Here is my attempt at making HD run on older GPUs. I haven't been able to actually test it on an older GPU yet, but this reduces the number of required SSBOs to within the minimum number guaranteed by the OpenGL spec. This doesn't guarantee that HD will run flawlessly, as there may be other unsolved bugs, but this means it might work. I've verified that it still runs on my system on both Linux and MacOS, and it seems to perform roughly the same. If anyone could do more thorough performance testing, that would be great! Also, if you happen to spot anything looking strange, make sure to mention it.
Here is my attempt at making HD run on older GPUs. I haven't been able to actually test it on an older GPU yet, but this reduces the number of required SSBOs to within the minimum number guaranteed by the OpenGL spec. This doesn't guarantee that HD will run flawlessly, as there may be other unsolved bugs, but this means it might work. I've verified that it still runs on my system on both Linux and MacOS, and it seems to perform roughly the same. If anyone could do more thorough performance testing, that would be great! Also, if you happen to spot anything looking strange, make sure to mention it.
Might fix #325, #145, #52, #41.