Fixes #950

core/src/main/java/com/boydti/fawe/object/function/block/CombinedBlockCopy.java

@@ -0,0 +1,27 @@
+package com.boydti.fawe.object.function.block;
+
+import com.sk89q.worldedit.Vector;
+import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.blocks.BaseBlock;
+import com.sk89q.worldedit.extent.Extent;
+import com.sk89q.worldedit.function.RegionFunction;
+
+public class CombinedBlockCopy implements RegionFunction {
+
+    protected final Extent source;
+    protected final Extent destination;
+    private final RegionFunction function;
+
+    public CombinedBlockCopy(Extent source, Extent destination, RegionFunction combined) {
+        this.source = source;
+        this.destination = destination;
+        this.function = combined;
+    }
+
+    @Override
+    public boolean apply(Vector position) throws WorldEditException {
+        BaseBlock block = source.getBlock(position);
+        function.apply(position);
+        return destination.setBlock(position, block);
+    }
+}

core/src/main/java/com/sk89q/worldedit/EditSession.java

@@ -1983,7 +1983,7 @@ public class EditSession extends AbstractDelegateExtent implements HasFaweQueue,
         final Vector displace = dir.multiply(distance);
 
         final Vector size = region.getMaximumPoint().subtract(region.getMinimumPoint()).add(1, 1, 1);
-        final Vector to = region.getMinimumPoint();
+        final Vector to = region.getMinimumPoint().add(dir.multiply(distance));
 
         Vector disAbs = displace.positive();
 
@@ -1992,32 +1992,15 @@ public class EditSession extends AbstractDelegateExtent implements HasFaweQueue,
             queue.dequeue();
         }
 
-
         final ForwardExtentCopy copy = new ForwardExtentCopy(EditSession.this, region, EditSession.this, to);
 
         if (replacement == null) replacement = nullBlock;
-        final BlockReplace remove = replacement instanceof ExistingPattern ? null : new BlockReplace(EditSession.this, replacement) {
-            private MutableBlockVector mutable = new MutableBlockVector();
-
-            @Override
-            // Only copy what's necessary
-            public boolean apply(Vector position) throws WorldEditException {
-                mutable.mutX((position.getX() - displace.getX()));
-                mutable.mutY((position.getY() - displace.getY()));
-                mutable.mutZ((position.getZ() - displace.getZ()));
-
-                if (copyAir && region.contains(mutable)) {
-                    return false;
-                }
-                return super.apply(position);
-            }
-        };
+        final BlockReplace remove = replacement instanceof ExistingPattern ? null : new BlockReplace(EditSession.this, replacement);
 
         copy.setCopyBiomes(copyBiomes);
         copy.setCopyEntities(copyEntities);
         copy.setSourceFunction(remove);
         copy.setRepetitions(1);
-        copy.setTransform(new AffineTransform().translate(dir.multiply(distance)));
         Mask sourceMask = getSourceMask();
         if (sourceMask != null) {
             new MaskTraverser(sourceMask).reset(EditSession.this);

core/src/main/java/com/sk89q/worldedit/function/CombinedRegionFunction.java

@@ -64,6 +64,9 @@ public class CombinedRegionFunction implements RegionFunction {
         if (function instanceof CombinedRegionFunction) {
             combined = ((CombinedRegionFunction) function);
             combined.add(add);
+        } else if (add instanceof CombinedRegionFunction) {
+            combined = new CombinedRegionFunction(function);
+            combined.add(((CombinedRegionFunction) add).functions);
         } else {
             combined = new CombinedRegionFunction(function, add);
         }

core/src/main/java/com/sk89q/worldedit/function/RegionMaskTestFunction.java

@@ -0,0 +1,64 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.function;
+
+import com.sk89q.worldedit.Vector;
+import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.function.mask.Mask;
+import com.sk89q.worldedit.regions.Region;
+
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Passes calls to {@link #apply(com.sk89q.worldedit.Vector)} to the
+ * delegate {@link com.sk89q.worldedit.function.RegionFunction} if they
+ * match the given mask.
+ */
+public class RegionMaskTestFunction implements RegionFunction {
+
+    private final RegionFunction pass,fail;
+    private Mask mask;
+
+    /**
+     * Create a new masking filter.
+     *
+     * @param mask the mask
+     * @param function the function
+     */
+    public RegionMaskTestFunction(Mask mask, RegionFunction success, RegionFunction failure) {
+        checkNotNull(success);
+        checkNotNull(failure);
+        checkNotNull(mask);
+        this.pass = success;
+        this.fail = failure;
+        this.mask = mask;
+    }
+
+    @Override
+    public boolean apply(Vector position) throws WorldEditException {
+        if (mask.test(position)) {
+            return pass.apply(position);
+        } else {
+            return fail.apply(position);
+        }
+    }
+
+}