Begin to implement extended world heights:

- Implemented in Bukkit module (and where required in Core module)

Bukkit/src/main/java/com/plotsquared/bukkit/generator/BukkitPlotGenerator.java

@@ -27,6 +27,7 @@ package com.plotsquared.bukkit.generator;
 
 import com.plotsquared.bukkit.queue.GenChunk;
 import com.plotsquared.bukkit.util.BukkitUtil;
+import com.plotsquared.bukkit.util.BukkitWorld;
 import com.plotsquared.core.PlotSquared;
 import com.plotsquared.core.generator.GeneratorWrapper;
 import com.plotsquared.core.generator.IndependentPlotGenerator;
@@ -159,12 +160,14 @@ public class BukkitPlotGenerator extends ChunkGenerator
             @NonNull BiomeGrid biome
     ) {
 
-        GenChunk result = new GenChunk();
+        int minY =  BukkitWorld.getMinWorldHeight(world);
+        int maxY =  BukkitWorld.getMaxWorldHeight(world);
+        GenChunk result = new GenChunk(minY, maxY);
         if (this.getPlotGenerator() instanceof SingleWorldGenerator) {
             if (result.getChunkData() != null) {
                 for (int chunkX = 0; chunkX < 16; chunkX++) {
                     for (int chunkZ = 0; chunkZ < 16; chunkZ++) {
-                        for (int y = 0; y < world.getMaxHeight(); y++) {
+                        for (int y = minY; y < maxY; y++) {
                             biome.setBiome(chunkX, y, chunkZ, Biome.PLAINS);
 
                         }

Bukkit/src/main/java/com/plotsquared/bukkit/listener/BlockEventListener.java

@@ -354,7 +354,7 @@ public class BlockEventListener implements Listener {
         Plot plot = area.getPlot(location);
         if (plot != null) {
             BukkitPlayer plotPlayer = BukkitUtil.adapt(player);
-            if (event.getBlock().getY() == 0) {
+            if (event.getBlock().getY() == area.getMinBuildHeight()) {
                 if (!Permissions
                         .hasPermission(plotPlayer, Permission.PERMISSION_ADMIN_DESTROY_GROUNDLEVEL)) {
                     plotPlayer.sendMessage(
@@ -649,7 +649,7 @@ public class BlockEventListener implements Listener {
                     event.getBlock().breakNaturally();
                 }
             }
-            if (location.getY() == 0) {
+            if (location.getY() == area.getMinBuildHeight()) {
                 event.setCancelled(true);
                 return;
             }

Bukkit/src/main/java/com/plotsquared/bukkit/queue/BukkitQueueCoordinator.java

@@ -111,8 +111,8 @@ public class BukkitQueueCoordinator extends BasicQueueCoordinator {
     public boolean enqueue() {
         final Clipboard regenClipboard;
         if (isRegen()) {
-            BlockVector3 start = BlockVector3.at(getRegenStart()[0] << 4, 0, getRegenStart()[1] << 4);
+            BlockVector3 start = BlockVector3.at(getRegenStart()[0] << 4, getWorld().getMinY(), getRegenStart()[1] << 4);
-            BlockVector3 end = BlockVector3.at((getRegenEnd()[0] << 4) + 15, 255, (getRegenEnd()[1] << 4) + 15);
+            BlockVector3 end = BlockVector3.at((getRegenEnd()[0] << 4) + 15, getWorld().getMaxY(), (getRegenEnd()[1] << 4) + 15);
             Region region = new CuboidRegion(start, end);
             regenClipboard = new BlockArrayClipboard(region);
             regenClipboard.setOrigin(start);
@@ -134,7 +134,7 @@ public class BukkitQueueCoordinator extends BasicQueueCoordinator {
                 int sx = blockVector2.getX() << 4;
                 int sz = blockVector2.getZ() << 4;
                 if (isRegenChunk) {
-                    for (int layer = 0; layer < 16; layer++) {
+                    for (int layer = (getWorld().getMinY() >> 4); layer < (getWorld().getMaxY() >> 4); layer++) {
                         for (int y = 0; y < 16; y++) {
                             for (int x = 0; x < 16; x++) {
                                 for (int z = 0; z < 16; z++) {
@@ -170,7 +170,7 @@ public class BukkitQueueCoordinator extends BasicQueueCoordinator {
                             int lx = ChunkUtil.getX(j);
                             int lz = ChunkUtil.getZ(j);
                             int x = sx + lx;
-                            int y = ChunkUtil.getY(layer, j);
+                            int y = ChunkUtil.getY(layer + localChunk.getMinSection(), j);
                             int z = sz + lz;
                             boolean edge = Settings.QUEUE.UPDATE_EDGES && isEdge(y >> 4, lx, y & 15, lz, blockVector2,
                                     localChunk
@@ -295,47 +295,48 @@ public class BukkitQueueCoordinator extends BasicQueueCoordinator {
     }
 
