code: def on_draw(self, event):
      gloo.clear()
      self.program.draw("triangles", faces_buffer)
  
file_path: vispy/examples/demo/gloo/glsl_sandbox_cube.py
imports: import numpy
  from vispy import app, gloo
  from vispy.io import read_mesh, load_data_file, load_crate
  from vispy.util.transforms import perspective, translate, rotate
label_desc: Use image node_id 3 for calling the Canvas obj's underlying member method code with example usage: obj.on_draw(event) without return types