//разбор вершинного формата
void ParseVertexFormatChannel (Parser::Iterator channel_iter, VertexFormat& vertex_format)
{
static const char* METHOD_NAME = "media::geometry::XmlMeshLibraryLoader::ParseVertexFormatChannel";
const char *name = get<const char*> (*channel_iter, "name", ""),
*semantic_string = *name ? get<const char*> (*channel_iter, "semantic", "custom") : get<const char*> (*channel_iter, "semantic"),
*type_string = get<const char*> (*channel_iter, "type");
VertexAttributeSemantic semantic = get_vertex_attribute_semantic (semantic_string);
VertexAttributeType type = get_vertex_attribute_type (type_string);
unsigned int offset = get<unsigned int> (*channel_iter, "offset");
if (semantic == VertexAttributeSemantic_Num)
throw xtl::make_argument_exception (METHOD_NAME, "semantic", semantic_string);
if (type == VertexAttributeType_Num)
throw xtl::make_argument_exception (METHOD_NAME, "type", type_string);
vertex_format.AddAttribute (name, semantic, type, offset);
}
