Fix no light for non full blocks (#1414)

bukkit/src/main/java/us/myles/ViaVersion/bukkit/platform/BukkitViaConfig.java

@@ -269,4 +269,9 @@ public class BukkitViaConfig extends Config implements ViaVersionConfig {
     public boolean is1_14HitboxFix() {
         return getBoolean("change-1_14-hitbox", false);
     }
+
+    @Override
+    public boolean isNonFullBlockLightFix() {
+        return getBoolean("fix-non-full-blocklight", true);
+    }
 }

bungee/src/main/java/us/myles/ViaVersion/bungee/platform/BungeeViaConfig.java

@@ -322,4 +322,9 @@ public class BungeeViaConfig extends Config implements ViaVersionConfig {
     public boolean is1_14HitboxFix() {
         return false;
     }
+
+    @Override
+    public boolean isNonFullBlockLightFix() {
+        return getBoolean("fix-non-full-blocklight", true);
+    }
 }

common/src/main/java/us/myles/ViaVersion/api/ViaVersionConfig.java

@@ -337,4 +337,11 @@ public interface ViaVersionConfig {
      * @return True if enabled
      */
     boolean is1_14HitboxFix();
+
+    /**
+     * Fixes non full blocks having 0 light for 1.14+ clients on sub 1.14 servers.
+     *
+     * @return True if enabled
+     */
+    boolean isNonFullBlockLightFix();
 }

common/src/main/java/us/myles/ViaVersion/api/minecraft/chunks/ChunkSection.java

@@ -175,10 +175,18 @@ public class ChunkSection {
         return blockLight == null ? null : blockLight.getHandle();
     }
 
+    public NibbleArray getBlockLightNibbleArray() {
+        return blockLight;
+    }
+
     public byte[] getSkyLight() {
         return skyLight == null ? null : skyLight.getHandle();
     }
 
+    public NibbleArray getSkyLightNibbleArray() {
+        return skyLight;
+    }
+
     public void readBlockLight(ByteBuf input) {
         if (this.blockLight == null) {
             this.blockLight = new NibbleArray(LIGHT_LENGTH * 2);
@@ -193,7 +201,7 @@ public class ChunkSection {
         input.readBytes(this.skyLight.getHandle());
     }
 
-    private static int index(int x, int y, int z) {
+    public static int index(int x, int y, int z) {
         return y << 8 | z << 4 | x;
     }
 

common/src/main/java/us/myles/ViaVersion/api/minecraft/chunks/NibbleArray.java

@@ -30,7 +30,7 @@ public class NibbleArray {
      * @return The value at the given XYZ
      */
     public byte get(int x, int y, int z) {
-        return get(y << 8 | z << 4 | x);
+        return get(ChunkSection.index(x, y, z));
     }
 
     /**
@@ -57,7 +57,7 @@ public class NibbleArray {
      * @param value Desired Value
      */
     public void set(int x, int y, int z, int value) {
-        set(y << 8 | z << 4 | x, value);
+        set(ChunkSection.index(x, y, z), value);
     }
 
     /**

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_14to1_13_2/Protocol1_14To1_13_2.java

@@ -323,6 +323,5 @@ public class Protocol1_14To1_13_2 extends Protocol {
         userConnection.put(new EntityTracker(userConnection));
         if (!userConnection.has(ClientWorld.class))
             userConnection.put(new ClientWorld(userConnection));
-
     }
 }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_14to1_13_2/data/MappingData.java

@@ -11,11 +11,7 @@ import us.myles.ViaVersion.util.GsonUtil;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
-import java.util.Arrays;
+import java.util.*;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Set;
 
 public class MappingData {
     public static BiMap<Integer, Integer> oldToNewItems = HashBiMap.create();
@@ -23,6 +19,7 @@ public class MappingData {
     public static BlockMappings blockMappings;
     public static SoundMappings soundMappings;
     public static Set<Integer> motionBlocking;
+    public static Set<Integer> nonFullBlocks;
 
