v0.6.3: significant refactoring and performance improvements to fog of war

SPD-classes/src/main/java/com/watabou/utils/Rect.java

@@ -99,6 +99,15 @@ public class Rect {
 		return result;
 	}
 	
+	public Rect union( Rect other ){
+		Rect result = new Rect();
+		result.left		= Math.min( left, other.left );
+		result.right	= Math.max( right, other.right );
+		result.top		= Math.min( top, other.top );
+		result.bottom	= Math.max( bottom, other.bottom );
+		return result;
+	}
+	
 	public Rect union( int x, int y ) {
 		if (isEmpty()) {
 			return set( x, y, x + 1, y + 1 );