     private boolean isEdge(int layer, int x, int y, int z, BlockVector2 blockVector2, LocalChunk localChunk) {
-        if (layer == 0 || layer == localChunk.getBaseblocks().length - 1) {
+        int layerIndex = (layer - localChunk.getMinSection());
+        if (layer == localChunk.getMinSection() || layerIndex == localChunk.getBaseblocks().length - 1) {
             return false;
         }
         if (x == 0) {
             LocalChunk localChunkX = getBlockChunks().get(blockVector2.withX(blockVector2.getX() - 1));
-            if (localChunkX == null || localChunkX.getBaseblocks()[layer] == null ||
+            if (localChunkX == null || localChunkX.getBaseblocks()[layerIndex] == null ||
-                    localChunkX.getBaseblocks()[layer][ChunkUtil.getJ(15, y, z)] != null) {
+                    localChunkX.getBaseblocks()[layerIndex][ChunkUtil.getJ(15, y, z)] != null) {
                 return true;
             }
         } else if (x == 15) {
             LocalChunk localChunkX = getBlockChunks().get(blockVector2.withX(blockVector2.getX() + 1));
-            if (localChunkX == null || localChunkX.getBaseblocks()[layer] == null ||
+            if (localChunkX == null || localChunkX.getBaseblocks()[layerIndex] == null ||
-                    localChunkX.getBaseblocks()[layer][ChunkUtil.getJ(0, y, z)] != null) {
+                    localChunkX.getBaseblocks()[layerIndex][ChunkUtil.getJ(0, y, z)] != null) {
                 return true;
             }
         }
         if (z == 0) {
             LocalChunk localChunkZ = getBlockChunks().get(blockVector2.withZ(blockVector2.getZ() - 1));
-            if (localChunkZ == null || localChunkZ.getBaseblocks()[layer] == null ||
+            if (localChunkZ == null || localChunkZ.getBaseblocks()[layerIndex] == null ||
-                    localChunkZ.getBaseblocks()[layer][ChunkUtil.getJ(x, y, 15)] != null) {
+                    localChunkZ.getBaseblocks()[layerIndex][ChunkUtil.getJ(x, y, 15)] != null) {
                 return true;
             }
         } else if (z == 15) {
             LocalChunk localChunkZ = getBlockChunks().get(blockVector2.withZ(blockVector2.getZ() + 1));
-            if (localChunkZ == null || localChunkZ.getBaseblocks()[layer] == null ||
+            if (localChunkZ == null || localChunkZ.getBaseblocks()[layerIndex] == null ||
-                    localChunkZ.getBaseblocks()[layer][ChunkUtil.getJ(x, y, 0)] != null) {
+                    localChunkZ.getBaseblocks()[layerIndex][ChunkUtil.getJ(x, y, 0)] != null) {
                 return true;
             }
         }
         if (y == 0) {
-            if (localChunk.getBaseblocks()[layer - 1] == null ||
+            if (localChunk.getBaseblocks()[layerIndex - 1] == null ||
-                    localChunk.getBaseblocks()[layer][ChunkUtil.getJ(x, 15, z)] != null) {
+                    localChunk.getBaseblocks()[layerIndex][ChunkUtil.getJ(x, 15, z)] != null) {
                 return true;
             }
         } else if (y == 15) {
-            if (localChunk.getBaseblocks()[layer + 1] == null ||
+            if (localChunk.getBaseblocks()[layerIndex + 1] == null ||
-                    localChunk.getBaseblocks()[layer][ChunkUtil.getJ(x, 0, z)] != null) {
+                    localChunk.getBaseblocks()[layerIndex][ChunkUtil.getJ(x, 0, z)] != null) {
                 return true;
             }
         }
-        BaseBlock[] baseBlocks = localChunk.getBaseblocks()[layer];
+        BaseBlock[] baseBlocks = localChunk.getBaseblocks()[layerIndex];
         if (x > 0 && baseBlocks[ChunkUtil.getJ(x - 1, y, z)] == null) {
             return true;
         }