     public static void init() {
         JsonObject mapping1_13_2 = loadData("mapping-1.13.2.json");
@@ -57,6 +54,19 @@ public class MappingData {
                 MappingData.motionBlocking.add(id);
             }
         }
+
+        if (Via.getConfig().isNonFullBlockLightFix()) {
+            nonFullBlocks = new HashSet<>();
+            for (Map.Entry<String, JsonElement> blockstates : mapping1_13_2.getAsJsonObject("blockstates").entrySet()) {
+                final String state = blockstates.getValue().getAsString();
+                if (state.contains("_slab") || state.contains("_stairs") || state.contains("_wall["))
+                    nonFullBlocks.add(blockStateMappings.getNewBlock(Integer.parseInt(blockstates.getKey())));
+            }
+            nonFullBlocks.add(blockStateMappings.getNewBlock(8163)); // grass path
+            for (int i = 3060; i <= 3067; i++) { // farmland
+                nonFullBlocks.add(blockStateMappings.getNewBlock(i));
+            }
+        }
     }
 
     public static JsonObject loadData(String name) {

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_14to1_13_2/packets/WorldPackets.java

@@ -4,10 +4,14 @@ import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
 import com.github.steveice10.opennbt.tag.builtin.LongArrayTag;
 import com.google.common.primitives.Bytes;
 import us.myles.ViaVersion.api.PacketWrapper;
+import us.myles.ViaVersion.api.Via;
+import us.myles.ViaVersion.api.data.UserConnection;
 import us.myles.ViaVersion.api.entities.Entity1_14Types;
 import us.myles.ViaVersion.api.minecraft.BlockChangeRecord;
+import us.myles.ViaVersion.api.minecraft.BlockFace;
 import us.myles.ViaVersion.api.minecraft.chunks.Chunk;
 import us.myles.ViaVersion.api.minecraft.chunks.ChunkSection;
+import us.myles.ViaVersion.api.minecraft.chunks.NibbleArray;
 import us.myles.ViaVersion.api.protocol.Protocol;
 import us.myles.ViaVersion.api.remapper.PacketHandler;
 import us.myles.ViaVersion.api.remapper.PacketRemapper;
@@ -164,6 +168,7 @@ public class WorldPackets {
                         for (int s = 0; s < 16; s++) {
                             ChunkSection section = chunk.getSections()[s];
                             if (section == null) continue;
+
                             boolean hasBlock = false;
                             for (int i = 0; i < section.getPaletteSize(); i++) {
                                 int old = section.getPaletteEntry(i);
@@ -177,6 +182,7 @@ public class WorldPackets {
                                 section.setNonAirBlocksCount(0);
                                 continue;
                             }
+
                             int nonAirBlockCount = 0;
                             for (int x = 0; x < 16; x++) {
                                 for (int y = 0; y < 16; y++) {
@@ -189,9 +195,15 @@ public class WorldPackets {
                                         if (MappingData.motionBlocking.contains(id)) {
                                             motionBlocking[x + z * 16] = y + s * 16 + 2; // Should be +1 (top of the block) but +2 works :tm:
                                         }
+
+                                        // Manually update light for non full blocks (block light must not be sent)
+                                        if (Via.getConfig().isNonFullBlockLightFix() && MappingData.nonFullBlocks.contains(id)) {
+                                            setNonFullLight(chunk, section, s, x, y, z);
                                         }
                                     }
                                 }
+                            }
+
                             section.setNonAirBlocksCount(nonAirBlockCount);
                         }
 
