scene.h

   1 #ifndef SCENE_H
   2 #define SCENE_H
   3
   4 #include "common.h"
   5 #include "model.h"
   6 #include "bvh.h"
   7
   8 typedef struct scene scene;
   9
  10 struct scene
  11 {
  12    glmesh mesh;
  13
  14    mdl_vert *verts;
  15    u32 *indices;
  16
  17    bh_tree bhtris;
  18    u32 vertex_count,
  19        indice_count,
  20        vertex_cap,
  21        indice_cap;
  22
  23    boxf bbx;
  24
  25    u32 shadower_count,
  26        shadower_cap;
  27
  28    mdl_submesh submesh;
  29 };
  30
  31 #if 0
  32 GLuint tex_dual_noise;
  33 #endif
  34
  35 static void scene_init( scene *pscene )
  36 {
  37    pscene->verts = NULL;
  38    pscene->indices = NULL;
  39    pscene->vertex_count = 0;
  40    pscene->indice_count = 0;
  41    pscene->shadower_count = 0;
  42    pscene->shadower_cap = 0;
  43    pscene->submesh.indice_start = 0;
  44    pscene->submesh.indice_count = 0;
  45
  46    v3_fill( pscene->bbx[0],  999999.9f );
  47    v3_fill( pscene->bbx[1], -999999.9f );
  48
  49 #if 0
  50    static int noise_ready = 0;
  51    if( !noise_ready )
  52    {
  53       noise_ready = 1;
  54
  55       u8 *buf = malloc( 256*256*2 );
  56
  57       for( int i=0; i<256*256; i++ )
  58       {
  59          u8 val = rand()&0xff;
  60          buf[i*2] = val;
  61       }
  62
  63       for( int y=0; y<256; y++ )
  64       {
  65          for( int x=0; x<256; x++ )
  66          {
  67             u8 *pr = &buf[(y*256+x)*2],
  68                *pg = &buf[(((y+17)&0xff)*256+((x+37)&0xff))*2+1];
  69             *pg = *pr;
  70          }
  71       }
  72
  73       /* TODO: This texture should be delted somewhere */
  74       glGenTextures( 1, &tex_dual_noise );
  75       glBindTexture( GL_TEXTURE_2D, tex_dual_noise );
  76       glTexImage2D( GL_TEXTURE_2D, 0, GL_RG, 256, 256, 0, GL_RG,
  77             GL_UNSIGNED_BYTE, buf );
  78
  79       vg_tex2d_linear();
  80       vg_tex2d_repeat();
  81
  82       free( buf );
  83    }
  84 #endif
  85 }
  86
  87 /*
  88  * Append a model into the scene with a given transform
  89  */
  90 static void scene_add_submesh( scene *pscene, mdl_header *mdl,
  91       mdl_submesh *sm, m4x3f transform )
  92 {
  93    pscene->verts = buffer_reserve( pscene->verts, pscene->vertex_count,
  94          &pscene->vertex_cap, sm->vertex_count, sizeof(mdl_vert) );
  95    pscene->indices = buffer_reserve( pscene->indices, pscene->indice_count,
  96          &pscene->indice_cap, sm->indice_count, sizeof(u32) );
  97
  98    m3x3f normal_matrix;
  99    m3x3_copy( transform, normal_matrix );
 100    v3_normalize( normal_matrix[0] );
 101    v3_normalize( normal_matrix[1] );
 102    v3_normalize( normal_matrix[2] );
 103
 104    /* Transform and place vertices */
 105    mdl_vert *src_verts = mdl_submesh_vertices( mdl, sm );
 106    u32 *src_indices    = mdl_submesh_indices( mdl, sm );
 107
 108    boxf bbxnew;
 109    box_copy( sm->bbx, bbxnew );
 110    m4x3_transform_aabb( transform, bbxnew );
 111    box_concat( pscene->bbx, bbxnew );
 112
 113    for( u32 i=0; i<sm->vertex_count; i++ )
 114    {
 115       mdl_vert *pvert = &pscene->verts[ pscene->vertex_count+i ],
 116                *src = &src_verts[ i ];
 117
 118       m4x3_mulv( transform, src->co, pvert->co );
