Sprite Scanlines

[SteveB]

Hi,

 

in order to write some generic sprite routines I want to store 4 bytes per sprite somewhere and wonder if it would be notable on any hardware when I use the first four bytes of the sprite itself. I newer saw them on my TV or any emulator I tried. 

(the four bytes are: y-pos of the actual player, length of the player and adress of the player-pattern).

 

Thanks

Steve

[sanny]

"sprite" is CBM-talk, the Atari has P/M (Player-Missiles) graphics.

 

So, P/Ms, the first four bytes are at the top of the screen. Might be ok to have "garbage" there, but I don't know if this is visible in some cases/TV-screens.

[phaeron]

ANTIC only issues P/M DMA cycles for scanlines 8-247, on either NTSC or PAL. This means that offsets $00-03 and $7C-7F in two-line resolution or $00-07 and $F8-FF in single-line resolution in each P/M slot are never read and can be reused.

 

[SteveB]

Perfect! Thank you, this even leaves room for an auto-motion feature someday.