Bug: bad precision on 0.01 meter sphere

Sandcastle to reproduce:


Generally Cesium seems to fail with sub 1 centimeter primitives and this is a showstopper for our application.

This is even more evident on iOS mobile: it occurs badly already with 1 meter radius:

I would really appreciate some advice on this from Cesium team. I think it is could be related to highp or lowp settings in glsl shaders but could not really find a fix after some searching…

This is significantly worse on iOS, so somehow the GPU precision plays a role here I think?

Here you see the same 1m sphere on PC:


Thank you for bringing this to my attention. I just submitted an issue on GitHub.

The rest of the CesiumJS development team should take a look at it shortly. In the meantime, please update the GitHub issue with additional information as you see fit.


1 Like

Thanks! Thats a very good issue report, great that you were able to reproduce it to a video.

By the way, once piece of extra info:

If we create this kind of sphere as a GLTF model and add it to scene => it works flawlessly and there is no jitter in geometry or positioning.


Thank you for the update - just added it to the GitHub issue.