vec3.transformMat4 performs w-division; vec2.transformMat4 does not

[ghost]

As pointed out here #279 (comment), vec4.transformMat4 doesn't do w-division, and the user is responsible for doing it:

gl-matrix/src/vec4.js

Lines 478 to 488 in 21b745f

	export function transformMat4(out, a, m) {
	let x = a[0],
	y = a[1],
	z = a[2],
	w = a[3];
	out[0] = m[0] * x + m[4] * y + m[8] * z + m[12] * w;
	out[1] = m[1] * x + m[5] * y + m[9] * z + m[13] * w;
	out[2] = m[2] * x + m[6] * y + m[10] * z + m[14] * w;
	out[3] = m[3] * x + m[7] * y + m[11] * z + m[15] * w;
	return out;
	}

For vec3.transformMat4 (assumes w=1), the W-division is done, presumably because the w-component isn't returned, so it's done because the user couldn't do it:

gl-matrix/src/vec3.js

Lines 505 to 515 in 21b745f

	export function transformMat4(out, a, m) {
	let x = a[0],
	y = a[1],
	z = a[2];
	let w = m[3] * x + m[7] * y + m[11] * z + m[15];
	w = w || 1.0;
	out[0] = (m[0] * x + m[4] * y + m[8] * z + m[12]) / w;
	out[1] = (m[1] * x + m[5] * y + m[9] * z + m[13]) / w;
	out[2] = (m[2] * x + m[6] * y + m[10] * z + m[14]) / w;
	return out;
	}

For vec2.transformMat4 (assumes z=0 and w=1), however, the w-division is not done. Unfortunately, the user can't do it either, because the w-component isn't returned (so the user must compute w themselves, which defeats the purpose):

gl-matrix/src/vec2.js

Lines 442 to 448 in 21b745f

	export function transformMat4(out, a, m) {
	let x = a[0];
	let y = a[1];
	out[0] = m[0] * x + m[4] * y + m[12];
	out[1] = m[1] * x + m[5] * y + m[13];
	return out;
	}

I'd like to see this fixed or a new function added for this purpose, but it's obviously a breaking change if this function was modified. It could also help to have a function to compute w (maybe a homogenous-dot-product already exists for this?), then the w division can be avoided.
A potential use-case for this can be found in maplibre (which would already benefit from the vec3 variant, but could be optimized further).