WebGPURenderer: MeshPhysicalNodeMaterial - Fix clearcoatRoughness

[sunag]

Description

Value limits and geometry-based roughness adjustments were not applied to clearcoatRoughness.

More perceptive in the red sphere.

[mrdoob]

The material seem to be matching WebGLRenderer now 👌

WebGPU	WebGL

But seems like the background is blurrier compared to master 🤔

WebGPU	WebGPU (master )

[sunag]

But seems like the background is blurrier compared to master 🤔

I think this is not related to this PR, I believe it is due to some PMREM update that the screenshot was not updated.

[mrdoob]

Yes, it's definitely unrelated to this PR. I just wanted to make sure we're aware.

It's easier to see comparing these examples:

https://raw.githack.com/mrdoob/three.js/dev/examples/webgl_loader_gltf.html
https://raw.githack.com/mrdoob/three.js/dev/examples/webgpu_loader_gltf.html

[sunag]

WebGLRenderer only uses PMREM if backgroundBlurriness is greater than zero, I added scene.backgroundBlurriness = 0.001; in webgl_loader_gltf and had the same result as in WebGPU. I will improve this in an update.