Re: [stella] Maze Craze and 650x

Subject: Re: [stella] Maze Craze and 650x
From: "Thomas Jentzsch" <tjentzsch@xxxxxx>
Date: Wed, 22 Aug 2001 12:53:32 +0200
Erik Mooney wrote:
> The Kernel# labels vary the position of the STA RESP0 by equal to
> or less than 15 pixels between them, so you can use HMOVE to get
> the object to any position on the screen.

> So you've positioned your object by using lots and lots of ROM, but
> only 28 cycles all told (including the last HMOVE).  Much less than using
> a full 76 cycle scanline.

If think, you will either need more than 11 routines for that or need some extra cycles, because the writes to RESP0 will not automatically fit into the other code.

Another approach to save cycles, that I learned from Bob's code (used in River Raid too), is to divide the positioning into 2 (or more) parts (left or right positioning, used in Thrust of course:), but that won't help here.

> Is this feasible?  Has it already been done anywhere?

It sounds possible to me, but not a simple task, because of the synchronization with the playfield writes. I haven't heard of that solution before, maybe it turns out to be to sophisticated. Good luck!

Have fun!
Thomas Jentzsch         | *** Every bit is sacred ! ***
tjentzsch at web dot de |

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