Wait until navmesh is generated within given distance around player

Add a setting to change this distance.

To prevent situations when there is not enough navmesh generated and actors
can't find path correctly.

CHANGELOG.md

@@ -141,6 +141,7 @@
     Feature #5456: Basic collada animation support
     Feature #5457: Realistic diagonal movement
     Feature #5486: Fixes trainers to choose their training skills based on their base skill points
+    Feature #5500: Prepare enough navmesh tiles before scene loading ends
     Feature #5511: Add in game option to toggle HRTF support in OpenMW
     Feature #5519: Code Patch tab in launcher
     Feature #5524: Resume failed script execution after reload

apps/openmw/mwworld/scene.cpp

@@ -620,6 +620,8 @@ namespace MWWorld
 
         if (changeEvent)
             mCellChanged = true;
+
+        mNavigator.wait(*loadingListener);
     }
 
     void Scene::testExteriorCells()

apps/openmw_test_suite/detournavigator/navigator.cpp

@@ -66,6 +66,7 @@ namespace
             mSettings.mRegionMergeSize = 20;
             mSettings.mRegionMinSize = 8;
             mSettings.mTileSize = 64;
+            mSettings.mWaitUntilMinDistanceToPlayer = std::numeric_limits<int>::max();
             mSettings.mAsyncNavMeshUpdaterThreads = 1;
             mSettings.mMaxNavMeshTilesCacheSize = 1024 * 1024;
             mSettings.mMaxPolygonPathSize = 1024;

components/detournavigator/asyncnavmeshupdater.cpp

@@ -21,6 +21,16 @@ namespace
     {
         return std::abs(lhs.x() - rhs.x()) + std::abs(lhs.y() - rhs.y());
     }
+
+    int getMinDistanceTo(const TilePosition& position, int maxDistance,
+                         const std::map<osg::Vec3f, std::set<TilePosition>>& tilesPerHalfExtents)
+    {
+        int result = maxDistance;
+        for (const auto& [halfExtents, tiles] : tilesPerHalfExtents)
+            for (const TilePosition& tile : tiles)
+                result = std::min(result, getManhattanDistance(position, tile));
+        return result;
+    }
 }
 
 namespace DetourNavigator
@@ -114,24 +124,40 @@ namespace DetourNavigator
 
     void AsyncNavMeshUpdater::wait(Loading::Listener& listener)
     {
+        if (mSettings.get().mWaitUntilMinDistanceToPlayer == 0)
+            return;
         listener.setLabel("Building navigation mesh");
         const std::size_t initialJobsLeft = getTotalJobs();
         std::size_t maxProgress = initialJobsLeft + mThreads.size();
         listener.setProgressRange(maxProgress);
-        waitUntilJobsDone(initialJobsLeft, maxProgress, listener);
+        const int minDistanceToPlayer = waitUntilJobsDone(initialJobsLeft, maxProgress, listener);
+        if (minDistanceToPlayer < mSettings.get().mWaitUntilMinDistanceToPlayer)
+        {
             mProcessingTiles.wait(mProcessed, [] (const auto& v) { return v.empty(); });
             listener.setProgress(maxProgress);
         }
+    }
 
-    void AsyncNavMeshUpdater::waitUntilJobsDone(const std::size_t initialJobsLeft, std::size_t& maxProgress, Loading::Listener& listener)
+    int AsyncNavMeshUpdater::waitUntilJobsDone(const std::size_t initialJobsLeft, std::size_t& maxProgress, Loading::Listener& listener)
     {
         std::size_t prevJobsLeft = initialJobsLeft;
         std::size_t jobsDone = 0;
         std::size_t jobsLeft = 0;
+        const int maxDistanceToPlayer = mSettings.get().mWaitUntilMinDistanceToPlayer;
+        const TilePosition playerPosition = *mPlayerTile.lockConst();
+        int minDistanceToPlayer = 0;
         const auto isDone = [&]
         {
             jobsLeft = mJobs.size() + getTotalThreadJobsUnsafe();
-            return jobsLeft == 0;
+            if (jobsLeft == 0)
+            {
+                minDistanceToPlayer = 0;
+                return true;
+            }
+            minDistanceToPlayer = getMinDistanceTo(playerPosition, maxDistanceToPlayer, mPushed);
+            for (const auto& [threadId, queue] : mThreadsQueues)
+                minDistanceToPlayer = getMinDistanceTo(playerPosition, minDistanceToPlayer, queue.mPushed);
+            return minDistanceToPlayer >= maxDistanceToPlayer;
         };
         std::unique_lock<std::mutex> lock(mMutex);
         while (!mDone.wait_for(lock, std::chrono::milliseconds(250), isDone))
@@ -150,6 +176,7 @@ namespace DetourNavigator
                 listener.increaseProgress(newJobsDone);
             }
         }
+        return minDistanceToPlayer;
     }
 
