rename numInstances to initialInstances in loadGltf methods.

when initialInstances > 0, don't wait for createInstance to be called to create corresponding GltfSceneAsset

thermion_dart/native/include/scene/GltfSceneAsset.hpp

@@ -33,8 +33,7 @@ namespace thermion
             Engine *engine,
             utils::NameComponentManager* ncm,
             MaterialInstance **materialInstances = nullptr,
-            size_t materialInstanceCount = 0,
-            int instanceIndex = 0);
+            size_t materialInstanceCount = 0);
 
         ~GltfSceneAsset();
 

thermion_dart/native/src/scene/GltfSceneAsset.cpp

@@ -33,15 +33,16 @@ namespace thermion
         Engine *engine,
         utils::NameComponentManager* ncm,
         MaterialInstance **materialInstances,
-        size_t materialInstanceCount,
-        int instanceIndex) : _asset(asset),
+        size_t materialInstanceCount) : _asset(asset),
                                   _assetLoader(assetLoader),
                                   _engine(engine),
                                   _ncm(ncm),
                                   _materialInstances(materialInstances),
                                   _materialInstanceCount(materialInstanceCount)
     {
-        createInstance();
+        for(int i = 0; i < asset->getAssetInstanceCount(); i++) {
+            createInstance();
+        }
         TRACE("Created GltfSceneAsset from FilamentAsset %d with %d reserved instances", asset, asset->getAssetInstanceCount());
     }