, vg_mem.scratch );
 388    mdl_load_mesh_block( &msky, vg_mem.scratch );
 389    mdl_close( &msky );
 390
 391    vg_acquire_thread_sync();
 392    {
 393       mdl_unpack_glmesh( &msky, &world_global.skydome );
 394    }
 395    vg_release_thread_sync();
 396
 397    /* Other systems */
 398    vg_info( "Loading other world systems\n" );
 399
 400    vg_loader_step( world_render_init, NULL );
 401    vg_loader_step( world_sfd_init, NULL );
 402    vg_loader_step( world_water_init, NULL );
 403    vg_loader_step( world_gates_init, NULL );
 404    vg_loader_step( world_routes_init, NULL );
 405
 406    /* Allocate dynamic world memory arena */
 407    u32 max_size = 76*1024*1024;
 408    world_global.heap = vg_create_linear_allocator( vg_mem.rtmemory, max_size,
 409                                                    VG_MEMORY_SYSTEM );
 410 }
 411
 412 typedef struct ent_call ent_call;
 413 struct ent_call{
 414    ent_index ent;
 415    u32 function;
 416    void *data;
 417 };
 418
 419 VG_STATIC void entity_call( world_instance *world, ent_call *call );
 420
 421 VG_STATIC void ent_volume_call( world_instance *world, ent_call *call )
 422 {
 423    ent_volume *volume = mdl_arritm( &world->ent_volume, call->ent.index );
 424    if( !volume->target.type ) return;
 425
 426    if( call->function == k_ent_function_trigger ){
 427       call->ent = volume->target;
 428
 429       if( volume->type == k_volume_subtype_particle ){
 430          float *co = alloca( sizeof(float)*3 );
 431          co[0] = vg_randf()*2.0f-1.0f;
 432          co[1] = vg_randf()*2.0f-1.0f;
 433          co[2] = vg_randf()*2.0f-1.0f;
 434          m4x3_mulv( volume->to_world, co, co );
 435
 436          call->function = k_ent_function_particle_spawn;
 437          call->data = co;
 438          entity_call( world, call );
 439       }
 440       else
 441          entity_call( world, call );
 442    }
 443 }
 444
 445 VG_STATIC void ent_audio_call( world_instance *world, ent_call *call )
 446 {
 447    ent_audio *audio = mdl_arritm( &world->ent_audio, call->ent.index );
 448
 449    v3f sound_co;
 450
 451    if( call->function == k_ent_function_particle_spawn ){
 452       v3_copy( call->data, sound_co );
 453    }
 454    else if( call->function == k_ent_function_trigger ){
 455       v3_copy( audio->transform.co, sound_co );
 456    }
 457    else
 458       vg_fatal_exit_loop( "ent_audio_call (invalid function id)" );
 459
 460    float chance = vg_randf()*100.0f,
 461          bar = 0.0f;
 462
 463    for( u32 i=0; i<audio->clip_count; i++ ){
 464       ent_audio_clip *clip = mdl_arritm( &world->ent_audio_clip,
 465                                           audio->clip_start+i );
 466
 467       float mod = world->probabilities[ audio->probability_curve ],
 468             p   = clip->probability * mod;
 469
 470       bar += p;
 471
 472       if( chance < bar ){
 473
 474          audio_lock();
 475
 476          if( audio->behaviour == k_channel_behaviour_unlimited ){
 477             audio_oneshot_3d( &clip->clip, sound_co,
 478                               audio->transform.s[0],
 479                               audio->volume );
 480          }
 481          else if( audio->behaviour == k_channel_behaviour_discard_if_full ){
 482             audio_channel *ch =
 483                audio_get_group_idle_channel( audio->group,
 484                                              audio->max_channels );
 485
 486             if( ch ){
 487                audio_channel_init( ch, &clip->clip, audio->flags );
 488                audio_channel_group( ch, audio->group );
 489                audio_channel_set_spacial( ch, sound_co, audio->transform.s[0] );
 490                audio_channel_edit_volume( ch, audio->volume, 1 );
 491                ch = audio_relinquish_channel( ch );
 492             }
 493          }
 494          else if( audio->behaviour == k_channel_behaviour_crossfade_if_full){
 495             audio_channel *ch =
 496                audio_get_group_idle_channel( audio->group,
 497                                              audio->max_channels );
 498
 499             /* group is full */
 500             if( !ch ){
 501                audio_channel *existing =
 502                   audio_get_group_first_active_channel( audio->group );
 503
 504                if( existing ){
