[comp.sys.amiga] Oneplane scroll speed

davea@vlsi.ll.mit.edu (Dave Allen) (01/06/89)

Not too long ago, Ethan Dicks (erd@saqqara.cis.ohio-state.edu) posted
a program called oneplane.c which reduces your workbench screen to one
bitplane, speeding up text scrolling.  I did some timing experiments to
see how much speedup you get.

I used a 720-line, 31-K text file on RAM: under WB 1.2 on my A1000.  My
text window was morerow'd to 25x80 characters.  I used c:type to test 
the scrolling speed, and used DME 1.21 to page-down through the file
to test full-screen rendering time.  This second test involved hitting
the page-down key 25 times; it took me four seconds to hit the key that
many times, so 4 sec is the minimum possible time.  I also did the
scroll test using the built-in "cat" command of the Drew/Dillon shell 2.07.

                   Scroll time  Page time
Vanilla system:      52 sec       10 sec (page redraw visible)
With oneplane:       42 sec        8 sec (flicker on page redraw)
With BlitzFonts:     42 sec       4? sec (almost no flicker on redraw)
With both:           34 sec       4? sec
Using cat with both: 22 sec        -

Dave Allen: internet davea@ll-vlsi.arpa or @vlsi.ll.mit.edu