Add intersects method to Rectangle4i

Added compare methods to MathHelper

codechicken/lib/math/MathHelper.java

@@ -165,4 +165,14 @@ public class MathHelper
     {
         return (int) (d < 0 ? Math.floor(d) : Math.ceil(d));
     }
+    
+    public static int compare(int a, int b)
+    {
+        return a == b ? 0 : a < b ? -1 : 1;
+    }
+    
+    public static int compare(double a, double b)
+    {
+        return a == b ? 0 : a < b ? -1 : 1;
+    }
 }

codechicken/lib/vec/Rectangle4i.java

@@ -39,4 +39,10 @@ public class Rectangle4i
     {
         return x <= px && px < x+w && y <= py && py < y+h;
     }
+    
+    public boolean intersects(Rectangle4i r)
+    {
+    	return x <= r.x+r.w && r.x <= x+w &&
+    	          y <= r.y+r.h && r.y <= y+h;
+    }
 }