Merge pull request #6120 from bghgary/loader-perf-fix

Block material dirtying during load in glTF loader

dist/preview release/what's new.md

@@ -135,6 +135,8 @@
 - Added customShaderNameResolve to PBRMaterialBase to allow subclasses to specify custom shader information [MackeyK24](https://github.com/mackeyk24))
 - Added PBRCustomMaterial to material library to allow easy subclassing of PBR materials [MackeyK24](https://github.com/mackeyk24))
 - Added `auto-exposure` support in `StandardRenderingPipeline` when `HDR` is enabled ([julien-moreau](https://github.com/julien-moreau))
+- Add `EquiRectangularCubeTexture` class to enable the usage of browser-canvas supported images as `CubeTexture`'s ([Dennis Dervisis](https://github.com/ddervisis))
+- Add `EquiRectangularCubeTextureAssetTask` to be able to load `EquiRectangularCubeTextures`s via Asset Manager ([Dennis Dervisis](https://github.com/ddervisis))
 - Added `Matrix.RotationAlignToRef` method to obtain rotation matrix from one vector to another ([sable](https://github.com/thscott))
 - ArcRotateCamera will now cache the necessary matrices when modifying its upVector, instead of calculating them each time they're needed ([sable](https://github.com/thscott))
 
@@ -152,8 +154,7 @@
 - Skinned meshes now behave as intended by glTF ([bghgary](https://github.com/bghgary))
   - Skinned meshes now set an override mesh instead of reparenting to the `__root__` transform node
   - Loaded bones are linked with the transform node created for the corresponding glTF node
-- Add `EquiRectangularCubeTexture` class to enable the usage of browser-canvas supported images as `CubeTexture`'s ([Dennis Dervisis](https://github.com/ddervisis))
-- Add `EquiRectangularCubeTextureAssetTask` to be able to load `EquiRectangularCubeTextures`s via Asset Manager ([Dennis Dervisis](https://github.com/ddervisis))
+- Improve load performance by blocking material dirtying during load ([bghgary](https://github.com/bghgary))
 
 ### glTF Serializer
 

loaders/src/glTF/2.0/glTFLoader.ts

@@ -273,6 +273,10 @@ export class GLTFLoader implements IGLTFLoader {
 
             const promises = new Array<Promise<any>>();
 
+            // Block the marking of materials dirty until the scene is loaded.
+            const oldBlockMaterialDirtyMechanism = this._babylonScene.blockMaterialDirtyMechanism;
+            this._babylonScene.blockMaterialDirtyMechanism = true;
+
             if (nodes) {
                 promises.push(this.loadSceneAsync("/nodes", { nodes: nodes, index: -1 }));
             }
@@ -281,6 +285,9 @@ export class GLTFLoader implements IGLTFLoader {
                 promises.push(this.loadSceneAsync(`/scenes/${scene.index}`, scene));
             }
 
+            // Restore the blocking of material dirty.
+            this._babylonScene.blockMaterialDirtyMechanism = oldBlockMaterialDirtyMechanism;
+
             if (this._parent.compileMaterials) {
                 promises.push(this._compileMaterialsAsync());
             }