Global: Avoid usage of RGBFormat.

[Mugen87]

Related issue: -

Description

Avoids the usage of RGBFormat whenever possible in the docs and editor.

[mrdoob]

Thanks!

[Mugen87]

The following section is the last usage of THREE.RGBFormat.

three.js/src/renderers/webxr/WebXRManager.js

Lines 319 to 329 in e2aec1b

	newRenderTarget = new WebGLRenderTarget(
	glProjLayer.textureWidth,
	glProjLayer.textureHeight,
	{
	format: attributes.alpha ? RGBAFormat : RGBFormat,
	type: UnsignedByteType,
	depthTexture: new DepthTexture( glProjLayer.textureWidth, glProjLayer.textureHeight, depthType, undefined, undefined, undefined, undefined, undefined, undefined, depthFormat ),
	stencilBuffer: attributes.stencil,
	ignoreDepth: glProjLayer.ignoreDepthValues,
	encoding: renderer.outputEncoding
	} );

@cabanier Is it possible to always create the render target in the RGBA format? Or would this require that all XR scenes set the WebGL context parameter alpha to true?

[cabanier]

@cabanier Is it possible to always create the render target in the RGBA format? Or would this require that all XR scenes set the WebGL context parameter alpha to true?

No, that is unrelated. I'd love if we just removed plain RGB. This format is so slow that we actually allocate it as RGBA under the hood and then pretend it doesn't have an alpha channel. I'm sure this has unintended side effects.