MIDI.js/js/Color/SpaceW3.js

/* 
	----------------------------------------------------
	Color Space : 1.2 : 2012.11.06
	----------------------------------------------------
	https://github.com/mudcube/Color.Space.js
	----------------------------------------------------
	RGBA <-> HSLA  <-> W3
	RGBA <-> HSVA
	RGBA <-> CMY   <-> CMYK
	RGBA <-> HEX24 <-> W3
	RGBA <-> HEX32
	RGBA <-> W3
	----------------------------------------------------
	Examples
	----------------------------------------------------
	Color.Space(0x99ff0000, "HEX32>RGBA>HSLA>W3"); // outputs "hsla(60,100%,17%,0.6)"
	Color.Space(0xFF0000, "HEX24>RGB>HSL"); // convert hex24 to HSL object.
	----------------------------------------------------
	W3 values
	----------------------------------------------------
	rgb(255,0,0)
	rgba(255,0,0,1)
	rgb(100%,0%,0%)
	rgba(100%,0%,0%,1)
	hsl(120, 100%, 50%)
	hsla(120, 100%, 50%, 1)
	#000000
*/

if (typeof(Color) === "undefined") var Color = {};
if (typeof(Color.Space) === "undefined") Color.Space = {};

(function () { "use strict";

var useEval = false; // caches functions for quicker access.

var functions = {
	// holds generated cached conversion functions.
};

var shortcuts = {
	"HEX24>HSL": "HEX24>RGB>HSL",
	"HEX32>HSLA": "HEX32>RGBA>HSLA",
	"HEX24>CMYK": "HEX24>RGB>CMY>CMYK",
	"RGB>CMYK": "RGB>CMY>CMYK"
};

var root = Color.Space = function(color, route) {
	if (shortcuts[route]) { // shortcut available
		route = shortcuts[route];
	}
	var r = route.split(">");
	// check whether color is an [], if so, convert to {}
	if (typeof(color) === "object" && color[0] >= 0) { // array
		var type = r[0];
		var tmp = {};
		for(var i = 0; i < type.length; i ++) {
			var str = type.substr(i, 1);
			tmp[str] = color[i];
		}
		color = tmp;
	}
	if (functions[route]) { // cached function available
		return functions[route](color);
	}
	var f = "color";
	for (var pos = 1, key = r[0]; pos < r.length; pos ++) {
		if (pos > 1) { // recycle previous
			key = key.substr(key.indexOf("_") + 1);
		}
		key += (pos === 0 ? "" : "_") + r[pos];
		color = root[key](color);
		if (useEval) {
			f = "Color.Space."+key+"("+f+")";
		}
	}	
	if (useEval) {
		functions[route] = eval("(function(color) { return "+f+" })");
	}
	return color;
};

// W3C - RGB + RGBA

root.RGB_W3 = function(o) { 
	return "rgb(" + (o.R >> 0) + "," + (o.G >> 0) + "," + (o.B >> 0) + ")"; 
};

root.RGBA_W3 = function(o) { 
	var alpha = typeof(o.A) === "number" ? o.A / 255 : 1;
	return "rgba(" + (o.R >> 0) + "," + (o.G >> 0) + "," + (o.B >> 0) + "," + alpha + ")"; 
};

root.W3_RGB = function(o) {
	var o = o.substr(4, o.length - 5).split(",");
	return {
		R: parseInt(o[0]),
		G: parseInt(o[1]),
		B: parseInt(o[2])
	}
};

root.W3_RGBA = function(o) {
	var o = o.substr(5, o.length - 6).split(",");
	return {
		R: parseInt(o[0]),
		G: parseInt(o[1]),
		B: parseInt(o[2]),
		A: parseFloat(o[3]) * 255
	}
};

// W3C - HSL + HSLA

root.HSL_W3 = function(o) {
	return "hsl(" + ((o.H + 0.5) >> 0) + "," + ((o.S + 0.5) >> 0) + "%," + ((o.L + 0.5) >> 0) + "%)"; 
};

root.HSLA_W3 = function(o) {
	var alpha = typeof(o.A) === "number" ? o.A / 255 : 1;
	return "hsla(" + ((o.H + 0.5) >> 0) + "," + ((o.S + 0.5) >> 0) + "%," + ((o.L + 0.5) >> 0) + "%," + alpha + ")"; 
};

root.W3_HSL = function(o) {
	var o = o.substr(4, o.length - 5).split(",");
	return {
		H: parseInt(o[0]),
		S: parseInt(o[1]),
		L: parseInt(o[2])
	}
};

root.W3_HSLA = function(o) {
	var o = o.substr(5, o.length - 6).split(",");
	return {
		H: parseInt(o[0]),
		S: parseInt(o[1]),
		L: parseInt(o[2]),
		A: parseFloat(o[3]) * 255
	}
};

