How can I Flip my Camera's display in the -Y axis?

Hiya all,

Looking for some examples or help as to how to wire up a BP Camera that simply flips the output of what it scenes in the -Y axis. ( like looking in a mirror )

My hack was to attempt to actually make a mirror material, but the performance hit was too much. I have to believe that there is a straightforward way to rewire the Screenspace to flop in the -Y.

Any advice in doing so would be greatly appreciated.

Thank you.

I doubt there is any way to do it. esp in blueprints.

I was looking into doing this myself recently and I read something about using blendables to achieve it, but I haven’t looked further into it. I ended up going with what you mentioned, the render texture flip because what I was working on wasn’t really performance-dependent. Hopefully that leads you down a research rabbit hole to your answer :slight_smile:

@Jared : Would you mind elaborating on what you did exactly!? My solution wasn’t elegant, and perhaps you have a more clever way of implementing the render texture flip, that I could try.

Well, I tried the blendable post method, and was able to get it 98% of the way there…

I basically followed this example: UE4 Controlling PostProcess Material Tutorial - But wired it up for my specific needs.
See here:

It works, but I’m getting a UV offset that I can’t account for. Seen here:

645a2436e628b471706652ae7a26a13d0b0cd853.jpeg

I’m investigating why It’s occurring… Any thoughts on it, again, would be appreciated!

thanks!

Well, my solution is a total Hack, I’m sure of it.
I never did explain why scaling from the ‘center’ creates an offset… but I just compensated for it… and It’s working. Like I said, it feels like a filthy solution, but it’s working.
I couldn’t find anyone who had successfully done it and posted how… so I’m hoping this thread will help those lost souls like myself, who don’t mind a bith of filth in their setup. :wink:

I’m eager for a Black Belt to get on and explain how to do it correctly, and why I was having the anomalies I was. But until then… I’m good.
Here is my final Post Process Material:

At the risk of spamming this thread… I came across a Bug? I have to imagine the offset I’m seeing is a bug in the ScaleUVsByCenter if I flip them completely. Because in theory, it should be 1:1. It’s not, apparently.

So then I compensated for it, no big deal. However, now it seems every time I load the level, the offset needs a different value. Ranging from -0.1 to -0.25. No rhyme or reason, and is unique and inconsistent every time.

So I’m guessing BUG. If anyone can prove me wrong, please do. Or if anyone can verify and help me report it, that too.

thanks.

Hi, I have found your issue. You need to be using the proper resolution.

wow thats amazyng… it totally worked for me. I am a architecture visualiter and i need to mirroring the whole apartment and i dont want to construcction a whole new level. One thing the “V ofsets” its “0” not “-0.1” thanks!

To flip the screen:

  • you need post process volume to spawn the level.
    image

  • Create one post process material

Set the Material Domain as Post Process instead of default one.

Insert SceneTexture and set its id as PostProcessInput0
image

Add the nodes as below:

  • Bind the pp material to pp volume by Details → PostProcessMaterial → + Element to choose the pp material.