Add function to find nearest color given an array of colors based on color difference using specified color spaces

[lulunac27a]

I want to add a function that finds the nearest color from an array of colors that are based on color difference using specified color spaces.

[facelessuser]

It's pretty easy to write one around the existing API, but I think it would get a lot of use if it was made part of the existing API, so I'm a +1 on this.

[lulunac27a]

The function is defined as:

Color.nearestColor(color, colorArray, colorSpace, weights)

color is the color to get the closest to that color in the array
colorArray is the list of colors to find the closest color
colorSpace is the color space method to get the closest color
weights are the weights for the color difference based on the color space selected

Example code:

const red = new Color("red");
const blue = new Color("blue");
const green = new Color("green");
const black = new Color("black");
Color.nearestColor("brown", [red, blue, green, black], "lab", [1, 1, 1]);

[LeaVerou]

Why use a color space for color difference (especially given many are not perceptually uniform) and not a deltaE method which was designed for this?

I’m not sure we need a method for this, but I would support having this a "recipe" in the docs that people could copy paste, or a plugin. It's basically:

function (color, colorArray, {deltaEMethod} = {}) {
	let minDeltaE = Infinity, ret;
	for (let c of colorArray) {
		let deltaE = deltaE(color, c, deltaEMethod);
		if (deltaE < minDeltaE) {
			minDeltaE = deltaE;
			ret = c;
		}
	}
	return ret;
}

[facelessuser]

I agree, I would be against using a space instead of requiring a specific delta E method. If you had a non-perceptual differencing approach that, for whatever reason, accepted a space and an option, I guess you could pass options to that method, but I wouldn't make specifying the space as part of the API for nearestColor or whatever it gets called.

[lulunac27a]

The code above is based on the Delta E methods, with the latest one is Delta E 2000.