// W3 HEX = "FFFFFF" | "FFFFFFFF"

root.W3_HEX = 
root.W3_HEX24 = function (o) {
	if (o.substr(0, 1) === "#") o = o.substr(1);
	if (o.length === 3) o = o[0] + o[0] + o[1] + o[1] + o[2] + o[2];
	return parseInt("0x" + o);
};

root.W3_HEX32 = function (o) {
	if (o.substr(0, 1) === "#") o = o.substr(1);
	if (o.length === 6) {
		return parseInt("0xFF" + o);
	} else {
		return parseInt("0x" + o);
	}
};

// HEX = 0x000000 -> 0xFFFFFF

root.HEX_W3 =
root.HEX24_W3 = function (o, maxLength) {
	if (!maxLength) maxLength = 6;
	if (!o) o = 0;
	var z = o.toString(16);
	// when string is lesser than maxLength
	var n = z.length;
	while (n < maxLength) {
		z = "0" + z;
		n++;
	}
	// when string is greater than maxLength
	var n = z.length;
	while (n > maxLength) {
		z = z.substr(1);
		n--;
	}
	return "#" + z;
};

root.HEX32_W3 = function(o) {
	return root.HEX_W3(o, 8);
};

root.HEX_RGB =
root.HEX24_RGB = function (o) {
	return {
		R: (o >> 16),
		G: (o >> 8) & 0xFF,
		B: o & 0xFF
	};
};

// HEX32 = 0x00000000 -> 0xFFFFFFFF

root.HEX32_RGBA = function (o) {
	return {
		R: o >>> 16 & 0xFF,
		G: o >>> 8 & 0xFF,
		B: o & 0xFF,
		A: o >>> 24
	};
};

// RGBA = R: Red / G: Green / B: Blue / A: Alpha

root.RGBA_HEX32 = function (o) {
	return (o.A << 24 | o.R << 16 | o.G << 8 | o.B) >>> 0;
};

// RGB = R: Red / G: Green / B: Blue

root.RGB_HEX24 =
root.RGB_HEX = function (o) {
	if (o.R < 0) o.R = 0;
	if (o.G < 0) o.G = 0;
	if (o.B < 0) o.B = 0;
	if (o.R > 255) o.R = 255;
	if (o.G > 255) o.G = 255;
	if (o.B > 255) o.B = 255;
	return o.R << 16 | o.G << 8 | o.B;
};

root.RGB_CMY = function (o) {
	return {
		C: 1 - (o.R / 255),
		M: 1 - (o.G / 255),
		Y: 1 - (o.B / 255)
	};
};

root.RGBA_HSLA =
root.RGB_HSL = function (o) { // RGB from 0 to 1
	var _R = o.R / 255,
		_G = o.G / 255,
		_B = o.B / 255,
		min = Math.min(_R, _G, _B),
		max = Math.max(_R, _G, _B),
		D = max - min,
		H,
		S,
		L = (max + min) / 2;
	if (D === 0) { // No chroma
		H = 0;
		S = 0;
	} else { // Chromatic data
		if (L < 0.5) S = D / (max + min);
		else S = D / (2 - max - min);
		var DR = (((max - _R) / 6) + (D / 2)) / D;
		var DG = (((max - _G) / 6) + (D / 2)) / D;
		var DB = (((max - _B) / 6) + (D / 2)) / D;
		if (_R === max) H = DB - DG;
		else if (_G === max) H = (1 / 3) + DR - DB;
		else if (_B === max) H = (2 / 3) + DG - DR;
		if (H < 0) H += 1;
		if (H > 1) H -= 1;
	}
	return {
		H: H * 360,
		S: S * 100,
		L: L * 100,
		A: o.A
	};
};

root.RGBA_HSVA =
root.RGB_HSV = function (o) { //- RGB from 0 to 255
	var _R = o.R / 255,
		_G = o.G / 255,
		_B = o.B / 255,
		min = Math.min(_R, _G, _B),
		max = Math.max(_R, _G, _B),
		D = max - min,
		H, 
		S,
		V = max;
	if (D === 0) { // No chroma
		H = 0;
		S = 0;
	} else { // Chromatic data
		S = D / max;
		var DR = (((max - _R) / 6) + (D / 2)) / D;
		var DG = (((max - _G) / 6) + (D / 2)) / D;
		var DB = (((max - _B) / 6) + (D / 2)) / D;
		if (_R === max) H = DB - DG;
		else if (_G === max) H = (1 / 3) + DR - DB;
		else if (_B === max) H = (2 / 3) + DG - DR;
		if (H < 0) H += 1;
		if (H > 1) H -= 1;
	}
	return {
		H: H * 360,
		S: S * 100,
		V: V * 100,
		A: o.A
	};
};

