Do not initialize map every call

CHANGELOG.md

@@ -138,6 +138,7 @@
     Task #4605: Optimize skinning
     Task #4606: Support Rapture3D's OpenAL driver
     Task #4613: Incomplete type errors when compiling with g++ on OSX 10.9
+    Task #4621: Optimize combat AI
 
 0.44.0
 ------

components/esm/loadmgef.cpp

@@ -274,7 +274,9 @@ short MagicEffect::getResistanceEffect(short effect)
     // Source https://wiki.openmw.org/index.php?title=Research:Magic#Effect_attribute
 
     // <Effect, Effect providing resistance against first effect>
-    std::map<short, short> effects;
+    static std::map<short, short> effects;
+    if (effects.empty())
+    {
         effects[DisintegrateArmor] = Sanctuary;
         effects[DisintegrateWeapon] = Sanctuary;
 
@@ -310,6 +312,7 @@ short MagicEffect::getResistanceEffect(short effect)
         effects[Corprus] = ResistCorprusDisease;
         effects[Poison] = ResistPoison;
         effects[Paralyze] = ResistParalysis;
+    }
 
     if (effects.find(effect) != effects.end())
         return effects[effect];
@@ -319,8 +322,9 @@ short MagicEffect::getResistanceEffect(short effect)
 
 short MagicEffect::getWeaknessEffect(short effect)
 {
-    std::map<short, short> effects;
+    static std::map<short, short> effects;
-
+    if (effects.empty())
+    {
         for (int i=0; i<5; ++i)
             effects[DrainAttribute+i] = WeaknessToMagicka;
         for (int i=0; i<5; ++i)
@@ -354,6 +358,7 @@ short MagicEffect::getWeaknessEffect(short effect)
         effects[Poison] = WeaknessToPoison;
 
         effects[Paralyze] = -1;
+    }
 
     if (effects.find(effect) != effects.end())
         return effects[effect];