@lisyarus @AminiAllight Does it go away if you use textureLod() and specify a constant mip value (i.e. 0)?

If so, and if all of your tiles are the same resolution, you could use textureQueryLod() on a constant texture (maybe just the first one in the texture array) to compute the correct mip value.

If not, then you'll need to sample all of the possible textures and select which is the correct one afterward (as @lisyarus previously suggested).

@lisyarus @AminiAllight I think it might be this.

Looking at the code you linked elsewhere, I think you might be running into undefined behavior caused by divergence in your shader because the image you're sampling can vary within a given screen quad (not mesh).