Stop using CDTs for OpenGL and run render test when Python tests are run

[traversaro]

mujoco should have full support for headless rendering, so I guess rendering tests should pass fine also in CI. This is important to ensure that testing of downstream libraries (such as conda-forge/gymnasium-feedstock#41) assume that mujoco render works in CI.

This PR also:

• Stop using CDTs and just use the glvnd-based libgl-devel to provide OpenGL on Linux
• Use mesalib and set MUJOCO_GL=osmesa to pass render tests on Linux as the EGL driver available on centos7 (the images used in CI) have some problems. In [v9] Enable tests gz-rendering-feedstock#35 we switched to use a newer docker images to avoid problems, but in the mujoco case installing mesalib and set MUJOCO_GL=osmesa is probably the easier solution.
• On macOS and Windows MUJOCO_GL=osmesa is not supported as it is explicitly not allowed in https://github.com/google-deepmind/mujoco/blob/3.2.4/python/mujoco/gl_context.py#L22 and macos and Windows-specific code for handling osmesa is missing in https://github.com/google-deepmind/mujoco/blob/3.2.4/src/render/glad/glad.c#L226-L244 and https://github.com/google-deepmind/mujoco/blob/3.2.4/src/render/glad/glad.c#L88-L97 . So, as done in upstream CI, so we skip rendering tests there by setting MUJOCO_GL=disable.

Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

[conda-forge-admin]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe/meta.yaml) and found it was in an excellent condition.

[traversaro]

We were able to reproduce the failures that we saw in conda-forge/gymnasium-feedstock#41 . Windows and osx are failing, while Linux is hanging.

[traversaro]

osx error:

_______________________ MuJoCoRenderTest.test_can_render _______________________

self = <mujoco.render_test.MuJoCoRenderTest testMethod=test_can_render>

    def setUp(self):
      super().setUp()
>     self.gl = mujoco.GLContext(640, 480)

../_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placeho/lib/python3.10/site-packages/mujoco/render_test.py:28: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
../_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placeho/lib/python3.10/site-packages/mujoco/cgl/__init__.py:47: in __init__
    cgl.CGLChoosePixelFormat(
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

args = (<mujoco.cgl.c_int_Array_17 object at 0x1050ee440>, <cparam 'P' (0x1050ee110)>, <cparam 'P' (0x1050ee610)>)
err = 10002

    def checked_func(*args):
      err = func(*args)
      if err:
>       raise CGLError(_CGLErrorString(err).decode())
E       mujoco.cgl.cgl.CGLError: invalid pixel format

../_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placeho/lib/python3.10/site-packages/mujoco/cgl/cgl.py:132: CGLError

Windows error:

2024-10-21T14:43:43.7355505Z ______________________ MuJoCoRenderTest.test_can_render _______________________
2024-10-21T14:43:43.7355938Z 
2024-10-21T14:43:43.7362898Z self = <mujoco.render_test.MuJoCoRenderTest testMethod=test_can_render>
2024-10-21T14:43:43.7363387Z 
2024-10-21T14:43:43.7367174Z     def test_can_render(self):
2024-10-21T14:43:43.7367893Z       """Test that the bindings can successfully render a simple image.
2024-10-21T14:43:43.7368371Z     
2024-10-21T14:43:43.7369191Z       This test sets up a basic MuJoCo rendering context similar to the example in
2024-10-21T14:43:43.7369753Z       https://mujoco.readthedocs.io/en/latest/programming#visualization
2024-10-21T14:43:43.7370275Z       It calls `mjr_rectangle` rather than `mjr_render` so that we can assert an
2024-10-21T14:43:43.7374141Z       exact rendered image without needing golden data. The purpose of this test
2024-10-21T14:43:43.7374778Z       is to ensure that the bindings can correctly return pixels in Python, rather
2024-10-21T14:43:43.7375603Z       than to test MuJoCo's rendering pipeline itself.
2024-10-21T14:43:43.7376091Z       """
2024-10-21T14:43:43.7376511Z     
2024-10-21T14:43:43.7377088Z       self.model = mujoco.MjModel.from_xml_string('<mujoco><worldbody/></mujoco>')
2024-10-21T14:43:43.7377602Z       self.data = mujoco.MjData(self.model)
2024-10-21T14:43:43.7381908Z     
2024-10-21T14:43:43.7382561Z       scene = mujoco.MjvScene(self.model, maxgeom=0)
2024-10-21T14:43:43.7383103Z       mujoco.mjv_updateScene(
2024-10-21T14:43:43.7383457Z           self.model, self.data, mujoco.MjvOption(), mujoco.MjvPerturb(),
2024-10-21T14:43:43.7383832Z           mujoco.MjvCamera(), mujoco.mjtCatBit.mjCAT_ALL, scene)
2024-10-21T14:43:43.7384146Z     
2024-10-21T14:43:43.7384480Z >     context = mujoco.MjrContext(self.model, mujoco.mjtFontScale.mjFONTSCALE_150)
2024-10-21T14:43:43.7384850Z E     mujoco.FatalError: gladLoadGL error
2024-10-21T14:43:43.7385042Z 
2024-10-21T14:43:43.7388603Z ..\_test_env\Lib\site-packages\mujoco\render_test.py:54: FatalError

[traversaro]

@conda-forge-admin please rerender

[h-vetinari]

If you want, you can get rid of that skip and all traces of pypy/python_impl

[traversaro]

I plan to do that in a follow up PR, thanks!