GDC 2018 Videos Now Available, Including Khronos/Vulkan Talks

[phoronix]

Phoronix: GDC 2018 Videos Now Available, Including Khronos/Vulkan Talks

If you are looking for some deep technical content to watch this weekend, the video recordings from this month's Game Developers Conference 2018 (GDC 18) are now available...

http://www.phoronix.com/scan.php?page=news_item&px=GDC-2018-Videos-Online

[anth]

Alen Ladavac, the Croteam CTO, had a presentation titled "Advanced Graphics Techniques Tutorial: The Elusive Frame Timing: A Case for Smoothness Over Speed". He has tweeted the the GDC video player might not be quite good enough for this so will make the video downloadable.

I'll wait for the downloadable video, but the short version from reading the slides is reading the slides is 20fps with consistent timing is better than 60fps with erratic timing, and erratic timing is more of a problem now with deeply pipelined GPUs, compositors, etc. Solution is to drop the frame rate if needed to avoid stuttering.

Their prototype was only available on Nvidia and only on Linux; it proved the concept but wasn't quite there. Their next version "had everything" and requires vk_google_display_timing which is only available on a limited number of Android devices and in the RADV driver. They'd like it to be available in other drivers, along with DX12 and Metal.

[stqn]

20fps with consistent timing is better than 60fps with erratic timing

Not for me, no. 20 FPS is consistently unbearable, while minor stuttering around 60 FPS is just a bit annoying.

(I always try to get a constant 60 FPS setting in games though.)

[cl333r]

Not for me, no. 20 FPS is consistently unbearable, while minor stuttering around 60 FPS is just a bit annoying.

(I always try to get a constant 60 FPS setting in games though.)

Yeah, I generally agree. The misunderstanding though is that you said "minor" and the author obviously meant either "significant" or "bad" stuttering.

Minor stuttering -> 60 fps is better.
Significant stuttering -> not sure.
Bad stuttering -> 20 fps of smooth framerate is better.

[anth]

Not for me, no. 20 FPS is consistently unbearable, while minor stuttering around 60 FPS is just a bit annoying.

Watching the video or at least skimming through the slides might change your mind, but failing that consider this contrived example which is probably more extreme than anything in there ...

1. 60fps with a constant 16.7ms/frame.
2. 20fps with a constant 50ms/frame.
3. 60fps with 55 of those at 9ms/frame and 5 at 100ms/frame.

Clearly option 1 is best, but option 3 is worst despite having the same number of frames per second. Many of the frames the engine is pushing out won't even be displayed, at least not in full, on a 60Hz screen.

Basically framerate is an oversimplification, and the game engine needs to know the frametime so it can make adjustments to keep things smooth.

I'm surprised that this is what gets comments, rather than that Linux using Mesa can provide this data but that Windows and Mac can't.