 505                   if( existing->source == &clip->clip ){
 506                      audio_unlock();
 507                      return;
 508                   }
 509
 510                   existing->group = 0;
 511                   existing = audio_channel_fadeout(existing, audio->crossfade);
 512                }
 513
 514                ch = audio_get_first_idle_channel();
 515             }
 516
 517             if( ch ){
 518                audio_channel_init( ch, &clip->clip, audio->flags );
 519                audio_channel_group( ch, audio->group );
 520                audio_channel_fadein( ch, audio->crossfade );
 521                ch = audio_relinquish_channel( ch );
 522             }
 523          }
 524
 525          audio_unlock();
 526          return;
 527       }
 528    }
 529 }
 530
 531 VG_STATIC void entity_call( world_instance *world, ent_call *call )
 532 {
 533    if( call->ent.type == k_ent_volume ){
 534       ent_volume_call( world, call );
 535    } else if( call->ent.type == k_ent_audio ){
 536       ent_audio_call( world, call );
 537    }
 538 }
 539
 540 VG_STATIC void world_update( world_instance *world, v3f pos )
 541 {
 542    world_global.sky_time += world_global.sky_rate * vg.time_delta;
 543    world_global.sky_rate = vg_lerp( world_global.sky_rate,
 544                                     world_global.sky_target_rate,
 545                                     vg.time_delta * 5.0 );
 546
 547    world_routes_update_timer_texts( world );
 548    world_routes_update( world );
 549    //world_routes_debug( world );
 550
 551    /* ---- SFD ------------ */
 552
 553    if( mdl_arrcount( &world->ent_route ) ){
 554       u32 closest = 0;
 555       float min_dist = INFINITY;
 556
 557       for( u32 i=0; i<mdl_arrcount( &world->ent_route ); i++ ){
 558          ent_route *route = mdl_arritm( &world->ent_route, i );
 559          float dist = v3_dist2( route->board_transform[3], pos );
 560
 561          if( dist < min_dist ){
 562             min_dist = dist;
 563             closest = i;
 564          }
 565       }
 566
 567       if( (world_global.sfd.active_route_board != closest)
 568           || network_scores_updated )
 569       {
 570          network_scores_updated = 0;
 571          world_global.sfd.active_route_board = closest;
 572
 573          ent_route *route = mdl_arritm( &world->ent_route, closest );
 574          u32 id = route->official_track_id;
 575
 576          if( id != 0xffffffff ){
 577             struct netmsg_board *local_board =
 578                &scoreboard_client_data.boards[id];
 579
 580             for( int i=0; i<13; i++ ){
 581                sfd_encode( i, &local_board->data[27*i] );
 582             }
 583          }else{
 584             sfd_encode( 0, mdl_pstr( &world->meta, route->pstr_name ) );
 585             sfd_encode( 1, "No data" );
 586          }
 587       }
 588    }
 589    sfd_update();
 590
 591    static float random_accum = 0.0f;
 592    random_accum += vg.time_delta;
 593
 594    u32 random_ticks = 0;
 595
 596    while( random_accum > 0.1f ){
 597       random_accum -= 0.1f;
 598       random_ticks ++;
 599    }
 600
 601    float radius = 25.0f;
 602    boxf volume_proximity;
 603    v3_add( pos, (v3f){ radius, radius, radius }, volume_proximity[1] );
 604    v3_sub( pos, (v3f){ radius, radius, radius }, volume_proximity[0] );
 605
 606    bh_iter it;
 607    bh_iter_init( 0, &it );
 608    int idx;
 609
 610    int in_volume = 0;
 611
 612    while( bh_next( world->volume_bh, &it, volume_proximity, &idx ) ){
 613       ent_volume *volume = mdl_arritm( &world->ent_volume, idx );
 614
 615       boxf cube = {{-1.0f,-1.0f,-1.0f},{1.0f,1.0f,1.0f}};
 616
 617       if( volume->type == k_volume_subtype_trigger ){
 618          v3f local;
 619          m4x3_mulv( volume->to_local, pos, local );
 620
 621          if( (fabsf(local[0]) <= 1.0f) &&
 622              (fabsf(local[1]) <= 1.0f) &&
 623              (fabsf(local[2]) <= 1.0f) )
 624          {
 625             in_volume = 1;
 626             vg_line_boxf_transformed( volume->to_world, cube, 0xff00ff00 );
 627
 628             if( !world_global.in_volume ){
 629                ent_call basecall;
 630                basecall.ent.index = idx;
 631                basecall.ent.type = k_ent_volume;
