Material with RenderTarget2D is buggy in fullscreen

I have this material:

In windowed mode the material looks like this:

But in fullscreen the material looks like this:

You see there is a big black area and the texture itself is smaller. I can switch between fullscreen and windowed with alt+enter and the material switches between working and buggy.

This bug only happens if a RenderTarget2D is used as texture in the material, if I use a regular Texture2D I don’t get the bug.

Hey Alcatraz,

Would you provide me with the engine version you are reporting this issue on, as well as some simple steps you took to get to this point?

Thank you,

Version is 4.7.5 on Windows.


  1. Create a RenderTarget2D
  2. Connect something to fill it (I use SceneCapture2D)
  3. Right click on the RenderTarget2D and make a material out of it
  4. Create a UMG widget with an image widget which draws the material and add the UMG widget to the viewport.
  5. Then run the game in standalone and toggle between windowed and fullscreen with alt-enter.

Hey Alcatraz,

Thank you for the clear reproducible steps. I was able to confirm what you are seeing in the engine version you are using. I went to test this in our main branch and it appears a fix was implemented which resolves the issue. I attempted to hunt through our bug reports to find a potential candidate for this issue, but was unable to find one that related exactly. There were a good few fixes implemented in our main build which dealt with SceneCapture2d and RenderTarget components rendering in fullscreen standalone however, so I can assume one of these fixes handled your issue as well.

If you would like to see the fix a bit earlier, you can go onto GitHub later today, which should be updated tomorrow at the latest, and grab our latest promoted build. Keep in mind promoted builds are not our release builds so they can be unstable, but the fix should be integrated within that engine build. We will begin releasing preview builds to the public for 4.8 in the upcoming weeks, so if you do not mind waiting a little for this bug fix to be released to a binary version that will be upcoming in the future.


Hey Andrew, I still experience the issue in the 4.8P1.

Yes, the previews will continue to have more fixes included before the full release of 4.8. Please remain patient while we get through the preview process and integrate bugs found in our previous versions which we tagged to have fixed in 4.8.

Oh, I thought you have all the fixes in the first preview and will only add the new fixes which are created now to the next preview…

The bug is still not fixed in Preview 3… Just wanted to mention :slight_smile:

Thank you for letting us know.

It’s not even in Preview 4… Are you really sure this will be fixed in 4.8?

Hey Alcatraz,

I just tested the issue again and was not able to see the clipping. Do me a favor and within your Widget Blueprint set the anchor for your image to the center and be sure it is exactly centered. Instead of using alt+enter to go fullscreen, use the ‘r.setRes ResolutionxResolutionf’ console command.

Image Widget Set Up

Then I simply followed the same steps for creating the widget and adding it to my viewport upon ‘Event Begin Play’. I played in standalone mode and did not see the issue.

Here is the fullscreen version when using the alt+enter versus using the console command.

Alt+Enter Option

Console Command Option

Obviously there is a visual difference in the way each fullscreen option behaves, but using the set resolution command is the definitive way to get your project/game to render in fullscreen.

If you have any questions about what I have done here or about my process just let me know.

Thank you,

Hi Andrew,

I know that the bug does not occur with using the console command r.setRes, but it does occur with using alt+enter and thats the important thing. Using the console command is a working workaround, but alt+enter also have to work.

You at Epic think this is a really major bug, the marketplace team even said I can only sell my Minimap (which uses a RenderTarget) on the Marketplace after this bug will be fixed in 4.8. Because if a bug occurs after pressing alt+enter it’s not good enough for being sold on the marketplace. I found a way to workaround it, but this workaround is ugly and I would like to remove it as soon as possible.

Do this mean it will not be fixed in 4,8??

Anyway, thanks for even answering on a Saturday, I really appreciate this :slight_smile:

Hey ,

I understand your concern and will be sure to communicate it forward. I have updated the bug report with the new information as far as the differences between setting the fullscreen mode and its overall outcome. Thank you for remaining patient while this bug was being tested. Here is the official bug report for the issue UE-16411.

When I receive an update pertaining to the fix being implemented into a build, I will let you know. As I am sure you also know you can find these updates in our Release Notes on our Forums whenever we release a public build as well.


Thanks! This probably means you won’t be able to fix this in 4.8?

It might make it in 4.8, but I cannot promise anything. This issue seems to be rooted in Slate which might take a bit longer to locate the actual problem and implement a fix.

Just to add to this; I need this to not happen during Alt + Enter too; Unless there is a way to disable Alt + Enter?

This issue has been marked to be fixed in an upcoming release. I cannot provide anymore details at this time, but we ask that you remain patient while we continue to implement bug fixes and release new versions for improvement.

I am on latest release and here is my pictures of similar bug Why does my mini-map zoom in when i go to full screen? - Programming & Scripting - Unreal Engine Forums

Hi. i am running into this problem. what is your workaround out of curiosity? i need it working asap