Scrolling Weirdness

[+Random Terrain]

I was trying to see what was wrong with a program that somebody was working on and noticed something odd when using set kernel_options player1colors playercolors pfcolors.

 

When both sprites are on the screen, the bottom row gets weird stuff in it when scrolling:

 

 

scrolling_01.bin

 

scrolling_01.bas

[RevEng]

It looks like the issue dates back to the official 1.0.

 

No bright ideas yet. Clearly the timing is messed up in the last playfield line when scrolled, which narrows it down to either the pfcolor list crossing a page boundary, or some other kernel timing issue with those options and the last-line loop.

 

Gotta dig some more another day.

[+Gemintronic]

Yeah. In Bath Blast I'm pretty sure I adjusted the playfieldpos and turned down the number of playfield rows REAL low to save time - especially if you just need a big, checkered playfield.

[RevEng]

Ok, I tracked it down to a page-crossing in the player1color loading. I think it was just an oversight on batari's part, since the code that handles the rest of the PF lines has the same code as my fix.

 

Here's a copy of the kernel. I'll put it in a full bB distribution update this weekend or thereabouts.

 

std_kernel.asm

[+Random Terrain]

Thanks! No more scrolling weirdness:

 

scrolling_03.bin

 

scrolling_03.bas