Examples: Added webgpu_nodes_loader_materialx

[mrdoob]

Description

Trying to add the WebGPU version of webgl_nodes_loader_materialx.

@sunag I guess the WebGPURenderer path is still missing some things?

[LeviPesin]

The problem is that you use a GLSL version of MaterialX nodes (the official version), not a node (i.e. language-independent) version (there is not one yet). GLSL cannot work with WebGPU.

[mrdoob]

Oh! D'oh!

Hmm... We should be better at error messages though...

[sunag]

I was thinking of make a transpiler from GLSL to WGSL or ShaderNode. I think this would also save a lot of future work.
Does that make sense to you?

[mrdoob]

A on-the-fly transpiler or offline?

[sunag]

Both I imagined, although offline seems more appropriate for performance.

For API something like this:

const decoder = new GLSLDecoder();
const encoder = new WGSLEncoder();
//const encoder = new ShaderNodeEncoder();

const transpiler = new Transpiler( decoder, encoder );

const wgslCode = transpiler.parse( 'glsl source code' );

[mrdoob]

Sounds good to me!

[Hoodgail]

@sunag
I had it in my mind as well. I recently created a simple typescript to GLSL transpiler, but I'll explore how difficult it would be to create a simple GLSL to WGSL transpiler.

[LeviPesin]

I think a transpiler from GLSL to ShaderNode would be even better and more future-proof...

[Hoodgail]

@LeviPesin Explain why that would be better than simply glsl to wgsl

[LeviPesin]

Because ShaderNodes can be compiled to both GLSL and WGSL.

[Hoodgail]

Because ShaderNodes can be compiled to both GLSL and WGSL.

Ohh!? Didn't know, because I was about to give up, WGSL's syntax is so complex, I might as well learn rust if I'm gonna learn that