Re: [pygame] Pygame comparison to BlitzBasic

["Martin Sandin" <msandin@hotmail.com>]

> and with a much bigger experience in gaming API maybe... the chap who did
> that was already making his big bucks on the Amiga platform (well renown
> for its prowess (i would not here explain how it was possible to display
> 32000 colors
> on a 2 bitplan screen :))
> 

Oh, oh, I'll do it!=) The copper, oh yah, writing copper programs was so much fun=) Anyone who has made bouncing copper bars and scrolling vertical split screen games learns to appreciate the little bugger. You'd have the playing field setup in memory and the status bar at a different place and then you'd make a small copper program to do this: (the copper is tied to to the CRT beam so it only need three(?) commands, wait for a certain scanline, load hardware register, and skip command).

1) load the address of the top of the first players "slice of the ingame screen" into the hardware register for the memory fetch address
2) wait for a little above middle of screen
3) load the address if the top of the status bar
4) wait 20 scan lines or so (status bar height)
5) load the address of the top of the second players "slice"
6) wait for end of screen

Really useful=) The players will be looking at the same screen memory twice if their slices overlap. And with the color palette for the 16 or so available colors residing in hardware registers as well it becomes really easy to make gradients in the background by utilizing one and only one "palette color" by changing that same color all the time =) Most Amiga games seemed to employ this technique.

Sometimes I miss the neat things the Amiga's unique hardware allowed to be done easily =) Certainly not everything has become easier to do just because computers have gotten faster and languages higher level.


-
Martin Sandin - Still here =)
http://come.to/vague
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