const VertexArray *get_vertex_array() const { return vertex_array; }
const VertexArray *get_instance_array() const { return inst_array; }
const Buffer *get_index_buffer() const { return index_buffer; }
const VertexArray *get_vertex_array() const { return vertex_array; }
const VertexArray *get_instance_array() const { return inst_array; }
const Buffer *get_index_buffer() const { return index_buffer; }