[REBOL] Re: Amiga View text rendering (was rebol/view on a 486?)
From: chris:starforge:demon at: 21-Jun-2001 11:00
Carl Read wrote:
> Oh well...
>
> Other 060 users? Is it just his lack of a gfx-card that's slowing his
> text-entry down so much, or is it still sluggish with a decent card?
Without knowing how /View works (in other words - this could be utter
tripe, so don't read too much into it), I'd guess that /view does all
its work in a chunky buffer which is then shown on screen. With a
graphics card you're the limited by the size of your app and the fill
rate of your graphics chipset, usually many times faster than AGA. If
you aren't working in graphics memory then you're also limited by the
transfer rate to the graphics memory, but compared to the core bus on
the Amiga, this is trivial.
But with AGA you need to do a c2p conversion. This is Not Fast at the
best of times and even areas as small as 320x256 can bog an Amiga down
regardless of processor: the bottleneck is the chipram bus, not the
processor, as the planar information has to be written into a chipram
buffer for the blitter to get at it. Go up to normal application sizes
like 640x480/800x600 and you're looking at a LOT of work per frame and
the bus bottleneck has a serious impact on performance.
Getting a graphics card will increase the speed of all graphical
operations - the amount /view will benefit depends largely on how wide
of the mark I am with these guesses.
Chris
