- v2f v0, v1, v2, vp, vp2;
- float d, bca = 0.f, bcb = 0.f, bcc = 0.f;
-
- v0[0] = pB[0] - pA[0];
- v0[1] = pB[2] - pA[2];
- v1[0] = pC[0] - pA[0];
- v1[1] = pC[2] - pA[2];
- v2[0] = pB[0] - pC[0];
- v2[1] = pB[2] - pC[2];
-
- d = 1.f / (v0[0]*v1[1] - v1[0]*v0[1]);
-
-#if 0
- /* Backface culling */
- if( v2_cross( v0, v1 ) > 0.f )
- return;
-#endif
-
- vp[0] = ray[0] - pA[0];
- vp[1] = ray[2] - pA[2];
-
- if( v2_cross( v0, vp ) > 0.f ) return 0;
- if( v2_cross( vp, v1 ) > 0.f ) return 0;
-
- vp2[0] = ray[0] - pB[0];
- vp2[1] = ray[2] - pB[2];
-
- if( v2_cross( vp2, v2 ) > 0.f ) return 0;
-
- bcb = (vp[0]*v1[1] - v1[0]*vp[1]) * d;
- bcc = (v0[0]*vp[1] - vp[0]*v0[1]) * d;
- bca = 1.f - bcb - bcc;
-
- *height = pA[1]*bca + pB[1]*bcb + pC[1]*bcc;
- return 1;
-}
-
-/* Temporary */
-static int sample_scene_height( scene *pscene, v3f pos, v3f norm )
-{
- for( int i=0; i<pscene->indice_count/3; i++ )
- {
- u32 *tri = &pscene->indices[i*3];
-
- float *pA = pscene->verts[tri[0]].co,
- *pB = pscene->verts[tri[1]].co,
- *pC = pscene->verts[tri[2]].co;
-
- float height;
- if( triangle_raycast2d( pA, pB, pC, pos, &height ))
- {
- pos[1] = height;
-
- if( norm )
- {
- v3f v0, v1;
- v3_sub( pA, pB, v0 );
- v3_sub( pC, pB, v1 );
- v3_cross( v1, v0, norm );
- v3_normalize( norm );
- }
-
- return 1;
- }
- }
- return 0;
-}
-
-static void sample_scene_normal( scene *pscene, v3f pos, v3f normal )
-{
- for( int i=0; i<pscene->indice_count/3; i++ )
- {
- u32 *tri = &pscene->indices[i*3];
-
- float height;
- if( triangle_raycast2d(
- pscene->verts[ tri[0] ].co,
- pscene->verts[ tri[1] ].co,
- pscene->verts[ tri[2] ].co, pos, &height ))
- {
- v3f v0, v1;
-
- v3_sub( pscene->verts[ tri[1] ].co,
- pscene->verts[ tri[0] ].co,
- v0 );
-
- v3_sub( pscene->verts[ tri[2] ].co,
- pscene->verts[ tri[0] ].co,
- v1 );
-
- v3_cross( v0, v1, normal );
- v3_normalize( normal );
- return;
- }
- }
-
- normal[0] = 0.0f;
- normal[1] = 1.0f;
- normal[2] = 0.0f;
-}
-
-struct bvh_node
-{
- boxf bbx;
-
- /* if il is 0, this is a leaf */
- u32 il, count;
- union{ u32 ir, start; };
-};
-
-static void bvh_update_bounds( scene *s, u32 inode )
-{
- bvh_node *node = &s->bvh.nodes[ inode ];
-
- box_init_inf( node->bbx );
- for( u32 i=0; i<node->count; i++ )
- {
- u32 idx = node->start+i;
- model_vert *pa = &s->verts[ s->indices[idx*3+0] ],
- *pb = &s->verts[ s->indices[idx*3+1] ],
- *pc = &s->verts[ s->indices[idx*3+2] ];
-
- box_addpt( node->bbx, pa->co );
- box_addpt( node->bbx, pb->co );
- box_addpt( node->bbx, pc->co );
- }
-}
-
-static void bvh_subdiv( scene *s, u32 inode )
-{
- bvh_node *node = &s->bvh.nodes[ inode ];
-
- v3f extent;
- v3_sub( node->bbx[1], node->bbx[0], extent );
-
- int axis = 0;
- if( extent[1] > extent[0] ) axis = 1;
- if( extent[2] > extent[axis] ) axis = 2;
-
- float split = node->bbx[0][axis] + extent[axis]*0.5f;
-
- /* To beat: 121,687 / 136,579
- * 136,375
- */
-
- float avg = 0.0;
- for( u32 t=0; t<node->count; t++ )
- {
- u32 *ti = &s->indices[(node->start+t)*3];
- float a = s->verts[ti[0]].co[axis],
- b = s->verts[ti[1]].co[axis],
- c = s->verts[ti[2]].co[axis];
- avg += (a+b+c)/3.0;
- }
- avg /= (float)node->count;
-
- split = avg;
-
- i32 i = node->start,
- j = i + node->count-1;
-
- while( i <= j )
- {
- u32 *ti = &s->indices[i*3];
-
- float a = s->verts[ti[0]].co[axis],
- b = s->verts[ti[1]].co[axis],
- c = s->verts[ti[2]].co[axis];
-
- if( ((a+b+c) / 3.0f) < split )
- i ++;
- else
- {
- /* Swap triangle indices */
- u32 *tj = &s->indices[j*3];
- u32 temp[3];
- temp[0] = ti[0];
- temp[1] = ti[1];
- temp[2] = ti[2];
-
- ti[0] = tj[0];
- ti[1] = tj[1];
- ti[2] = tj[2];
-
- tj[0] = temp[0];
- tj[1] = temp[1];
- tj[2] = temp[2];
-
- j --;
- }
- }
-
- u32 left_count = i - node->start;
- if( left_count == 0 || left_count == node->count ) return;
-
- u32 il = s->bvh.node_count ++,
- ir = s->bvh.node_count ++;