create parity between //snow and //thaw

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

@@ -54,6 +54,7 @@
 import com.sk89q.worldedit.function.block.Counter;
 import com.sk89q.worldedit.function.block.Naturalizer;
 import com.sk89q.worldedit.function.block.SnowSimulator;
+import com.sk89q.worldedit.function.block.Thawer;
 import com.sk89q.worldedit.function.generator.ForestGenerator;
 import com.sk89q.worldedit.function.generator.GardenPatchGenerator;
 import com.sk89q.worldedit.function.mask.BlockMask;
@@ -2075,49 +2076,24 @@ public final int thaw(BlockVector3 position, double radius)
      */
     public int thaw(BlockVector3 position, double radius, int height)
         throws MaxChangedBlocksException {
-        int affected = 0;
-        double radiusSq = radius * radius;
-
-        int ox = position.x();
-        int oy = position.y();
-        int oz = position.z();
-
-        BlockState air = BlockTypes.AIR.getDefaultState();
-        BlockState water = BlockTypes.WATER.getDefaultState();
-
-        int centerY = Math.max(getWorld().getMinY(), Math.min(getWorld().getMaxY(), oy));
-        int minY = Math.max(getWorld().getMinY(), centerY - height);
-        int maxY = Math.min(getWorld().getMaxY(), centerY + height);
-
-        int ceilRadius = (int) Math.ceil(radius);
-        for (int x = ox - ceilRadius; x <= ox + ceilRadius; ++x) {
-            for (int z = oz - ceilRadius; z <= oz + ceilRadius; ++z) {
-                if (BlockVector3.at(x, oy, z).distanceSq(position) > radiusSq) {
-                    continue;
-                }
-
-                for (int y = maxY; y > minY; --y) {
-                    BlockVector3 pt = BlockVector3.at(x, y, z);
-                    BlockType id = getBlock(pt).getBlockType();
 
-                    if (id == BlockTypes.ICE) {
-                        if (setBlock(pt, water)) {
-                            ++affected;
-                        }
-                    } else if (id == BlockTypes.SNOW) {
-                        if (setBlock(pt, air)) {
-                            ++affected;
-                        }
-                    } else if (id.getMaterial().isAir()) {
-                        continue;
-                    }
+        return thaw(new CylinderRegion(position, Vector2.at(radius, radius), position.y(), height));
+    }
 
-                    break;
-                }
-            }
-        }
+    /**
+     * Thaw blocks in a cylinder.
+     *
+     * @param region the region to thaw in
+     * @return number of blocks affected
+     * @throws MaxChangedBlocksException thrown if too many blocks are changed
+     */
+    public final int thaw(FlatRegion region) throws MaxChangedBlocksException {
+        checkNotNull(region);
 
-        return affected;
+        Thawer thawer = new Thawer(this);
+        LayerVisitor layerVisitor = new LayerVisitor(region, region.getMinimumY(), region.getMaximumY(), thawer);
+        Operations.completeLegacy(layerVisitor);
+        return thawer.getAffected();
     }
 
     /**

worldedit-core/src/main/java/com/sk89q/worldedit/command/UtilityCommands.java

@@ -335,7 +335,10 @@ public int thaw(Actor actor, LocalSession session, EditSession editSession,
         height = Math.max(1, height);
         we.checkMaxRadius(size);
 
-        int affected = editSession.thaw(session.getPlacementPosition(actor), size, height);
+        BlockVector3 position = session.getPlacementPosition(actor);
+
+        CylinderRegion region = new CylinderRegion(position, Vector2.at(size, size), position.y() - height, position.y() + height);
+        int affected = editSession.thaw(region);
         actor.printInfo(TranslatableComponent.of(
             "worldedit.thaw.removed", TextComponent.of(affected)
         ));

worldedit-core/src/main/java/com/sk89q/worldedit/function/block/Thawer.java

@@ -0,0 +1,83 @@
+/*
+ * 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 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.function.block;
+
+import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.extent.Extent;
+import com.sk89q.worldedit.function.LayerFunction;
+import com.sk89q.worldedit.math.BlockVector3;
+import com.sk89q.worldedit.world.block.BlockState;
+import com.sk89q.worldedit.world.block.BlockType;
+import com.sk89q.worldedit.world.block.BlockTypes;
+
+public class Thawer implements LayerFunction {
+
+    private final BlockState air = BlockTypes.AIR.getDefaultState();
+    private final BlockState water = BlockTypes.WATER.getDefaultState();
+
+    private final Extent extent;
+
+    private int affected;
+
+    /**
+     * Create a new instance.
+     *
+     * @param extent the extent to thaw in
+     */
+    public Thawer(Extent extent) {
+        this.extent = extent;
+        this.affected = 0;
+    }
+
+    public int getAffected() {
+        return this.affected;
+    }
+
+    @Override
+    public boolean isGround(BlockVector3 position) {
+        BlockState block = this.extent.getBlock(position);
+
+        // Stop searching when we hit anything non-air
+        return !block.getBlockType().getMaterial().isAir();
+    }
+
+    @Override
+    public boolean apply(BlockVector3 position, int depth) throws WorldEditException {
+        if (depth > 0) {
+            // We only care about the first layer.
+            return false;
+        }
+
+        BlockState block = this.extent.getBlock(position);
+        BlockType blockType = block.getBlockType();
+
+        if (blockType == BlockTypes.ICE) {
+            if (this.extent.setBlock(position, water)) {
+                affected++;
+            }
+        } else if (blockType == BlockTypes.SNOW) {
+            if (this.extent.setBlock(position, air)) {
+                affected++;
+            }
+        }
+
+        return false;
+    }
+}