Cleanup OpenGL Renderer

[SarahCosmosys]

I think the OpenGL renderer could benefit from a bit of cleanup. It would make it easier to maintain, fix bugs, and add new features. There are a few things which would help, one of which is assuming OpenGL 2.1 as a requirement. I think that this isn't a tall requirement for older machines (2.1 is supported on most things, expect for really old hardware). It would reduce version-based spaghetti code and make it easier to work with in general. I am willing to provide a PR for this, I'm just curious about peoples opinions on this.

[kraflab]

This port is in maintenance mode, so reworking the renderer is a bit outside scope. This is being done in dsda-doom though, gradually over time.

[fabiangreffrath]

Well, if this would mean to merely strip out some if/then/else spaghetti code, I'd be open to it. But, as @kraflab stated, if this involves rewriting (parts of) the renderer, then this is the wrong project, because there will be noone to maintain the changes.

[kraflab]

It's also important to preserve the compatibility prboom+ has with old hardware I think, unless it becomes necessary to remove it.

[JadingTsunami]

What's proposed reads to me more like "modernize the OpenGL renderer" vs. "clean up", but more specifics may be needed to fairly evaluate.

Either way I agree that if this port is in "maintenance mode" then any such work is outside the scope of that.

[yum13241]

OpenGL just doesn't appear as an option on my setup. Video Mode shows 8bit, 16bit, 32bit, but no OpenGL. I got my build from the chaotic aur.

[JadingTsunami]

OpenGL just doesn't appear as an option on my setup. Video Mode shows 8bit, 16bit, 32bit, but no OpenGL. I got my build from the chaotic aur.

I'd suggest you work with the maintainers of that packaging system to update to the latest version of PrBoom-Plus as a first step. The binaries were separate in older versions. Updating to the latest would resolve that.