WebGPURenderer: Improve RenderObject grouping - WIP

[sunag]

Related issue: #30560 (comment), #30560 (comment), #26673 (comment)

Description

This is a WIP.

The basic idea is to group the RenderObject so that we can handle similar objects.

Today we have a lot of redundant calls between similar objects in the rendering call that could be resolved in just one Backend.draw().

• Improve RenderObject grouping

  • Add a key related to the object to separate properties relevant to shader creation, such as object.morphTargetInfluences and object.count for filterObjects, RenderObjects.get and RenderObject.getChainArray().
  • Remove the term RenderObject.instances and leave only RenderObject.objects
  • Implement the dispose logic

• Create shared buffer

  • Create an extended buffer class designed to couple multiple uniforms.
  • Integrate shared buffer initially for modelWorldMatrix.
  • The buffer node is not being shared properly when shared with other materials, causing the buffer to be updated more than once in the same render call. WebGPURenderer: Improve cache bindings from node uniforms #32244
  • buffer does not have an integrated updateRanges range, which can be a problem if used in conjunction with instances since InstanceNode does not distinguish it with an attribute. WebGPURenderer: Add update ranges for bindings #32248
    

    three.js/src/nodes/accessors/InstanceNode.js

    Lines 120 to 126 in 8173be8

    	// Both WebGPU and WebGL backends have UBO max limited to 64kb. Matrix count number bigger than 1000 ( 16 * 4 * 1000 = 64kb ) will fallback to attribute.
    	if ( count <= 1000 ) {
    	instanceMatrixNode = buffer( instanceMatrix.array, 'mat4', Math.max( count, 1 ) ).element( instanceIndex );
    	} else {

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	356.24 86.48	356.24 86.48	+0 B +0 B
WebGPU	613.34 172.13	614.47 172.52	+1.13 kB +385 B
WebGPU Nodes	611.95 171.88	613.08 172.27	+1.13 kB +391 B

🌳 Bundle size after tree-shaking

Minimal build including a renderer, camera, empty scene, and dependencies.

	Before	After	Diff
WebGL	488.02 121.25	488.02 121.25	+0 B +0 B
WebGPU	682.75 187.41	683.88 187.79	+1.13 kB +380 B
WebGPU Nodes	624.47 170.62	625.6 171	+1.13 kB +376 B