Trick for Masking off an object using ARKit

May be obvious but took me a bit to realize. We wanted to have a character walk from behind a wall using ARKit. We can detect the plane but needed to mask off the character. I would normally use a Depth-only write in a pre-pass to occlude the objects.

I couldn’t figure out a way to do this in UE4 for opaque materials. I could change them to transparent and use a post past or a stencil mask but then the objects render wrong in the transparent layer. They have complex shaders.

Hack solution is to apply the same screen space camera material to the object I want to use as a mask. Works a charm.

Hey thanks for the tip! Could you provide a simple example screenshot of how to set that material up?

I just used the ARCameraColorCorrected material that was included with the ARKit sample from Github. It is a bit complicated shader but similar to just applying the ARKitCamera Texture with screen coordinates as in this tutorial.
The one included did some scaling of the texture to keep aspect ratio correct and color corrected from srgb to linear color.