Factorize zoomToLayer,LookAtCoordinates

[gchoqueux]

https://github.com/iTowns/itowns/blob/bbdd27d9eab2c32876162b22e065c666b1674c55/examples/jsm/PointCloudHelper.js#L47C1-L68C1

This feature was already started in CameraUtils.animateCameraToLookAtTarget ,

This feature allows you to position the camera on coordinates or an extend. It works in both planar and globe viewers. It takes into account the loading of the DTM, which can cause the terrain to pass over the camera. There are several parameters: tilt, heading, distance, animated. It is used in GlobeControls and could also be used in PlanarControls. This is a possibility for factorization. For this, the layer must have a footprint property. I had asked @ftoromanoff to keep it in Clouds Layer. Unfortunately, I don't have time to start this factorization at the moment.

[Desplandis]

First thing first, we should document CameraUtils. I would gladly have used this function if I was aware of its existence! The code cited in your message was already a factorisation of duplicated code in all point cloud examples.

Don't have time to do this factorisation too.

[gchoqueux]

Indeed, the documentation is quite sparse for camera utils.
This is just a small note of caution to raise before using these features.
Unfortunately, I have several topics to deal with before I can start working on this refactoring and improving the documentation.