1. A concise explanation of the problem you're experiencing.
I would like to enable the ability to click and drag to move the camera while maintaining a constant height above the ellipsoid as in the demo on the Cesium homepage. I would also like to initialize the camera to be looking at a particular point from a particular distance away with a particular orientation.
If I do not make a call to camera#lookAt this click and drag to move the camera behavior works as I would like it to. After I make a call to camera#lookAt, the click and drag behavior is to pivot around the target specified.
2. A minimal code example. If you've found a bug, this helps us reproduce and repair it.
const cartoTarget = Cesium.Cartographic.fromDegrees({{location.latLng.longitude}}, {{location.latLng.latitude}}, heightAboveEllipsoidM);
const target = Cesium.Cartographic.toCartesian(cartoTarget);
viewer.camera.lookAt(target, new Cesium.HeadingPitchRange(heading, pitch, range));
3. Context. Why do you need to do this? We might know a better way to accomplish your goal.
Just seeking the desired behavior. Open to suggestions.
4. The Cesium version you're using, your operating system and browser.
I am using Cesium 1.43, macOS 10.13.3, Chrome 65.0.3325.162