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Using the Cursors

  Each image display has two independent cursors available. The first cursor (cursor 0) is moved via the mouse, the second cursor (cursor 1) is moved via the Arrow keys on the keyboard.

Using both cursors a region of interest ( ROI) is supported. The ROI can have rectangular or circular shape and is moved via the mouse, its size is adjusted via the Arrow keys. The resizing of the ROI may be done in small or large increments. This is controlled via the number keys 0, 1, 2, ..., 9 on the keyboard. Pressing the 0--key corresponds to an increment of a single screen pixel, whereas 1, 2, ..., 9 lead to larger increments.

The cursor position can be read by pressing the ENTER button which is the leftmost button on the mouse. To exit from a command which uses interactive cursor input, press the EXIT button which is the rightmost button on the mouse. The middle button is currently not used in MIDAS (it behaves like the EXIT button), but may be employed in the future. The RETURN key on the keyboard serves as an EXECUTE button. The EXECUTE button works usually like the ENTER button, only in some very special cases its functionality is different from the ENTER button. If so, it is explained in the relevant help info, an example are the MAGNITUDE/... commands.

Pressing the ENTER button on the mouse requires a stable hand. If you press the ENTER button and only slightly move the mouse by doing so, this will be interpreted by the display server as a Cursor Move instead. Therefore, it may be safer to move the cursor via the mouse but get the cursor input with the EXECUTE button.
The commands associated with cursor control operations are:

GET/CURSOR - read cursor positions
SET/CURSOR - define specific cursor shape



next up previous contents index
Next: Look--Up Tables Up: XWindow display Previous: Using Image Memories



Rein Warmels
Mon Jan 22 12:06:29 MET 1996