     void AsyncNavMeshUpdater::reportStats(unsigned int frameNumber, osg::Stats& stats) const

components/detournavigator/asyncnavmeshupdater.hpp

@@ -142,7 +142,7 @@ namespace DetourNavigator
 
         void cleanupLastUpdates();
 
-        void waitUntilJobsDone(const std::size_t initialJobsLeft, std::size_t& maxJobsLeft, Loading::Listener& listener);
+        int waitUntilJobsDone(const std::size_t initialJobsLeft, std::size_t& maxJobsLeft, Loading::Listener& listener);
     };
 }
 

components/detournavigator/settings.cpp

@@ -29,6 +29,7 @@ namespace DetourNavigator
         navigatorSettings.mRegionMergeSize = ::Settings::Manager::getInt("region merge size", "Navigator");
         navigatorSettings.mRegionMinSize = ::Settings::Manager::getInt("region min size", "Navigator");
         navigatorSettings.mTileSize = ::Settings::Manager::getInt("tile size", "Navigator");
+        navigatorSettings.mWaitUntilMinDistanceToPlayer = ::Settings::Manager::getInt("wait until min distance to player", "Navigator");
         navigatorSettings.mAsyncNavMeshUpdaterThreads = static_cast<std::size_t>(::Settings::Manager::getInt("async nav mesh updater threads", "Navigator"));
         navigatorSettings.mMaxNavMeshTilesCacheSize = static_cast<std::size_t>(::Settings::Manager::getInt("max nav mesh tiles cache size", "Navigator"));
         navigatorSettings.mMaxPolygonPathSize = static_cast<std::size_t>(::Settings::Manager::getInt("max polygon path size", "Navigator"));

components/detournavigator/settings.hpp

@@ -31,6 +31,7 @@ namespace DetourNavigator
         int mRegionMergeSize = 0;
         int mRegionMinSize = 0;
         int mTileSize = 0;
+        int mWaitUntilMinDistanceToPlayer = 0;
         std::size_t mAsyncNavMeshUpdaterThreads = 0;
         std::size_t mMaxNavMeshTilesCacheSize = 0;
         std::size_t mMaxPolygonPathSize = 0;

docs/source/reference/modding/settings/navigator.rst

@@ -42,6 +42,18 @@ Increasing this value may decrease performance.
     This condition is always true: ``max tiles number * max polygons per tile <= 4194304``.
     It's a limitation of `Recastnavigation <https://github.com/recastnavigation/recastnavigation>`_ library.
 
+wait until min distance to player
+------------------------------
+
+:Type:		integer
+:Range:		>= 0
+:Default:	5
+
+Distance in navmesh tiles around the player to keep loading screen until navigation mesh is generated.
+Allows to complete cell loading only when minimal navigation mesh area is generated to correctly find path for actors
+nearby the player. Increasing this value will keep loading screen longer but will slightly increase nav mesh generation
+speed on systems bound by CPU. Zero means no waiting.
+
 Advanced settings
 *****************
 

files/settings-default.cfg

@@ -908,6 +908,10 @@ max tiles number = 512
 # Min time duration for the same tile update in milliseconds (value >= 0)
 min update interval ms = 250
 
+# Keep loading screen until navmesh is generated around the player for all tiles within manhattan distance (value >= 0).
+# Distance is measured in the number of tiles and can be only an integer value.
+wait until min distance to player = 5
+
 [Shadows]
 
 # Enable or disable shadows. Bear in mind that this will force OpenMW to use shaders as if "[Shaders]/force shaders" was set to true.