PassNode: Provide viewport and scissor API.

[Mugen87]

Fixed #31387

Description

It is currently not possible to define a custom viewport and scissor box when using pass(). The PR introduces setViewport() and setScissor() for custom value definition.

So in #31387, the OP must use below code in the render loop:

const dim = 128;
const x = renderer.domElement.offsetWidth - dim;
const y = renderer.domElement.offsetHeight - dim;

mapPass.setViewport( x, y, dim, dim );
//  renderer.setViewport(x, y, dim, dim); // previously

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	338.37 78.95	338.37 78.95	+0 B +0 B
WebGPU	558.42 154.55	558.42 154.55	+0 B +0 B
WebGPU Nodes	557.34 154.34	557.34 154.34	+0 B +0 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	469.6 113.66	469.6 113.66	+0 B +0 B
WebGPU	634.09 171.59	634.09 171.59	+0 B +0 B
WebGPU Nodes	589.22 160.94	589.22 160.94	+0 B +0 B

[mrdoob]

Nit: taregt > target

[mrdoob]

How about just this._viewport = null;?
If it's null it just uses the renderer one.

[Mugen87]

I've fixed the typo and renamed the properties but the fallback to the renderer viewport and scissor needs a bit more though.

[mrdoob]

Thanks!

[mrdoob]

How about just this._scissor = null;?
If it's null it just uses the renderer one.