I added a 2d multi-resolution rendering capability for 2d AMR data. It
only reads in the blocks with cells that are larger than the user
specified smallest cell size and are within the current view. The multi-
resolution controls are located in the rendering options window, which
can be brought up by selecting "Options->Rendering..." from the main
menu bar. The blocks read in will change as the user pans and zooms the
image.

The 2d multi-resolution capability is extensible into 3d in straight
forward manner, I just haven't had time to do it.



git-svn-id: http://visit.ilight.com/svn/visit/trunk/src@16576 18c085ea-50e0-402c-830e-de6fd14e8384