Question about OpenGL rendering size

[tlpss]

It seems that the OpenGL rendering size is set once for mujoco enviroments instead of using the actual width and height provided to the MujocoRenderer

Gymnasium/gymnasium/envs/mujoco/mujoco_env.py

Line 124 in cde2f60

model.vis.global_.offwidth = self.width

I used the MujocoRenderer to create a custom renderer with a different size, but this causes black bands on the part outside of the original size.

    renderer = MujocoRenderer(
        env.unwrapped.model,
        env.unwrapped.data, 
        None,
        width=width,
        height=height,
        camera_name=camera_name,
    )
img = renderer.render(render_mode)

Shouldn't the OpenGL size be set inside the renderer before creating the screen? i.e. here

I changed the code like his

                # save the original width and height of the model to restore it later
                orig_width = self.model.vis.global_.offwidth
                orig_height = self.model.vis.global_.offheight

                # set the width and height to the context, otherswise the rendering will have black bands if the resolution differs from the one     with which the gym env was created.
                self.model.vis.global_.offwidth = self.width
                self.model.vis.global_.offheight = self.height

                self.viewer = OffScreenViewer(
                    self.model,
                    self.data,
                    self.width,
                    self.height,
                    self.max_geom,
                    self._vopt,
                )

                # restore the default  width and height to the context
                self.model.vis.global_.offwidth = orig_width
                self.model.vis.global_.offheight = orig_height

which solved the black bands for me:

Not an expert on mujoco rendering though, so I might be overlooking something.

[pseudo-rnd-thoughts]

@tlpss Thanks for reporting the issue, could you provide a short script to reproduce the issue?