Screen tearing and slowdown

[Guest]

I would need you to compile the build for me; I'm not equipped to build from source. I very much appreciate your help in trying to identify and resolve this issue.

[dpJudas]

You're welcome guest. I probably want this solved just as badly as you do. Here's the special build that does the post processing a little different: http://esoteric.clanlib.org/~mbn/DebugGZDoom.zip

The executable does some extra error checking after every single OpenGL operation during initialization of the render buffer code. If there's a problem creating any of the textures or anything like that, it should error out with a fatal message. I'm not really expecting this to happen in your case though as you don't seem to have the 'black screen' problem. The other thing it does is to use its own vertex buffer for rendering the screen quads - this is the part I'm wondering will change anything for you or not.

[Guest]

Thank you for this. I am sorry to report that I am still experiencing the issue all the same with this test build.

If there are any extra system specs or diagnostics I can offer to help you research the issue, I am happy to comply.

[dpJudas]

What version of Windows are you running? And what's the driver version you are using? We both have the same generation graphics card (mine is a 980gtx), which I would expect to behave somewhat the same.

[Guest]

I'm running Windows 10 64-bit, and GeForce Driver 368.81, which GeForce Experience tells me is up-to-date.

[dpJudas]

Running Windows 10 64-bit here too. Just tried with the 368.81 driver (ran some old may version) and everything works fine. I tried turning vsync off as that sounds like what you're using - still no dice. It did put a little smile on my face when I saw it peak at 1200 fps at 1920x1080 and 600 fps at 3840x2160 - Graf sure made this thing run fast.

Maybe there's something different about your ini file? If there's nothing personal in it, maybe if I can get a copy I could try with your exact settings. Grasping at straws here.

[Guest]

I was actually beginning to wonder if it was my .ini, as well, but I wouldn't even know where to begin looking in it... I'll attach it here.

[dpJudas]

Good news! Finally found something which I can only explain as a bug in the Nvidia driver. Apparently calling wglSwapIntervalEXT after other OpenGL commands related to frame buffers made it ignore the call completely. Here's a fixed version you can try test with: http://esoteric.clanlib.org/~mbn/DebugGZDoom2.zip

Pull request with the fix: https://github.com/coelckers/gzdoom/pull/78

[Guest]

This seems to have fixed it! Thank you so much for all your efforts. I'm very happy this could be resolved.

[Graf Zahl]

Indeed. This kind of bugs are the nastiest ones because you need a setup where the problem manifests itself.

[dpJudas]

That was one nasty bug.