> >Look at the Atari 8-bits as a 2600 with more sprites, better resolution,
> >some better color (GTIA mode, 16 shades) and a chip that handles the
kernel
>
> >with its display list rather than a software kernel.
>
> Does anyone know more about that display list? Which things can the ANTIC
> change in each scanline without CPU interaction? Does anyone know
recourses
> on the Internet about that? I'd like to learn more about it...
I just read De Re Atari, so the display list stuff is fresh in my mind.
Display lists on the Atari 8-bit controlled the memory-to-screen mapping
mode and the memory location from which the display was fetched. So, just
using a DL, you could draw the screen from several areas of memory, go
between character and bitmapped modes, and insert blank lines.
To alter anything else, you had to set the display list interrupt on that
line, at which point the 6502 got called to change around hardware
registers. One thing that was nice about this was that the Atari OS had
low-memory shadows of many of the important registers, so you could modify
the hardware registers in a DLI knowing it would be reset during the
vertical blank.
> Well... as far as I know, the Atari ST didn't have that text mode either.
> And on the Amiga the mouse pointer was represented by a sprite, not by
> re-writing the bitmap as it was done on the Atari ST, and as it's still
done
> on the PC's and Mac's today.
Actually, most modern PC video cards have hardware support for the mouse
cursor. With a good video driver, the only time you draw it directly is if
you are doing multicolored or animated cursors. I'm not sure about the Mac,
although modern incarnations are using the same video chips as many PCs.
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