>
> >CLC
> >ADC #252 ;If 0 <= A <= 3, the carry will now be clear.
You can save two cycles by:
ADC #251 ; if MissileY >= ScanLine, carry is set, so adjust by 1
I missed the original conversation, but you're probably aware that
AND #$FC ; If 0 <= A <= 3, the Z flag is now set.
PHP ;Plug it into ENABL.
is what Combat does, but it's limited to powers of 2 for the missile
height (its missiles are 2 high so use AND #$FE.)
If you're using a Supercharger and can afford the RAM (if cycles are
incredibly hard to come by compared to memory):
LDX ScanLine
LDA MissileEnableData,X
STA ENAM1
which would also allow missiles to be enabled/disabled in multiple
locations on the screen.
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