Question Detecting the edge of a projector via shader.

Hello, I'm trying to detect the edge of this cone (the angle may change) and I was wondering if there is a simple way to do it?

 

What kind of projector is this? This is the Shader Graph forum, which usually means you're using it for the URP or HDRP, but neither support perspective decal projections. So this makes me thing you're using the legacy projector component in the built in renderer, in which case you're more likely using a regular vertex fragment shader and not Shader Graph ... so I'm not sure if you posted here in error or if you've somehow gotten Shader Graph to work with the legacy projector.

If it's the later, you should already have your answer as that's the only way to keep the projector from rendering across the entire surface you're touching.

Or you're using a top down decal projector and the "cone" is defined by the texture being used as those decals don't have an "angle" to detect?