#### Cube Navigation

Navigation in three dimensions with a two-dimensional screen and mouse is a bit of a challenge. However, the actions listed below should make it fairly straightforward to navigate around points in 3d space to zoom in on the regions that you are interested in.

Left drag
  Rotate. Rotates the view cube about its center.
Wheel
  Isotropic zoom. Spinning the mouse wheel forwards/backwards zooms the space in the view cube in/out around the cube center. The mouse position does not affect it.
Right drag (CTRL-drag)
  2d stretch zoom. Dragging with the right button does a stretch zoom in the two dimensions best aligned with the plane of the screen. There is no movement in the third (mostly perpendicular to the screen) direction. The zoom is around a line defined by the position of the mouse at the start of the zoom, pointing along the third dimension. You can stretch/squash in both directions by dragging the mouse up/down/left/right - it's easier to try it than to explain it.
Center drag (SHIFT-drag)
  2d pan. Dragging with the center button pans the 3d space in the two dimensions best alighned with the plane of the screen. There is no movement in the third (mostly perpendicular to the screen) direction.
Right click (CTRL-click)
  Re-center. Right-clicking identifies a position in a similar way to the left-click Select action, and then translates the plot so that point is at the center of the view cube. This means that clicking on a cluster will put that cluster in the center of the cube. If you click on an empty region, a position half way between front and back of the cube at that X/Y position will be used.