Live Scene Viewer

Standard Usage

In addition to the offscreen renderer, Pyrender comes with a live scene viewer. In its standard invocation, calling the Viewer’s constructor will immediately pop a viewing window that you can navigate around in.

>>> pyrender.Viewer(scene)

By default, the viewer uses your scene’s lighting. If you’d like to start with some additional lighting that moves around with the camera, you can specify that with:

>>> pyrender.Viewer(scene, use_raymond_lighting=True)

For a full list of the many options that the Viewer supports, check out its documentation.

Running the Viewer in a Separate Thread

If you’d like to animate your models, you’ll want to run the viewer in a separate thread so that you can update the scene while the viewer is running. To do this, first pop the viewer in a separate thread by calling its constructor with the run_in_thread option set:

>>> v = pyrender.Viewer(scene, run_in_thread=True)

Then, you can manipulate the Scene while the viewer is running to animate things. However, be careful to acquire the viewer’s Viewer.render_lock before editing the scene to prevent data corruption:

>>> i = 0
>>> while True:
...     pose = np.eye(4)
...     pose[:3,3] = [i, 0, 0]
...     v.render_lock.acquire()
...     scene.set_pose(mesh_node, pose)
...     v.render_lock.release()
...     i += 0.01

You can wait on the viewer to be closed manually:

>>> while v.is_active:
...     pass

Or you can close it from the main thread forcibly. Make sure to still loop and block for the viewer to actually exit before using the scene object again.

>>> v.close_external()
>>> while v.is_active:
...     pass