Issue with newer Cesium releases

Recently, I updated to the latest Cesium build and am having issues. What I’m seeing is my custom C++ actors with anchor components no longer move to the correct location when calling MoveToLongitudeLatitudeHeight(). Now, more data points: using the same entity code but on a different level works fine. I’ve recreated the georeference in the non-working level (so make sure it wasn’t something messed up in there) but it didn’t affect the behavior. To try to debug this, at the point where I call MoveToLongitudeLatitudeHeight(), I also added debug code to manually calculate the unreal coordinates that correspond to the desired Long/Lat/Height and compare against the actor’s position after the call to MoveToLongitudeLatitudeHeight() - in the broken case, the two values are different - in the working case, they’re the same. Also, if I create an entity manually (say, a simple cube) and attach a globe anchor to it, it goes to the correct location. This points me to something wrong in my C++ code for the entity but I can’t find anything obvious (that would have broken with recent Cesium releases). Any ideas where to look?

Thanks.

-John

A small bit more to add:

  • the entities are created programatically after the level’s BeginPlay().
  • the manually created entity I talk about above was created in the outliner, not programatically - so that is a difference.
  • The georeference scales are different in my two levels (one is 100 and the other is 0.001).

Well, I don’t know, without seeing your project. But since you said it used to work in a previous version of Cesium for Unreal, the first step is to confirm that and then determine in which version it broke. That will help narrow down what’s going wrong. You can find old versions of Cesium for Unreal here:

Instructions for installing these versions can be found here:

I’m looking at this again today. The issue came with the move to V2.0 of Cesium which had a bunch of breaking changes to the Georeference API (renamed transformation methods, etc). Let me know if that version has anything I can go check and I’ll keep digging on my end.

Thanks.

Further debugging. I’ve verified in UE’s editor that the LLA and ECEF values for the globe anchor (on one of the entities) are correct.