Pixelize

ADDITIONAL COMMENTS

INSTRUCTIONS

Pixel Stuff - convert ST style bitplanes to packed pixel format for the Falcon

Algorithm used is to shift bits out of planes and into packed pix register
one at a time, high bit first. 

Note: Don't do this with 1 bpp data, it wastes time & confuses things.

Pseudo-Code to convert 16 pixels (2 4 or 8 bpp) to packed pixels
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LOAD PLANES[1..NUMBITPLANES] WITH one bitplane word (16 bits) each 
						; (sequential out of memory) 
FOR k = 1 to (NUMBITPLANES/2)			; save every 32 bits of ppix

	FOR i = 1 to (32/NUMBITPLANES)		; create 32 bits of packedpixels
		FOR j = NUMBITPLANES downto 1	; Get MSB of the pixel first	
			LSL.L PLANE[j]		; shift bit left into X bit
			ROXL.L PACKEDPIX 	; Rotate X bit left into dest.
		ENDFOR j
	ENDFOR i

	SAVE PACKEDPIX				; save 32 bits of ppix
ENDFOR k
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