+ v3_copy( world->scene_geo.arrvertices[ hit->tri[i] ].co, tri[i] );
+}
+
+VG_STATIC int ray_world( world_instance *world,
+ v3f pos, v3f dir, ray_hit *hit )
+{
+ return scene_raycast( &world->scene_geo, world->geo_bh, pos, dir, hit );
+}
+
+/*
+ * Cast a sphere from a to b and see what time it hits
+ */
+VG_STATIC int spherecast_world( world_instance *world,
+ v3f pa, v3f pb, float r, float *t, v3f n )
+{
+ bh_iter it;
+ bh_iter_init( 0, &it );
+
+ boxf region;
+ box_init_inf( region );
+ box_addpt( region, pa );
+ box_addpt( region, pb );
+
+ v3_add( (v3f){ r, r, r}, region[1], region[1] );
+ v3_add( (v3f){-r,-r,-r}, region[0], region[0] );
+
+ v3f dir;
+ v3_sub( pb, pa, dir );
+
+ v3f dir_inv;
+ dir_inv[0] = 1.0f/dir[0];
+ dir_inv[1] = 1.0f/dir[1];
+ dir_inv[2] = 1.0f/dir[2];
+
+ int hit = -1;
+ float min_t = 1.0f;
+
+ int idx;
+ while( bh_next( world->geo_bh, &it, region, &idx ) ){
+ u32 *ptri = &world->scene_geo.arrindices[ idx*3 ];
+ v3f tri[3];
+
+ boxf box;
+ box_init_inf( box );
+
+ for( int j=0; j<3; j++ ){
+ v3_copy( world->scene_geo.arrvertices[ptri[j]].co, tri[j] );
+ box_addpt( box, tri[j] );
+ }
+
+ v3_add( (v3f){ r, r, r}, box[1], box[1] );
+ v3_add( (v3f){-r,-r,-r}, box[0], box[0] );
+
+ if( !ray_aabb1( box, pa, dir_inv, 1.0f ) )
+ continue;
+
+ float t;
+ v3f n1;
+ if( spherecast_triangle( tri, pa, dir, r, &t, n1 ) ){
+ if( t < min_t ){
+ min_t = t;
+ hit = idx;
+ v3_copy( n1, n );
+ }
+ }
+ }
+
+ *t = min_t;
+ return hit;
+}
+
+VG_STATIC
+struct world_surface *world_tri_index_surface( world_instance *world,
+ u32 index )
+{
+ for( int i=1; i<world->surface_count; i++ ){
+ struct world_surface *surf = &world->surfaces[i];
+
+ if( (index >= surf->sm_geo.vertex_start) &&
+ (index < surf->sm_geo.vertex_start+surf->sm_geo.vertex_count ) )
+ {
+ return surf;
+ }
+ }
+
+ return &world->surfaces[0];
+}
+
+VG_STATIC struct world_surface *world_contact_surface( world_instance *world,
+ rb_ct *ct )
+{
+ return world_tri_index_surface( world, ct->element_id );