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+// Released under the MIT/X11 license
+// http://www.opensource.org/licenses/mit-license.php
+"use strict";
+// ============================================================================
+// Color management methods
+// originally from
+// http://www.mjijackson.com/2008/02\
+// /rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript
+var Color = exports.Color = function Color(r, g, b) {
+    this.Luminosity = 0.85;
+    this.Desaturated = 0.4;
+
+    if (r instanceof Array) {
+        this.r = r[0];
+        this.g = r[1];
+        this.b = r[2];
+    } else {
+        this.r = r;
+        this.g = g;
+        this.b = b;
+    }
+}
+
+Color.prototype.update = function(r, g, b) {
+    this.r = r;
+    this.g = g;
+    this.b = b;
+};
+
+Color.prototype.hs = function(nStr) {
+    if (Number(nStr) === 0) {
+        return "00";
+    } else if (nStr.length < 2) {
+        return "0" + nStr;
+    } else {
+        return nStr;
+    }
+};
+
+Color.prototype.toString = function() {
+    let rH = Number(this.r.toFixed()).toString(16);
+    let gH = Number(this.g.toFixed()).toString(16);
+    let bH = Number(this.b.toFixed()).toString(16);
+    return "#" + this.hs(rH) + this.hs(gH) + this.hs(bH);
+};
+
+/**
+ * Converts an RGB color value to HSL. Conversion formula adapted from
+ * http://en.wikipedia.org/wiki/HSL_color_space. Assumes r, g, and b are
+ * contained in the set [0, 255] and returns h, s, and l in the set [0, 1].4343
+ *
+ * @param Number r The red color value
+ * @param Number g The green color value
+ * @param Number b The blue color value
+ * @return Array The HSL representation
+ */
+Color.prototype.hsl = function() {
+    let r = this.r / 255;
+    let g = this.g / 255;
+    let b = this.b / 255;
+    let max = Math.max(r, g, b), min = Math.min(r, g, b);
+    let h, s, l = (max + min) / 2;
+
+    if (max === min) {
+        h = s = 0; // achromatic
+    } else {
+        let d = max - min;
+        s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
+        switch (max) {
+        case r:
+            h = (g - b) / d + (g < b ? 6 : 0);
+            break;
+        case g:
+            h = (b - r) / d + 2;
+            break;
+        case b:
+            h = (r - g) / d + 4;
+            break;
+        }
+        h /= 6;
+    }
+
+    return [ h, s, l ];
+};
+
+/**
+ * Converts an HSL color value to RGB. Conversion formula adapted from
+ * http://en.wikipedia.org/wiki/HSL_color_space. Assumes h, s, and l are
+ * contained in the set [0, 1] and returns r, g, and b in the set [0, 255].
+ *
+ * @param Number h The hue
+ * @param Number s The saturation
+ * @param Number l The lightness
+ * @return Array The RGB representation
+ */
+Color.prototype.hslToRgb = function(h, s, l) {
+    function hue2rgb(p, q, t) {
+        if (t < 0) {
+            t += 1;
+        }
+        if (t > 1) {
+            t -= 1;
+        }
+        if (t < 1 / 6) {
+            return p + (q - p) * 6 * t;
+        }
+        if (t < 1 / 2) {
+            return q;
+        }
+        if (t < 2 / 3) {
+            return p + (q - p) * (2 / 3 - t) * 6;
+        }
+        return p;
+    }
+
+    let r, g, b;
+
+    if (s === 0) {
+        r = g = b = l; // achromatic
+    } else {
+        let q = l < 0.5 ? l * (1 + s) : l + s - l * s;
+        let p = 2 * l - q;
+        r = hue2rgb(p, q, h + 1 / 3);
+        g = hue2rgb(p, q, h);
+        b = hue2rgb(p, q, h - 1 / 3);
+    }
+
+    return [ r * 255, g * 255, b * 255 ];
+};
+
+/**
+ * Converts an RGB color value to HSV. Conversion formula adapted from
+ * http://en.wikipedia.org/wiki/HSV_color_space. Assumes r, g, and b are
+ * contained in the set [0, 255] and returns h, s, and v in the set [0, 1].
+ *
+ * @param Number r The red color value
+ * @param Number g The green color value
+ * @param Number b The blue color value
+ * @return Array The HSV representation
+ */
+Color.prototype.hsv = function() {
+    let r = this.r / 255;
+    let g = this.g / 255;
+    let b = this.b / 255;
+    let max = Math.max(r, g, b), min = Math.min(r, g, b);
+    let h, s, v = max;
+
+    let d = max - min;
+    s = max === 0 ? 0 : d / max;
+
+    if (max === min) {
+        h = 0; // achromatic
+    } else {
+        switch (max) {
+        case r:
+            h = (g - b) / d + (g < b ? 6 : 0);
+            break;
+        case g:
+            h = (b - r) / d + 2;
+            break;
+        case b:
+            h = (r - g) / d + 4;
+            break;
+        }
+        h /= 6;
+    }
+
+    return [ h, s, v ];
+};
+
+/**
+ * Converts an HSV color value to RGB. Conversion formula adapted from
+ * http://en.wikipedia.org/wiki/HSV_color_space. Assumes h, s, and v are
+ * contained in the set [0, 1] and returns r, g, and b in the set [0, 255].
+ *
+ * @param Number h The hue
+ * @param Number s The saturation
+ * @param Number v The value
+ * @return Array The RGB representation
+ */
+Color.prototype.hsvToRgb = function(h, s, v) {
+    let r, g, b;
+
+    let i = Math.floor(h * 6);
+    let f = h * 6 - i;
+    let p = v * (1 - s);
+    let q = v * (1 - f * s);
+    let t = v * (1 - (1 - f) * s);
+
+    switch (i % 6) {
+    case 0:
+        r = v;
+        g = t;
+        b = p;
+        break;
+    case 1:
+        r = q;
+        g = v;
+        b = p;
+        break;
+    case 2:
+        r = p;
+        g = v;
+        b = t;
+        break;
+    case 3:
+        r = p;
+        g = q;
+        b = v;
+        break;
+    case 4:
+        r = t;
+        g = p;
+        b = v;
+        break;
+    case 5:
+        r = v;
+        g = p;
+        b = q;
+        break;
+    }
+
+    return [ r * 255, g * 255, b * 255 ];
+};
+
+/**
+ * Provide
+ */
+Color.prototype.lightColor = function() {
+    let hslArray = this.hsl();
+    let h = Number(hslArray[0]);
+    let s = Number(hslArray[1]) * this.Desaturated;
+    let l = this.Luminosity;
+    let desA = this.hslToRgb(h, s, l);
+    return new Color(desA[0], desA[1], desA[2]);
+};