Scrolling with the F18A

[cbmeeks]

Is there a tutorial or source code available that would show me how to do smooth scrolling using the enhanced features of the F18A?  More specifically, scrolling like in Metroid or Kid Icarus that can be horizontal or vertical but not at the same time.  Something simple.

 

I'd prefer assembly so that I can learn it too (I'm pretty good at 6502 asm). 

 

Thanks!

Edited October 8, 2019 by cbmeeks

[+FarmerPotato]

I just studied this, with help from Rasmus. Go to the development thread. That's where you can find past discussion of scrolling.

 

Rasmus' scrolling demo is attached to the first post, along with other essentials like the spreadsheet of all the video registers.

 

Please post your followup questions on that thread, so others can benefit.

 

You are welcome to my source code for scrolling in sprtest.a99 (but not the graphics).  It is an early game-prototype that scrolls TL2 (foreground) over a 48x64 field in both directions, and a parallax backdrop (TL1) horizontally over 24x64.

 

To assemble my code, I use Windows, Cygwin, and xdt99. I edit the .a99 source files and type 'make'. Then I load the resulting .dsk file into JS99er.net (Classic99 is still great for debugging, but doesn't have as much F18A support.) I also use Magellan for graphics editing.