From c96673989ca8d4729ca5deaaed1c179d6ff93c9b Mon Sep 17 00:00:00 2001
From: Player Name <none>
Date: Sun, 28 Jun 2026 01:01:27 +0200
Subject: [PATCH] Fix POH flashing correctly

---
 Server/src/main/core/game/node/entity/player/Player.java  | 5 +++++
 .../src/main/core/game/world/update/MapChunkRenderer.kt   | 8 ++------
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/Server/src/main/core/game/node/entity/player/Player.java b/Server/src/main/core/game/node/entity/player/Player.java
index cb94a83bd..ea08ea6bf 100644
--- a/Server/src/main/core/game/node/entity/player/Player.java
+++ b/Server/src/main/core/game/node/entity/player/Player.java
@@ -545,6 +545,11 @@ public class Player extends Entity {
 		super.update();
 		if (playerFlags.isUpdateSceneGraph()) {
 			updateSceneGraph(false);
+			// The scene graph rebuild wipes the client's build area. Reset lastViewport so MapChunkRenderer
+			// re-synchronizes every visible chunk this tick (restoring scenery immediately and re-sending
+			// each ground item exactly once), rather than only sending incremental updates for overlap.
+			// This fixes POHs flashing their cached states (hotspots) on z transition.
+			playerFlags.setLastViewport(new RegionChunk[13][13]);
 		}
 		PlayerRenderer.render(this);
 		NPCRenderer.render(this);
diff --git a/Server/src/main/core/game/world/update/MapChunkRenderer.kt b/Server/src/main/core/game/world/update/MapChunkRenderer.kt
index 001327a93..8f1b84171 100644
--- a/Server/src/main/core/game/world/update/MapChunkRenderer.kt
+++ b/Server/src/main/core/game/world/update/MapChunkRenderer.kt
@@ -2,7 +2,6 @@ package core.game.world.update
 
 import core.game.node.entity.player.Player
 import core.game.world.map.RegionChunk
-import core.game.world.map.build.DynamicRegion
 import core.net.packet.PacketRepository
 import core.net.packet.context.ClearChunkContext
 import core.net.packet.out.ClearRegionChunk
@@ -41,12 +40,9 @@ object MapChunkRenderer {
                 val previous = last[x][y] ?: continue
                 if (containsChunk(current, previous)) {
                     updated.add(previous)
-                    continue
+                } else {
+                    PacketRepository.send(ClearRegionChunk::class.java, ClearChunkContext(player, previous))
                 }
-                if (previous.region is DynamicRegion) {
-                    continue //dynamic regions do not need a clear packet and briefly flash their cached states (e.g. POH with only hotspots) if you do send one
-                }
-                PacketRepository.send(ClearRegionChunk::class.java, ClearChunkContext(player, previous))
             }
         }
         sizeX = current.size