The Color.HSVToRGB function has been rewritten to use the HSL and HSV formula from Wikipedia, giving much better results. Fix phaserjs#5089

Author: photonstorm

src/display/color/HSVToRGB.js

@@ -7,10 +7,32 @@
 var GetColor = require('./GetColor');
 
 /**
- * Converts an HSV (hue, saturation and value) color value to RGB.
- * Conversion formula from http://en.wikipedia.org/wiki/HSL_color_space.
+ * RGB space conversion.
+ *
+ * @ignore
+ *
+ * @param {number} n - The value to convert.
+ * @param {number} h - The h value.
+ * @param {number} s - The s value.
+ * @param {number} v - The v value.
+ *
+ * @return {number} The converted value.
+ */
+function ConvertValue (n, h, s, v)
+{
+    var k = (n + h * 6) % 6;
+
+    var min = Math.min(k, 4 - k, 1);
+
+    return Math.round(255 * (v - v * s * Math.max(0, min)));
+}
+
+/**
+ * Converts a HSV (hue, saturation and value) color set to RGB.
+ *
+ * Conversion formula from https://en.wikipedia.org/wiki/HSL_and_HSV
+ *
  * Assumes HSV values are contained in the set [0, 1].
- * Based on code by Michael Jackson (https://github.com/mjijackson)
  *
  * @function Phaser.Display.Color.HSVToRGB
  * @since 3.0.0
@@ -27,51 +49,9 @@ var HSVToRGB = function (h, s, v, out)
     if (s === undefined) { s = 1; }
     if (v === undefined) { v = 1; }
 
-    var i = Math.floor(h * 6);
-    var f = h * 6 - i;
-
-    var p = Math.floor((v * (1 - s)) * 255);
-    var q = Math.floor((v * (1 - f * s)) * 255);
-    var t = Math.floor((v * (1 - (1 - f) * s)) * 255);
-
-    v = Math.floor(v *= 255);
-
-    var r = v;
-    var g = v;
-    var b = v;
-
-    var c = i % 6;
-
-    if (c === 0)
-    {
-        g = t;
-        b = p;
-    }
-    else if (c === 1)
-    {
-        r = q;
-        b = p;
-    }
-    else if (c === 2)
-    {
-        r = p;
-        b = t;
-    }
-    else if (c === 3)
-    {
-        r = p;
-        g = q;
-    }
-    else if (c === 4)
-    {
-        r = t;
-        g = p;
-    }
-    else if (c === 5)
-    {
-        g = p;
-        b = q;
-    }
+    var r = ConvertValue(5, h, s, v);
+    var g = ConvertValue(3, h, s, v);
+    var b = ConvertValue(1, h, s, v);
 
     if (!out)
     {