mirror of https://github.com/nmlgc/ReC98.git
29 lines
429 B
NASM
29 lines
429 B
NASM
; Generates a lookup table for flipping one byte, interpreted as a horizontal
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; line of 8 pixels in a single bitplane.
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; int DEFCONV hflip_lut_generate()
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proc_defconv hflip_lut_generate
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push di
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xor ax, ax
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mov di, offset hflip_lut
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xor dl, dl
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jmp short @@check
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@@outer:
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xor dl, dl
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mov cx, 8
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@@inner:
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rol al, 1
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rcr dl, 1
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loop @@inner
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@@check:
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mov [di], dl
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inc di
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inc al
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jnz short @@outer
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pop di
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ret
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endp_defconv
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