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Using the Cursors

Each display window 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, its center is moved via the mouse and 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.
You can also create a special cursor window for each display. Then, the area in the display window in cursor focus is also shown in that cursor window with a fixed magnification. Commands associated with cursors are:
GET/CURSOR - read cursor positions
SET/CURSOR - define a specific cursor shape
CREATE/CURSOR_WINDOW - create cursor w. for existing display
DELETE/CURSOR_WINDOW - delete a cursor w.

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