Editor Viewport Rendering Bug

Development Rendering
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1

For several engine version so far (4.3, 4.5 and 4.6), I have been getting some strange visual glitches in the main viewport of the editor, as well as in all 3D views in other editors.

I think the issue speaks for itself:

28303-editor_view.jpg
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As you can see, the entire viewport is heavily blurred, editor billboards are permanently rotated sideways, and everything appears to be “stretching” into the centre of the screen.

When PIE is used, it appears slightly different:

28304-pie_view.jpg
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While not stretched into the centre, it is clear that the objects are not rendering correctly. The polygons on the terrain that should be hidden are being rendered regardless, and the cube is not being rendered where it would hide the floor mesh. The heavy fogging is still present.

This issue occurs in all preview windows, such as new window and even standalone process. It also affects packaged builds of the affected projects.

As I stated before, this issue has occurred on 3 engine branches I have worked with. The issue seems to not immediately present itself when the new engine is used; rather it may take several weeks for months to present itself. For example, the issue did not present itself in 4.6.1 until today, meaning it has been working correctly on at least 2 projects until now.
However, once it appears for the first time, all projects using that particular branch are so far guaranteed to have the issue within around 2-3 start-ups of the editor.

Using the buffer visualiser, I noticed the GBuffer appears to be “inverted” where it should block an object; instead, it will draw what is behind that:

28305-gbuffer.png

If it helps, my computer’s specs are:
Intel i7-2860QM (2nd Gen) (2.5GHz);
NVIDIA GeForce GTX 580M 2GB;
16GB RAM;
NVIDIA Driver 335.23;

The issue makes it almost impossible to continue development on the affected projects and is extremely frustrating.
Any solution or possible explanation of this bug would be greatly appreciated.

Thanks,

2

Hi ,

When you encounter this in your projects is there anything that you’re aware of that causes the change?

Is this something that doesn’t replicate immediately in any new projects? If so, how long does it usually take before this starts to happen?

Do you have a simple test project that has this issue that you’d be willing to share and see if I can get the same results on my end? This can help narrow down if something may be going on hardware/driver vs Project.

Also, I see you’re using the Nvidia 335 drivers. Can you upgrade your drivers to the latest version of 347.25?

Last thing, Just as a test, can you delete your saved and intermediate folders and see if this possibly resolves the issue?

Thanks!

Tim

3

Tim,

I have tested some of the options you suggested, which unfortunately, did not help.
I updated my drivers just prior to your response to no avail, nor did deleting those folders help.

I also tested this further by moving the affected project to a copy of UE4 on a Mac. It presented a very similar issue, any differences most probably caused by it using OpenGL rather than DirectX. This leads me to believe that it may be project-specific rather than an issue with my PC.

As per your suggestion, I have packaged the affected project into a zip file. You may download it here:
https://www.dropbox.com/s/ye0wp5c2e6wletl/ue4_shader_bug.zip?dl=0

I attempted to cause the bug on a fresh project, but after around 20 minutes of trying, I stopped. I cannot find a specific trigger for this issue.
Thanks for the help,

4

Thank you, !

I was able to see the issue it’s causing. That is a very strange one! I’ve submitted a ticket with this project attached for an engineer to take a look at. The reference number is UE-9360.

I’m glad you’re able to work in any other projects without this one being an issue. I was able to migrate all the content to a new project that didn’t cause the issue.

You may be able to do that and see if it works as well.

Thank you for your report!

Tim

5

Just had this same issue today, along with nothing rendering in the proper order, here is a post of mine: https://answers.unrealengine.com/questions/288824/whole-projects-render-ordernormals-are-inccorect.html

6

I’ve actually resolved this issue (or at least my cause for it) a while ago. It was caused by setting the Near-Z value in the general project settings to 0. Resetting it to non-zero fixed the problem. Either way, this still a bug as the value shouldn’t be able to go as low as 0.

7

This issue is fixed by setting the Near-Z in the project settings to a non-zero value.

8

Oh thankyou, I did set that setting to 0 last night, I guess it didn’t take effect until this morning when I re-launched my project.

9

Thankyou Valax321, I had this issue too and had no idea what was causing it. I had set the near-Z to 0 and seen no effect, packaged a project, restarted the editor and found that both the build and in-editor view had the ‘inverted g-buffer’. Setting near-clip to non-zero fixed it after a restart.

Thanks again. Hopefully people google searching for “unreal engine rendering errors” or “Viewport flipped normals”, etc, will find this.