I am messing with Unity's cameras for a school project, my plan was to change the way that coordinates are projected onto the projection plane to a projection onto a sphere using sphere coordinates. But, getting to the actual math behind the cameras has been a bit of a pain.
My first method involved messing with render textures but, theoretically, that won't work because the camera has already rendered a texture which I am modifying.
Next I tried to get into the code for the base camera, maybe make a copy of the camera to modify without messing the original, but then I ran into this, the code that sets all of the camera's parameters for the editor, I saw the reference to a few .h files.
Where can I access these files? I found files with the same names but not related to Unity. They were also different from each-other, making me think that the file above isn't referring to some sort of industry standard, but it might be.
Unity is generally considered to be made up of two parts; the managed front end, and the unmanaged back end. The front end code (written in C#) can be studied on GitHub here. The unmanaged code (written in C++) is proprietary and isn't freely available.
Unity is fairly modifiable, but there are a number of rules you have to follow.
A camera workaround might be to work with the Scriptable Render Pipeline (e.g. URP). But I'm not sure this actually addresses what you're trying to achieve.