From d82111a4fc9efe66f39232ed63c25d9d951393c2 Mon Sep 17 00:00:00 2001
From: aumgn <aumgn@free.fr>
Date: Thu, 15 Mar 2012 16:42:56 +0100
Subject: [PATCH] Fix a NPE with brush using a global mask and no brush mask

---
 .../com/sk89q/worldedit/tools/BrushTool.java  | 20 ++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/src/main/java/com/sk89q/worldedit/tools/BrushTool.java b/src/main/java/com/sk89q/worldedit/tools/BrushTool.java
index e90b5e21a..121242118 100644
--- a/src/main/java/com/sk89q/worldedit/tools/BrushTool.java
+++ b/src/main/java/com/sk89q/worldedit/tools/BrushTool.java
@@ -177,15 +177,17 @@ public class BrushTool implements TraceTool {
         BlockBag bag = session.getBlockBag(player);
 
         EditSession editSession = session.createEditSession(player);
-        Mask existingMask = editSession.getMask();
-        if (existingMask == null) {
-            editSession.setMask(mask);
-        } else if (existingMask instanceof CombinedMask) {
-            ((CombinedMask) existingMask).add(mask);
-        } else {
-            CombinedMask newMask = new CombinedMask(existingMask);
-            newMask.add(mask);
-            editSession.setMask(newMask);
+        if (mask != null) {
+            Mask existingMask = editSession.getMask();
+            if (existingMask == null) {
+                editSession.setMask(mask);
+            } else if (existingMask instanceof CombinedMask) {
+                ((CombinedMask) existingMask).add(mask);
+            } else {
+                CombinedMask newMask = new CombinedMask(existingMask);
+                newMask.add(mask);
+                editSession.setMask(newMask);
+            }
         }
 
         try {