Material: Make .vertexColors a boolean.

[Mugen87]

This PR makes Material.vertexColors to a boolean. However, it's still possible for backwards compatibility reasons to use the old style by assigning one of the constants THREE.NoColors, THREE.VertexColors and THREE.FaceColors.

More information: #14788 (comment)

[donmccurdy]

Agreed on this change!

Do you want the strict .vertexColors === true checks in this PR, though? Just looking for truthiness would be more backward-compatible.

[Mugen87]

Just looking for truthiness would be more backward-compatible.

Makes totally sense! I've changed Projector and SVGRenderer accordingly.

[donmccurdy]

Does Geometry + FaceColors do anything a this point? With the former deprecated I don't think we want to keep FaceColors in the Material API, but just want to know what to expect for the next release.

[Mugen87]

Does Geometry + FaceColors do anything a this point?

At least not in context of WebGLRenderer. It's just important where you define color values in Face3.

three.js/src/core/DirectGeometry.js

Lines 175 to 187 in 76d16bd

	var vertexColors = face.vertexColors;
	if ( vertexColors.length === 3 ) {
	this.colors.push( vertexColors[ 0 ], vertexColors[ 1 ], vertexColors[ 2 ] );
	} else {
	var color = face.color;
	this.colors.push( color, color, color );
	}

SVGRenderer and Projector were the last classes performing checks on THREE.FaceColors. However, both treat THREE.FaceColors and THREE.VertexColors equally since a while. They do not really support vertex colors because of missing color interpolation. They expect vertex color values to be equal for a single triangle.

[Mugen87]

TBH, I would remove Projector and SVGRenderer at some point. Especially since SVGLoader can be used now to render SVG files with WebGL.

[donmccurdy]

At least not in context of WebGLRenderer. It's just important where you define color values in Face3.

Ok, thanks!

[mrdoob]

Nice clean up!

[mrdoob]

TBH, I would remove Projector and SVGRenderer at some point. Especially since SVGLoader can be used now to render SVG files with WebGL.

Well, the idea of SVGRenderer is to produce SVGs, which I've seem people using for creating vector illustrations for books.

[Mugen87]

Well, the idea of SVGRenderer is to produce SVGs, which I've seem people using for creating vector illustrations for books.

Okay, that's of course a valid use case for the renderer.

[mrdoob]

Thanks!