==== Grouping ====
To make a grouping in a Surface file:
  - Set up a groupings panel by creating a SurfaceView and then selecting Groupings from the top left (or right clicking on the surface view object)
  - Manipulate your materials such that the precise set of features that you want the group to recall is displayed - this **includes** holes left by removing materials.
  - On the Groupings panel select New Group and give it a name.

Groupings can be manipulated by either the (very slow) **Show** command which removes all other elements and displays only the Group, the **Add/Remove** commands which do what you might expect, and the **Nop** option which does no operation. Groups are easily renamed just be altering the name in the text field. The order is harder to change - one must redefine the groups from start to finish by selecting the group, creating a new group from it and then deleting the old one. There may be a more elegant solution.

Groupings are saved as part of the .surf file