Update UTextureRenderTarget2D from CPU data

Development Rendering
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1

I am looking for a way to update a UTextureRenderTarget with content from the CPU.

Since its Resource member is a standard FTextureResource, I thought I would be able to update this simply by using UpdateTextureRegions the same way it is possible with normal UTexture2D instances, as demonstrated here: A new, community-hosted Unreal Engine Wiki - Announcements - Unreal Engine Forums . However, doing this crashes the engine inside the RHIUpdateTextureRegions call…

Currently, my actor has a property like that:

UPROPERTY(BlueprintReadWrite, EditAnywhere)
	UTextureRenderTarget2D* RTVideoTexture;

I created a RenderTarget2D asset in the editor and assigned it to this property of my actor instance through the editor.

In my actor, when I have new image data, I just use the UpdateTextureRegions from the above link to update the texture (modified so the function takes an FTextureResource). This works perfectly when “just” using UTexture2D instead of UTextureRenderTarget2D… I made sure the Render Target has the right size and pixel format in the editor, yet it still keeps crashing. I also tried something along the lines of

if (!RTVideoTexture) {
	RTVideoTexture = NewObject<UTextureRenderTarget2D>();
}

RTVideoTexture->InitCustomFormat(VideoSize.X, VideoSize.Y, EPixelFormat::PF_B8G8R8A8, true);
RTVideoTexture->UpdateResource();
RTVideoTexture->UpdateResourceImmediate(false);

before updating/using the texture, still unsuccessfully…

Background:
I want to be able to define the texture that gets written to through the editor, as this texture gets used by several other actors/materials. If I would create a UTexture2D dynamically, this would require complicated blueprint/c++ setups to “publish” this dynamic texture to all the actors that use it. Using a RenderTarget asset would allow me to simply assign the RT asset to all objects in the editor, with no further blueprint magic…

Is there any way to do this?

2

Update: The approach of using practically the same code as in the UpdateTextureRegions() method works fine for Render Targets as well.
It turns out that the whole problem was just a stupid copy-paste mistake: When updating the code from UpdateTextureRegions to use Render Targets, I simply forgot to change the type FTexture2DResource to FTextureRenderTarget2DResource and since it was using old c-style casts it would not give me a proper exception there.
Then you can use it just fine as described in other places for updating “normal” Texture2D objects. However, be aware that RenderTargets only support a subset of the available pixel formats.