From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Zach Brown <zach.brown@destroystokyo.com>
Date: Sun, 22 May 2016 20:20:55 -0500
Subject: [PATCH] Optional TNT doesn't move in water


diff --git a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
index 05ea87a473228f5b386258fae3943f3f4561eaa6..ac76bdd7e1d91b0d242539c4495948cdfbb622e0 100644
--- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
@@ -2,7 +2,6 @@ package com.destroystokyo.paper;
 
 import java.util.List;
 
-import org.bukkit.Bukkit;
 import org.bukkit.configuration.file.YamlConfiguration;
 import org.spigotmc.SpigotWorldConfig;
 
@@ -284,4 +283,14 @@ public class PaperWorldConfig {
             );
         }
     }
+
+    public boolean preventTntFromMovingInWater;
+    private void preventTntFromMovingInWater() {
+        if (PaperConfig.version < 13) {
+            boolean oldVal = getBoolean("enable-old-tnt-cannon-behaviors", false);
+            set("prevent-tnt-from-moving-in-water", oldVal);
+        }
+        preventTntFromMovingInWater = getBoolean("prevent-tnt-from-moving-in-water", false);
+        log("Prevent TNT from moving in water: " + preventTntFromMovingInWater);
+    }
 }
diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
index c51a80f4cbbbe355e332581559b357dc6abe66bf..3b3b443cd25ef5c327f54c5e784e03bd81c73a7a 100644
--- a/src/main/java/net/minecraft/server/Entity.java
+++ b/src/main/java/net/minecraft/server/Entity.java
@@ -2664,6 +2664,11 @@ public abstract class Entity implements INamableTileEntity, ICommandListener, Ke
     }
 
     public boolean bU() {
+        // Paper start
+        return this.pushedByWater();
+    }
+    public boolean pushedByWater() {
+        // Paper end
         return true;
     }
 
diff --git a/src/main/java/net/minecraft/server/EntityTNTPrimed.java b/src/main/java/net/minecraft/server/EntityTNTPrimed.java
index 623db6e3befcc7031e68c71f7eb179fce78291c4..3e71332c47000b21ff90aec6937f90dc639a41bd 100644
--- a/src/main/java/net/minecraft/server/EntityTNTPrimed.java
+++ b/src/main/java/net/minecraft/server/EntityTNTPrimed.java
@@ -80,7 +80,27 @@ public class EntityTNTPrimed extends Entity {
                 this.world.addParticle(Particles.SMOKE, this.locX(), this.locY() + 0.5D, this.locZ(), 0.0D, 0.0D, 0.0D);
             }
         }
-
+        // Paper start - Optional prevent TNT from moving in water
+        if (!this.dead && this.inWater && this.world.paperConfig.preventTntFromMovingInWater) {
+            /*
+             * Author: Jedediah Smith <jedediah@silencegreys.com>
+             */
+            // Send position and velocity updates to nearby players on every tick while the TNT is in water.
+            // This does pretty well at keeping their clients in sync with the server.
+            PlayerChunkMap.EntityTracker ete = ((WorldServer)this.world).getChunkProvider().playerChunkMap.trackedEntities.get(this.getId());
+            if (ete != null) {
+                PacketPlayOutEntityVelocity velocityPacket = new PacketPlayOutEntityVelocity(this);
+                PacketPlayOutEntityTeleport positionPacket = new PacketPlayOutEntityTeleport(this);
+
+                ete.trackedPlayers.stream()
+                    .filter(viewer -> (viewer.locX() - this.locX()) * (viewer.locY() - this.locY()) * (viewer.locZ() - this.locZ()) < 16 * 16)
+                    .forEach(viewer -> {
+                        viewer.playerConnection.sendPacket(velocityPacket);
+                        viewer.playerConnection.sendPacket(positionPacket);
+                    });
+            }
+        }
+        // Paper end
     }
 
     private void explode() {
@@ -149,4 +169,11 @@ public class EntityTNTPrimed extends Entity {
     public Packet<?> P() {
         return new PacketPlayOutSpawnEntity(this);
     }
+
+    // Paper start - Optional prevent TNT from moving in water
+    @Override
+    public boolean pushedByWater() {
+        return !world.paperConfig.preventTntFromMovingInWater && super.pushedByWater();
+    }
+    // Paper end
 }
diff --git a/src/main/java/net/minecraft/server/EntityTrackerEntry.java b/src/main/java/net/minecraft/server/EntityTrackerEntry.java
index 50df43653933e3bdeb3fd514a1c6c3b9ac3b15ab..bbb3f88bb15c70aec7f4d223dd3c0cc986c6eb21 100644
--- a/src/main/java/net/minecraft/server/EntityTrackerEntry.java
+++ b/src/main/java/net/minecraft/server/EntityTrackerEntry.java
@@ -38,7 +38,7 @@ public class EntityTrackerEntry {
     private boolean q;
     private boolean r;
     // CraftBukkit start
-    private final Set<EntityPlayer> trackedPlayers;
+    final Set<EntityPlayer> trackedPlayers; // Paper - private -> package
     // Paper start
     private java.util.Map<EntityPlayer, Boolean> trackedPlayerMap = null;