Deferral States

GKS allows the programmer to defer sending output to a workstation by calling the function Set Deferral State. For example, it might be more efficient to send primitives in batches, rather than one at a time. Thus, 'As Soon As Possible' often may not be as fast as possible! For most users of GKS the default values should be acceptable (but note that these are device-dependent). The call is:

CALL GSDS(WKID, DEFMOD, REGMOD)

The second argument, DEFMOD, controls when output should be sent to the workstation specified by WKID, and can take the following values:

'GASAP'

send output As Soon As Possible

'GBNIG'

send output Before Next Interaction Globally. This makes sure that the workstation is up-to-date before the next input action on any open workstation

'GBNIL'

send output Before Next Interaction Locally. This makes sure that the workstation is up-to-date before the next input action on the workstation specified in the call

'GASTI'

At Some TIme allows GKS to choose some opportune moment to bring the workstation up-to-date

The third argument, REGMOD, controls what should happen on those workstations which require the image on the display to be regenerated in some circumstances. For example, to delete a segment on a direct view storage tube display, such as a TEKTRONIX 4014, would require the screen to be cleared and then the remaining contents re-drawn.

This is called implicit regeneration. REGMOD can take the following values:

'GSUPPD'

Re-drawing is suppressed until an update is forced by calling the Update Workstation function, GUWK, or by re-drawing all the segments with GRSGWK.

'GALLOW'

Immediate re-drawing is allowed.