 119       m3x3_mulv( normal_matrix, src->norm, pvert->norm );
 120
 121       pvert->colour[0] = src->colour[0];
 122       pvert->colour[1] = src->colour[1];
 123       pvert->colour[2] = src->colour[2];
 124       pvert->colour[3] = src->colour[3];
 125       v2_copy( src->uv, pvert->uv );
 126    }
 127
 128    for( u32 i=0; i<sm->indice_count; i++ )
 129    {
 130       u32 *pidx = &pscene->indices[ pscene->indice_count+i ];
 131       *pidx = src_indices[i] + pscene->vertex_count;
 132    }
 133
 134    pscene->vertex_count += sm->vertex_count;
 135    pscene->indice_count += sm->indice_count;
 136 }
 137
 138 /*
 139  * One by one adders for simplified access (mostly procedural stuff)
 140  */
 141 static void scene_push_tri( scene *pscene, u32 tri[3] )
 142 {
 143    pscene->indices = buffer_reserve( pscene->indices, pscene->indice_count,
 144          &pscene->indice_cap, 3, sizeof(u32) );
 145
 146    u32 *dst = &pscene->indices[pscene->indice_count];
 147    dst[0] = tri[0];
 148    dst[1] = tri[1];
 149    dst[2] = tri[2];
 150
 151    pscene->indice_count += 3;
 152 }
 153
 154 static void scene_push_vert( scene *pscene, mdl_vert *v )
 155 {
 156    pscene->verts = buffer_reserve( pscene->verts, pscene->vertex_count,
 157          &pscene->vertex_cap, 1, sizeof(mdl_vert) );
 158
 159    pscene->verts[pscene->vertex_count ++] = *v;
 160 }
 161
 162 static void scene_copy_slice( scene *pscene, mdl_submesh *sm )
 163 {
 164    sm->indice_start = pscene->submesh.indice_start;
 165    sm->indice_count = pscene->indice_count - sm->indice_start;
 166
 167    sm->vertex_start = pscene->submesh.vertex_start;
 168    sm->vertex_count = pscene->vertex_count - sm->vertex_start;
 169
 170    pscene->submesh.indice_start = pscene->indice_count;
 171    pscene->submesh.vertex_start = pscene->vertex_count;
 172 }
 173
 174 static void scene_fix( scene *pscene )
 175 {
 176    buffer_fix( pscene->verts, pscene->vertex_count,
 177          &pscene->vertex_cap, sizeof( mdl_vert ));
 178
 179    buffer_fix( pscene->indices, pscene->indice_count,
 180          &pscene->indice_cap, sizeof( mdl_vert ));
 181 }
 182
 183 __attribute__((warn_unused_result))
 184 static int scene_upload( scene *pscene )
 185 {
 186    if( ! mesh_upload( &pscene->mesh,
 187          pscene->verts, pscene->vertex_count,
 188          pscene->indices, pscene->indice_count ) )
 189    {
 190       return 0;
 191    }
 192
 193    vg_info( "Scene upload\n" );
 194    vg_info( "   indices:%u\n", pscene->indice_count );
 195    vg_info( "   verts:%u\n", pscene->vertex_count );
 196
 197    return 1;
 198 }
 199
 200 static void scene_bind( scene *pscene )
 201 {
 202    mesh_bind( &pscene->mesh );
 203 }
 204
 205 static void scene_draw( scene *pscene )
 206 {
 207    mesh_drawn( 0, pscene->indice_count );
 208 }
 209
 210 static void scene_free_offline_buffers( scene *pscene )
 211 {
 212    free( pscene->verts );
 213    free( pscene->indices );
 214 }
 215
 216 static void scene_free( scene *pscene )
 217 {
 218    scene_free_offline_buffers( pscene );
 219    /* TODO: bvh */
 220 }
 221
 222 /*
 223  * BVH implementation
 224  */
 225
 226 static void scene_bh_expand_bound( void *user, boxf bound, u32 item_index )
 227 {
 228    scene *s = user;
