CTRLPF Per Player?

[Cybearg]

So I'm in a situation where I'd like one player to move behind the playfield while another player moves in front of the playfield. Is there any modification that can be made (not worried if it costs extra memory) to the kernel to allow for this?

[+Random Terrain]

Did you check out the related links here:

 

randomterrain.com/atari-2600-memories-batari-basic-commands.html#ctrlpf

 

Might be something similar to what you want there.

[+SpiceWare]

CTRLPF = Control PlayField. If the above/below setting was per player it would be controlled via something like one of the unused bits (D7, D6 or D3) found in NUSIZ0 and NUSIZ1.

 

There is a way around it, but it will use a lot of RAM and CPU. You'd have to define the "behind playfield" player's graphic data to be stored in RAM, then you'd have to manually zero out any bits that would be blocked by a playfield pixel.

Edited July 15, 2013 by SpiceWare

[Cybearg]

CTRLPF = Control PlayField. If the above/below setting was per player it would be controlled via something like one of the unused bits (D7, D6 or D3) found in NUSIZ0 and NUSIZ1.

 

There is a way around it, but it will use a lot of RAM and CPU. You'd have to define the "behind playfield" player's graphic data to be stored in RAM, then you'd have to manually zero out any bits that would be blocked by a playfield pixel.

 

Thanks, this is the response I was looking for, unfortunate as it may be. Thanks for letting me know.

[freshbrood]

One quick and dirty way to achieve this illusion would be to constantly leave both players in front of the playfield, but to change all the colors of the player "behind" the playfield to the same colors as the playfield. This would essentially make it "disappear" while behind it.