diff --git a/lib/mapObjects/ObjectTemplate.cpp b/lib/mapObjects/ObjectTemplate.cpp
index 7dcd1d799..153d2d3e4 100644
--- a/lib/mapObjects/ObjectTemplate.cpp
+++ b/lib/mapObjects/ObjectTemplate.cpp
@@ -350,7 +350,7 @@ ui32 ObjectTemplate::getWidth() const
 	//TODO: Use 2D array
 	//TODO: better precalculate and store constant value
 	ui32 ret = 0;
-	for (auto const &row : usedTiles) //copy is expensive
+	for (const auto &row : usedTiles) //copy is expensive
 	{
 		ret = std::max<ui32>(ret, row.size());
 	}
diff --git a/lib/mapping/CMapEditManager.cpp b/lib/mapping/CMapEditManager.cpp
index 95b7b8fbb..87439613d 100644
--- a/lib/mapping/CMapEditManager.cpp
+++ b/lib/mapping/CMapEditManager.cpp
@@ -321,16 +321,16 @@ TerrainViewPattern::TerrainViewPattern() : diffImages(false), rotationTypesCount
 	maxPoints = std::numeric_limits<int>::max();
 }
 
-TerrainViewPattern::WeightedRule::WeightedRule() : points(0)
+TerrainViewPattern::WeightedRule::WeightedRule(std::string &Name) : points(0), name(Name)
 {
-
+	standardRule = (TerrainViewPattern::RULE_ANY == name || TerrainViewPattern::RULE_DIRT == name
+		|| TerrainViewPattern::RULE_NATIVE == name || TerrainViewPattern::RULE_SAND == name
+		|| TerrainViewPattern::RULE_TRANSITION == name || TerrainViewPattern::RULE_NATIVE_STRONG == name);
 }
 
 bool TerrainViewPattern::WeightedRule::isStandardRule() const
 {
-	return TerrainViewPattern::RULE_ANY == name || TerrainViewPattern::RULE_DIRT == name
-		|| TerrainViewPattern::RULE_NATIVE == name || TerrainViewPattern::RULE_SAND == name
-		|| TerrainViewPattern::RULE_TRANSITION == name || TerrainViewPattern::RULE_NATIVE_STRONG == name;
+	return standardRule;
 }
 
 CTerrainViewPatternConfig::CTerrainViewPatternConfig()
@@ -357,8 +357,7 @@ CTerrainViewPatternConfig::CTerrainViewPatternConfig()
 				{
 					std::vector<std::string> ruleParts;
 					boost::split(ruleParts, ruleStr, boost::is_any_of("-"));
-					TerrainViewPattern::WeightedRule rule;
-					rule.name = ruleParts[0];
+					TerrainViewPattern::WeightedRule rule(ruleParts[0]);
 					assert(!rule.name.empty());
 					if(ruleParts.size() > 1)
 					{
diff --git a/lib/mapping/CMapEditManager.h b/lib/mapping/CMapEditManager.h
index b24cb9262..a2b91c1b6 100644
--- a/lib/mapping/CMapEditManager.h
+++ b/lib/mapping/CMapEditManager.h
@@ -229,7 +229,7 @@ struct DLL_LINKAGE TerrainViewPattern
 {
 	struct WeightedRule
 	{
-		WeightedRule();
+		WeightedRule(std::string &Name);
 		/// Gets true if this rule is a standard rule which means that it has a value of one of the RULE_* constants.
 		bool isStandardRule() const;
 
@@ -237,6 +237,11 @@ struct DLL_LINKAGE TerrainViewPattern
 		std::string name;
 		/// Optional. A rule can have points. Patterns may have a minimum count of points to reach to be successful.
 		int points;
+
+	private:		
+		bool standardRule;
+
+		WeightedRule(); //only allow string constructor
 	};
 
 	static const int PATTERN_DATA_SIZE = 9;
diff --git a/lib/rmg/CRmgTemplateZone.cpp b/lib/rmg/CRmgTemplateZone.cpp
index 9a655226e..6825beade 100644
--- a/lib/rmg/CRmgTemplateZone.cpp
+++ b/lib/rmg/CRmgTemplateZone.cpp
@@ -1497,11 +1497,7 @@ void CRmgTemplateZone::initTerrainType (CMapGenerator* gen)
 
 void CRmgTemplateZone::paintZoneTerrain (CMapGenerator* gen, ETerrainType terrainType)
 {
-	std::vector<int3> tiles;
-	for (auto tile : tileinfo)
-	{
-		tiles.push_back (tile);
-	}
+	std::vector<int3> tiles(tileinfo.begin(), tileinfo.end());
 	gen->editManager->getTerrainSelection().setSelection(tiles);
 	gen->editManager->drawTerrain(terrainType, &gen->rand);
 }
@@ -2305,7 +2301,6 @@ ObjectInfo CRmgTemplateZone::getRandomObject(CMapGenerator* gen, CTreasurePileIn
 
 			bool fitsBlockmap = true;
 
-
 			std::set<int3> blockedOffsets = oi.templ.getBlockedOffsets();
 			blockedOffsets.insert (newVisitableOffset);
 			for (auto blockingTile : blockedOffsets)
@@ -2327,13 +2322,11 @@ ObjectInfo CRmgTemplateZone::getRandomObject(CMapGenerator* gen, CTreasurePileIn
 
 			total += oi.probability;
 			
-			//FIXME: apparently this is quite expensive operation
+			//FIXME: apparently this is quite expensive operation, but "reserve" doesn't improve speed
 			thresholds.push_back (std::make_pair (total, oi));
 		}
 	}
 
-	//logGlobal->infoStream() << boost::format ("Number of objects visitable  from bottom: %d") % objectsVisitableFromBottom;
-
 	if (thresholds.empty())
 	{
 		ObjectInfo oi;