Bukkit/src/main/java/com/plotsquared/bukkit/queue/GenChunk.java

@@ -61,8 +61,28 @@ public class GenChunk extends ScopedQueueCoordinator {
     public int chunkZ;
     private ChunkData chunkData = null;
 
+
+    /**
+     * Not API. Used as a bridge between P2 and Bukkit {@link Chunk}.
+     *
+     * @deprecated Use {@link GenChunk#regenChunk(int, int)} for extended world heights
+     * @since TODO
+     */
+    @Deprecated(forRemoval = true, since = "TODO")
     public GenChunk() {
-        super(null, Location.at("", 0, 0, 0), Location.at("", 15, 255, 15));
+        this(0, 255);
+    }
+
+    /**
+     * Not API. Used as a bridge between P2 and Bukkit {@link Chunk}.
+     *
+     * @param minY minimum world Y, inclusive
+     * @param maxY maximum world Y, inclusive
+     *
+     * @since TODO
+     */
+    public GenChunk(int minY, int maxY) {
+        super(null, Location.at("", 0, minY, 0), Location.at("", 15, maxY, 15));
         this.biomes = Biome.values();
     }
 
@@ -117,7 +137,7 @@ public class GenChunk extends ScopedQueueCoordinator {
             return;
         }
         Biome biome = BukkitAdapter.adapt(biomeType);
-        for (int y = 0; y < 256; y++) {
+        for (int y = getMin().getY(); y <= getMax().getY(); y++) {
             for (int x = 0; x < 16; x++) {
                 for (int z = 0; z < 16; z++) {
                     this.biomeGrid.setBiome(x, y, z, biome);
@@ -130,7 +150,7 @@ public class GenChunk extends ScopedQueueCoordinator {
     public void setCuboid(@NonNull Location pos1, @NonNull Location pos2, @NonNull BlockState block) {
         if (result != null && pos1.getX() == 0 && pos1.getZ() == 0 && pos2.getX() == 15 && pos2.getZ() == 15) {
             for (int y = pos1.getY(); y <= pos2.getY(); y++) {
-                int layer = y >> 4;
+                int layer = (y - getMin().getY()) >> 4;
                 BlockState[] data = result[layer];
                 if (data == null) {
                     result[layer] = data = new BlockState[4096];
@@ -164,7 +184,7 @@ public class GenChunk extends ScopedQueueCoordinator {
      */
     public boolean setBiome(int x, int z, @NonNull Biome biome) {
         if (this.biomeGrid != null) {
-            for (int y = 0; y < 256; y++) {
+            for (int y = getMin().getY(); y < getMax().getY(); y++) {
                 this.setBiome(x, y, z, biome);
             }
             return true;
@@ -197,7 +217,7 @@ public class GenChunk extends ScopedQueueCoordinator {
     }
 
     private void storeCache(final int x, final int y, final int z, final @NonNull BlockState id) {
-        int i = y >> 4;
+        int i = (y - getMin().getY()) >> 4;
         BlockState[] v = this.result[i];
         if (v == null) {
             this.result[i] = v = new BlockState[4096];
@@ -219,7 +239,7 @@ public class GenChunk extends ScopedQueueCoordinator {
 
     @Override
     public @Nullable BlockState getBlock(int x, int y, int z) {
-        int i = y >> 4;
+        int i = (y - getMin().getY()) >> 4;
         if (result == null) {
             return BukkitBlockUtil.get(chunkData.getType(x, y, z));
         }
@@ -246,16 +266,16 @@ public class GenChunk extends ScopedQueueCoordinator {
 
     @Override
     public @NonNull Location getMax() {
-        return Location.at(getWorld().getName(), 15 + (getX() << 4), 255, 15 + (getZ() << 4));
+        return Location.at(getWorld().getName(), 15 + (getX() << 4), super.getMax().getY(), 15 + (getZ() << 4));
     }
 
