TSL: Simplified Fn() layout

[sunag]

Closes: #28794

Description

Simplifies creation and layout and returns an error warning if the If statement is returning a value in an inline/non-layout function.

material.colorNode = Fn( ( [ uv ] ) => {

	If( uv.lessThan( 0.5 ), () => {

		return vec4( 1, 0, 0, 1 );

	} );

	return vec4( 0, 0, 1, 1 );

}, { uv: 'vec2', return: 'vec4' } )( uv()) );

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	336.08 78.29	336.08 78.29	+0 B +0 B
WebGPU	531.16 147.59	532.29 147.91	+1.13 kB +322 B
WebGPU Nodes	530.63 147.48	531.76 147.8	+1.13 kB +323 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	465.15 112.18	465.15 112.18	+0 B +0 B
WebGPU	602.86 163.57	604 163.91	+1.14 kB +341 B
WebGPU Nodes	557.9 153.01	559.03 153.36	+1.14 kB +352 B

[sunag]

@Mugen87 Creating an automatic layout will involve more extensive work, so we can recommend creating a simplified layout in just one line.