fix on overlays coloring (center is in white)

CHANGELOG

+minerva (10.0.4) stable; urgency=medium
+
+  * Bug fix: overlays colors are centered in white (not black)
+
+ -- Piotr Gawron <piotr.gawron@uni.lu>  Fri, 16 Dec 2016 10:01:16 +0200
+
 minerva (10.0.3) stable; urgency=medium
 
   * Bug fix: login cannot contain whitespace

persist/src/db/10.0.4/fix_db_20161215.sql

+-- empty file to force directory to be commited to git repo

web/src/main/webapp/resources/js/Functions.js

@@ -167,20 +167,26 @@ overlayToColor = function(elementOverlay) {
       ratio = elementOverlay.value;
       color = ServerConnector.getMaxOverlayColorInt();
     }
-    var red = color & 0xFF0000;
-    red = red*ratio;
+    ratio = 1 - ratio
+    var MAX_RED =   0xFF0000;
+    var MAX_GREEN = 0x00FF00;
+    var MAX_BLUE =  0x0000FF;
+
+    var red = color & MAX_RED;
+
+    red = red+ (MAX_RED-red)* ratio;
     red = parseInt(red);
     red = red & 0xFF0000;
 
-    var green = color & 0x00FF00;
-    green = green*ratio;
+    var green = color & MAX_GREEN;
+    green = green + (MAX_GREEN-green)* ratio;
     green = parseInt(green);
-    green = green & 0x00FF00;
+    green = green & MAX_GREEN;
 
-    var blue = color & 0x0000FF;
-    blue = blue*ratio;
+    var blue = color & MAX_BLUE;
+    blue = blue + (MAX_BLUE-blue)* ratio;
     blue = parseInt(blue);
-    blue = blue & 0x0000FF;
+    blue = blue & MAX_BLUE;
 
     var color = red | green | blue;
     return intToColorString(color);