WebGLMultipleRenderTargets: Add new class.

[Mugen87]

Why

A new type of render target was added with mrdoob/three.js#16390.

What

Adds type declaration file for WebGLMultipleRenderTargets.

Checklist

• Added myself to contributors table
• Ready to be merged

[joshuaellis]

Thanks for the contribution! ⭐

[Mugen87]

Seems the linter reports an error. Do you have an idea what is going wrong?

[joshuaellis]

WebGLMultipleRenderTargets extends WebGLRenderTarget so TS expects the property texture to be the same type...

@Methuselah96 Do you have an ideas how we might resolve this? 🤔 I always find it odd that you can override methods but not properties.

Although @Mugen87, looking at the THREE code, wouldn't calling WebGLMultipleRenderTargets.setTexture fail because i'd either have to supply an array which would break:

texture.image = {
	width: this.width,
	height: this.height,
	depth: this.depth
};

see here.

Alternatively not passing an array of Textures, would break the WebGLMultipleRenderTargets?

[Mugen87]

It seems setTexture() should not be used in context of WebGLMultipleRenderTargets since it maintains multiple textures in a special way. If you call the method with a single texture, the code will crash.

[joshuaellis]

Yeah, so this afaik wouldn't be 'allowed' in typescript... So we may need to copy the class WebGLRenderTarget and remove certain bits as opposed to extending from... 🤔

void

[Mugen87]

Closing this PR. I'm afraid the mentioned problems exceed my TS knowledge^^. I hope somebody else can tackle this feature.

BTW: It was considered in mrdoob/three.js#16390 (comment) to not extend the class from WebGLRenderTarget. Maybe it's a good idea to highlight the typing issues at the three.js repo. Seems the class design could be cleaner if the inheritance is changed.