You can also position the slice sphere using VisIt's interactive sphere tool. The sphere tool, available in the visualization window's popup menu, allows you to position and resize a slice sphere interactively using the mouse. The sphere tool is an object in the visualization window that can be moved and resized. When the sphere tool is changed, it gives its new slice sphere to the SphereSlice operator. For more information about the sphere tool, read the Interactive Tools chapter.