From b0322fa3e5ff3dd0e777fd460a38e15814547ff2 Mon Sep 17 00:00:00 2001
From: Melledy <52122272+Melledy@users.noreply.github.com>
Date: Mon, 25 Apr 2022 02:16:01 -0700
Subject: [PATCH] Dont deregister scenes if the player is going to tp back into
 them

---
 .../emu/grasscutter/game/GenshinScene.java    | 11 +++++++++-
 src/main/java/emu/grasscutter/game/World.java | 22 ++++++++++++++-----
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/src/main/java/emu/grasscutter/game/GenshinScene.java b/src/main/java/emu/grasscutter/game/GenshinScene.java
index b738e6d26..60d72c9a7 100644
--- a/src/main/java/emu/grasscutter/game/GenshinScene.java
+++ b/src/main/java/emu/grasscutter/game/GenshinScene.java
@@ -47,6 +47,7 @@ public class GenshinScene {
 	
 	private final Set<SpawnDataEntry> spawnedEntities;
 	private final Set<SpawnDataEntry> deadSpawnedEntities;
+	private boolean dontDestroyWhenEmpty;
 	
 	private int time;
 	private ClimateType climate;
@@ -121,6 +122,14 @@ public class GenshinScene {
 		this.weather = weather;
 	}
 
+	public boolean dontDestroyWhenEmpty() {
+		return dontDestroyWhenEmpty;
+	}
+
+	public void setDontDestroyWhenEmpty(boolean dontDestroyWhenEmpty) {
+		this.dontDestroyWhenEmpty = dontDestroyWhenEmpty;
+	}
+
 	public Set<SpawnDataEntry> getSpawnedEntities() {
 		return spawnedEntities;
 	}
@@ -166,7 +175,7 @@ public class GenshinScene {
 		}
 		
 		// Deregister scene if not in use
-		if (this.getEntities().size() <= 0) {
+		if (this.getEntities().size() <= 0 && !this.dontDestroyWhenEmpty()) {
 			this.getWorld().deregisterScene(this);
 		}
 	}
diff --git a/src/main/java/emu/grasscutter/game/World.java b/src/main/java/emu/grasscutter/game/World.java
index ffffb1e53..25cbcd3e5 100644
--- a/src/main/java/emu/grasscutter/game/World.java
+++ b/src/main/java/emu/grasscutter/game/World.java
@@ -212,19 +212,29 @@ public class World implements Iterable<GenshinPlayer> {
 			return false;
 		}
 		
-		Integer oldSceneId = null;
+		GenshinScene oldScene = null;
 
 		if (player.getScene() != null) {
-			oldSceneId = player.getScene().getId();
-			player.getScene().removePlayer(player);
+			oldScene = player.getScene();
+			
+			// Dont deregister scenes if the player is going to tp back into them
+			if (oldScene.getId() == sceneId) {
+				oldScene.setDontDestroyWhenEmpty(true);
+			}
+			
+			oldScene.removePlayer(player);
 		}
 		
-		GenshinScene scene = this.getSceneById(sceneId);
-		scene.addPlayer(player);
+		GenshinScene newScene = this.getSceneById(sceneId);
+		newScene.addPlayer(player);
 		player.getPos().set(pos);
 		
+		if (oldScene != null) {
+			oldScene.setDontDestroyWhenEmpty(false);
+		}
+		
 		// Teleport packet
-		if (oldSceneId.equals(sceneId)) {
+		if (oldScene == newScene) {
 			player.sendPacket(new PacketPlayerEnterSceneNotify(player, EnterType.EnterGoto, EnterReason.TransPoint, sceneId, pos));
 		} else {
 			player.sendPacket(new PacketPlayerEnterSceneNotify(player, EnterType.EnterJump, EnterReason.TransPoint, sceneId, pos));