Does anyone recognize this artifact?

[aminiallight@mastodon.gamedev.place]

Does anyone recognize this artifact? I'm storing the texture in multiple images to avoid exceeding max image dimensions and I'm getting this weird glitch at the tile boundaries

Even stranger, it isn't reflected in the UVs (second picture) or when reading the same image for both regions (third picture) and the sampler is set to nearest + clamp-to-edge

Boosts appreciated

#vulkan #glsl #gpu #graphics

[aeva@mastodon.gamedev.place]

@AminiAllight it's interesting that the cracks seem axially aligned to screen space. is the pixel shader just a straight read or are you doing anything fancy that might be sharing information between lanes?

[aeva@mastodon.gamedev.place]

@AminiAllight try setting the sampler to nearest and clamp-to-edge, and doing just a straight read without anything fancy, no derivatives etc and see if the problem still shows up

[lisyarus@mastodon.gamedev.place]

@AminiAllight Is this a whole mesh or is it two separate meshes? If it's the former and you're selecting the image in the shader, the following can happen: a pixel selects one image, but it's neighbour selects another, and they can't decide on the appropriate mipmap level (which is computed based on uv differences in neighbouring pixels). Though in that case I'd expect 2x2-pixel-sized artifacts, while yours seem to be in some larger pixel tiles.

[lisyarus@mastodon.gamedev.place]

@AminiAllight Anyway, to rule this out, sample both textures first, and only then select one of the read values based on whatever condition you have.

[aminiallight@mastodon.gamedev.place]

@aeva I believe it's a straight read? The shader in question is: https://gitlab.com/amini-allight/lambdamod/-/blob/master/src/shaders/lit_textured_fragment.glsl