     @Override
     public @NonNull Location getMin() {
-        return Location.at(getWorld().getName(), getX() << 4, 0, getZ() << 4);
+        return Location.at(getWorld().getName(), getX() << 4, super.getMin().getY(), getZ() << 4);
     }
 
     public @NonNull GenChunk clone() {
-        GenChunk toReturn = new GenChunk();
+        GenChunk toReturn = new GenChunk(getMin().getY(), getMax().getY());
         if (this.result != null) {
             for (int i = 0; i < this.result.length; i++) {
                 BlockState[] matrix = this.result[i];

Bukkit/src/main/java/com/plotsquared/bukkit/util/BukkitRegionManager.java

@@ -276,7 +276,9 @@ public class BukkitRegionManager extends RegionManager {
                                     PlotLoc plotLoc = new PlotLoc(bx + x1, bz + z1);
                                     BaseBlock[] ids = map.allBlocks.get(plotLoc);
                                     if (ids != null) {
-                                        for (int y = 0; y < Math.min(128, ids.length); y++) {
+                                        int minY = value.getMin().getY();
+                                        for (int yIndex = 0; yIndex < Math.min(128 - minY, ids.length); yIndex++) {
+                                            int y = yIndex + minY;
                                             BaseBlock id = ids[y];
                                             if (id != null) {
                                                 value.setBlock(x1, y, z1, id);
@@ -284,7 +286,8 @@ public class BukkitRegionManager extends RegionManager {
                                                 value.setBlock(x1, y, z1, BlockTypes.AIR.getDefaultState());
                                             }
                                         }
-                                        for (int y = Math.min(128, ids.length); y < ids.length; y++) {
+                                        for (int yIndex = Math.min(128 - minY, ids.length); yIndex < ids.length; yIndex++) {
+                                            int y = yIndex + minY;
                                             BaseBlock id = ids[y];
                                             if (id != null) {
                                                 value.setBlock(x1, y, z1, id);

Bukkit/src/main/java/com/plotsquared/bukkit/util/BukkitUtil.java

@@ -246,7 +246,9 @@ public class BukkitUtil extends WorldUtil {
             final World bukkitWorld = Objects.requireNonNull(getWorld(world));
             // Skip top and bottom block
             int air = 1;
-            for (int y = bukkitWorld.getMaxHeight() - 1; y >= 0; y--) {
+            int maxY = com.plotsquared.bukkit.util.BukkitWorld.getMaxWorldHeight(bukkitWorld);
+            int minY = com.plotsquared.bukkit.util.BukkitWorld.getMinWorldHeight(bukkitWorld);
+            for (int y = maxY - 1; y >= minY; y--) {
                 Block block = bukkitWorld.getBlockAt(x, y, z);
                 Material type = block.getType();
                 if (type.isSolid()) {
@@ -273,7 +275,9 @@ public class BukkitUtil extends WorldUtil {
         final World bukkitWorld = Objects.requireNonNull(getWorld(world));
         // Skip top and bottom block
         int air = 1;
-        for (int y = bukkitWorld.getMaxHeight() - 1; y >= 0; y--) {
+        int maxY = com.plotsquared.bukkit.util.BukkitWorld.getMaxWorldHeight(bukkitWorld);
+        int minY = com.plotsquared.bukkit.util.BukkitWorld.getMinWorldHeight(bukkitWorld);
+        for (int y = maxY - 1; y >= minY; y--) {
             Block block = bukkitWorld.getBlockAt(x, y, z);
             Material type = block.getType();
             if (type.isSolid()) {

Bukkit/src/main/java/com/plotsquared/bukkit/util/BukkitWorld.java

@@ -36,6 +36,18 @@ import java.util.Objects;
 public class BukkitWorld implements World<org.bukkit.World> {
 
     private static final Map<String, BukkitWorld> worldMap = Maps.newHashMap();
+    private static final boolean HAS_MIN_Y;
+
+    static {
+        boolean temp;
+        try {
+            org.bukkit.World.class.getMethod("getMinHeight");
+            temp = true;
+        } catch (NoSuchMethodException e) {
+            temp = false;
+        }
+        HAS_MIN_Y = temp;
+    }
 
     private final org.bukkit.World world;
 
@@ -73,6 +85,24 @@ public class BukkitWorld implements World<org.bukkit.World> {
         return bukkitWorld;
     }
 