// CMY = C: Cyan / M: Magenta / Y: Yellow

root.CMY_RGB = function (o) {
	return {
		R: Math.max(0, (1 - o.C) * 255),
		G: Math.max(0, (1 - o.M) * 255),
		B: Math.max(0, (1 - o.Y) * 255)
	};
};

root.CMY_CMYK = function (o) {
	var C = o.C;
	var M = o.M;
	var Y = o.Y;
	var K = Math.min(Y, Math.min(M, Math.min(C, 1)));
	C = Math.round((C - K) / (1 - K) * 100);
	M = Math.round((M - K) / (1 - K) * 100);
	Y = Math.round((Y - K) / (1 - K) * 100);
	K = Math.round(K * 100);
	return {
		C: C,
		M: M,
		Y: Y,
		K: K
	};
};

// CMYK = C: Cyan / M: Magenta / Y: Yellow / K: Key (black)

root.CMYK_CMY = function (o) {
	return {
		C: (o.C * (1 - o.K) + o.K),
		M: (o.M * (1 - o.K) + o.K),
		Y: (o.Y * (1 - o.K) + o.K)
	};
};

// HSL (1978) = H: Hue / S: Saturation / L: Lightess
// en.wikipedia.org/wiki/HSL_and_HSV

root.HSLA_RGBA =
root.HSL_RGB = function (o) {
	var H = o.H / 360;
	var S = o.S / 100;
	var L = o.L / 100;
	var R, G, B;
	var temp1, temp2, temp3;
	if (S === 0) {
		R = G = B = L;
	} else {
		if (L < 0.5) temp2 = L * (1 + S);
		else temp2 = (L + S) - (S * L);
		temp1 = 2 * L - temp2;
		// calculate red
		temp3 = H + (1 / 3);
		if (temp3 < 0) temp3 += 1;
		if (temp3 > 1) temp3 -= 1;
		if ((6 * temp3) < 1) R = temp1 + (temp2 - temp1) * 6 * temp3;
		else if ((2 * temp3) < 1) R = temp2;
		else if ((3 * temp3) < 2) R = temp1 + (temp2 - temp1) * ((2 / 3) - temp3) * 6;
		else R = temp1;
		// calculate green
		temp3 = H;
		if (temp3 < 0) temp3 += 1;
		if (temp3 > 1) temp3 -= 1;
		if ((6 * temp3) < 1) G = temp1 + (temp2 - temp1) * 6 * temp3;
		else if ((2 * temp3) < 1) G = temp2;
		else if ((3 * temp3) < 2) G = temp1 + (temp2 - temp1) * ((2 / 3) - temp3) * 6;
		else G = temp1;
		// calculate blue
		temp3 = H - (1 / 3);
		if (temp3 < 0) temp3 += 1;
		if (temp3 > 1) temp3 -= 1;
		if ((6 * temp3) < 1) B = temp1 + (temp2 - temp1) * 6 * temp3;
		else if ((2 * temp3) < 1) B = temp2;
		else if ((3 * temp3) < 2) B = temp1 + (temp2 - temp1) * ((2 / 3) - temp3) * 6;
		else B = temp1;
	}
	return {
		R: R * 255,
		G: G * 255,
		B: B * 255,
		A: o.A
	};
};

// HSV (1978) = H: Hue / S: Saturation / V: Value
// en.wikipedia.org/wiki/HSL_and_HSV

root.HSVA_RGBA = 
root.HSV_RGB = function (o) {
	var H = o.H / 360;
	var S = o.S / 100;
	var V = o.V / 100;
	var R, G, B, D, A, C;
	if (S === 0) {
		R = G = B = Math.round(V * 255);
	} else {
		if (H >= 1) H = 0;
		H = 6 * H;
		D = H - Math.floor(H);
		A = Math.round(255 * V * (1 - S));
		B = Math.round(255 * V * (1 - (S * D)));
		C = Math.round(255 * V * (1 - (S * (1 - D))));
		V = Math.round(255 * V);
		switch (Math.floor(H)) {
			case 0:
				R = V;
				G = C;
				B = A;
				break;
			case 1:
				R = B;
				G = V;
				B = A;
				break;
			case 2:
				R = A;
				G = V;
				B = C;
				break;
			case 3:
				R = A;
				G = B;
				B = V;
				break;
			case 4:
				R = C;
				G = A;
				B = V;
				break;
			case 5:
				R = V;
				G = A;
				B = B;
				break;
		}
	}
	return {
		R: R,
		G: G,
		B: B,
		A: o.A
	};
};

})();