(v13) AbortHalftone

This page applies to Harlequin v13.1r0 and later; both Harlequin Core and Harlequin MultiRIP

There are times when the renderer needs to abort rendering, such as when a failure occurs, or a job is interrupted.

If requests have been passed to a Screening module via DoHalftone, and any such request has not been notified as having been completed when the renderer needs to abort, the screening module will be informed using an AbortHalftone call for each such request.

The screening module must take any action necessary and confirm the abort as quickly as possible. The outstanding request should also be marked as complete, by invoking DoneHalftone , albeit possibly with a failure indication.

Only if a serious impediment exists, such as an outstanding DMA transfer, may the screening module refuse the abort. In such a case the RIP will repeat the AbortHalftone attempt periodically.

The screening module will also subsequently receive a render completion, with a Boolean indicating that rendering was aborted, so as to allow further tidying up as necessary.

The subsequent render completion will not take place until the render abort has succeeded.

Note that the screening module must be prepared to receive an AbortHalftone even when it is in the process of notifying the RIP that it has completed all its DoHalftones (because they cannot be synchronized). The screening module should deny the abort in such a case; otherwise, the RIP could try to do render completion before the DoneHalftone calls have finished.