Re: [stella] Polar to Cartesian Co-Ordinate Converter

Subject: Re: [stella] Polar to Cartesian Co-Ordinate Converter
From: "Roger Williams" <mer02@xxxxxxxxxxxxx>
Date: Mon, 22 Oct 2001 18:40:37 -0700
> The trick with the overhead thing is determining which frame of rotation
> use, and how to handle the rotating playfield.

I'm not going to use the playfield *evil grin*

> I thought it would be cool to do a driving game where the car remained
> but the track scrolled _and_ rotated (unlike a River Raid/Spy Hunter deal
> where the sprite just slides back and forth and you are railed in by the
> width of the screen) but I don't think that could be done on the 2600, at
> least not without major flicker.

It will probably be an air-warfare game like a first person Jets from
The landscape will consist mostly of points of light.  You don't need a lot
points to convey the illusion of motion and rotation, and I have an idea for
putting a hell of a lot of them on the screen *evil grin*

> I think it might be possible to do an X/Y scrolling driving game where
> car _can_ rotate, though, albeit with crude X movement and simplified
> tracks.  Isn't the old arcade game Super Bug done like that?  It might be
> possible to do an APB sort of game that way.  Probably it would require a
> Supercharger or 16K+Superchip.

The trick in doing it in 4K is rendering enough detail to convey the
of motion over a large enough landscape in only 1K or so of landscape
definition.  You can get away with surprisingly few objects, especially if
they are sprites.  Any scheduling algorithm that can put 5 or 6 sprites on
the screen will get you in the game.

You could also do a nautical theme where the game challenge centers
on navigation.  That also gets you away from linear features as long
as you stay at sea...

Suffice it to say I think there is plenty of room for experimentation here.
Someone suitably motivated could probably make a highly playable game
out of the p2cdemo.  Has anyone ever done a circular shooter?

--Roger Williams

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