Initial Commit

node_modules/color-space/lchab.js

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+/**
+ * Cylindrical LAB
+ *
+ * @module color-space/lchab
+ */
+import xyz from './xyz.js';
+import lab from './lab.js';
+
+
+//cylindrical lab
+var lchab = {
+	name: 'lchab',
+	min: [0, 0, 0],
+	max: [100, 100, 360],
+	channel: ['lightness', 'chroma', 'hue'],
+	alias: ['LCHab', 'cielch', 'LCH', 'HLC', 'LSH'],
+
+	xyz: function (arg) {
+		return lab.xyz(lchab.lab(arg));
+	},
+
+	lab: function (lch) {
+		var l = lch[0],
+			c = lch[1],
+			h = lch[2],
+			a, b, hr;
+
+		hr = h / 360 * 2 * Math.PI;
+		a = c * Math.cos(hr);
+		b = c * Math.sin(hr);
+		return [l, a, b];
+	}
+};
+
+
+//extend lab
+lab.lchab = function (lab) {
+	var l = lab[0],
+		a = lab[1],
+		b = lab[2],
+		hr, h, c;
+
+	hr = Math.atan2(b, a);
+	h = hr * 360 / 2 / Math.PI;
+	if (h < 0) {
+		h += 360;
+	}
+	c = Math.sqrt(a * a + b * b);
+	return [l, c, h];
+};
+
+xyz.lchab = function (arg) {
+	return lab.lchab(xyz.lab(arg));
+};
+
+
+export default (lchab);