Re: A86: [ot] any ideas on an algo for this game?


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Re: A86: [ot] any ideas on an algo for this game?




Since everyone's plugging their grayscale routines, I'd like to suggest
the one I used in FD2...

There are some disadvantages I guess...  it uses af' and c', the two
planes need to be right next to each other (such as $f800 and $fc00), so
you might need to move the stack.  Also it doesn't handle the keyboard,
but real programs read the keys through port 1 anyway :)

The contrast stuff was just thrown in to save a few bytes in my code... 
can be taken out.  (page) should be set to the upper byte of the lower
plane ($f8 in the above example).

intcode:	
	ex af,af'		
	ld a,%00001000		
	out (3),a		
	ld a,%00001011		
	out (3),a		
	exx
	ld a,($c008)		
	out (2),a	
	ld a,(page)		
	srl c
	jr nz,cnotzero
reloadc:		
	ld c,%00011100	;2:3 mixing, change to %00000101 for 1:2
cnotzero:							
	jr nc,nopageflip
	add a,$04
nopageflip:	
	out (0),a
	ex af,af'
	exx
	ei								
	ret


matt wrote:
> 
> after reading this i watched the worms carefully and this seems like the way
> to go. anyone know whats the best 4 level grayscale out there?
> peace



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