Difficulties Controlling Camera

I often experience problems manipulating the camera with 1) the mousewheel and 2) the ctrl key.

I’ve attached sandcastle code at the bottom of this post. If I notch the mousewheel forward twice, which should make it zoom in, it actually zooms out so far that I can’t see the polyline and wall anymore. Zooming out seems to work ok. If you don’t get these results at first, try moving the camera around a bit, then zooming in. I often get a severe jump in position when using the mousewheel in Cesium.

In the sandcastle, I’d like to be able to hold down the ctrl key, then click and drag the mouse up until the camera is very close to the ground, then, without letting go of the ctrl key, get back to where I was by dragging the mouse back down. In the sandcastle example below, I use the red object as the anchor point. Often I’m not able to rotate the camera back up to where it was. After I’ve manipulated the camera a bit, the rotation becomes even more unpredictable, especially as the camera gets close to the ground.

Are there any solutions to these problems? Is this something that has been seen before? We don’t want users to be come frusterated because the camera is difficult to control.

Here’s a video that might help illustrate the problems as well: https://www.youtube.com/watch?v=M6AZ8PyM49M

Sandcastle Code:


I believe the sky disappearing error was recently fixed with this pull request: https://github.com/AnalyticalGraphicsInc/cesium/pull/3032. The fix will be included in the next release.

I created a new issue for the scroll wheel problem: https://github.com/AnalyticalGraphicsInc/cesium/issues/3037

In the mean time, we recommend using right click + drag to zoom in and out. The behavior is a lot more predictable.