GRPx questions

[+atari2600land]

Hi all. I am working on a game in assembly where I need to have (up to) 9 characters on the screen at the same time. And since Space Invaders did this (not to mention all the homebrew works, like bBlocks), I am fairly certain I can achieve this. But how?

 

I know that I can get two copies of the same sprite with NUSIZx. But I'm wondering if I can just set GRPx to 0, reset the counter used to draw them, and then start drawing them again and again for the desired 9 times I'd need to do this? By the way, they can all be the same sprite. They don't have to be different sprites. It's just going to be bats flapping their wings up and down, so it's nothing too fancy.

 

So I would need to use player 0 for the bats, and I'd also like to have player 1 free if possible.

[+atari2600land]

I've been working on this for 6 hours?!

Anyway, I did this. Nine bats with two frames of animation. I need a better bat sprite though. That thing on the bottom is Player0, while the bats are player 1.

[+SpiceWare]

MiniDig is useful for stuff like this. They have a link to info about the Multi-Sprite trick used in Galaxian.

 

http://www.qotile.net/minidig/tricks.html

[+atari2600land]

I'll let you guys look at what I'm trying to do. I'm trying to make the "lost" CCW game "Count's Castle." Things are going good so far, but if I have any questions, I'll need to ask before I begin pulling my hair out.

Here is a zip file containing .asm and .bin files.

I need new bat and Count sprites, though.

count6.zip

[Kiwi]

If count and the bats are not going to be meet up horizontally.  You could use P0 and P1 for the bats, and P0 and P1(extra color) for count by repositioning the sprite after the bats are drawn via set position routine, and HMOVE after setting the count x variable into the set position routine.  That way, you could have 6 bats a row up to 18 or more if you want more rows.