Initial Commit

node_modules/color-space/hcg.js

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+/**
+ * @module color-space/hcg
+ */
+import rgb from './rgb.js';
+import hsl from './hsl.js';
+import hsv from './hsv.js';
+import hwb from './hwb.js';
+
+var hcg = {
+	name: 'hcg',
+	min: [0, 0, 0],
+	max: [360, 100, 100],
+	channel: ['hue', 'chroma', 'gray'],
+	alias: ['HCG', 'HSG'],
+
+	rgb: function (hcg) {
+		var h = hcg[0] / 360;
+		var c = hcg[1] / 100;
+		var g = hcg[2] / 100;
+		if (c === 0.0) {
+			return [g * 255, g * 255, g * 255];
+		}
+		var hi = (h % 1) * 6;
+		var v = (hi % 1);
+		var pure = [0, 0, 0];
+		var w = 1 - v;
+		switch (Math.floor(hi)) {
+			case 0:
+				pure[0] = 1; pure[1] = v; pure[2] = 0; break;
+			case 1:
+				pure[0] = w; pure[1] = 1; pure[2] = 0; break;
+			case 2:
+				pure[0] = 0; pure[1] = 1; pure[2] = v; break;
+			case 3:
+				pure[0] = 0; pure[1] = w; pure[2] = 1; break;
+			case 4:
+				pure[0] = v; pure[1] = 0; pure[2] = 1; break;
+			default:
+				pure[0] = 1; pure[1] = 0; pure[2] = w;
+		}
+		var mg = (1.0 - c) * g;
+		var rgb = [
+			(c * pure[0] + mg) * 255,
+			(c * pure[1] + mg) * 255,
+			(c * pure[2] + mg) * 255
+		];
+		return rgb;
+	},
+
+	hsl: function (hcg) {
+		var c = hcg[1] / 100;
+		var g = hcg[2] / 100;
+		var l = g * (1.0 - c) + 0.5 * c;
+		var s = 0;
+		if (l < 1.0 && l > 0.0) {
+			if (l < 0.5) {
+				s = c / (2 * l);
+			} else {
+				s = c / (2 * (1 - l));
+			}
+		}
+		return [hcg[0], s * 100, l * 100];
+	},
+
+	hsv: function (hcg) {
+		var c = hcg[1] / 100;
+		var g = hcg[2] / 100;
+		var v = c + g * (1.0 - c);
+		var res;
+		if (v > 0.0) {
+			var f = c / v;
+			res = [hcg[0], f * 100, v * 100];
+		} else {
+			res = [hcg[0], 0, v * 100];
+		}
+		return res;
+	},
+
+	hwb: function (hcg) {
+		var c = hcg[1] / 100;
+		var g = hcg[2] / 100;
+		var v = c + g * (1.0 - c);
+		return [hcg[0], (v - c) * 100, (1 - v) * 100];
+	}
+};
+
+export default (hcg);
+
+
+//append rgb
+rgb.hcg = function (rgb) {
+	var r = rgb[0] / 255;
+	var g = rgb[1] / 255;
+	var b = rgb[2] / 255;
+	var max = Math.max(Math.max(r, g), b);
+	var min = Math.min(Math.min(r, g), b);
+	var chroma = (max - min);
+	var grayscale;
+	var hue;
+	if (chroma < 1) {
+		grayscale = min / (1 - chroma);
+	} else {
+		grayscale = 0;
+	}
+	if (chroma > 0) {
+		if (max === r) {
+			hue = ((g - b) / chroma % 6);
+		} else
+			if (max === g) {
+				hue = 2 + (b - r) / chroma;
+			} else {
+				hue = 4 + (r - g) / chroma;
+			}
+		hue /= 6;
+		hue = (hue % 1);
+	} else {
+		hue = 0;
+	}
+	return [hue * 360, chroma * 100, grayscale * 100];
+};
+
+//extend hsl
+hsl.hcg = function (hsl) {
+	var s = hsl[1] / 100;
+	var l = hsl[2] / 100;
+	var c = 0;
+	if (l < 0.5) {
+		c = 2.0 * s * l;
+	} else {
+		c = 2.0 * s * (1.0 - l);
+	}
+	var res;
+	if (c < 1.0) {
+		var f = (l - 0.5 * c) / (1.0 - c);
+		res = [hsl[0], c * 100, f * 100];
+	} else {
+		res = [hsl[0], c * 100, 0];
+	}
+	return res;
+};
+
+//extend hsv
+hsv.hcg = function (hsv) {
+	var s = hsv[1] / 100;
+	var v = hsv[2] / 100;
+	var c = s * v;
+	var res;
+	if (c < 1.0) {
+		var f = (v - c) / (1 - c);
+		res = [hsv[0], c * 100, f * 100];
+	} else {
+		res = [hsv[0], c * 100, 0];
+	}
+	return res;
+}
+
+
+//extend hwb
+hwb.hcg = function (hwb) {
+	var w = hwb[1] / 100;
+	var b = hwb[2] / 100;
+	var v = 1 - b;
+	var c = v - w;
+	var g = 0;
+	if (c < 1) {
+		g = (v - c) / (1 - c);
+	}
+	return [hwb[0], c * 100, g * 100];
+}