Error trying to apply motion blur

Questions
1

I’m trying to use motion blur in my project, and am just initializing it like so:

const motionBlur = new MotionBlurPostProcess('mb', window.scene, 1.0, this.camera);
motionBlur.isObjectBased = false;

However, I get the following error:

ocess.ts:308  Uncaught TypeError: Cannot read properties of undefined (reading '-1')
    at MotionBlurPostProcess._onApplyScreenBased (motionBlurPostProcess.ts:308:87)
    at Observer.onApply [as callback] (motionBlurPostProcess.ts:259:53)
    at Observable.notifyObservers (observable.ts:332:49)
    at MotionBlurPostProcess.apply (postProcess.ts:854:32)
    at PostProcessManager._finalizeFrame (postProcessManager.ts:203:31)
    at Scene._renderForCamera (scene.ts:3634:37)
    at Scene._processSubCameras (scene.ts:3649:18)
    at Scene.render (scene.ts:3911:18)
    at renderLoop (appStart.ts:105:13)
    at Engine._renderFrame (engine.ts:1279:13)
_onApplyScreenBased @ motionBlu

Any ideas how to resolve this?

2

I believe you are using tree shaking. How do you import MotionBlurPostProcess?

3

It’s part of a lot of imports here:

import {
  Nullable,
  Scene,
  Vector3,
  MeshBuilder,
  ArcRotateCamera,
  UniversalCamera,
  InstancedMesh,
  Mesh,
  AbstractMesh,
  Camera,
  Matrix,
  Frustum,
  Plane,
  TransformNode,
  Animation,
  Animatable,
  Observer,
  BezierCurveEase,
  ArcRotateCameraPointersInput,
  DeepImmutable,
  Quaternion,
  MotionBlurPostProcess,
} from '@babylonjs/core';
4

This configuration works fine for me.
Could you also check if the variable window.scene is valid? Probably it should be this.scene?

5

Motion blur is using the prepass renderer by default, try adding import "@babylonjs/core/Rendering/prePassRendererSceneComponent" to your imports.

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