+    /**
+     * Get the min world height from a Bukkit {@link org.bukkit.World}. Inclusive
+     *
+     * @since TODO
+     */
+    public static int getMinWorldHeight(org.bukkit.World world) {
+        return HAS_MIN_Y ? world.getMinHeight() : 0;
+    }
+
+    /**
+     * Get the max world height from a Bukkit {@link org.bukkit.World}. Exclusive
+     *
+     * @since TODO
+     */
+    public static int getMaxWorldHeight(org.bukkit.World world) {
+        return HAS_MIN_Y ? world.getMaxHeight() : 256;
+    }
+
     @Override
     public org.bukkit.World getPlatformWorld() {
         return this.world;
@@ -83,6 +113,16 @@ public class BukkitWorld implements World<org.bukkit.World> {
         return this.world.getName();
     }
 
+    @Override
+    public int getMinHeight() {
+        return getMinWorldHeight(world);
+    }
+
+    @Override
+    public int getMaxHeight() {
+        return getMaxWorldHeight(world);
+    }
+
     @Override
     public boolean equals(final Object o) {
         if (this == o) {

Bukkit/src/main/java/com/plotsquared/bukkit/util/ContentMap.java

@@ -70,7 +70,7 @@ public class ContentMap {
         }
         for (int x = x1; x <= x2; x++) {
             for (int z = z1; z <= z2; z++) {
-                saveBlocks(world, 256, x, z, 0, 0);
+                saveBlocks(world, x, z, 0, 0);
             }
         }
     }
@@ -134,13 +134,11 @@ public class ContentMap {
         this.entities.clear();
     }
 
-    //todo optimize maxY
+    private void saveBlocks(BukkitWorld world, int x, int z, int offsetX, int offsetZ) {
-    void saveBlocks(BukkitWorld world, int maxY, int x, int z, int offsetX, int offsetZ) {
+        BaseBlock[] ids = new BaseBlock[world.getMaxY() - world.getMinY()];
-        maxY = Math.min(255, maxY);
+        for (short yIndex = 0; yIndex <= world.getMaxY() - world.getMinY(); yIndex++) {
-        BaseBlock[] ids = new BaseBlock[maxY + 1];
+            BaseBlock block = world.getFullBlock(BlockVector3.at(x, yIndex + world.getMinY(), z));
-        for (short y = 0; y <= maxY; y++) {
+            ids[yIndex] = block;
-            BaseBlock block = world.getFullBlock(BlockVector3.at(x, y, z));
-            ids[y] = block;
         }
         PlotLoc loc = new PlotLoc(x + offsetX, z + offsetZ);
         this.allBlocks.put(loc, ids);

Core/src/main/java/com/plotsquared/core/location/World.java

@@ -58,6 +58,21 @@ public interface World<T> {
      */
     @NonNull String getName();
 
+    /**
+     * Get the min world height. Inclusive.
+     *
+     * @since TODO
+     */
+    int getMinHeight();
+
+
+    /**
+     * Get the max world height. Exclusive.
+     *
+     * @since TODO
+     */
+    int getMaxHeight();
+
     class NullWorld<T> implements World<T> {
 
         private NullWorld() {
@@ -74,6 +89,16 @@ public interface World<T> {
             return "";
         }
 
+        @Override
+        public int getMinHeight() {
+            return 0;
+        }
+
+        @Override
+        public int getMaxHeight() {
+            return 0;
+        }
+
         @Override
         public boolean equals(final Object obj) {
             return obj instanceof NullWorld;

Core/src/main/java/com/plotsquared/core/queue/LocalChunk.java

@@ -42,6 +42,7 @@ public class LocalChunk {
     private final QueueCoordinator parent;
     private final int x;
     private final int z;
+    private final int minSection;
 
     private final BaseBlock[][] baseblocks;
     private final BiomeType[][] biomes;
@@ -52,8 +53,10 @@ public class LocalChunk {
         this.parent = parent;
         this.x = x;
         this.z = z;
-        baseblocks = new BaseBlock[16][];
+        this.minSection = parent.getWorld() != null ? (parent.getWorld().getMinY() >> 4) : 0;
-        biomes = new BiomeType[16][];
+        int sections = parent.getWorld() != null ? (parent.getWorld().getMaxY() >> 4) - minSection : 16;
+        baseblocks = new BaseBlock[sections][];
+        biomes = new BiomeType[sections][];
     }
 
     public @NonNull QueueCoordinator getParent() {
@@ -68,6 +71,13 @@ public class LocalChunk {
         return this.z;
     }
 
