[BUG] OpenGL App With Multiple Windows Doesn't Close Itself Cleanly

Bug Description

Repro on Windows:

import matplotlib
import matplotlib.animation
import matplotlib.pyplot
import numpy as np
import pyglet
import warp as wp
import warp.render


BOX_POINTS = np.array(
    (
        ( 0.853553, -0.146446,  0.0     ), ( 0.146446, -0.853553,  0.0     ),
        ( 0.353553,  0.353553,  0.707106), (-0.353553, -0.353553,  0.707106),
        (-0.353553, -0.353553, -0.707106), ( 0.353553,  0.353553, -0.707106),
        (-0.853553,  0.146446,  0.0     ), (-0.146446,  0.853553,  0.0     ),
    ),
    dtype=np.float32,
)

BOX_FACE_VERTEX_INDICES = np.array(
    (
        0, 3, 1, 0, 2, 3, 4, 7, 5, 4, 6, 7, 6, 2, 7, 6, 3, 2,
        5, 1, 4, 5, 0, 1, 5, 2, 0, 5, 7, 2, 1, 6, 4, 1, 3, 6,
    ),
    dtype=np.int32,
)

SPHERE_POINTS = (
    ( 0.0     ,  0.0     , -0.5     ), ( 0.0     ,  0.28656 , -0.425325),
    ( 0.249999,  0.081230, -0.425325), ( 0.0     ,  0.447213, -0.223606),
    ( 0.249999,  0.344095, -0.262865), ( 0.425325,  0.138196, -0.223606),
    ( 0.154508, -0.212662, -0.425325), ( 0.404508, -0.131432, -0.262865),
    ( 0.262865, -0.361803, -0.223606), (-0.154508, -0.212662, -0.425325),
    ( 0.0     , -0.425325, -0.262865), (-0.262865, -0.361803, -0.223606),
    (-0.249999,  0.081230, -0.425325), (-0.404508, -0.131432, -0.262865),
    (-0.425325,  0.138196, -0.223606), (-0.249999,  0.344095, -0.262865),
    (-0.154508,  0.475528,  0.0     ), (-0.404508,  0.293892,  0.0     ),
    (-0.262865,  0.361803,  0.223606), (-0.5     ,  0.0     ,  0.0     ),
    (-0.404508, -0.293892,  0.0     ), (-0.425325, -0.138196,  0.223606),
    (-0.154508, -0.475528,  0.0     ), ( 0.154508, -0.475528,  0.0     ),
    ( 0.0     , -0.447213,  0.223606), ( 0.404508, -0.293892,  0.0     ),
    ( 0.5     ,  0.0     ,  0.0     ), ( 0.425325, -0.138196,  0.223606),
    ( 0.404508,  0.293892,  0.0     ), ( 0.154508,  0.475528,  0.0     ),
    ( 0.262865,  0.361803,  0.223606), ( 0.0     ,  0.425325,  0.262865),
    (-0.404508,  0.131432,  0.262865), (-0.249999, -0.344095,  0.262865),
    ( 0.249999, -0.344095,  0.262865), ( 0.404508,  0.131432,  0.262865),
    ( 0.0     ,  0.0     ,  0.5     ), ( 0.154508,  0.212662,  0.425325),
    (-0.154508,  0.212662,  0.425325), ( 0.249999, -0.081230,  0.425325),
    ( 0.0     , -0.262865,  0.425325), (-0.249999, -0.081230,  0.425325),
)

SPHERE_FACE_VERTEX_INDICES = (
     2,  0,  1,  4,  1,  3,  5,  2,  4,  2,  1,  4,  6,  0,  2,  7,
     2,  5,  8,  6,  7,  6,  2,  7,  9,  0,  6, 10,  6,  8, 11,  9,
    10,  9,  6, 10, 12,  0,  9, 13,  9, 11, 14, 12, 13, 12,  9, 13,
     1,  0, 12, 15, 12, 14,  3,  1, 15,  1, 12, 15, 16,  3, 15, 17,
    15, 14, 18, 16, 17, 16, 15, 17, 19, 14, 13, 20, 13, 11, 21, 19,
    20, 19, 13, 20, 22, 11, 10, 23, 10,  8, 24, 22, 23, 22, 10, 23,
    25,  8,  7, 26,  7,  5, 27, 25, 26, 25,  7, 26, 28,  5,  4, 29,
     4,  3, 30, 28, 29, 28,  4, 29, 29,  3, 16, 31, 16, 18, 30, 29,
    31, 29, 16, 31, 17, 14, 19, 32, 19, 21, 18, 17, 32, 17, 19, 32,
    20, 11, 22, 33, 22, 24, 21, 20, 33, 20, 22, 33, 23,  8, 25, 34,
    25, 27, 24, 23, 34, 23, 25, 34, 26,  5, 28, 35, 28, 30, 27, 26,
    35, 26, 28, 35, 38, 36, 37, 31, 37, 30, 18, 38, 31, 38, 37, 31,
    37, 36, 39, 35, 39, 27, 30, 37, 35, 37, 39, 35, 39, 36, 40, 34,
    40, 24, 27, 39, 34, 39, 40, 34, 40, 36, 41, 33, 41, 21, 24, 40,
    33, 40, 41, 33, 41, 36, 38, 32, 38, 18, 21, 41, 32, 41, 38, 32,
)


