Here is another testcase from our side(pcsx2) showing worst case scenario where the performance drop is massive on amd. Don't know how helpful will this be but I thought I'd post it here anyway.
In fact it's a long time work, we need to find out 1. what may effect the performance. 2. Can we fix it without other side effect.
Thanks for your patience!
Another year, still no progress (at least on the windows side). Cmon guys it's been 4 years, if you've given up on OpenGL, please just tell us? I get OpenGL is considered "old" now, but it's still widely used in the emulation community at least and is far more functional than DX11, we hate having to recommend that for our users, but we have little choice. We gave you a great test case (with a midrange GPU of 2018 being shamefully outperformed by a display adapter), surely you could work on something from that?
I look forward to hearing an update.
If you need another example of the performance issues, this was taken from a youtube video (dunno which one, it got passed around a bit) so you can use this as another example of the terrible OGL performance on windows.