Re: [stella] DD build 8

Subject: Re: [stella] DD build 8
From: "TwoHeaded Software" <adavie@xxxxxxxxxxxxx>
Date: Mon, 22 Oct 2001 18:21:38 +1100
DD still doesn't work under Z26.  I think Thomas (or maybe Eckhard) posted
the solution earlier.
Andrew Davie, TwoHeaded Software

----- Original Message -----
From: "Glenn Saunders" <cybpunks2@xxxxxxxxxxxxx>
To: <stella@xxxxxxxxxxx>
Sent: Monday, October 22, 2001 5:17 PM
Subject: [stella] DD build 8

> Okay, I succeeded in implementing Thomas' sprite logic routine into Death
> Derby.  (I also threw in the VDEL code from Roger's recent post).
> More of an achievement as far as original code goes was getting the sprite
> rotation system working.  For someone new to assembly language, it's
> exciting seeing your new original code actually work, even if it's a
> trivial thing.  I've got the code that determines wether or not to do the
> hardware sprite flip, and the data laid out pointing to all the different
> frames in a complete rotation, and it worked.  Although in this demo the
> cars are just statically pointing towards eachother, they are both using
> the same frame of animation, with the flip turned-on on the right.  So I
> could write a routine that increments a simple counter 0-15 and get the
> cars to smoothly rotate around clockwise, using only 9 frames of data.
> I thought about using different types of car shapes but it was so hard to
> maintain the image in the rotations that I'm sticking to one set for now.
> I also changed some colors around.  P0 has to be a different color from
> and the missiles will share the same colors as their players.  The PF can
> be white or grey on the black background.  Maybe in the end I'll do a
> missile command/centipede sort of thing and remap the palette into
> psychadelic colors if the game winds up having waves.  I always liked that
> style of color usage so common in the early days.
> The problem I have now is that the horizontal positioning routine I
> borrowed from Gunfight is not working properly.  I don't know what I'm
> doing wrong with it.  Manual, could you check it??  The players move in
> jumps when I change their start positions and if I make the players cross
> the screen flips out.
> I thought about using the recently posted table method, but I was too lazy
> to try to convert the code over.  I also don't know what I'm up to so far
> in actual ROM usage so it might be a bad idea to use the table method if
> the game's going to only be 4K.
> Also, I had a question about HMOVE lines.  It looks like I'm going to have
> to have HMOVE on either every line, or every other line, depending on the
> position of M0 and M1.  Every other if they are on the same line of the
> line-pair, and every line if they are on even/odd lines.  This is going to
> wind up wiping out the leftmost part of the safezone border line.  If I
> the ball priority above PF0 and PF1 couldn't I repaint it using the
> ball?  And then I could just keep M0 to the right of the HMOVE lines
> in black, correct?  The HMOVE lines are narrow enough, I hope, to keep M0
> from being affected by them.
> Glenn Saunders - Producer - Cyberpunks Entertainment
> Personal homepage:
> Cyberpunks Entertainment:

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