Ticket #4191: 0003-Make-AI-map-updates-more-clever.patch

source/simulation2/components/CCmpAIManager.cpp

@@ -520 +520 @@
         ENSURE(m_CommandsComputed);
 
         m_GameState = gameState;
-        JSContext* cx = m_ScriptInterface->GetContext();
 
         if (dirtinessInformations.dirty)
         {
+            bool dimensionChange = m_PassabilityMap.m_W != passabilityMap.m_W || m_PassabilityMap.m_H != passabilityMap.m_H;
+
             m_PassabilityMap = passabilityMap;
             if (dirtinessInformations.globallyDirty)
                 m_LongPathfinder.Reload(&m_PassabilityMap, nonPathfindingPassClassMasks, pathfindingPassClassMasks);
             else
                 m_LongPathfinder.Update(&m_PassabilityMap, dirtinessInformations.dirtinessGrid);
-            ScriptInterface::ToJSVal(cx, &m_PassabilityMapVal, m_PassabilityMap);
+
+            if (dimensionChange)
+            {
+                JSContext* cx = m_ScriptInterface->GetContext();
+                ScriptInterface::ToJSVal(cx, &m_PassabilityMapVal, m_PassabilityMap);
+            }
+            else
+                UpdatePassabilityMapVal();
         }
 
         if (territoryMapDirty)
         {
+            bool dimensionChange = m_TerritoryMap.m_W != territoryMap.m_W || m_TerritoryMap.m_H != territoryMap.m_H;
+
             m_TerritoryMap = territoryMap;
-            ScriptInterface::ToJSVal(cx, &m_TerritoryMapVal, m_TerritoryMap);
+
+            if (dimensionChange)
+            {
+                JSContext* cx = m_ScriptInterface->GetContext();
+                ScriptInterface::ToJSVal(cx, &m_TerritoryMapVal, m_TerritoryMap);
+            }
+            else
+                UpdateTerritoryMapVal();
         }
 
         m_CommandsComputed = false;
     }
 
+    // Those functions are used to avoid an useless memory reallocation followed by a garbage collection on each turn.
+    // Warning: They assume the maps do not change dimensions. Only the raw data of the maps will be updated.
+    // Additionally, a segmentation fault would happen if the map dimensions are reduced.
+
+    void UpdatePassabilityMapVal()
+    {
+        JSContext* cx = m_ScriptInterface->GetContext();
+        JSAutoRequest rq(cx);
+
+        JS::RootedObject mapObj(cx, &m_PassabilityMapVal.toObject());
+        JS::RootedValue mapData(cx);
+        ENSURE(JS_GetProperty(cx, mapObj, "data", &mapData));
+        JS::RootedObject dataObj(cx, &mapData.toObject());
+
+        u32 length = 0;
+        ENSURE(JS_GetArrayLength(cx, dataObj, &length));
+        u32 nbytes = (u32)(length * sizeof(NavcellData));
+
+        JS::AutoCheckCannotGC nogc;
+        memcpy((void*)JS_GetUint16ArrayData(dataObj, nogc), m_PassabilityMap.m_Data, nbytes);
+    }
+    void UpdateTerritoryMapVal()
+    {
+        JSContext* cx = m_ScriptInterface->GetContext();
+        JSAutoRequest rq(cx);
+
+        JS::RootedObject mapObj(cx, &m_TerritoryMapVal.toObject());
+        JS::RootedValue mapData(cx);
+        ENSURE(JS_GetProperty(cx, mapObj, "data", &mapData));
+        JS::RootedObject dataObj(cx, &mapData.toObject());
+
+        u32 length = 0;
+        ENSURE(JS_GetArrayLength(cx, dataObj, &length));
+        u32 nbytes = (u32)(length * sizeof(u8));
+
+        JS::AutoCheckCannotGC nogc;
+        memcpy((void*)JS_GetUint8ArrayData(dataObj, nogc), m_TerritoryMap.m_Data, nbytes);
+    }
+
     void WaitToFinishComputation()
     {
         if (!m_CommandsComputed)