Re: [stella] Color & drawing limitations questions

Subject: Re: [stella] Color & drawing limitations questions
From: Glenn Saunders <krishna@xxxxxxxxxxxxxx>
Date: Thu, 18 Mar 1999 08:44:47 -0800
At 04:41 PM 3/19/99 +0100, you wrote:
>The TIA uses the graphics and colour values that are in the TIA registers
>when it's time to draw an object. So if you manage to change the colour
>and/or the graphics between two copies of a sprite, the TIA will display
>two different looking sprites in that scanline.

Which games out there manage to change the color of a sprite clone in the
same scanline?

Is this how Klax has all those colors for its bricks in one scanline?

>If you mean independently moving objects, then there are only the
>two player graphics, the two missiles and the ball.

Which means, theoretically, if each position register were changed each
scanline, thus with the illusion of 5 independent objects (slivers) per
scanline, that would amount to (200 * 5) 1,000 independently moving
objects!  If you enable sprite cloning, then you'll have groups of two or
three of these per scanline.  Therefore this tiny number of sprites can
pretty much fill the screen with pixels (at least when you implement
flicker routines).  Hence, you have games like Suicide MIssion or Stargate
which do almost all its painting with the sprites.

>For the background you can only change the colour, but the playfield
>has 2*20 pixels (with a width of four normal pixels). If you manage
>to change the three playfield registers during display, you can get
>full 40 pixels. The playfield can have the same colour as the ball,
>or the left half of the playfield has the same colour as player0
>while the right half shares a colour with player1.

How many playfield color changes can one manage in one scanline?

== Glenn Saunders  --3D Graphics / Videography / Web development--        ==
== krishna@xxxxxxxxxxxxxxx ==
== Stella@20 video page

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