Add morph brush (EngineHub#2078)

* Add erosion brush

* Rename to the Morph brush, and add Erode and Dilate presets

Co-authored-by: Lewis B <[email protected]>

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

@@ -2687,6 +2687,153 @@ protected BiomeType getBiome(int x, int y, int z, BiomeType defaultBiomeType) {
         return changed;
     }
 
+    public int morph(BlockVector3 position, double brushSize, int minErodeFaces, int numErodeIterations, int minDilateFaces, int numDilateIterations) throws MaxChangedBlocksException {
+        int ceilBrushSize = (int) Math.ceil(brushSize);
+        int bufferSize = ceilBrushSize * 2 + 3;  // + 1 due to checking the adjacent blocks, plus the 0th block
+        // Store block states in a 3d array so we can do multiple mutations then commit.
+        // Two are required as for each iteration, one is "current" and the other is "new"
+        BlockState[][][] currentBuffer = new BlockState[bufferSize][bufferSize][bufferSize];
+        BlockState[][][] nextBuffer = new BlockState[bufferSize][bufferSize][bufferSize];
+
+        // Simply used for swapping the two
+        BlockState[][][] tmp;
+
+        // Load into buffer
+        for (int x = 0; x < bufferSize; x++) {
+            for (int y = 0; y < bufferSize; y++) {
+                for (int z = 0; z < bufferSize; z++) {
+                    BlockState blockState = getBlock(position.add(x - ceilBrushSize - 1, y - ceilBrushSize - 1, z - ceilBrushSize - 1));
+                    currentBuffer[x][y][z] = blockState;
+                    nextBuffer[x][y][z] = blockState;
+                }
+            }
+        }
+
+        double brushSizeSq = brushSize * brushSize;
+        Map<BlockState, Integer> blockStateFrequency = new HashMap<>();
+        int totalFaces;
+        int highestFreq;
+        BlockState highestState;
+        for (int i = 0; i < numErodeIterations; i++) {
+            for (int x = 0; x <= ceilBrushSize * 2; x++) {
+                for (int y = 0; y <= ceilBrushSize * 2; y++) {
+                    for (int z = 0; z <= ceilBrushSize * 2; z++) {
+                        int realX = x - ceilBrushSize;
+                        int realY = y - ceilBrushSize;
+                        int realZ = z - ceilBrushSize;
+                        if (lengthSq(realX, realY, realZ) > brushSizeSq) {
+                            continue;
+                        }
+
+                        // Copy across changes
+                        nextBuffer[x + 1][y + 1][z + 1] = currentBuffer[x + 1][y + 1][z + 1];
+
+                        BlockState blockState = currentBuffer[x + 1][y + 1][z + 1];
+
+                        if (blockState.getBlockType().getMaterial().isLiquid() || blockState.getBlockType().getMaterial().isAir()) {
+                            continue;
+                        }
+
+                        blockStateFrequency.clear();
+                        totalFaces = 0;
+                        highestFreq = 0;
+                        highestState = blockState;
+                        for (BlockVector3 vec3 : recurseDirections) {
+                            BlockState adj = currentBuffer[x + 1 + vec3.getX()][y + 1 + vec3.getY()][z + 1 + vec3.getZ()];
+
+                            if (!adj.getBlockType().getMaterial().isLiquid() && !adj.getBlockType().getMaterial().isAir()) {
+                                continue;
+                            }
+
+                            totalFaces++;
+                            int newFreq = blockStateFrequency.getOrDefault(adj, 0) + 1;
+                            blockStateFrequency.put(adj, newFreq);
+
