🚀 go-pugleaf

>> I just recently got "popi", the image processing program described in 
>> Gerald Holzmann's book "The Digital Darkroom"; this program runs on a variety
>> of systems, but the conditionally-compiled Amiga code is really really slow,
>> and I'd like to fix this.  So.

The problem isn't really the Amiga specific code; the problem is that
the thing is just plain slow (it's barely useable on a DECStation
3100, at 14 MIPS). The heart of the code is a loop that interprets the
stack-machine code for the transformation expression once for every
pixel on the screen.

The easy solution is to use fewer pixels - say 128x128 instead of
512x512; giving you a factor of 16 increase in speed with no work. The
hard solution is to rewrite the "compiler" to generate a loop that
runs in 68K machine language & run that, instead of generating
stack-machine code and interpreting that (this is what pico, mentioned
in the book, did). An intermediate solution is to write something that
translates the stack-machine code into 68K ML, and run that instead of
the stack-machine code.

Of course, speeding up the display code wouldn't hurt. But I don't see
much point until the transformation code is fixed. In any case, the
best way I can see to do the drawing code is to have the blitter move
one (two?) bit-plane at a time from the image array into the drawing
area. You could also do this for each scan line, but that will be
slower.

Whatever you do, let us know!

	<mike

--
He was your reason for living				Mike Meyer
So you once said					mwm@berkeley.edu
Now your reason for living				ucbvax!mwm
Has left you half dead					mwm@ucbjade.BITNET