NAME

track − asynchronously echo an input device’s locator position on an output device. 

SYNOPSIS

C SYNTAX

void track(indev,outdev,locator_num);
int indev,outdev,locator_num;

FORTRAN77 SYNTAX

        subroutine track(indev,outdev,locator_num)
        integer*4 indev,outdev,locator_num

PASCAL SYNTAX

procedure track(indev,outdev,locator_num:integer);

HP-UX COMPATIBILITY

Level: HP-UX/STANDARD

Origin: ANSI Computer Graphics Interface

DESCRIPTION

INPUT PARAMETERS

indev
the file descriptor for the input device whose locator subdevice is to be tracked.
outdev
the file descriptor for the output device whose echo is to be used to track the input device.
locator_num
the number of the locator subdevice on the specified input device whose position is to be tracked.  (The number of locators on a device may be obtained using the inquire_sizes procedure.) 
 

DISCUSSION

Track sets up asynchronous tracking of an input device’s locator position onto an output device’s view surface.  The locator position in Virtual Device Coordinates is mapped onto the Virtual Device Coordinates of the output device.  If the vdc extents of the two devices are not similar, then the tracking movement will be either exagerated or reduced. 

SEE ALSO

track_off(3g). 

Hewlett-Packard Company  —  May 11, 2021