Should WebGLMultipleRenderTargets extend WebGLMultipleRenderTarget?

[joshuaellis]

Is your feature request related to a problem? Please describe.

Introduced here – #16390, WebGLMultipleRenderTargets extends WebGLMultipleRenderTarget which on the surface works, however when we came to create the .d.ts file – three-types/three-ts-types#85 we began to discuss how maybe this shouldn't be the case. Calling WebGLMultipleRenderTargets.setTexture would fail because you'd either have to supply an array which would break:

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

see:

three.js/src/renderers/WebGLRenderTarget.js

Line 46 in d39d829

texture.image = {

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

Describe the solution you'd like

Whilst I appreciate how helpful it is to extend a lot of the features already written in WebGLMultipleRenderTarget, maybe there should be a utility/base class that they both inherit from, this would reduce duplication (which is why we extend classes in the first place) and equally avoid the edge cases described above that will impact users.

Additional context

For anyone interested, the .d.ts file will probably just duplicate the properties and methods included in WebGLMultipleRenderTarget

[joshuaellis]

Would it be better if I mocked up a proposal in a PR? Or would we rather discuss the issue here first?

[Mugen87]

I guess it's easier to see the impact of a change with a PR.

[mbredif]

Does #22089 solves this issue ?

[Mugen87]

Since #23498 removes WebGLRenderTarget.setTexture(), there is no inconsistency with WebGLMultipleRenderTargets.setTexture() anymore. So the inheritance itself should not cause any (type) issues anymore.