Robert Purves wrote:

> Rick Brown said:-
> >Sending the same drawing commands to an offscreen GWorld would not speed
> >things up, I think.
>
> Reluctant as I am to disagree with Rick, a direct comparison shows the
> answer to be "yes, and by a substantial factor"  ---   4-5 times faster (on
> an iMac). See the comparison program below.

This is interesting.  I too found the GWorld draw to be faster (by a factor of
almost 3 on my G3).  Here's a speculation:  When drawing to screen, QD surely
has to check the current status of the clip region and vis region before
_each_ drawing command.  But since those regions never change in a GWorld, QD
shouldn't have to perform that check.  Maybe that's enough to accont for the
speed difference.

Thanks to Robert for providing actual experimental results!

- Rick