From 26a685187e321040fd85c6eb71d34ec18377d1ca Mon Sep 17 00:00:00 2001
From: Kelsi <kelsihates2fa@gmail.com>
Date: Wed, 25 Feb 2026 13:37:09 -0800
Subject: [PATCH] Fix /logout hang caused by blocking worker thread joins
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unloadAll() joins worker threads which blocks if they're mid-tile
(prepareTile can take seconds for heavy ADTs). Replace with softReset()
which clears tile data, queues, and water surfaces without stopping
worker threads — workers find empty queues and idle naturally.
---
 include/rendering/terrain_manager.hpp |  1 +
 src/core/application.cpp              |  5 +++--
 src/rendering/terrain_manager.cpp     | 26 ++++++++++++++++++++++++++
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/include/rendering/terrain_manager.hpp b/include/rendering/terrain_manager.hpp
index da99ed53..ee06eb30 100644
--- a/include/rendering/terrain_manager.hpp
+++ b/include/rendering/terrain_manager.hpp
@@ -212,6 +212,7 @@ public:
      * Unload all tiles
      */
     void unloadAll();
+    void softReset();  // Clear tile data without stopping worker threads (non-blocking)
 
     /**
      * Precache a set of tiles (for taxi routes, etc.)
diff --git a/src/core/application.cpp b/src/core/application.cpp
index e7d7f656..994813c6 100644
--- a/src/core/application.cpp
+++ b/src/core/application.cpp
@@ -661,9 +661,10 @@ void Application::logoutToLogin() {
         if (auto* m2 = renderer->getM2Renderer()) {
             m2->clear();
         }
-        // Unload all terrain tiles + water surfaces so next world entry starts fresh
+        // Clear terrain tile tracking + water surfaces so next world entry starts fresh.
+        // Use softReset() instead of unloadAll() to avoid blocking on worker thread joins.
         if (auto* terrain = renderer->getTerrainManager()) {
-            terrain->unloadAll();
+            terrain->softReset();
         }
         if (auto* questMarkers = renderer->getQuestMarkerRenderer()) {
             questMarkers->clear();
diff --git a/src/rendering/terrain_manager.cpp b/src/rendering/terrain_manager.cpp
index afd50824..3554b3d3 100644
--- a/src/rendering/terrain_manager.cpp
+++ b/src/rendering/terrain_manager.cpp
@@ -1296,6 +1296,32 @@ void TerrainManager::unloadAll() {
     }
 }
 
+void TerrainManager::softReset() {
+    // Clear queues (workers may still be running — they'll find empty queues)
+    {
+        std::lock_guard<std::mutex> lock(queueMutex);
+        loadQueue.clear();
+        while (!readyQueue.empty()) readyQueue.pop();
+    }
+    pendingTiles.clear();
+    finalizingTiles_.clear();
+    placedDoodadIds.clear();
+
+    LOG_INFO("Soft-resetting terrain (clearing tiles + water, workers stay alive)");
+    loadedTiles.clear();
+    failedTiles.clear();
+
+    currentTile = {-1, -1};
+    lastStreamTile = {-1, -1};
+
+    if (terrainRenderer) {
+        terrainRenderer->clear();
+    }
+    if (waterRenderer) {
+        waterRenderer->clear();
+    }
+}
+
 TileCoord TerrainManager::worldToTile(float glX, float glY) const {
     auto [tileX, tileY] = core::coords::worldToTile(glX, glY);
     return {tileX, tileY};