+    /**
+     * Get the minimum layer position stored (usually -4 or 0).
+     */
+    public int getMinSection() {
+        return this.minSection;
+    }
+
     public @NonNull BaseBlock[][] getBaseblocks() {
         return this.baseblocks;
     }

Core/src/main/java/com/plotsquared/core/queue/ScopedQueueCoordinator.java

@@ -39,6 +39,8 @@ import org.checkerframework.checker.nullness.qual.Nullable;
  */
 public class ScopedQueueCoordinator extends DelegateQueueCoordinator {
 
+    private final Location min;
+    private final Location max;
     private final int minX;
     private final int minY;
     private final int minZ;
@@ -53,6 +55,8 @@ public class ScopedQueueCoordinator extends DelegateQueueCoordinator {
 
     public ScopedQueueCoordinator(@Nullable QueueCoordinator parent, @NonNull Location min, @NonNull Location max) {
         super(parent);
+        this.min = min;
+        this.max = max;
         this.minX = min.getX();
         this.minY = min.getY();
         this.minZ = min.getZ();
@@ -112,11 +116,11 @@ public class ScopedQueueCoordinator extends DelegateQueueCoordinator {
     }
 
     public @NonNull Location getMin() {
-        return Location.at(this.getWorld().getName(), this.minX, this.minY, this.minZ);
+        return min;
     }
 
     public @NonNull Location getMax() {
-        return Location.at(this.getWorld().getName(), this.maxX, this.maxY, this.maxZ);
+        return max;
     }
 
 }

Core/src/main/java/com/plotsquared/core/util/ChunkUtil.java

@@ -39,13 +39,13 @@ public class ChunkUtil {
      * - Used for efficient world generation<br>
      */
     private static final short[] x_loc;
-    private static final short[][] y_loc;
+    private static final short[] y_loc;
     private static final short[] z_loc;
     private static final short[][][] CACHE_J;
 
     static {
         x_loc = new short[4096];
-        y_loc = new short[16][4096];
+        y_loc = new short[4096];
         z_loc = new short[4096];
         for (int i = 0; i < 16; i++) {
             int i4 = i << 4;
@@ -55,14 +55,14 @@ public class ChunkUtil {
                 int z1 = a >> 4;
                 int x1 = a - (z1 << 4);
                 x_loc[j] = (short) x1;
-                y_loc[i][j] = (short) y;
+                y_loc[j] = (short) y;
                 z_loc[j] = (short) z1;
             }
         }
-        CACHE_J = new short[256][16][16];
+        CACHE_J = new short[16][16][16];
         for (int x = 0; x < 16; x++) {
             for (int z = 0; z < 16; z++) {
-                for (int y = 0; y < 256; y++) {
+                for (int y = 0; y < 16; y++) {
                     short j = (short) ((y & 0xF) << 8 | z << 4 | x);
                     CACHE_J[y][x][z] = j;
                 }
@@ -83,7 +83,7 @@ public class ChunkUtil {
      * @return J value for xyz position in Array[4096].
      */
     public static int getJ(int x, int y, int z) {
-        return CACHE_J[y][x][z];
+        return CACHE_J[y & 15][x & 15][z & 15];
     }
 
     /**
@@ -97,14 +97,14 @@ public class ChunkUtil {
     }
 
     /**
-     * Gets the y coordinate for specific I and J values for a Chunk 16x16x16x16 layerxyz Array[16][4096].
+     * Gets the y coordinate for specific I and J values for a Chunk 16x16x16x16 layerxyz Array[N][4096].
      *
-     * @param i Relative layer of the position in the layerxyz Array[16][4096].
+     * @param i Relative layer of the position in the layerxyz Array[16][4096]. May be negative.
      * @param j Position in the xyz Array[4096].
      * @return x coordinate within the chunk
      */
     public static int getY(int i, int j) {
-        return y_loc[i][j];
+        return (i << 4) + y_loc[j];
     }
 
     /**