Did some minor Vector optimization.

src/com/sk89q/worldedit/EditSession.java

@@ -1579,6 +1579,7 @@ public class EditSession {
     public int simulateSnow(Vector pos, int radius)
             throws MaxChangedBlocksException {
         int affected = 0;
+        int radiusSq = (int)Math.pow(radius, 2);
 
         int ox = pos.getBlockX();
         int oy = pos.getBlockY();
@@ -1589,7 +1590,7 @@ public class EditSession {
 
         for (int x = ox - radius; x <= ox + radius; x++) {
             for (int z = oz - radius; z <= oz + radius; z++) {
-                if ((new Vector(x, oy, z)).distance(pos) > radius) {
+                if ((new Vector(x, oy, z)).distanceSq(pos) > radiusSq) {
                     continue;
                 }
 

src/com/sk89q/worldedit/Vector.java

@@ -446,6 +446,18 @@ public class Vector {
                 Math.pow(pt.z - z, 2));
     }
 
+    /**
+     * Get the distance away from a point, squared.
+     *
+     * @param pt
+     * @return distance
+     */
+    public double distanceSq(Vector pt) {
+        return Math.pow(pt.x - x, 2) +
+                Math.pow(pt.y - y, 2) +
+                Math.pow(pt.z - z, 2);
+    }
+
     /**
      * Checks to see if a vector is contained with another.
      *