--- /dev/null
+#include "scene.h"
+
+u32 scene_mem_required( scene_context *ctx )
+{
+ u32 vertex_length = vg_align8(ctx->max_vertices * sizeof(scene_vert)),
+ index_length = vg_align8(ctx->max_indices * sizeof(u32));
+
+ return vertex_length + index_length;
+}
+
+void scene_init( scene_context *ctx, u32 max_vertices, u32 max_indices )
+{
+ ctx->vertex_count = 0;
+ ctx->indice_count = 0;
+ ctx->max_vertices = max_vertices;
+ ctx->max_indices = max_indices;
+ ctx->arrindices = NULL; /* must be filled out by user */
+ ctx->arrvertices = NULL;
+
+ memset( &ctx->submesh, 0, sizeof(mdl_submesh) );
+
+ v3_fill( ctx->bbx[0], 999999.9f );
+ v3_fill( ctx->bbx[1], -999999.9f );
+}
+
+void scene_supply_buffer( scene_context *ctx, void *buffer )
+{
+ u32 vertex_length = vg_align8( ctx->max_vertices * sizeof(scene_vert) );
+
+ ctx->arrvertices = buffer;
+ ctx->arrindices = (u32*)(((u8*)buffer) + vertex_length);
+}
+
+void scene_vert_pack_norm( scene_vert *vert, v3f norm, f32 blend )
+{
+ v3f n;
+ v3_muls( norm, 127.0f, n );
+ v3_minv( n, (v3f){ 127.0f, 127.0f, 127.0f }, n );
+ v3_maxv( n, (v3f){ -127.0f, -127.0f, -127.0f }, n );
+ vert->norm[0] = n[0];
+ vert->norm[1] = n[1];
+ vert->norm[2] = n[2];
+ vert->norm[3] = blend * 127.0f;
+}
+
+/*
+ * Append a model into the scene with a given transform
+ */
+void scene_add_mdl_submesh( scene_context *ctx, mdl_context *mdl,
+ mdl_submesh *sm, m4x3f transform )
+{
+ if( ctx->vertex_count + sm->vertex_count > ctx->max_vertices ){
+ vg_fatal_error( "Scene vertex buffer overflow (%u exceeds %u)\n",
+ ctx->vertex_count + sm->vertex_count,
+ ctx->max_vertices );
+ }
+
+ if( ctx->indice_count + sm->indice_count > ctx->max_indices ){
+ vg_fatal_error( "Scene index buffer overflow (%u exceeds %u)\n",
+ ctx->indice_count + sm->indice_count,
+ ctx->max_indices );
+ }
+
+ mdl_vert *src_verts = mdl_arritm( &mdl->verts, sm->vertex_start );
+ scene_vert *dst_verts = &ctx->arrvertices[ ctx->vertex_count ];
+
+ u32 *src_indices = mdl_arritm( &mdl->indices, sm->indice_start ),
+ *dst_indices = &ctx->arrindices[ ctx->indice_count ];
+
+ /* Transform and place vertices */
+ boxf bbxnew;
+ box_init_inf( bbxnew );
+ m4x3_expand_aabb_aabb( transform, bbxnew, sm->bbx );
+ box_concat( ctx->bbx, bbxnew );
+
+ m3x3f normal_matrix;
+ m3x3_copy( transform, normal_matrix );
+ v3_normalize( normal_matrix[0] );
+ v3_normalize( normal_matrix[1] );
+ v3_normalize( normal_matrix[2] );
+
+ for( u32 i=0; i<sm->vertex_count; i++ ){
+ mdl_vert *src = &src_verts[i];
+ scene_vert *pvert = &dst_verts[i];
+
+ m4x3_mulv( transform, src->co, pvert->co );
+
+ v3f normal;
+ m3x3_mulv( normal_matrix, src->norm, normal );
+ scene_vert_pack_norm( pvert, normal, src->colour[0]*(1.0f/255.0f) );
+
+ v2_copy( src->uv, pvert->uv );
+ }
+
+ u32 real_indices = 0;
+ for( u32 i=0; i<sm->indice_count/3; i++ ){
+ u32 *src = &src_indices[i*3],
+ *dst = &dst_indices[real_indices];
+
+ v3f ab, ac, tn;
+ v3_sub( src_verts[src[2]].co, src_verts[src[0]].co, ab );
+ v3_sub( src_verts[src[1]].co, src_verts[src[0]].co, ac );
+ v3_cross( ac, ab, tn );
+
+#if 0
+ if( v3_length2( tn ) <= 0.00001f )
+ continue;
+#endif
+
+ dst[0] = src[0] + ctx->vertex_count;
+ dst[1] = src[1] + ctx->vertex_count;
+ dst[2] = src[2] + ctx->vertex_count;
+
+ real_indices += 3;
+ }
+
+ if( real_indices != sm->indice_count )
+ vg_warn( "Zero area triangles in model\n" );
+
+ ctx->vertex_count += sm->vertex_count;
+ ctx->indice_count += real_indices;
+}
+
+/*
