Use operator[] instead of at() when the idx is checked

apps/openmw/mwrender/groundcover.cpp

@@ -220,7 +220,7 @@ namespace MWRender
                 calculator.reset();
                 for (size_t i=0; i<cell->mContextList.size(); ++i)
                 {
-                    unsigned int index = cell->mContextList.at(i).index;
+                    unsigned int index = cell->mContextList[i].index;
                     if (esm.size() <= index)
                         esm.resize(index+1);
                     cell->restore(esm[index], i);

apps/openmw/mwworld/projectilemanager.cpp

@@ -319,7 +319,7 @@ namespace MWWorld
 
         // in case there are multiple effects, the model is a dummy without geometry. Use the second effect for physics shape
         if (state.mIdMagic.size() > 1)
-            model = "meshes\\" + MWBase::Environment::get().getWorld()->getStore().get<ESM::Weapon>().find(state.mIdMagic.at(1))->mModel;
+            model = "meshes\\" + MWBase::Environment::get().getWorld()->getStore().get<ESM::Weapon>().find(state.mIdMagic[1])->mModel;
         state.mProjectileId = mPhysics->addProjectile(caster, pos, model, true, false);
         state.mToDelete = false;
         mMagicBolts.push_back(state);