Introduction to a user co-ordinate system

The definition of points may be facilitated by the application of a user co-ordinate system. This system can be so defined (i.e. positioned and oriented) that it reflects the geometry of the model (or its part) that is being defined.

The user can define as many user co-ordinate systems as necessary. However, only one of them can be active in one graphical window at a time. Nevertheless, the user may swap between individual user co-ordinate systems at any time. What’s more, even a new user co-ordinate system may be defined any time it is necessary or efficient to do so.

The active user co-ordinate system is indicated on the program status bar.