gltfutils.py 文件源码

def draw_primitive(primitive, gltf,
                   modelview_matrix=None,
                   projection_matrix=None,
                   view_matrix=None,
                   normal_matrix=None):
    set_draw_state(primitive, gltf,
                   modelview_matrix=modelview_matrix,
                   projection_matrix=projection_matrix,
                   view_matrix=view_matrix,
                   normal_matrix=normal_matrix)
    index_accessor = gltf['accessors'][primitive['indices']]
    index_bufferView = gltf['bufferViews'][index_accessor['bufferView']]
    gl.glBindBuffer(index_bufferView['target'], index_bufferView['id'])
    gl.glDrawElements(primitive['mode'], index_accessor['count'], index_accessor['componentType'],
                      c_void_p(index_accessor['byteOffset']))
    global num_draw_calls
    num_draw_calls += 1
    if CHECK_GL_ERRORS:
        if gl.glGetError() != gl.GL_NO_ERROR:
            raise Exception('error drawing elements')