remove mutability in clipboards (particularly clipboard pattern)

fixes #776

worldedit-core/src/main/java/com/boydti/fawe/object/clipboard/CPUOptimizedClipboard.java

@@ -116,14 +116,8 @@ public class CPUOptimizedClipboard extends LinearClipboard {
         return nbtMapIndex.get(index);
     }
 
-    private int yLast;
-    private int yLastI;
-    private int zLast;
-    private int zLastI;
-
     public int getIndex(int x, int y, int z) {
-        return x + ((yLast == y) ? yLastI : (yLastI = (yLast = y) * getArea())) + ((zLast == z) ? zLastI
-            : (zLastI = (zLast = z) * getWidth()));
+        return x + y * getArea() + z * getWidth();
     }
 
     @Override

worldedit-core/src/main/java/com/boydti/fawe/object/clipboard/DiskOptimizedClipboard.java

@@ -324,8 +324,7 @@ public class DiskOptimizedClipboard extends LinearClipboard implements Closeable
     }
 
     public int getIndex(int x, int y, int z) {
-        return x + (ylast == y ? ylasti : (ylasti = (ylast = y) * getArea())) + (zlast == z
-            ? zlasti : (zlasti = (zlast = z) * getWidth()));
+        return x + y * getArea() + z * getWidth();
     }
 
     @Override

worldedit-core/src/main/java/com/boydti/fawe/object/clipboard/MemoryOptimizedClipboard.java

@@ -193,13 +193,8 @@ public class MemoryOptimizedClipboard extends LinearClipboard {
         return nbtMap.values();
     }
 
-    private int ylast;
-    private int ylasti;
-    private int zlast;
-    private int zlasti;
-
     public int getIndex(int x, int y, int z) {
-        return x + ((ylast == y) ? ylasti : (ylasti = (ylast = y) * getArea())) + ((zlast == z) ? zlasti : (zlasti = (zlast = z) * getWidth()));
+        return x + y * getArea() + z * getWidth();
     }
 
     @Override

worldedit-core/src/main/java/com/sk89q/worldedit/function/pattern/RepeatingExtentPattern.java

@@ -32,7 +32,6 @@ import static com.google.common.base.Preconditions.checkNotNull;
 public class RepeatingExtentPattern extends AbstractExtentPattern {
 
     private final BlockVector3 size;
-    private final MutableBlockVector3 mutable;
     private BlockVector3 origin;
     private BlockVector3 offset;
 
@@ -47,7 +46,6 @@ public class RepeatingExtentPattern extends AbstractExtentPattern {
         setOrigin(origin);
         setOffset(offset);
         size = extent.getMaximumPoint().subtract(extent.getMinimumPoint()).add(1, 1, 1);
-        this.mutable = new MutableBlockVector3();
     }
 
     /**
@@ -93,7 +91,7 @@ public class RepeatingExtentPattern extends AbstractExtentPattern {
         int x = Math.abs(position.getX() + offset.getX()) % size.getBlockX() + origin.getX();
         int y = Math.abs(position.getY() + offset.getY()) % size.getBlockY() + origin.getY();
         int z = Math.abs(position.getZ() + offset.getZ()) % size.getBlockZ() + origin.getZ();
-        return getExtent().getFullBlock(mutable.setComponents(x, y, z));
+        return getExtent().getFullBlock(x, y, z);
     }
 
 }