Error in UE 4.8.0 Preview 4 when HUD and VR Preview

Im using Oculus DK2 with oculus_runtime_sdk_0.6.0.0_win installed. When making a HUD element by using a “Widget Blueprint”, for example even a simple button, I get the following problem when playing in VR preview.

On the right side of the right eye and the bottom of the whole view there are flickering errors. When I remove the f.e. button it will look normal again and work well.

Hello NethOr,

I was able to produce this issue on our end. I have written up a report (UE-16673) and I have submitted it to the developers for further consideration. I will provide updates with any pertinent information as it becomes available. Thank you for your time and information.

Make it a great day

We are experiencing this issue. Is there any word on when a fix will be completed?

Hello AnthonyGlueck,

There is no current time frame in place for the resolution of this issue, however I will be sure to bump up the community interest in the report for this issue. Thank you for your interest.

Make it a great day

I dug into this locally and found a way to fix this. In SlateRHIRenderingPolicy.cpp at the end of FSlateRHIRenderingPolicy::DrawElements, I added the following to reset the scissor rectangle back to the default.

	RHICmdList.SetScissorRect(false, 0, 0, 0, 0); // Added this

	CurrentBufferIndex = (CurrentBufferIndex + 1) % SlateRHIConstants::NumBuffers;
}

It seemed like the scissor was getting set to a smaller size while rendering the UI element but was never set back to the full screen. This was causing the depth buffer to not get fully cleared which lead to the corruption on screen.

Hi Rudy,

are there any news on this VR render bug?
It seems to affect everyone using a widget-based HUD… and it’s also blocking the VR version of our game title.

It seems like “BrantFrench” has identified and sort of fixed the problem already - so maybe it’s not too much work to sort it out? It’s a big blocker for VR developement - it’s worth fixing. :slight_smile:

Thank you very much!

Hello Joachim,

I went ahead and double checked on this issue for you. It appears that the status for this issue has not yet been updated to fixed as of yet. However, I will be sure to bump up the community interest for this issue.

Make it a great day

This is a pretty big issue, makes UMG almost useless for VR.

Submit a pull request, collect your badge!

I am also experiencing this issue with a VR research project for ASU. If there is a workaround I could perform until this is upstreamed, I would greatly appreciate it!

Hello ,

Depending on your needs a viable solution may be to use 3D widgets instead of adding them to the screen. I hope that this information helps.

Link: https://docs.unrealengine.com/latest/INT/Engine/UMG/HowTo/Create3DWidgets/index.html

Make it a great day