🚀 go-pugleaf

In article <BzDsD6.C2D@cantua.canterbury.ac.nz>, cree@elec.canterbury.ac.nz (Michael Cree) writes:
> Lawrence D'Oliveiro, Waikato University (ldo@waikato.ac.nz) wrote:
>> That 2000 frame-per-second rate would apply if you were just changing a
>> copper-list register to point to a different image which is already in chip
>> RAM (and as someone else has pointed out, 500 microseconds is really pretty
>> slow for such a simple operation). Thus any claim that an Amiga can animate at
>> this speed for any length of time (even with unlimited fast RAM) can't be the
>> whole truth, and I claimed no more than this.
>
> As I understand it that figure is for copying from a memory buffer
> into the display buffer as I explained in a previous reply to your
> posting. If it was just changing the copper list it could be done
> probably close to a million times per second (since that is how long
> the operation takes) ...

Is that from a buffer in fast RAM to one in chip RAM? If so, it's pretty
impressive, since I gather you can't use the blitter for an operation like that.

How many bytes are you talking about, though? At 320*200 resolution, a
single bitplane takes up 8000 bytes (or so my calculator tells me). Is that
the time to move 5 bitplanes, or are you talking about some other screen mode?

Lawrence D'Oliveiro                       fone: +64-7-856-2889
Computer Services Dept                     fax: +64-7-838-4066
University of Waikato            electric mail: ldo@waikato.ac.nz
Hamilton, New Zealand    37^ 47' 26" S, 175^ 19' 7" E, GMT+13:00