From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: HaHaWTH <102713261+HaHaWTH@users.noreply.github.com>
Date: Tue, 9 Nov 2077 00:00:00 +0800
Subject: [PATCH] Smooth teleport config

This abuses some of how Minecraft works and attempts to teleport a player to another world without
triggering typical respawn packets. All of natural state of chunk resends, entity adds/removes, etc still
happen but the visual "refresh" of a world change is hidden. Depending on the destination location/world,
this can act as a "smooth teleport" to a world if the new world is very similar looking to the old one.

diff --git a/src/main/java/net/minecraft/server/level/ServerPlayer.java b/src/main/java/net/minecraft/server/level/ServerPlayer.java
index edef689792b163e6a33921fe2e4b1af69715a2ee..28723ab8bd72ff0db5e21c68f44f0a8d96b37653 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayer.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayer.java
@@ -1422,7 +1422,11 @@ public class ServerPlayer extends net.minecraft.world.entity.player.Player imple
                 this.isChangingDimension = true; // CraftBukkit - Set teleport invulnerability only if player changing worlds
                 LevelData worlddata = worldserver.getLevelData();
 
-                this.connection.send(new ClientboundRespawnPacket(this.createCommonSpawnInfo(worldserver), (byte) 3));
+                // Leaf start - Smooth teleport
+                int previousLogicalHeight = worldserver1.getLogicalHeight();
+                int currentLogicalHeight = worldserver.getLogicalHeight();
+                if (!org.dreeam.leaf.config.modules.gameplay.SmoothTeleport.enabled || previousLogicalHeight != currentLogicalHeight) this.connection.send(new ClientboundRespawnPacket(this.createCommonSpawnInfo(worldserver), (byte) 3));
+                // Leaf end - Smooth teleport
                 this.connection.send(new ClientboundChangeDifficultyPacket(worlddata.getDifficulty(), worlddata.isDifficultyLocked()));
                 PlayerList playerlist = this.server.getPlayerList();
 
@@ -1432,7 +1436,7 @@ public class ServerPlayer extends net.minecraft.world.entity.player.Player imple
                 // CraftBukkit end
                 this.portalPos = io.papermc.paper.util.MCUtil.toBlockPosition(exit); // Purpur - Fix stuck in portals
                 this.setServerLevel(worldserver);
-                this.connection.teleport(exit); // CraftBukkit - use internal teleport without event
+                if (!org.dreeam.leaf.config.modules.gameplay.SmoothTeleport.enabled || previousLogicalHeight != currentLogicalHeight) this.connection.teleport(exit); // CraftBukkit - use internal teleport without event // Leaf
                 this.connection.resetPosition();
                 worldserver.addDuringTeleport(this);
                 this.triggerDimensionChangeTriggers(worldserver1);
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index f3b98a4a66cec8d6c9dc46479d573c2fb453837a..00b9d244898ffdc1584eb254643557776bf4a76f 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -1057,10 +1057,10 @@ public abstract class PlayerList {
         ServerLevel worldserver1 = entityplayer1.serverLevel();
         LevelData worlddata = worldserver1.getLevelData();
 
-        if (!entityplayer.smoothWorldTeleport || !isSameLogicalHeight((ServerLevel) fromWorld, worldserver)) entityplayer1.connection.send(new ClientboundRespawnPacket(entityplayer1.createCommonSpawnInfo(worldserver1), (byte) i)); // Slice // Leaf
+        if ((!entityplayer.smoothWorldTeleport && !org.dreeam.leaf.config.modules.gameplay.SmoothTeleport.enabled) || i != 1 || !isSameLogicalHeight((ServerLevel) fromWorld, worldserver)) entityplayer1.connection.send(new ClientboundRespawnPacket(entityplayer1.createCommonSpawnInfo(worldserver1), (byte) i)); // Slice // Leaf
         entityplayer1.connection.send(new ClientboundSetChunkCacheRadiusPacket(worldserver1.spigotConfig.viewDistance)); // Spigot
         entityplayer1.connection.send(new ClientboundSetSimulationDistancePacket(worldserver1.spigotConfig.simulationDistance)); // Spigot
-        if (!entityplayer.smoothWorldTeleport || !isSameLogicalHeight((ServerLevel) fromWorld, worldserver)) entityplayer1.connection.teleport(CraftLocation.toBukkit(entityplayer1.position(), worldserver1.getWorld(), entityplayer1.getYRot(), entityplayer1.getXRot())); // CraftBukkit // Slice // Leaf
+        if ((!entityplayer.smoothWorldTeleport && !org.dreeam.leaf.config.modules.gameplay.SmoothTeleport.enabled) || i != 1 || !isSameLogicalHeight((ServerLevel) fromWorld, worldserver)) entityplayer1.connection.teleport(CraftLocation.toBukkit(entityplayer1.position(), worldserver1.getWorld(), entityplayer1.getYRot(), entityplayer1.getXRot())); // CraftBukkit // Slice // Leaf
         entityplayer1.connection.send(new ClientboundSetDefaultSpawnPositionPacket(worldserver.getSharedSpawnPos(), worldserver.getSharedSpawnAngle()));
         entityplayer1.connection.send(new ClientboundChangeDifficultyPacket(worlddata.getDifficulty(), worlddata.isDifficultyLocked()));
         entityplayer1.connection.send(new ClientboundSetExperiencePacket(entityplayer1.experienceProgress, entityplayer1.totalExperience, entityplayer1.experienceLevel));
diff --git a/src/main/java/org/dreeam/leaf/config/modules/gameplay/SmoothTeleport.java b/src/main/java/org/dreeam/leaf/config/modules/gameplay/SmoothTeleport.java
new file mode 100644
index 0000000000000000000000000000000000000000..5fd8923efb2f8369d990767d40d75c004ceb7a1b
--- /dev/null
+++ b/src/main/java/org/dreeam/leaf/config/modules/gameplay/SmoothTeleport.java
@@ -0,0 +1,27 @@
+package org.dreeam.leaf.config.modules.gameplay;
+
+import org.dreeam.leaf.config.ConfigModules;
+import org.dreeam.leaf.config.EnumConfigCategory;
+
+public class SmoothTeleport extends ConfigModules {
+
+    public String getBasePath() {
+        return EnumConfigCategory.GAMEPLAY.getBaseKeyName() + ".smooth-teleport";
+    }
+
+    public static boolean enabled = false;
+
+    @Override
+    public void onLoaded() {
+        enabled = config.getBoolean(getBasePath(), enabled, config.pickStringRegionBased(
+                """
+                        **Experimental feature, report any bugs you encounter!**
+                        Whether to make a "smooth teleport" when players changing dimension.
+                        This requires original world and target world have same logical height to work.""",
+                """
+                        **实验性功能, 请及时反馈你遇到的问题!**
+                        是否在玩家切换世界时尝试使用 "平滑传送".
+                        此项要求源世界和目标世界逻辑高度相同才会生效."""
+        ));
+    }
+}