SR mode zooming is very hard

[JustinPrivitera]

In SR mode, rotating a dataset is easy because a bounding box is rendered while you are rotating, and then once you let go of the mouse the full image renders. But zooming in and out with the mouse is very difficult because VisIt wants to render many intermediate stages of the zoom. It would be nice if SR mode gave you a bounding box when zooming much like when rotating.

VisIt 3.4.2 beta.