+ * One by one adders for simplified access (mostly procedural stuff)
+ */
+void scene_push_tri( scene_context *ctx, u32 tri[3] )
+{
+ if( ctx->indice_count + 3 > ctx->max_indices )
+ vg_fatal_error( "Scene indice buffer overflow (%u exceeds %u)\n",
+ ctx->indice_count+3, ctx->max_indices );
+
+ u32 *dst = &ctx->arrindices[ ctx->indice_count ];
+
+ dst[0] = tri[0];
+ dst[1] = tri[1];
+ dst[2] = tri[2];
+
+ ctx->indice_count += 3;
+}
+
+void scene_push_vert( scene_context *ctx, scene_vert *v )
+{
+ if( ctx->vertex_count + 1 > ctx->max_vertices )
+ vg_fatal_error( "Scene vertex buffer overflow (%u exceeds %u)\n",
+ ctx->vertex_count+1, ctx->max_vertices );
+
+ scene_vert *dst = &ctx->arrvertices[ ctx->vertex_count ];
+ *dst = *v;
+
+ ctx->vertex_count ++;
+}
+
+void scene_copy_slice( scene_context *ctx, mdl_submesh *sm )
+{
+ sm->indice_start = ctx->submesh.indice_start;
+ sm->indice_count = ctx->indice_count - sm->indice_start;
+
+ sm->vertex_start = ctx->submesh.vertex_start;
+ sm->vertex_count = ctx->vertex_count - sm->vertex_start;
+
+ ctx->submesh.indice_start = ctx->indice_count;
+ ctx->submesh.vertex_start = ctx->vertex_count;
+}
+
+void scene_set_vertex_flags( scene_context *ctx,
+ u32 start, u32 count, u16 flags )
+{
+ for( u32 i=0; i<count; i++ )
+ ctx->arrvertices[ start + i ].flags = flags;
+}
+
+struct scene_upload_info{
+ scene_context *ctx;
+ glmesh *mesh;
+};
+
+void async_scene_upload( void *payload, u32 size )
+{
+ struct scene_upload_info *info = payload;
+
+ //assert( mesh->loaded == 0 );
+
+ glmesh *mesh = info->mesh;
+ scene_context *ctx = info->ctx;
+
+ glGenVertexArrays( 1, &mesh->vao );
+ glGenBuffers( 1, &mesh->vbo );
+ glGenBuffers( 1, &mesh->ebo );
+ glBindVertexArray( mesh->vao );
+
+ size_t stride = sizeof(scene_vert);
+
+ glBindBuffer( GL_ARRAY_BUFFER, mesh->vbo );
+ glBufferData( GL_ARRAY_BUFFER, ctx->vertex_count*stride,
+ ctx->arrvertices, GL_STATIC_DRAW );
+
+ glBindVertexArray( mesh->vao );
+ glBindBuffer( GL_ELEMENT_ARRAY_BUFFER, mesh->ebo );
+ glBufferData( GL_ELEMENT_ARRAY_BUFFER, ctx->indice_count*sizeof(u32),
+ ctx->arrindices, GL_STATIC_DRAW );
+
+ /* 0: coordinates */
+ glVertexAttribPointer( 0, 3, GL_FLOAT, GL_FALSE, stride, (void*)0 );
+ glEnableVertexAttribArray( 0 );
+
+ /* 1: normal */
+ glVertexAttribPointer( 1, 4, GL_BYTE, GL_TRUE,
+ stride, (void *)offsetof(scene_vert, norm) );
+ glEnableVertexAttribArray( 1 );
+
+ /* 2: uv */
+ glVertexAttribPointer( 2, 2, GL_FLOAT, GL_FALSE,
+ stride, (void *)offsetof(scene_vert, uv) );
+ glEnableVertexAttribArray( 2 );
+
+ VG_CHECK_GL_ERR();
+
+ mesh->indice_count = ctx->indice_count;
+ mesh->loaded = 1;
+
+ vg_info( "Scene upload ( XYZ_f32 UV_f32 XYZW_i8 )[ u32 ]\n" );
+ vg_info( " indices:%u\n", ctx->indice_count );
+ vg_info( " verts:%u\n", ctx->vertex_count );
+}
+
+void scene_upload_async( scene_context *ctx, glmesh *mesh )
+{
+ vg_async_item *call = vg_async_alloc( sizeof(struct scene_upload_info) );
+
+ struct scene_upload_info *info = call->payload;
+ info->mesh = mesh;
+ info->ctx = ctx;
+
+ vg_async_dispatch( call, async_scene_upload );
+}
+
+vg_async_item *scene_alloc_async( scene_context *scene, glmesh *mesh,
+ u32 max_vertices, u32 max_indices )
+{
+ scene_init( scene, max_vertices, max_indices );
+ u32 buf_size = scene_mem_required( scene );
+
+ u32 hdr_size = vg_align8(sizeof(struct scene_upload_info));
+ vg_async_item *call = vg_async_alloc( hdr_size + buf_size );
+
+ struct scene_upload_info *info = call->payload;
+
+ info->mesh = mesh;
