Frame pacing issues / perceived stutter in 2024.14.4 (fixed by disabling swapchain debug flags)

[mimclaudio-rgb]

Description

After updating to GameMaker 2024.14.4, projects exhibit noticeable frame pacing issues and perceived stuttering, even when FPS remains stable.

The issue is particularly visible in projects using camera smoothing (lerp) and visual effects.

The problem is resolved by disabling the new swapchain/present debug flags:

debug_event("WinWaitableSwapChainOff");
debug_event("WinPresentDoNotWaitOff");
debug_event("WinPresentRestartOff");

Steps To Reproduce

noone

Which version of GameMaker are you reporting this issue for?

IDE v2024.14.4.221 Runtime v2024.14.4.265

Which operating system(s) are you seeing the problem on?

Windows 10.0.19045.0

Which platform(s) are you seeing the problem on?

Windows

473c2ec8-79e9-4397-89a7-81d5a7a75111

[L-Clouds]

That's weird, I thought "waitable swapchains" were either outright not in use, or at least disabled by default: #12980 (comment)

[edit] The release notes say "Be aware that in all the above cases the default setting used in your game is “enabled”." What happened?
[edit 2] Explained in a follow-up comment by opera-mrennie: "Apologies, the release notes were wrong on this and have now been updated. The waitable swapchain code is not used and can't be re-enabled." #12980 (comment)

[mimclaudio-rgb]

Update / Additional Findings

After further testing, I was able to isolate the exact cause of the issue.

The frame pacing problem is specifically caused by the WinPresentDoNotWait flag.

Disabling only this flag resolves the issue completely:

debug_event("WinPresentDoNotWaitOff");

[opera-mrennie]

In tests when we added this flag it improved smoothness so it's strange that it has the opposite effect in this case. Since there is no project attached to this ticket we can specifically investigate we have decided to keep things as they are unless we get more reports of the same problem. If you find that using debug_event("WinPresentDoNotWaitOff") works for you then keep using it, though it might make sense to test your game on other machines (if possible) to see if they have similar results with that flag turned on and off, and possibly add it as a selectable option in your game.