#130 Fix color higher than 255

library/Phue/Helper/ColorConversion.php

@@ -59,7 +59,7 @@ public static function convertRGBToXY($red, $green, $blue)
             'bri' => round($xyz['y'] * 255)
         );
     }
-
+    
     /**
      * Converts XY (and brightness) values to RGB
      *
@@ -76,24 +76,33 @@ public static function convertXYToRGB($x, $y, $bri = 255)
         $xyz['y'] = $bri / 255;
         $xyz['x'] = ($xyz['y'] / $y) * $x;
         $xyz['z'] = ($xyz['y'] / $y) * $z;
-
+        
         // Convert to RGB using Wide RGB D65 conversion
         $color['red'] = $xyz['x'] * 1.656492 - $xyz['y'] * 0.354851 - $xyz['z'] * 0.255038;
         $color['green'] = -$xyz['x'] * 0.707196 + $xyz['y'] * 1.655397 + $xyz['z'] * 0.036152;
         $color['blue'] = $xyz['x'] * 0.051713 - $xyz['y'] * 0.121364 + $xyz['z'] * 1.011530;
-
+
+        $maxValue = 0;
         foreach ($color as $key => $normalized) {
             // Apply reverse gamma correction
             if ($normalized <= 0.0031308) {
                 $color[$key] = 12.92 * $normalized;
             } else {
                 $color[$key] = (1.0 + 0.055) * pow($normalized, 1.0 / 2.4) - 0.055;
             }
-
+            $color[$key] = max(0, $color[$key]);
+            if ($maxValue < $color[$key]) {
+                $maxValue = $color[$key];
+            }
+        }
+        foreach ($color as $key => $normalized) {
+            if ($maxValue > 1) {
+                $color[$key] /= $maxValue;
+            }
             // Scale back from a maximum of 1 to a maximum of 255
             $color[$key] = round($color[$key] * 255);
         }
-
+        
         return $color;
     }
 }

tests/Phue/Test/Helper/ColorConversionTest.php

@@ -68,5 +68,12 @@ public function testConvertXYToRGB()
         $this->assertEquals($rgb['red'], 61);
         $this->assertEquals($rgb['green'], 178);
         $this->assertEquals($rgb['blue'], 112);
+
+        // Test to make sure single RGB values falls within 0..255 range.
+        // old situation this was r -18, g 186, b -613.
+        $rgb = ColorConversion::convertXYToRGB(0.1979, 1.5005, 81);
+        $this->assertEquals($rgb['red'], 0);
+        $this->assertEquals($rgb['green'], 186);
+        $this->assertEquals($rgb['blue'], 0);
     }
 }