+ info->ctx = scene;
+
+ void *buffer = ((u8*)call->payload)+hdr_size;
+ scene_supply_buffer( scene, buffer );
+
+ return call;
+}
+
+
+/*
+ * BVH implementation
+ */
+
+static void scene_bh_expand_bound( void *user, boxf bound, u32 item_index )
+{
+ scene_context *s = user;
+ scene_vert *pa = &s->arrvertices[ s->arrindices[item_index*3+0] ],
+ *pb = &s->arrvertices[ s->arrindices[item_index*3+1] ],
+ *pc = &s->arrvertices[ s->arrindices[item_index*3+2] ];
+
+ box_addpt( bound, pa->co );
+ box_addpt( bound, pb->co );
+ box_addpt( bound, pc->co );
+}
+
+static float scene_bh_centroid( void *user, u32 item_index, int axis )
+{
+ scene_context *s = user;
+ scene_vert *pa = &s->arrvertices[ s->arrindices[item_index*3+0] ],
+ *pb = &s->arrvertices[ s->arrindices[item_index*3+1] ],
+ *pc = &s->arrvertices[ s->arrindices[item_index*3+2] ];
+
+ #if 0
+
+ float min, max;
+
+ min = vg_minf( pa->co[axis], pb->co[axis] );
+ max = vg_maxf( pa->co[axis], pb->co[axis] );
+ min = vg_minf( min, pc->co[axis] );
+ max = vg_maxf( max, pc->co[axis] );
+
+ return (min+max) * 0.5f;
+
+ #else
+ return (pa->co[axis] + pb->co[axis] + pc->co[axis]) * (1.0f/3.0f);
+ #endif
+}
+
+static void scene_bh_swap( void *user, u32 ia, u32 ib )
+{
+ scene_context *s = user;
+
+ u32 *ti = &s->arrindices[ia*3];
+ u32 *tj = &s->arrindices[ib*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];
+}
+
+static void scene_bh_debug( void *user, u32 item_index )
+{
+ scene_context *s = user;
+ u32 idx = item_index*3;
+ scene_vert *pa = &s->arrvertices[ s->arrindices[ idx+0 ] ],
+ *pb = &s->arrvertices[ s->arrindices[ idx+1 ] ],
+ *pc = &s->arrvertices[ s->arrindices[ idx+2 ] ];
+
+ vg_line( pa->co, pb->co, 0xff0000ff );
+ vg_line( pb->co, pc->co, 0xff0000ff );
+ vg_line( pc->co, pa->co, 0xff0000ff );
+}
+
+static void scene_bh_closest( void *user, u32 index, v3f point, v3f closest )
+{
+ scene_context *s = user;
+
+ v3f positions[3];
+ u32 *tri = &s->arrindices[ index*3 ];
+ for( int i=0; i<3; i++ )
+ v3_copy( s->arrvertices[tri[i]].co, positions[i] );
+
+ closest_on_triangle_1( point, positions, closest );
+}
+
+bh_system bh_system_scene =
+{
+ .expand_bound = scene_bh_expand_bound,
+ .item_centroid = scene_bh_centroid,
+ .item_closest = scene_bh_closest,
+ .item_swap = scene_bh_swap,
+ .item_debug = scene_bh_debug,
+};
+
+/*
+ * An extra step is added onto the end to calculate the hit normal
+ */
+int scene_raycast( scene_context *s, bh_tree *bh,
+ v3f co, v3f dir, ray_hit *hit, u16 ignore )
+{
+ hit->tri = NULL;
+
+ bh_iter it;
+ bh_iter_init_ray( 0, &it, co, dir, hit->dist );
+ i32 idx;
+
+ while( bh_next( bh, &it, &idx ) ){
+ u32 *tri = &s->arrindices[ idx*3 ];
+
+ if( s->arrvertices[tri[0]].flags & ignore ) continue;
+
+ v3f vs[3];
+ for( u32 i=0; i<3; i++ )
+ v3_copy( s->arrvertices[tri[i]].co, vs[i] );
+
+ f32 t;
+ if( ray_tri( vs, co, dir, &t, 0 ) ){
+ if( t < hit->dist ){
+ hit->dist = t;
+ hit->tri = tri;
+ }
+ }
+ }
+
+ if( hit->tri ){
+ v3f v0, v1;
+
+ float *pa = s->arrvertices[hit->tri[0]].co,
+ *pb = s->arrvertices[hit->tri[1]].co,
+ *pc = s->arrvertices[hit->tri[2]].co;
+
+ v3_sub( pa, pb, v0 );
+ v3_sub( pc, pb, v1 );
+ v3_cross( v1, v0, hit->normal );
+ v3_normalize( hit->normal );
+ v3_muladds( co, dir, hit->dist, hit->pos );
+ }
+
+ return hit->tri?1:0;
+}
+
+bh_tree *scene_bh_create( void *lin_alloc, scene_context *s )
+{
+ u32 triangle_count = s->indice_count / 3;
+ return bh_create( lin_alloc, &bh_system_scene, s, triangle_count, 2 );
+}