 229    mdl_vert *pa = &s->verts[ s->indices[item_index*3+0] ],
 230             *pb = &s->verts[ s->indices[item_index*3+1] ],
 231             *pc = &s->verts[ s->indices[item_index*3+2] ];
 232
 233   box_addpt( bound, pa->co );
 234   box_addpt( bound, pb->co );
 235   box_addpt( bound, pc->co );
 236 }
 237
 238 static float scene_bh_centroid( void *user, u32 item_index, int axis )
 239 {
 240    scene *s = user;
 241    mdl_vert *pa = &s->verts[ s->indices[item_index*3+0] ],
 242             *pb = &s->verts[ s->indices[item_index*3+1] ],
 243             *pc = &s->verts[ s->indices[item_index*3+2] ];
 244
 245    return (pa->co[axis] + pb->co[axis] + pc->co[axis]) * (1.0f/3.0f);
 246 }
 247
 248 static void scene_bh_swap( void *user, u32 ia, u32 ib )
 249 {
 250    scene *s = user;
 251
 252    u32 *ti = &s->indices[ia*3];
 253    u32 *tj = &s->indices[ib*3];
 254
 255    u32 temp[3];
 256    temp[0] = ti[0];
 257    temp[1] = ti[1];
 258    temp[2] = ti[2];
 259
 260    ti[0] = tj[0];
 261    ti[1] = tj[1];
 262    ti[2] = tj[2];
 263
 264    tj[0] = temp[0];
 265    tj[1] = temp[1];
 266    tj[2] = temp[2];
 267 }
 268
 269 static void scene_bh_debug( void *user, u32 item_index )
 270 {
 271    scene *s = user;
 272    u32 idx = item_index*3;
 273    mdl_vert *pa = &s->verts[ s->indices[ idx+0 ] ],
 274             *pb = &s->verts[ s->indices[ idx+1 ] ],
 275             *pc = &s->verts[ s->indices[ idx+2 ] ];
 276
 277    vg_line( pa->co, pb->co, 0xff0000ff );
 278    vg_line( pb->co, pc->co, 0xff0000ff );
 279    vg_line( pc->co, pa->co, 0xff0000ff );
 280 }
 281
 282 static int scene_bh_ray( void *user, u32 index, v3f co, v3f dir, ray_hit *hit )
 283 {
 284    scene *s = user;
 285    v3f positions[3];
 286
 287    u32 *tri = &s->indices[ index*3 ];
 288
 289    for( int i=0; i<3; i++ )
 290       v3_copy( s->verts[tri[i]].co, positions[i] );
 291
 292    float t;
 293    if(ray_tri( positions, co, dir, &t ))
 294    {
 295       if( t < hit->dist )
 296       {
 297          hit->dist = t;
 298          hit->tri = tri;
 299          return 1;
 300       }
 301    }
 302
 303    return 0;
 304 }
 305
 306 static bh_system bh_system_scene =
 307 {
 308    .expand_bound = scene_bh_expand_bound,
 309    .item_centroid = scene_bh_centroid,
 310    .item_swap = scene_bh_swap,
 311    .item_debug = scene_bh_debug,
 312    .cast_ray = scene_bh_ray
 313 };
 314
 315 /*
 316  * An extra step is added onto the end to calculate the hit normal
 317  */
 318 static int scene_raycast( scene *s, v3f co, v3f dir, ray_hit *hit )
 319 {
 320    int count = bh_ray( &s->bhtris, 0, co, dir, hit );
 321
 322    if( count )
 323    {
 324       v3f v0, v1;
 325
 326       float *pa = s->verts[hit->tri[0]].co,
 327             *pb = s->verts[hit->tri[1]].co,
 328             *pc = s->verts[hit->tri[2]].co;
 329
 330       v3_sub( pa, pb, v0 );
 331       v3_sub( pc, pb, v1 );
 332       v3_cross( v1, v0, hit->normal );
 333       v3_normalize( hit->normal );
 334       v3_muladds( co, dir, hit->dist, hit->pos );
 335    }
 336
 337    return count;
 338 }
 339
 340 static void scene_bh_create( scene *s )
 341 {
 342    u32 triangle_count = s->indice_count / 3;
 343    bh_create( &s->bhtris, &bh_system_scene, s, triangle_count );
 344 }
 345
 346 #endif