next up previous 530
Next: PICXY - Creates a new FRAME picture defined by co-ordinate bounds
Up: Specifications of KAPPA applications
Previous: PICTRANS - Transforms a graphics position from one picture co-ordinate Frame to another


PICVIS - Finds the first unobscured FRAME picture in the graphics database

Description:
This application selects the first, i.e. oldest, unobstructed FRAME picture in the graphics database  for a graphics device. Unobstructed means that there is no younger picture overlying it either wholly or in part.

Usage:
picvis [device]

Parameters:
DEVICE = DEVICE (Read)
The graphics workstation. [The current graphics device]

Examples:
picvis
This selects the first unobscured FRAME picture for the current graphics device.
picvis xwindows
This selects the first unobscured FRAME picture for the xwindows graphics device.

Notes:
  • An error is returned if there is no unobscured FRAME picture, and the current picture remains unchanged.

  • This routine cannot know whether or a picture has been cleared, and hence is safe to reuse, as such information is not stored in the graphics database.


Related Applications :
KAPPA: PICEMPTY, PICENTIRE, PICGRID, PICLAST, PICLIST, PICSEL.

Timing :
The execution time is approximately proportional to a linear combination of the number of pictures in the database before the unobstructed FRAME picture is found, and the square of the number of pictures in the database.



next up previous 530
Next: PICXY - Creates a new FRAME picture defined by co-ordinate bounds
Up: Specifications of KAPPA applications
Previous: PICTRANS - Transforms a graphics position from one picture co-ordinate Frame to another

KAPPA --- Kernel Application Package
Starlink User Note 95
Malcolm J. Currie & David S. Berry
2014 May 5
E-mail:starlink@jiscmail.ac.uk

Copyright © 2014 Science and Technology Facilities Council