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PDADAPTIVE can get stuck at low frame rate and flicker.
Using UE4.14.3, I'm seeing an issue where with HMD PDADAPTIVE ON, and there has been a high render requirment, the frame rate is locked to 45hz rather than 90hz, the PD range has the capacity to bring the frame rate back, but it doesn't. If I then set hmd pd to say 0.5, this appears to reset the system, allowing 90hz and then pd automatically increases as you would expect.
Additionally when frame rate is low I will see flicker in one eye (right), so for example if I force a high PD to reduce frame rate then set something more rational, I will see flicker until frame rate is restored, but in the case above where frame rate fails to be restored, naturally the flicker persists.
I see the flicker issue on nvidia GFX cards (980), but have not seen on AMD, while I have seen the frame rate failing to be restored by PDADAPTIVE on both.
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- Is there a solution or work around?
I've attached a UE4.14.3 project that hopefully can demonstrate the issue your end. You will be able to try increasing load via PD and AA from key presses, you should hopefully find scenarios where frame rate is held low, and will exhibit flicker on NVIDIA cards (980 tested) - I just posted a related issue here: https://forums.oculus.com/developer/discussion/51299/issues-with-adaptivegpuperformancescale#latest
I'm not getting any flickering, but it does lock you into ASW. I found three signficant flaws with PDAdapative. Was able to fix two of them, but not the third.
1) AdaptiveGpuPerformanceScale is missing the sqrt() as done in the SDK sample
2) The pixel density multiplication is applied twice when AdaptiveGpuPerformanceScale != 1. This is an issue with the bNeedsUpdate flag
3) AdapativeGpuPerformanceScale gives back values that are too high.
