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Graphical Input

Graphical coordinate input activates a ``cross-hair'' cursor, so that horizontal and vertical alignment is easier. During input of a series of connected coordinates a ``rubber-band'' may be drawn from a previous coordinate, and a line may be used to join the input coordinates. Similarly, if a rectangular region is to be defined by two coordinates a ``rubber-band'' box will be drawn from the first input coordinate whilst inputing the second. Certain coordinate inputs, e.g. the ``ZOOM IN'' button command, produce a special ``spy-glass'' or ``looking glass'' window showing in greater detail the region around the graphics cursor (V7.32). As the cursor moves, so this display region will change.

Text input is now available within the graphics system (V7.22). This supports ``command recall'' and command editing, using the arrow keys. Text may edited, by using the left and right arrow key to move to the required character. Newly typed text is automatically inserted at the cursor position, and the <DELETE> key (or the <BACKSPACE>) may be used to delete characters before the cursor. Often a default value will be presented. This may be edited, or the down arrow key may be used to remove it.

At present all graphical input and menus appear within the same window as the image display. Eventually a separate graphical menu window is desirable.


next up previous contents index
Next: X-11 Restrictions Up: The Graphics System Previous: Colour Map Usage
Andrew Hammersley
2004-01-09