A common Atari trick is the rainbow color effect, which simply plugs the VCOUNT ($D40B) register into a color register, perhaps applying a counter (e.g., the faster RTCLOK register ($14)) to make it animated.
It would be nice to be able to DLI <addr> INTO <addr>, and perhaps do some simple math, e.g. for rainbow effect: DLI (&$D40B + &$14) INTO $D01A.
Operators like binary AND and OR would be useful as well. e.g., for a 'water' effect, the colors could animate within only the blue hues -- $80 through $8F -- like so: DLI (((&$D40B + &$14) & $0F) | $80) INTO $D01A or DLI (((&$D40B + &$14) & $0F) + $80) INTO $D01A.
A common Atari trick is the rainbow color effect, which simply plugs the
VCOUNT($D40B) register into a color register, perhaps applying a counter (e.g., the fasterRTCLOKregister ($14)) to make it animated.It would be nice to be able to
DLI <addr> INTO <addr>, and perhaps do some simple math, e.g. for rainbow effect:DLI (&$D40B + &$14) INTO $D01A.Operators like binary AND and OR would be useful as well. e.g., for a 'water' effect, the colors could animate within only the blue hues -- $80 through $8F -- like so:
DLI (((&$D40B + &$14) & $0F) | $80) INTO $D01AorDLI (((&$D40B + &$14) & $0F) + $80) INTO $D01A.