> Here's another, very simple too... never JMP unless you can't really avoid
> it. If you know that some status bit is always 0 or 1 at that point, use a
> branch instruction instead, to save a byte and some cycles. And what if
> the brach is out of range? Easy: spend a couple of hours re-arranging your
> time-sensitive code to make that BNE possible. It happened to me, and might
> happen to you too... :)
I'd extend that rule to JSR's, if it gets tight enough.
> BitmapShape:
> .byte $AA
> .byte $23
> ZgyzLookupTable:
> .byte $00
> .byte $00
> .byte $01 ; <- end of BitmapShape
> .byte $01
> .byte $02
Formatting idea... this might clear things up.
> BitmapShape: ;BitmapShape:
> .byte $AA
> .byte $23
> ZgyzLookupTable: ; .byte $00 ;data duplicated in
> .byte $00 ; .byte $00 ;ZpyzLookupTable.
> .byte $00 ; .byte $01
> .byte $01
> .byte $01
> .byte $02
> Lots of graphics data can be "compacted" in this way. Also, I ended
> changing the design of some graphics so that I could compact them better,
> and save some more bytes... wicked!
I did this to "Dark Mage" but Greg never implemented it. I shaved TONS of
space off the fonts by using the Atari 800 font, which has a lot of room
for this kind of sharing. Never got to test it because my version of
DASM won't compile his code. I think I got the whole alphabet down to
like 126 bytes, using six-byte-high characters. Original prototypes
used a seven-byte-high font, and I could have compacted that too, by
borrowing from the Commodore 64 font.
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