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How to remove one frame of delay on my system?

PostPosted: 04 Dec 2018, 01:26
by ad8e
I'm writing vsync code and I'm trying to get my screen to tear, but I'm not able to. Instead, I always see one frame of delay and perfect frames, which means something is queueing up frames and swapping them. This seems to be caused by my OS or driver. My test system is Intel HD 4000, Windows 8.1, Thinkpad T530. I've tried both my laptop monitor and an external monitor.

There are two ways you can help me:
1. run "fullscreen tearing attempt.exe" and tell me if it tears on your system, since it doesn't tear on mine. Virus scan is here. [Editor's note: Make sure SHA-256 of attachment matches this scan] If it does tear, please say your OS and graphics card.
2. does anyone have some source code that does tear?

I set my Intel HD driver to "Use application settings", disabled double buffering in the application, then made my application fullscreen and changed the video mode to ensure that it wasn't borderless fullscreen. But I still see an exact one frame delay and no torn frames.

Re: How to remove one frame of delay on my system?

PostPosted: 05 Dec 2018, 16:10
by ad8e
Note: if you want to follow the editor's suggestion of checking the SHA-256 hash, the simplest way of doing so is to open up the folder with the .exe file, shift + right click on an empty space with nothing selected, click on "Open command window here", and type
Code: Select all
certUtil -hashfile "fullscreen tearing attempt.exe" SHA256

Alternatively, you can just reupload it to virustotal, which will automatically recalculate the SHA-256 hash, detect it's the same file, and send you back to the page I linked.

Re: How to remove one frame of delay on my system?

PostPosted: 10 Dec 2018, 20:01
by ad8e
Thanks to Chief Blur Buster, who ran it and got back to me privately. It doesn't tear on his system either, so I'll look for more solutions.

Re: How to remove one frame of delay on my system?

PostPosted: 10 Dec 2018, 22:41
by Chief Blur Buster
ad8e wrote:Thanks to Chief Blur Buster, who ran it and got back to me privately. It doesn't tear on his system either, so I'll look for more solutions.

That's correct.

I now suspect it's a GLFW issue. Many developers think tearlines are useless when there are two use cases; (1) lower input lag; and (2) raster demos such as Tearline Jedi.

Re: How to remove one frame of delay on my system?

PostPosted: 12 Dec 2018, 04:14
by ad8e
Issue was solved, thanks to Chief Blur Buster at http://discourse.glfw.org/t/how-to-forc ... c-off/1225.