Support for volumetric data when using OpenGL rendering

[Tomaubier]

Description of proposed feature

I'm currently working on a project where displaying volumetric data would be a real plus! I'm currently rendering Manim animations using OpenGL and considering that I use the OpenGL-based pyqtgraph package to perform such data visualisation, I'm wondering how hard it would be to implement such a feature in Manim.

How can the new feature be used?

A VolumeMobject would be implemented in a similar fashion as pyqtgraph's glvolumeitem.
For those not familiar with pyqtgraph, glvolumeitem allows to render such 3D fields:

Additional comments

I started looking into reimplementing glvolumeitem using pyglet, but my ignorance of OpenGL is not of a great help. If anyone of you wants to give it a try let me know!