+                            if (newFreq > highestFreq) {
+                                highestFreq = newFreq;
+                                highestState = adj;
+                            }
+                        }
+
+                        if (totalFaces >= minErodeFaces) {
+                            nextBuffer[x + 1][y + 1][z + 1] = highestState;
+                        }
+                    }
+                }
+            }
+            // Swap current and next
+            tmp = currentBuffer;
+            currentBuffer = nextBuffer;
+            nextBuffer = tmp;
+        }
+
+        for (int i = 0; i < numDilateIterations; i++) {
+            for (int x = 0; x <= ceilBrushSize * 2; x++) {
+                for (int y = 0; y <= ceilBrushSize * 2; y++) {
+                    for (int z = 0; z <= ceilBrushSize * 2; z++) {
+                        int realX = x - ceilBrushSize;
+                        int realY = y - ceilBrushSize;
+                        int realZ = z - ceilBrushSize;
+                        if (lengthSq(realX, realY, realZ) > brushSizeSq) {
+                            continue;
+                        }
+
+                        // Copy across changes
+                        nextBuffer[x + 1][y + 1][z + 1] = currentBuffer[x + 1][y + 1][z + 1];
+
+                        BlockState blockState = currentBuffer[x + 1][y + 1][z + 1];
+                        // Needs to be empty
+                        if (!blockState.getBlockType().getMaterial().isLiquid() && !blockState.getBlockType().getMaterial().isAir()) {
+                            continue;
+                        }
+
+                        blockStateFrequency.clear();
+                        totalFaces = 0;
+                        highestFreq = 0;
+                        highestState = blockState;
+                        for (BlockVector3 vec3 : recurseDirections) {
+                            BlockState adj = currentBuffer[x + 1 + vec3.getX()][y + 1 + vec3.getY()][z + 1 + vec3.getZ()];
+                            if (adj.getBlockType().getMaterial().isLiquid() || adj.getBlockType().getMaterial().isAir()) {
+                                continue;
+                            }
+
+                            totalFaces++;
+                            int newFreq = blockStateFrequency.getOrDefault(adj, 0) + 1;
+                            blockStateFrequency.put(adj, newFreq);
+
+                            if (newFreq > highestFreq) {
+                                highestFreq = newFreq;
+                                highestState = adj;
+                            }
+                        }
+
+                        if (totalFaces >= minDilateFaces) {
+                            nextBuffer[x + 1][y + 1][z + 1] = highestState;
+                        }
+                    }
+                }
+            }
+            // Swap current and next
+            tmp = currentBuffer;
+            currentBuffer = nextBuffer;
+            nextBuffer = tmp;
+        }
+
+        // Commit to world
+        int changed = 0;
+        for (int x = 0; x < bufferSize; x++) {
+            for (int y = 0; y < bufferSize; y++) {
+                for (int z = 0; z < bufferSize; z++) {
+                    if (setBlock(position.add(x - ceilBrushSize - 1, y - ceilBrushSize - 1, z - ceilBrushSize - 1), currentBuffer[x][y][z])) {
+                        changed++;
+                    }
+                }
+            }
+        }
+
+        return changed;
+    }
+
     private static final BlockVector3[] recurseDirections = {
             Direction.NORTH.toBlockVector(),
             Direction.EAST.toBlockVector(),