 632                basecall.function = k_ent_function_trigger;
 633                basecall.data = NULL;
 634
 635                entity_call( world, &basecall );
 636             }
 637          }
 638          else
 639             vg_line_boxf_transformed( volume->to_world, cube, 0xff0000ff );
 640       }
 641       else if( volume->type == k_volume_subtype_particle ){
 642          vg_line_boxf_transformed( volume->to_world, cube, 0xff00c0ff );
 643
 644          for( int j=0; j<random_ticks; j++ ){
 645             ent_call basecall;
 646             basecall.ent.index = idx;
 647             basecall.ent.type = k_ent_volume;
 648             basecall.function = k_ent_function_trigger;
 649             basecall.data = NULL;
 650
 651             entity_call( world, &basecall );
 652          }
 653       }
 654    }
 655    world_global.in_volume = in_volume;
 656
 657 #if 0
 658    if( k_debug_light_indices )
 659    {
 660       for( int i=0; i<world->light_count; i++ ){
 661          struct world_light *light = &world->lights[i];
 662          struct classtype_world_light *inf = light->inf;
 663
 664          u32 colour = 0xff000000;
 665          u8 r = inf->colour[0] * 255.0f,
 666             g = inf->colour[1] * 255.0f,
 667             b = inf->colour[2] * 255.0f;
 668
 669          colour |= r;
 670          colour |= g << 8;
 671          colour |= b << 16;
 672
 673          vg_line_pt3( light->node->co, 0.25f, colour );
 674       }
 675    }
 676
 677 #endif
 678 }
 679
 680 /*
 681  * -----------------------------------------------------------------------------
 682  *                              API implementation
 683  * -----------------------------------------------------------------------------
 684  */
 685
 686 VG_STATIC void ray_world_get_tri( world_instance *world,
 687                                   ray_hit *hit, v3f tri[3] )
 688 {
 689    for( int i=0; i<3; i++ )
 690       v3_copy( world->scene_geo->arrvertices[ hit->tri[i] ].co, tri[i] );
 691 }
 692
 693 VG_STATIC int ray_world( world_instance *world,
 694                          v3f pos, v3f dir, ray_hit *hit )
 695 {
 696    return scene_raycast( world->scene_geo, world->geo_bh, pos, dir, hit );
 697 }
 698
 699 /*
 700  * Cast a sphere from a to b and see what time it hits
 701  */
 702 VG_STATIC int spherecast_world( world_instance *world,
 703                                 v3f pa, v3f pb, float r, float *t, v3f n )
 704 {
 705    bh_iter it;
 706    bh_iter_init( 0, &it );
 707
 708    boxf region;
 709    box_init_inf( region );
 710    box_addpt( region, pa );
 711    box_addpt( region, pb );
 712
 713    v3_add( (v3f){ r, r, r}, region[1], region[1] );
 714    v3_add( (v3f){-r,-r,-r}, region[0], region[0] );
 715
 716    v3f dir;
 717    v3_sub( pb, pa, dir );
 718
 719    v3f dir_inv;
 720    dir_inv[0] = 1.0f/dir[0];
 721    dir_inv[1] = 1.0f/dir[1];
 722    dir_inv[2] = 1.0f/dir[2];
 723
 724    int hit = -1;
 725    float min_t = 1.0f;
 726
 727    int idx;
 728    while( bh_next( world->geo_bh, &it, region, &idx ) ){
 729       u32 *ptri = &world->scene_geo->arrindices[ idx*3 ];
 730       v3f tri[3];
 731
 732       boxf box;
 733       box_init_inf( box );
 734
 735       for( int j=0; j<3; j++ ){
 736          v3_copy( world->scene_geo->arrvertices[ptri[j]].co, tri[j] );
 737          box_addpt( box, tri[j] );
 738       }
 739
 740       v3_add( (v3f){ r, r, r}, box[1], box[1] );
 741       v3_add( (v3f){-r,-r,-r}, box[0], box[0] );
 742
 743       if( !ray_aabb1( box, pa, dir_inv, 1.0f ) )
 744          continue;
 745
 746       float t;
 747       v3f n1;
 748       if( spherecast_triangle( tri, pa, dir, r, &t, n1 ) ){
 749          if( t < min_t ){
 750             min_t = t;
 751             hit = idx;
 752             v3_copy( n1, n );
 753          }
 754       }
 755    }
 756
 757    *t = min_t;
 758    return hit;
 759 }
 760
 761 VG_STATIC
 762 struct world_surface *world_tri_index_surface( world_instance *world,
 763                                                  u32 index )
 764 {
 765    for( int i=1; i<world->surface_count; i++ ){
 766       struct world_surface *surf = &world->surfaces[i];
 767
 768       if( (index >= surf->sm_geo.vertex_start) &&
 769           (index  < surf->sm_geo.vertex_start+surf->sm_geo.vertex_count ) )
 770       {
 771          return surf;
