I applied a basic patch to replace WebGLRenderer with WebGPURenderer, the simple patch seen here . This causes one of my test cases to have really bad shadow acne, plus the lighting looks different. In either case, I’m using physically correct lights (gonna be nice cleanup when legacy mode is remove…

Not really sure if this might help with your issue but if you check this topic there is a standalone GLTF Viewer, attached at the bottom of the post and currently using r168, which will allow you to manipulate any parts of the code so you can see the outcome. In this viewer I went about replacing a…

Thanks @GitHubDragonFly . The example above is only using a couple spheres and lights. Fairly basic. Actually this demo should be easy to recreate with plain Three.

The renderer is still WIP so there are open issues like this one. With WebGPURenderer we have switched to depth textures for representing shadow maps (so the renderer does not use MeshDepthMaterial anymore). However, this new approach leads to more visible shadow acne which must be handled manually…

[image] Mugen87: depth textures for representing shadow maps (so the renderer does not use MeshDepthMaterial anymore I imagine that the texture could somehow be made the same resolution as what WebGLRenderer would have been doing with MeshDepthMaterial. Is that the issue? Or is there more to …

I experienced issues a long time ago that might be related… Some of the shaders in threejs use(d) different methods to transform vertices, and thus get slightly different results. i.e.: gl_Position = modelMatrix * viewMatrix * projectionMatrix; vs: gl_Position = modelViewMatrix * projecti…

I meant about shadow acne. i.e. the symptoms described sound similar to something I’ve seen before where different functions were used to transform vertices, yielding slightly different results, so shadowmap depths don’t exactly match what the regular shaders output.

Ah, gotcha. In this case, it seems that the shadow acne pieces are huge compared to any possible imprecision in the sphere surface, but who knows that’s just what I see visually. For example, in the above screenshot, the acne bands (which are like bands of individual shadow triangles) seem to be ori…

[WebGPU migration] intense shadow acne, and different lighting, after swapping from WebGLRenderer to WebGPURenderer

Questions

trusktr September 12, 2024, 3:24pm 7

@manthrax Is this about the shadow acne? Or did you mean to reply to my other issue about the transforms?

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[WebGPU migration] intense shadow acne, and different lighting, after swapping from WebGLRenderer to WebGPURenderer

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