@@ -437,4 +449,81 @@ public class WorldPackets {
 
         return data;
     }
+
+    private static void setNonFullLight(Chunk chunk, ChunkSection section, int ySection, int x, int y, int z) {
+        int skyLight = 0;
+        int blockLight = 0;
+        for (BlockFace blockFace : BlockFace.values()) {
+            NibbleArray skyLightArray = section.getSkyLightNibbleArray();
+            NibbleArray blockLightArray = section.getBlockLightNibbleArray();
+            int neighbourX = x + blockFace.getModX();
+            int neighbourY = y + blockFace.getModY();
+            int neighbourZ = z + blockFace.getModZ();
+
+            if (blockFace.getModX() != 0) {
+                // Another chunk, nothing we can do without an unnecessary amount of caching
+                if (neighbourX == 16 || neighbourX == -1) continue;
+            } else if (blockFace.getModY() != 0) {
+                if (neighbourY == 16 || neighbourY == -1) {
+                    if (neighbourY == 16) {
+                        ySection += 1;
+                        neighbourY = 0;
+                    } else {
+                        ySection -= 1;
+                        neighbourY = 15;
+                    }
+
+                    if (ySection == 16 || ySection == -1) continue;
+
+                    ChunkSection newSection = chunk.getSections()[ySection];
+                    if (newSection == null) continue;
+
+                    skyLightArray = newSection.getSkyLightNibbleArray();
+                    blockLightArray = newSection.getBlockLightNibbleArray();
+                }
+            } else if (blockFace.getModZ() != 0) {
+                // Another chunk, nothing we can do without an unnecessary amount of caching
+                if (neighbourZ == 16 || neighbourZ == -1) continue;
+            }
+
+            if (blockLightArray != null && blockLight != 15) {
+                int neighbourBlockLight = blockLightArray.get(neighbourX, neighbourY, neighbourZ);
+                if (neighbourBlockLight == 15) {
+                    blockLight = 14;
+                } else if (neighbourBlockLight > blockLight) {
+                    blockLight = neighbourBlockLight - 1; // lower light level by one
+                }
+            }
+            if (skyLightArray != null && skyLight != 15) {
+                int neighbourSkyLight = skyLightArray.get(neighbourX, neighbourY, neighbourZ);
+                if (neighbourSkyLight == 15) {
+                    if (blockFace.getModY() == 1) {
+                        // Keep 15 if block is exposed to sky
+                        skyLight = 15;
+                        continue;
+                    }
+
+                    skyLight = 14;
+                } else if (neighbourSkyLight > skyLight) {
+                    skyLight = neighbourSkyLight - 1; // lower light level by one
+                }
+            }
+        }
+
+        if (skyLight != 0) {
+            if (!section.hasSkyLight()) {
+                byte[] newSkyLight = new byte[2028];
+                section.setSkyLight(newSkyLight);
+            }
+
+            section.getSkyLightNibbleArray().set(x, y, z, skyLight);
+        }
+        if (blockLight != 0) {
+            section.getBlockLightNibbleArray().set(x, y, z, blockLight);
+        }
+    }
+
+    private static long getChunkIndex(int x, int z) {
+        return ((x & 0x3FFFFFFL) << 38) | (z & 0x3FFFFFFL);
+    }
 }

common/src/main/resources/assets/viaversion/config.yml

@@ -126,6 +126,8 @@ change-1_9-hitbox: false
 # WARNING: This gives 1.14+ players the ability to sneak under blocks, that players under that version cannot (sneaking in places that are only 1.5 blocks high)!
 # Another thing to remember is that those players might be missed by projectiles and other hits directed at the very top of their head whilst sneaking.
 change-1_14-hitbox: false
+# Fixes 1.14+ clients on sub 1.14 servers having a light value of 0 for non full blocks.
+fix-non-full-blocklight: true
 #
 # Enable serverside block-connections for 1.13+ clients
 serverside-blockconnections: false

sponge/src/main/java/us/myles/ViaVersion/sponge/platform/SpongeViaConfig.java

@@ -275,4 +275,9 @@ public class SpongeViaConfig extends Config implements ViaVersionConfig {
     public boolean is1_14HitboxFix() {
         return false;
     }
+
+    @Override
+    public boolean isNonFullBlockLightFix() {
+        return getBoolean("fix-non-full-blocklight", true);
+    }
 }

velocity/src/main/java/us/myles/ViaVersion/velocity/platform/VelocityViaConfig.java

@@ -328,4 +328,9 @@ public class VelocityViaConfig extends Config implements ViaVersionConfig {
     public boolean is1_14HitboxFix() {
         return false;
     }
+
+    @Override
+    public boolean isNonFullBlockLightFix() {
+        return getBoolean("fix-non-full-blocklight", true);
+    }
 }