(bugfix): Prevent unnecessary copies with more std::move and emplace (#1870)

* Prevent unnecessary copies of tmp handles in metadata manager

* Add some more missing emplace

* One last emplace

* Optimize HM3D semantic scene a bit

* Fix some more missing std::move

* Add another missing emplace

Author: Skylion007

src/esp/core/Configuration.h

@@ -748,7 +748,7 @@ class Configuration {
    */
   std::shared_ptr<Configuration> addSubgroup(const std::string& name) {
     // Attempt to insert an empty pointer
-    auto result = configMap_.insert({name, std::shared_ptr<Configuration>{}});
+    auto result = configMap_.emplace(name, std::shared_ptr<Configuration>{});
     // If name not already present (insert succeeded) then add new
     // configuration
     if (result.second) {

src/esp/geo/VoxelGrid.cpp

@@ -288,8 +288,8 @@ void VoxelGrid::generateMeshDataAndMeshGL(
   if (meshGLDict_.find(gridName) != meshGLDict_.end()) {
     meshGLDict_[gridName] = Mn::MeshTools::compile(*meshDataDict_[gridName]);
   } else {
-    meshGLDict_.insert(std::make_pair(
-        gridName, Mn::MeshTools::compile(*meshDataDict_[gridName])));
+    meshGLDict_.emplace(gridName,
+                        Mn::MeshTools::compile(*meshDataDict_[gridName]));
   }
 }
 

src/esp/geo/VoxelGrid.h

@@ -130,7 +130,7 @@ class VoxelGrid {
 
     new_grid.view = view;
     new_grid.type = type;
-    grids_.insert(std::make_pair(gridName, std::move(new_grid)));
+    grids_.emplace(gridName, std::move(new_grid));
   }
 
   /**

src/esp/metadata/managers/AssetAttributesManager.cpp

@@ -104,7 +104,7 @@ AssetAttributesManager::AssetAttributesManager()
     auto tmplt = AssetAttributesManager::createObject(elem.second, true);
     std::string tmpltHandle = tmplt->getHandle();
     defaultPrimAttributeHandles_[elem.second] = tmpltHandle;
-    this->undeletableObjectNames_.insert(tmpltHandle);
+    this->undeletableObjectNames_.insert(std::move(tmpltHandle));
   }
 
   ESP_DEBUG() << "Built default primitive asset templates :"

src/esp/metadata/managers/AttributesManagerBase.h

@@ -277,7 +277,7 @@ std::vector<int> AttributesManager<T, Access>::loadAllFileBasedTemplates(
       // save handles in list of defaults, so they are not removed, if desired.
       if (saveAsDefaults) {
         std::string tmpltHandle = tmplt->getHandle();
-        this->undeletableObjectNames_.insert(tmpltHandle);
+        this->undeletableObjectNames_.insert(std::move(tmpltHandle));
       }
       templateIndices[i] = tmplt->getID();
     }

src/esp/metadata/managers/ObjectAttributesManager.cpp

@@ -66,7 +66,7 @@ void ObjectAttributesManager::createDefaultPrimBasedAttributesTemplates() {
     auto tmplt = createPrimBasedAttributesTemplate(elem, true);
     // save handles in list of defaults, so they are not removed
     std::string tmpltHandle = tmplt->getHandle();
-    this->undeletableObjectNames_.insert(tmpltHandle);
+    this->undeletableObjectNames_.insert(std::move(tmpltHandle));
   }
 }  // ObjectAttributesManager::createDefaultPrimBasedAttributesTemplates
 

src/esp/metadata/managers/StageAttributesManager.cpp

@@ -41,7 +41,7 @@ StageAttributesManager::StageAttributesManager(
   auto tmplt = this->postCreateRegister(
       StageAttributesManager::initNewObjectInternal("NONE", false), true);
   std::string tmpltHandle = tmplt->getHandle();
-  this->undeletableObjectNames_.insert(tmpltHandle);
+  this->undeletableObjectNames_.insert(std::move(tmpltHandle));
 }  // StageAttributesManager::ctor
 
 int StageAttributesManager::registerObjectFinalize(

src/esp/scene/HM3DSemanticScene.cpp

@@ -76,15 +76,15 @@ void buildInstanceRegionCategory(
       instanceID, 0, objCategoryName,
       Cr::Utility::formatString("{}_{}", objCategoryName, instanceID),
       colorInt};
-  objInstance[instanceID] = obj;
+  objInstance[instanceID] = std::move(obj);
   // find category, build if dne
   TempHM3DCategory tmpCat{
       static_cast<int>(categories.size()), objCategoryName, {}};
-  auto categoryIter = categories.emplace(objCategoryName, tmpCat);
+  auto categoryIter = categories.emplace(objCategoryName, std::move(tmpCat));
   categoryIter.first->second.objInstances.push_back(&objInstance[instanceID]);
   // find region, build if dne
   TempHM3DRegion tmpRegion{regionID, {}};
-  auto regionIter = regions.emplace(regionID, tmpRegion);
+  auto regionIter = regions.emplace(regionID, std::move(tmpRegion));
   regionIter.first->second.objInstances.push_back(&objInstance[instanceID]);
 }  // buildInstanceRegionCategory
 
@@ -133,7 +133,7 @@ bool SemanticScene::buildHM3DHouse(std::ifstream& ifs,
                               uint8_t((colorInt >> 8) & 0xff),
                               uint8_t(colorInt & 0xff)};
     // object category will possibly have commas
-    const std::string objCategoryName = tokens[1];
+    const std::string& objCategoryName = tokens[1];
     // room/region is always last token - get rid of first comma
     int regionID =
         std::stoi(Cr::Utility::String::trim(tokens[tokens.size() - 1], " ,"));
@@ -173,7 +173,7 @@ bool SemanticScene::buildHM3DHouse(std::ifstream& ifs,
     for (TempHM3DObject* objItem : regionItem.second.objInstances) {
       objItem->region = regionPtr;
     }
-    scene.regions_.emplace_back(regionPtr);
+    scene.regions_.emplace_back(std::move(regionPtr));
   }
 
   // build all object instances
@@ -188,8 +188,8 @@ bool SemanticScene::buildHM3DHouse(std::ifstream& ifs,
     // set region
     objPtr->parentIndex_ = obj.region->index_;
     objPtr->region_ = obj.region;
-    objPtr->region_->objects_.push_back(objPtr);
-    scene.objects_.emplace_back(objPtr);
+    objPtr->region_->objects_.emplace_back(objPtr);
+    scene.objects_.emplace_back(std::move(objPtr));
   }
   scene.hasVertColors_ = true;
 

src/esp/scene/SemanticScene.cpp

@@ -182,7 +182,7 @@ SemanticScene::buildCCBasedSemanticObjs(
   std::unordered_map<uint32_t, uint32_t> mapColorIntsToSemanticObjIDXs;
   mapColorIntsToSemanticObjIDXs.reserve(semanticObjs.size());
   for (uint32_t i = 0; i < semanticObjs.size(); ++i) {
-    mapColorIntsToSemanticObjIDXs.insert({semanticObjs[i]->getColorAsInt(), i});
+    mapColorIntsToSemanticObjIDXs.emplace(semanticObjs[i]->getColorAsInt(), i);
   }
   // build map with key being semanticObject IDX in semantic Objects array
   std::unordered_map<uint32_t, std::vector<scene::CCSemanticObject::ptr>>