Search in
Sort by:

Question Status:

Search help

  • Simple searches use one or more words. Separate the words with spaces (cat dog) to search cat,dog or both. Separate the words with plus signs (cat +dog) to search for items that may contain cat but must contain dog.
  • You can further refine your search on the search results page, where you can search by keywords, author, topic. These can be combined with each other. Examples
    • cat dog --matches anything with cat,dog or both
    • cat +dog --searches for cat +dog where dog is a mandatory term
    • cat -dog -- searches for cat excluding any result containing dog
    • [cats] —will restrict your search to results with topic named "cats"
    • [cats] [dogs] —will restrict your search to results with both topics, "cats", and "dogs"

New forward rendering artifact when used with VR instanced stereo

This is probably a known issue internally but just in case it's not I have noticed weird darkened tiles for the right eye when attempting to used VR instanced stereo on the github master/promoted branches for the upcoming 4.14 release.

It's hard to see in the provided screenshot but it's pretty obvious when actually using an HMD. You have to compare the areas circled for each eye rendering to notice the difference. The left eye seems correct but the right eye has certain quad areas on the screen that are darker than they should be.


Product Version: UE Github Master branch
more ▼

asked Sep 25 '16 at 08:13 PM in Bug Reports

avatar image

414 32 96 63

avatar image Rudy Q ♦♦ STAFF Sep 26 '16 at 02:10 PM

Hello tmek,

I have a few questions for you that will help narrow down what issue it is that you are experiencing.

Quick questions:

  1. Can you reproduce this issue in a clean project?

  2. If so, could you provide a detailed list of steps to reproduce this issue on our end?

  3. Could you provide screen shots of any blueprints/settings that may be involved in this issue?

avatar image tmek Sep 26 '16 at 09:11 PM

Hi Rudy,

I was able to reproduce this fairly easily. If you have a stationary point or spot light and look at it from a distance as shown in this video. (look in the right eye view at the point light shading on and surrounding the UE4 mannequin)


I'm assuming the forward shading is using a tiled rendering technique. It seems that in this situation, for only the right eye, certain tiles are not including the point light's contribution to the scene.

Here are the steps to recreate:

  1. Create a new project based on third person template.

  2. turn on forward shading, stereo instancing and MSAA in project settings.

  3. select the "ThirdPersonCharacter" actor in the scene and disable auto possesion.

  4. open "ThirdPersonGameMode" blueprint and set default pawn to DefaultPawn. (#3 and #4 will allow us to fly around the level freely)

  5. put a stationary point light right next to or a spot light shining down on the mannequin.

  6. run in VR mode and fly out as shown in the video above.

The left eye seems to render correctly but the right eye gets these weird darker squares/tiles around the areas lit by stationary point or spot lights.

(I should also point out that I'm using an Oculus CV1 if that makes a difference.)

Here's a cropped comparison screenshot zoomed in. Again showing the right eye rendering has some squares or tiles not rendering a stationary light's (a spot light in this case) influence correctly.


(comments are locked)
10|2000 characters needed characters left
Viewable by all users

1 answer: sort voted first

Hello tmek,

After running a few tests and doing some digging I found that this is a known issue (UE-36114) that has been submitted 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

more ▼

answered Sep 27 '16 at 03:40 PM

avatar image

Rudy Q ♦♦ STAFF
47.2k 545 132 525

avatar image tmek Sep 29 '16 at 02:47 AM

Thanks Rudy :)

Is answerhub the place to provide feedback on issues in promoted or master builds or is there a more appropriate place to do that?

avatar image Rudy Q ♦♦ STAFF Sep 29 '16 at 12:58 PM

If you have issues when using the engine and you feel that you have encountered an issue, this is the place that you will want to go for assistance.

(comments are locked)
10|2000 characters needed characters left
Viewable by all users
Your answer
toggle preview:

Up to 5 attachments (including images) can be used with a maximum of 5.2 MB each and 5.2 MB total.

Follow this question

Once you sign in you will be able to subscribe for any updates here

Answers to this question