C++ MeshPrimitive::getGroupedVertexElementsCount方法代码示例

// =======================================================================
// Read all faces from TRIANGLES, TRIANGLE_FANS, POLYLIST, POLYGON
// Important: This function MUST be called before read_lines() 
// Otherwise we will loose all edges from faces (see read_lines() above)
//
// TODO: import uv set names
// ========================================================================
void MeshImporter::read_polys(COLLADAFW::Mesh *collada_mesh, Mesh *me)
{
	unsigned int i;
	
	allocate_poly_data(collada_mesh, me);

	UVDataWrapper uvs(collada_mesh->getUVCoords());
	VCOLDataWrapper vcol(collada_mesh->getColors());

	MPoly *mpoly = me->mpoly;
	MLoop *mloop = me->mloop;
	int loop_index = 0;

	MaterialIdPrimitiveArrayMap mat_prim_map;

	COLLADAFW::MeshPrimitiveArray& prim_arr = collada_mesh->getMeshPrimitives();
	COLLADAFW::MeshVertexData& nor = collada_mesh->getNormals();

	for (i = 0; i < prim_arr.getCount(); i++) {
		
		COLLADAFW::MeshPrimitive *mp = prim_arr[i];

		// faces
		size_t prim_totpoly                           = mp->getFaceCount();
		unsigned int *position_indices                = mp->getPositionIndices().getData();
		unsigned int *normal_indices                  = mp->getNormalIndices().getData();


		bool mp_has_normals = primitive_has_useable_normals(mp);
		bool mp_has_faces   = primitive_has_faces(mp);

		int collada_meshtype = mp->getPrimitiveType();
		
		// since we cannot set mpoly->mat_nr here, we store a portion of me->mpoly in Primitive
		Primitive prim = {mpoly, 0};

		// If MeshPrimitive is TRIANGLE_FANS we split it into triangles
		// The first trifan vertex will be the first vertex in every triangle
		// XXX The proper function of TRIANGLE_FANS is not tested!!!
		// XXX In particular the handling of the normal_indices looks very wrong to me
		if (collada_meshtype == COLLADAFW::MeshPrimitive::TRIANGLE_FANS) {
			unsigned grouped_vertex_count = mp->getGroupedVertexElementsCount();
			for (unsigned int group_index = 0; group_index < grouped_vertex_count; group_index++) {
				unsigned int first_vertex = position_indices[0]; // Store first trifan vertex
				unsigned int first_normal = normal_indices[0]; // Store first trifan vertex normal
				unsigned int vertex_count = mp->getGroupedVerticesVertexCount(group_index);

				for (unsigned int vertex_index = 0; vertex_index < vertex_count - 2; vertex_index++) {
					// For each triangle store indeces of its 3 vertices
					unsigned int triangle_vertex_indices[3] = {first_vertex, position_indices[1], position_indices[2]};
					set_poly_indices(mpoly, mloop, loop_index, triangle_vertex_indices, 3);

					if (mp_has_normals) {  // vertex normals, same inplementation as for the triangles
						// the same for vertces normals
						unsigned int vertex_normal_indices[3] = {first_normal, normal_indices[1], normal_indices[2]};
						if (!is_flat_face(vertex_normal_indices, nor, 3))
							mpoly->flag |= ME_SMOOTH;
						normal_indices++;
					}
				
					mpoly++;
					mloop += 3;
					loop_index += 3;
					prim.totpoly++;

				}

				// Moving cursor  to the next triangle fan.
				if (mp_has_normals)
					normal_indices += 2;

				position_indices +=  2;
			}
		}

		if (collada_meshtype == COLLADAFW::MeshPrimitive::POLYLIST ||
			collada_meshtype == COLLADAFW::MeshPrimitive::POLYGONS ||
			collada_meshtype == COLLADAFW::MeshPrimitive::TRIANGLES) {
			COLLADAFW::Polygons *mpvc = (COLLADAFW::Polygons *)mp;
			unsigned int start_index = 0;

			COLLADAFW::IndexListArray& index_list_array_uvcoord = mp->getUVCoordIndicesArray();
			COLLADAFW::IndexListArray& index_list_array_vcolor  = mp->getColorIndicesArray();

			for (unsigned int j = 0; j < prim_totpoly; j++) {
				
				// Vertices in polygon:
				int vcount = get_vertex_count(mpvc, j);
				set_poly_indices(mpoly, mloop, loop_index, position_indices, vcount);


				for (unsigned int uvset_index = 0; uvset_index < index_list_array_uvcoord.getCount(); uvset_index++) {
					// get mtface by face index and uv set index
//.........这里部分代码省略.........