resolution = (512, 384)
num_frames = 48
fps = 24
camera_pos = (0.0, 2.5, 5.0)
camera_front = (0.0, -0.5, -1.0)

image = wp.empty(shape=(resolution[1], resolution[0], 3), dtype=wp.float32)

geoms = (
    (BOX_POINTS, BOX_FACE_VERTEX_INDICES),
    (SPHERE_POINTS, SPHERE_FACE_VERTEX_INDICES),
)
renderers = (
    warp.render.OpenGLRenderer(
        fps=fps,
        screen_width=resolution[0],
        screen_height=resolution[1],
        camera_pos=camera_pos,
        camera_front=camera_front,
        vsync=True,
    ),
    warp.render.OpenGLRenderer(
        fps=fps,
        screen_width=resolution[0],
        screen_height=resolution[1],
        camera_pos=camera_pos,
        camera_front=camera_front,
        vsync=True,
    ),
)
renders = ([], [])

rng = np.random.default_rng(123)
for frame in range(num_frames):
    color = wp.sin(float(frame) * 0.05) * 0.5 + 0.5

    for i in range(2):
        renderers[i].begin_frame(frame / num_frames)
        renderers[i].render_mesh(
            "box",
            geoms[i][0],
            geoms[i][1],
            colors=(color, 0.5, 0.5),
        )
        renderers[i].end_frame()
        renderers[i].get_pixels(image, split_up_tiles=False, mode="rgb")
        renders[i].append(wp.clone(image, device="cpu", pinned=True))


for i in range(2):
    plot_fig = matplotlib.pyplot.figure(figsize=resolution, dpi=1.0)
    plot_fig.subplots_adjust(left=0, bottom=0, right=1, top=1)

    plot_img = matplotlib.pyplot.imshow(renders[i][0], animated=True)
    plot_img.axes.set_axis_off()

    plot_anim = matplotlib.animation.FuncAnimation(
        plot_fig,
        lambda frame: plot_img.set_data(renders[i][frame]),
        frames=num_frames,
        interval=(1.0 / 24.0) * 1000.0,
    )

    # matplotlib.pyplot.close()
    plot_anim.save(f"anim_{i + 1}.gif")

If we proactively close the windows ourselves, then everything is fine. However, if wait a few seconds for the windows to close themselves after the 48 frames are computed, then the following exceptions occur:

Exception ignored on calling ctypes callback function: <function Win32Window._get_window_proc.<locals>.f at 0x000001657FD0CE50>
Traceback (most recent call last):
  File ".venv\lib\site-packages\pyglet\window\win32\__init__.py", line 839, in f
  File ".venv\lib\site-packages\pyglet\window\win32\__init__.py", line 1277, in _event_killfocus
  File ".venv\lib\site-packages\pyglet\window\__init__.py", line 671, in dispatch_event
  File ".venv\lib\site-packages\pyglet\event.py", line 358, in dispatch_event
AssertionError:
Exception ignored in: <function ShapeInstancer.__del__ at 0x000001655D705FC0>
Traceback (most recent call last):
  File "warp\render\render_opengl.py", line 710, in __del__
  File ".venv\lib\site-packages\pyglet\gl\lib_wgl.py", line 56, in __call__
ImportError: sys.meta_path is None, Python is likely shutting down
Exception ignored on calling ctypes callback function: <function Win32Window._get_window_proc.<locals>.f at 0x000001655D7AED40>
Traceback (most recent call last):
  File ".venv\lib\site-packages\pyglet\window\win32\__init__.py", line 839, in f
  File ".venv\lib\site-packages\pyglet\window\win32\__init__.py", line 1277, in _event_killfocus
  File ".venv\lib\site-packages\pyglet\window\__init__.py", line 671, in dispatch_event
  File ".venv\lib\site-packages\pyglet\event.py", line 358, in dispatch_event
AssertionError:
Exception ignored in: <function ShapeInstancer.__del__ at 0x000001655D705FC0>
Traceback (most recent call last):
  File "warp\render\render_opengl.py", line 710, in __del__
  File ".venv\lib\site-packages\pyglet\gl\lib_wgl.py", line 56, in __call__
ImportError: sys.meta_path is None, Python is likely shutting down

System Information

No response

Start by running the Windows reproduction script with two OpenGLRenderer instances and inspect warp/render/render_opengl.py around ShapeInstancer.del at line 710, along with the pyglet window callbacks in the traceback. Done means the 48-frame, two-window workflow exits without the callback assertions or shutdown-time ImportError when windows close automatically.