## Re: [stella] z-Axis Movement Programming Theory Sources?

 Subject: Re: [stella] z-Axis Movement Programming Theory Sources? From: KirkIsrael@xxxxxxxxxxxxx Date: 14 Oct 2003 11:58:55 -0000
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> > Any help with the theory would be appreciated!
>
> BTW: Did you ever check out "Racquetball"? It looks
> pretty similar to what you seem trying to achieve.

I was going to suggest the same thing, though I was
worried about sounding a discouraging note.
http://atariage.com/screenshot_page.html?SoftwareLabelID=389

Any, re: x/y/z... if I say z is into the screen
(which is not what the C=64 article starts with)
and IF you have your math so that 0,0 for X and
Y is at the center of the screen (which means you
and vertical positioning), then Z is a factor
between like .5 and 2 that you multiply X and Y
by... if the thingy is as far away as possible,
you multiply X and Y by .5, bringing the thing
closer to the center of the physical screen.
If the thing is as close as possible, you multiply
X and Y by 2, moving it away from the center of the
screen. If the thing is in the middle depth, you
multipy X and Y by 1, and it's about where it was
before.

Obviously, there are real world constraints, like
all the math will probably have to be integer and
what not, but you get the idea.

http://www.kisrael.com/viewblog.cgi?date=2001.03.02
shows it in actino, though I can't find the source
code at the moment (surprised I didn't post it
there)

Though it sounds like you have some general kernal
and screendrawing issues that you really need to
nail down first, before diving too much into the
3D stuff.

Good luck!

PS THE most amazing 3D game on the 2600 is Battlezone.
The way you can hear a shot fired off screen, throw it
into reverse, and watch the bullet zoom in front of you
is amazing.  Then again, I'm even amazed at things like
circular radar screens with a sweeping hand. Actually,
in some ways I'm more amazed by that. How *do* you do
something like that?

--
KirkIsrael@xxxxxxxxxxxxx    http://kisrael.com
"Stupid people see beauty only in beautiful things."