Merge pull request #9683 from sebavan/master

Fix #9682

src/Cameras/followCamera.ts

@@ -3,7 +3,7 @@ import { serialize, serializeAsMeshReference } from "../Misc/decorators";
 import { Tools } from "../Misc/tools";
 import { TargetCamera } from "./targetCamera";
 import { Scene } from "../scene";
-import { Matrix, Vector3 } from "../Maths/math.vector";
+import { TmpVectors, Vector3 } from "../Maths/math.vector";
 import { Node } from "../node";
 import { AbstractMesh } from "../Meshes/abstractMesh";
 import { FollowCameraInputsManager } from './followCameraInputsManager';
@@ -130,14 +130,10 @@ export class FollowCamera extends TargetCamera {
             return;
         }
 
-        var yRotation;
-        if (cameraTarget.rotationQuaternion) {
-            var rotMatrix = new Matrix();
-            cameraTarget.rotationQuaternion.toRotationMatrix(rotMatrix);
-            yRotation = Math.atan2(rotMatrix.m[8], rotMatrix.m[10]);
-        } else {
-            yRotation = cameraTarget.rotation.y;
-        }
+        var rotMatrix = TmpVectors.Matrix[0];
+        cameraTarget.absoluteRotationQuaternion.toRotationMatrix(rotMatrix);
+        var yRotation = Math.atan2(rotMatrix.m[8], rotMatrix.m[10]);
+
         var radians = Tools.ToRadians(this.rotationOffset) + yRotation;
         var targetPosition = cameraTarget.getAbsolutePosition();
         var targetX: number = targetPosition.x + Math.sin(radians) * this.radius;