Before opening an issue on Github, I was wondering if I could have some feedback about an issue we encountered at my workplace.
We have a specific 3D Tileset for which the tiles representing the ‘higher’ level of details, those containing smaller bounding volumes, do not trigger when the camera gets close to them.
This issue only appears when using Cesium js version 1.115.0 and above. The level of details trigger properly when using Cesium js v1.114.0 and lower. See pictures below:
I had a quick look at the root json file and noticed that there are quite a number of tiles which have a boundingVolume with a radius of 0 (BoundingSphere). These tiles have a content field pointing to other subtrees. Could this, in some way, explain the lods not properly triggering?
(I only moved this to the CesiumJS section for now).
When the change of behavior can be pinpointed to versions 1.114 and 1.115, then it might be a form of regression. Quickly skimming over the change log for 1.115, it does mention one point that is related to refinement:
Fixed a bug with where a mix of empty and non-empty tiles were not refining. #9356
that sound that it might be related, but I have not yet investigated thist further.
Thanks for the feedback.
In the meantime I found the exact commit that introduces the issue. It is the following: b4615ec5fff1d2348b8d0e282d2ba3cd42e15105 (Removed the checks for empty leaves )
Thanks for investigating. Maybe @adam_morris has an idea of why this might be happening just by looking at the effect and the commit (in context). Otherwise, we should consider tracking this as an issue, with a link to this thread.
Thanks for pointing out this case. We’ve discussed within the team and we believe a potential workaround is to edit the tileset.json and set the geometric error for the empty tiles to a high value. We have fairly good confidence that this will resolve your issue. If the issue persists let us know and we can look further.
