This code will make the camera in a Vertical Level act like one found
in vertical segments of Mega Man or Super Mario Bros. 2
For this feature to work, the level header must indicate either "No Vertical Scrolling" or "No Horizontal or Vertical Scrolling".
In addition, the Starting FG position must not be 0, or else the player will die when going down a screen.
Uses one byte of freeRAM (default $5E, which is unused in vertical levels).
Some stuff though:
- I personally don't think that CheckMario should be made a JSR-able subroutine since it's only called once in the code.
- Maybe you could add a check to see if verticall scroll is enabled, so the code always returns.
I feel like this would have more utility as a patch, too. But that's not an issue, really.