Merge pull request #5682 from nathankmiller/master

Updated comment to reflect that property can return null as well as undefined

dist/preview release/what's new.md

@@ -131,6 +131,7 @@
 - Update physics position using absolutePosition instead of pivotPosition ([TrevorDev](https://github.com/TrevorDev))
 - Disable camera arrow key controls when the Command key is selected on Mac OS ([kcoley](https://github.com/kcoley))
 - Viewer should not set receiveShadows on an instanced mesh ([TrevorDev](https://github.com/TrevorDev))
+- Updated comment in TransformNode.rotationQuaternion to include undefined as one of the potential return values ([nathankmiller](https://github.com/nathankmiller))
 
 ### Core Engine
 - Fixed a bug with `mesh.alwaysSelectAsActiveMesh` preventing layerMask to be taken in account ([Deltakosh](https://github.com/deltakosh))

src/Mesh/babylon.transformNode.ts

@@ -156,7 +156,7 @@ module BABYLON {
         }
 
         /**
-         * Gets or sets the rotation Quaternion property : this a Quaternion object defining the node rotation by using a unit quaternion (null by default).
+         * Gets or sets the rotation Quaternion property : this a Quaternion object defining the node rotation by using a unit quaternion (undefined by default, but can be null).
          * If set, only the rotationQuaternion is then used to compute the node rotation (ie. node.rotation will be ignored)
          */
         public get rotationQuaternion(): Nullable<Quaternion> {