Two models animate in ION preview but not in Cesium 1.98.1

(Update: 2022-10-19: Unable to determine why Cesium v1.98.1 is unhappy with these 2 animations. Recreating animations in Blender from a fresh source model rather than try to debug. Moving on…)

We have several models with animations created in Blender.
However, two of the models will not animate in 1.98.1 but they do animate fine in the ION preview window. Both have been validated.

Screencast: Two models in ION with tracks/wheels moving (note the asset IDs)

Same two models in Sandcastle 1.98.1 stutter a little and make app somewhat locked up for seconds (though CPU remains normal).
The animation that moves wheels or tracks is “MoveBase”.
Here is a sandcastle with several examples working and the two that do not animate MoveBase are Bulldozer and Backhoe.
(Sandcastle assets will be removed after this issue is closed)

If needed, I can send you the Blender source files.

Hi @bquintrell , I’ve noticed that you’re setting LOOP value but not setting multiplier value after loading the model.

Basically, default animation values are getting reset by applying:

You need to re-assign all these values specially, duration, loop and multiplier

Change this line:

const animation = model.activeAnimations.add({name: anim, loop: Cesium.ModelAnimationLoop.REPEAT});


const animation = model.activeAnimations.add({name: anim, loop: Cesium.ModelAnimationLoop.REPEAT, multiplier: 1.0 });

I have not tested but It should work. Please let us know if it worked or not.

  • Regards

Here is the updated sandcastle changing that one line.
It had no impact - same two fail while the others properly animate.

All models are animating properly at my end in your sandcastle example. Check this sandcastle link. I’ve removed silhouette and increased multiplier value. Starting 3 models are not animating properly seems like issue is inside the model itself.

The Bulldozer and backhoe models do not animate in the link you sent. I have tested and my developers have tested - same results.
Here is what we see with your link.

Also, you cannot increase the multiplier. All animations are calibrated to run at 2.57 miles/hour. We adjust the multiplier based on the current speed of the equipment.

The key point here is that as you can see in the original post, the animations work properly in the ION preview which is NOT running v1.98.1. They fail in 1.98.1. (And they pass the Kronos gltf validator)

I believe the problem is v1.98.1.

(I am running Nvidia driver 522.25 dated 2022-10-12 which is 6 days old. It also fails with last month’s driver.)

It’s running same as you have shown in your screencast link. Bulldozer and backhoe models are animating but not smoothly (in screencast link also). Can you share the blender file or your model here?