Re: NOVA programming

From: Jo Even Skarstein <joska_at_nuts.edu>
Date: Thu, 16 Apr 1998 14:14:04 +0200

On Wed, 15 Apr 1998, Petr Stehlik wrote:

> JES>If you need to copy from/to the videoram, then move.l should be
> JES>fastest.
>
> Apparently this is much slower than Doug's c2p routines to super slow
> 256-color mode ST-RAM. I don't get it.

Neither do I :-) If the image you have in ST-RAM already is in the
correct format (e.g. Nova 15bit), then nothing should be faster than a
move.l-routine. Don't use movem on your AB though ;-)

You can also use the blitter, but apparently it's not faster than the
CPU unless you need to transform the image in some way. But you could
perhaps save some time by doing some work in the 040's cache while the
blitter works.

> JES>You can use VDI to change the CLUT if you're working in 256 colour
>
> I was writting a .TTP program, so it was hard to call VDI. However as I
> need to call wind_update I will have to convert it to GEM app :-/

The only "clean" way of changing the Nova CLUT is via VDI, but you
could also write directly to the Nova registers.


/*
** Jo Even Skarstein http://www.stud.ntnu.no/~josk/
**
** beer - maria mckee - atari falcon - babylon 5
*/
Received on to. april 16 1998 - 14:14:04 CEST

This archive was generated by hypermail 2.3.0 : ti. nov. 03 2015 - 20:07:54 CET