Ticket #3205: new_common_color_file.patch

gui/common/color.js

@@ +1 @@
+////////////////////////////////////////////////////////////////////////////////////////////////
+// some color functions previously used from lobby.js
+// now spread over lobby.js and gamesetup.js
+
+// Ensure `value` is between 0 and 1.
+function clampColorValue(value)
+{
+    return Math.abs(1 - Math.abs(value - 1));
+}
+
+function rgbToHsl(r, g, b)
+{
+    r /= 255;
+    g /= 255;
+    b /= 255;
+    var max = Math.max(r, g, b), min = Math.min(r, g, b);
+    var h, s, l = (max + min) / 2;
+
+    if (max == min)
+        h = s = 0; // achromatic
+    else
+    {
+        var 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];
+}
+
+function hslToRgb(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;
+    }
+
+    [h, s, l] = [h, s, l].map(clampColorValue);
+    var r, g, b;
+
+    if (s == 0)
+        r = g = b = l; // achromatic
+    else {
+        var q = l < 0.5 ? l * (1 + s) : l + s - l * s;
+        var 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, g, b].map(function (n) Math.round(n * 255));
+}
+
+