WinQuake draws directly to the primary surface and also does some other operations on that like setting the palette entries, etc.
Since the changes on the primary surface must be presented at once to mimic a real hardware, the frame time and the physical FPS won't be smooth (evenly distributed).
But it also means that the minimum FPS is 60, so the gameplay should be felt smooth.

You can enable option DirectXExt\PrimarySurfaceBatchedUpdate to batch primary surface updates. It's not perfect but the physical framerate is mostly 60 fps with that for me.

Dege wrote on 2024-06-20, 18:35:

WinQuake draws directly to the primary surface and also does some other operations on that like setting the palette entries, etc […]
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WinQuake draws directly to the primary surface and also does some other operations on that like setting the palette entries, etc.
Since the changes on the primary surface must be presented at once to mimic a real hardware, the frame time and the physical FPS won't be smooth (evenly distributed).
But it also means that the minimum FPS is 60, so the gameplay should be felt smooth.

You can enable option DirectXExt\PrimarySurfaceBatchedUpdate to batch primary surface updates. It's not perfect but the physical framerate is mostly 60 fps with that for me.

Right, PrimarySurfaceBatchedUpdate helps to an extent, the game is mostly smooth but I do get framerate drops every time the screen flashes (e.g. whenever you pick up an item).

However the game should be smooth without PrimarySurfaceBatchedUpdate as well, only the frametime graph looks bad because of the inserted extra frames.

It's not about the meters, the game is decidedly unsmooth visually and I tested it on two different GPUs. So there's something else going on.