[comp.sys.mac] QuickDraw performance boosting

pjw@usna.MIL (Prof. Peter Welcher) (02/18/90)

I've got a program where my chief performance problem is writing to the
screen. (Any others are pure coding problems.)  It seems like QuickDraw
bottleneck procedures are aptly named.

Various people have suggested using off-screen bitmaps.  Benchmarking seems
to refute the theory that this produces faster results: you have the drawing
cost *plus* the CopyBits cost. Am I missing something ?

I'd appreciate it if anyone could share folk-wisdom on fast screen drawing
(lines & text). I don't need gory details, just a sketch or a fresh idea.

The program involves a spreadsheet-like display. I've found that drawing
lines around cells is much worse than drawing a grid, presumably because
many more lines are being clipped. There are other, fairly obvvious,
improvements I've been able to make. What I'm looking for is things like
off-screen bitmaps: whole approaches to fast drawing that I might not have
thought of. Tricks of the trade, etc.

Since I read the news groups irregularly, and mayy lose a reply
in the clutter, I'd appreciate email responses:

	pjw@sma.usna.navy.mil

Thanks !