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

@@ -34,6 +34,7 @@
 import com.sk89q.worldedit.command.tool.brush.HollowCylinderBrush;
 import com.sk89q.worldedit.command.tool.brush.HollowSphereBrush;
 import com.sk89q.worldedit.command.tool.brush.ImageHeightmapBrush;
+import com.sk89q.worldedit.command.tool.brush.MorphBrush;
 import com.sk89q.worldedit.command.tool.brush.OperationFactoryBrush;
 import com.sk89q.worldedit.command.tool.brush.SmoothBrush;
 import com.sk89q.worldedit.command.tool.brush.SnowSmoothBrush;
@@ -581,6 +582,62 @@ public void biome(Player player, LocalSession localSession,
         player.printInfo(TranslatableComponent.of("worldedit.setbiome.warning"));
     }
 
+    @Command(
+        name = "morph",
+        desc = "Morph brush, morphs blocks in the area"
+    )
+    @CommandPermissions("worldedit.brush.morph")
+    public void morph(Player player, LocalSession session,
+                      @Arg(desc = "The size of the brush", def = "5")
+                          double brushSize,
+                      @Arg(desc = "Minimum number of faces for erosion", def = "3")
+                          int minErodeFaces,
+                      @Arg(desc = "Erode iterations", def = "1")
+                          int numErodeIterations,
+                      @Arg(desc = "Minimum number of faces for dilation", def = "3")
+                          int minDilateFaces,
+                      @Arg(desc = "Dilate iterations", def = "1")
+                          int numDilateIterations) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(brushSize);
+        BrushTool tool = session.getBrushTool(player.getItemInHand(HandSide.MAIN_HAND).getType());
+        tool.setSize(brushSize);
+        tool.setBrush(new MorphBrush(minErodeFaces, numErodeIterations, minDilateFaces, numDilateIterations), "worldedit.brush.morph");
+
+        player.printInfo(TranslatableComponent.of("worldedit.brush.morph.equip", TextComponent.of((int) brushSize)));
+    }
+
+    @Command(
+        name = "erode",
+        desc = "Erode preset for morph brush, erodes blocks in the area"
+    )
+    @CommandPermissions("worldedit.brush.morph")
+    public void erode(Player player, LocalSession session,
+                      @Arg(desc = "The size of the brush", def = "5")
+                          double brushSize) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(brushSize);
+        BrushTool tool = session.getBrushTool(player.getItemInHand(HandSide.MAIN_HAND).getType());
+        tool.setSize(brushSize);
+        tool.setBrush(new MorphBrush(2, 1, 5, 1), "worldedit.brush.morph");
+
+        player.printInfo(TranslatableComponent.of("worldedit.brush.morph.equip", TextComponent.of((int) brushSize)));
+    }
+
+    @Command(
+        name = "dilate",
+        desc = "Dilate preset for morph brush, dilates blocks in the area"
+    )
+    @CommandPermissions("worldedit.brush.morph")
+    public void dilate(Player player, LocalSession session,
+                       @Arg(desc = "The size of the brush", def = "5")
+                           double brushSize) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(brushSize);
+        BrushTool tool = session.getBrushTool(player.getItemInHand(HandSide.MAIN_HAND).getType());
+        tool.setSize(brushSize);
+        tool.setBrush(new MorphBrush(5, 1, 2, 1), "worldedit.brush.morph");
+
+        player.printInfo(TranslatableComponent.of("worldedit.brush.morph.equip", TextComponent.of((int) brushSize)));
+    }
+
     static void setOperationBasedBrush(Player player, LocalSession session, double radius,
                                         Contextual<? extends Operation> factory,
                                         RegionFactory shape,

worldedit-core/src/main/java/com/sk89q/worldedit/command/tool/brush/MorphBrush.java

@@ -0,0 +1,46 @@
+/*
+ * 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.command.tool.brush;
+
+import com.sk89q.worldedit.EditSession;
+import com.sk89q.worldedit.MaxChangedBlocksException;
+import com.sk89q.worldedit.function.pattern.Pattern;
+import com.sk89q.worldedit.math.BlockVector3;
+
+public class MorphBrush implements Brush {
+
+    private final int minErodeFaces;
+    private final int numErodeIterations;
+    private final int minDilateFaces;
+    private final int minDilateIterations;
+
+    public MorphBrush(int minErodeFaces, int numErodeIterations, int minDilateFaces, int minDilateIterations) {
+        this.minErodeFaces = minErodeFaces;
+        this.numErodeIterations = numErodeIterations;
+        this.minDilateFaces = minDilateFaces;
+        this.minDilateIterations = minDilateIterations;
+    }
+
+    @Override
+    public void build(EditSession editSession, BlockVector3 position, Pattern pattern, double size) throws MaxChangedBlocksException {
+        editSession.morph(position, size, this.minErodeFaces, this.numErodeIterations, this.minDilateFaces, this.minDilateIterations);
+    }
+
+}

worldedit-core/src/main/resources/lang/strings.json

@@ -36,6 +36,7 @@
     "worldedit.brush.operation.equip": "Set brush to {0}.",
     "worldedit.brush.heightmap.equip": "Heightmap brush equipped ({0}).",
     "worldedit.brush.heightmap.unknown": "Unknown heightmap brush: {0}.",
+    "worldedit.brush.morph.equip": "Morph brush shape equipped: {0}.",
     "worldedit.brush.none.equip": "Brush unbound from your current item.",
 
     "worldedit.setbiome.changed": "Biomes were changed for approximately {0} blocks.",