 772       }
 773    }
 774
 775    return &world->surfaces[0];
 776 }
 777
 778 VG_STATIC struct world_surface *world_contact_surface( world_instance *world,
 779                                                          rb_ct *ct )
 780 {
 781    return world_tri_index_surface( world, ct->element_id );
 782 }
 783
 784 VG_STATIC struct world_surface *ray_hit_surface( world_instance *world,
 785                                                  ray_hit *hit )
 786 {
 787    return world_tri_index_surface( world, hit->tri[0] );
 788 }
 789
 790 /*
 791  * -----------------------------------------------------------------------------
 792  *                              Audio sampling
 793  * -----------------------------------------------------------------------------
 794  */
 795
 796 VG_STATIC
 797 enum audio_sprite_type world_audio_sample_sprite_random(v3f origin, v3f output);
 798 VG_STATIC void world_audio_sample_distances( v3f co, int *index, float *value );
 799
 800 #include "audio.h"
 801
 802 /*
 803  * Trace out a random point, near the player to try and determine water areas
 804  */
 805 VG_STATIC
 806 enum audio_sprite_type world_audio_sample_sprite_random(v3f origin, v3f output)
 807 {
 808    v3f chance = { (vg_randf()-0.5f) * 30.0f,
 809                   8.0f,
 810                   (vg_randf()-0.5f) * 30.0f };
 811
 812    v3f pos;
 813    v3_add( chance, origin, pos );
 814
 815    ray_hit contact;
 816    contact.dist = vg_minf( 16.0f, pos[1] );
 817
 818    world_instance *world = get_active_world();
 819
 820    if( ray_world( world, pos, (v3f){0.0f,-1.0f,0.0f}, &contact ) ){
 821       struct world_surface *mat = ray_hit_surface( world, &contact );
 822
 823       if( mat->info.surface_prop == k_surface_prop_grass){
 824          v3_copy( contact.pos, output );
 825          return k_audio_sprite_type_grass;
 826       }
 827       else{
 828          return k_audio_sprite_type_none;
 829       }
 830    }
 831
 832    output[0] = pos[0];
 833    output[1] = 0.0f;
 834    output[2] = pos[2];
 835
 836    float dist = fabsf(output[1] - origin[1]);
 837
 838    if( world->water.enabled && dist<=40.0f )
 839       return k_audio_sprite_type_water;
 840    else
 841       return k_audio_sprite_type_none;
 842 }
 843
 844 VG_STATIC void world_audio_sample_distances( v3f co, int *index, float *value )
 845 {
 846    float inr3 = 0.57735027,
 847          inr2 = 0.70710678118;
 848
 849    v3f sample_directions[] = {
 850       { -1.0f,  0.0f,  0.0f },
 851       {  1.0f,  0.0f,  0.0f },
 852       {  0.0f,  0.0f,  1.0f },
 853       {  0.0f,  0.0f, -1.0f },
 854       {  0.0f,  1.0f,  0.0f },
 855       {  0.0f, -1.0f,  0.0f },
 856       { -inr3,  inr3,  inr3 },
 857       {  inr3,  inr3,  inr3 },
 858       { -inr3,  inr3, -inr3 },
 859       {  inr3,  inr3, -inr3 },
 860       { -inr2,  0.0f,  inr2 },
 861       {  inr2,  0.0f,  inr2 },
 862       { -inr2,  0.0f, -inr2 },
 863       {  inr2,  0.0f, -inr2 },
 864    };
 865
 866    static int si = 0;
 867    static float distances[16];
 868
 869    ray_hit ray;
 870    ray.dist = 5.0f;
 871
 872    v3f rc, rd, ro;
 873    v3_copy( sample_directions[ si ], rd );
 874    v3_add( co, (v3f){0.0f,1.5f,0.0f}, ro );
 875    v3_copy( ro, rc );
 876
 877    float dist = 200.0f;
 878
 879    for( int i=0; i<10; i++ ){
 880       if( ray_world( get_active_world(), rc, rd, &ray ) ){
 881          dist = (float)i*5.0f + ray.dist;
 882          break;
 883       }
 884       else{
 885          v3_muladds( rc, rd, ray.dist, rc );
 886       }
 887    }
 888
 889    distances[si] = dist;
 890
 891    if( vg_lines.draw ){
 892       for( int i=0; i<14; i++ ){
 893          if( distances[i] != 200.0f ){
 894             u32 colours[] = { VG__RED, VG__BLUE, VG__GREEN,
 895                               VG__CYAN, VG__YELOW, VG__PINK,
 896                               VG__WHITE };
 897
 898             u32 colour = colours[i%7];
 899
 900             v3f p1;
 901             v3_muladds( ro, sample_directions[i], distances[i], p1 );
 902             vg_line( ro, p1, colour );
 903             vg_line_pt3( p1, 0.1f, colour );
 904          }
 905       }
 906    }
 907
 908    *index = si;
 909    *value = dist;
 910
 911    si ++;
 912    if( si >= 14 )
 913       si = 0;
 914 }
 915
 916 #endif /* WORLD_H */