playfieldpos safe for variable use in multi sprite kernel?

[+Gemintronic]

I'm making a 2 player co-op Adventure-esque game.  That kind of thing has the potential to use tons of variables especially if it has to track the world location, x/y coordinates and state of dragons, items, etc..

 

As far as I can tell the multi sprite kernel never used playfieldpos ($c3) as batari moved on to other things before adding scrolling.  The 1942 scrolling technique uses PF1pointer and PF2pointer seemingly leaving playfieldpos undisturbed.

 

Can it officially be said it's safe for use?  Or, is it in use by the kernel or other mini-kernels?

[+Karl G]

I hadn't noticed that before, but I think you are right that that variable is unused. I tried a "trap $c3" in the Stella debugger while playing 1942, and it was neither read from nor written to. You should likely be safe repurposing that variable.