CESIUM OriginShiftComponent - Callback needed for Volumetric Clouds

Cesium for Unreal
1

Hi,

we are succesfully using the OriginShiftComponent with “Change Cesium Georeference” for our full-globe flight simulator, it’s a great feature!

But when using origin shift with volumetric clouds (or Ultra Dynamic Sky), with every rebasing the clouds jump.

This can be solved by feeding the changed actor position into the cloud material via MPC. But I still get a one-frame-cloud jitter, because I don’t have a callback from the CESIUM Origin Shift, so my update to the clouds shader is one frame too late.

Solution: It would be awesome to get an Blueprint Callback Event node that activates directly after the origin shift happened.

Thanks & best
Andreas

2

You should be able to subscribe to the change in the CesiumGeoreference origin itself. See the OnGeoreferenceUpdated event on ACesiumGeoreference.

1 Like
3

Thanks @Kevin_Ring ,
will look into this!
Best
Andreas

4

Hi @Kevin_Ring,

works like a charm, just adding the Blueprint implementation for others who might need this, too:

EventOnGeoreferenceUpdated
EventOnGeoreferenceUpdated1273×595 89.4 KB

I placed this in the Level Blueprint, but you can add it wherever you want.

Best
Andreas

5

I guess this is to add the offset afterwards to absolute world position nodes by means of material parameter collections, right? If that is the case, did you find any precision loss problems after some time running? Does the offset grow indefinitely and cause precision loss? Is there a way to avoid this?