mac-rom/QuickDraw/PictUtilities/puMedian.a
Elliot Nunn 4325cdcc78 Bring in CubeE sources
Resource forks are included only for .rsrc files. These are DeRezzed into their data fork. 'ckid' resources, from the Projector VCS, are not included.

The Tools directory, containing mostly junk, is also excluded.
2017-12-26 09:52:23 +08:00

163 lines
5.7 KiB
Plaintext

;
; File: puMedian.a
;
; Contains: Assembly routines for the median color finding algorithm for the picture utilities package.
;
; Written by: Dave Good. Some ideas stolen from Konstantin Othmer and Bruce Leak. Algorithm by Keith McGreggor.
;
; Copyright: © 1990 by Apple Computer, Inc., all rights reserved.
;
; Change History (most recent first):
;
; <6> 9/21/90 DDG Made changes from code review. Saved a few bytes of code.
; <5> 8/16/90 DDG Added and cleaned up some comments.
; <4> 8/1/90 DDG Changed the dispatch selector to go by ones instead of twos.
; <3> 7/30/90 DDG Adding a dispatch routine to support the generic colorPickMethod
; model.
; <2> 7/29/90 DDG Fixed header.
; <1> 7/29/90 DDG First checked in using new structure.
;
; To Do:
;
MACHINE MC68000
CASE OBJ
;¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥
BoxInfo RECORD 0
count ds.w 1
minRed ds.w 1
maxRed ds.w 1
minGreen ds.w 1
maxGreen ds.w 1
minBlue ds.w 1
maxBlue ds.w 1
totalRed ds.l 1
totalGreen ds.l 1
totalBlue ds.l 1
padding1 ds.l 1
padding2 ds.w 1
sizeofBoxInfo
ENDR
;¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥
;¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥
MedianDispatch PROC EXPORT
IMPORT INITMEDIANMETHOD
IMPORT RECORDMEDIANCOLORS
IMPORT CALCMEDIANTABLE
IMPORT KILLMEDIANMETHOD
lsl.l #2,D0
jmp dispatchTable(D0.w) ; jump into jump table
dispatchTable
jmp INITMEDIANMETHOD ; selector 0
jmp RECORDMEDIANCOLORS ; selector 1
jmp CALCMEDIANTABLE ; selector 2
jmp KILLMEDIANMETHOD ; selector 3
ENDPROC
;¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥
;
; This routine scans thru all the boxes in the passed array (boxInfoPtr), checking to see if their count is
; greater than zero. If it is, then we have a color to return, so for each component, we divide the total by
; the number of colors in this box to get the average component, then we smear the component out to fill a
; full 16-bit range for the color table. If the count for a particular color is zero, then we return black for
; that entry in the color table. Note that this will never happen until we have reached the end of the filled
; boxes, so at that point all we really want to do is fill the rest of the returned color table with black.
;
FillMedianTable PROC EXPORT
;----------------------------------------------------------------------------------------------------
boxInfoPtr EQU A0
resultPtr EQU A1
colorsRequested EQU D0
index EQU D1
temp EQU D2
five EQU D3
ten EQU D4
eleven EQU D5
component EQU D6
colorCount EQU D7
registersUsed REG D3-D7
regSize EQU 20
;----------------------------------------------------------------------------------------------------
;----------------------------------------------------------------------------------------------------
WITH BoxInfo
movem.l registersUsed,-(SP) ;save our work registers
move.l regSize+4(SP),boxInfoPtr ;copy our parameters into local variables (registers)
move.l regSize+8(SP),resultPtr
move.l regSize+12(SP),colorsRequested
clr.w index ;this is our counter for the colorÕs value.
moveq #5,five ;these are some constants that we want in registers
moveq #10,ten
moveq #11,eleven
bra.s @enter ;enter the loop properly for the DBRA instruction.
@loop move.w index,(resultPtr)+ ;set the value for the current entry and move ÒresultPtrÓ
addq.w #1,index ;..to the red component. Then increment ÒindexÓ
move.w count(boxInfoPtr),colorCount ;check the box count - if it is zero, then we are at
beq.s @empty ;..the end of the unique colors, so clear the entry.
move.l totalRed(boxInfoPtr),component ;get the total red value, divide by the color count,
bsr.s smearAndCopy ;..smear it into a 16-bit color and put it in ÒresultPtrÓ
move.l totalGreen(boxInfoPtr),component ;get the total green value, divide by the color count,
bsr.s smearAndCopy ;..smear it into a 16-bit color and put it in ÒresultPtrÓ
move.l totalBlue(boxInfoPtr),component ;get the total blue value, divide by the color count,
bsr.s smearAndCopy ;..smear it into a 16-bit color and put it in ÒresultPtrÓ
bra.s @next ;skip over the ÒclearÓ code.
@empty clr.l (resultPtr)+ ;clear both the red and green components at once
clr.w (resultPtr)+ ;clear the blue component
@next add.w #sizeofBoxInfo,boxInfoPtr ;move to the next box in the array
@enter dbra colorsRequested,@loop ;count down the number of colors and loop back
movem.l (SP)+,registersUsed ;restore our work registers
rts ;C will clean up the stack
ENDWITH
;----------------------------------------------------------------------------------------------------
smearAndCopy divu colorCount,component ;divide the total by the number of colors in this box.
lsl.w eleven,component ;smear the component into a 16-bit color, the same way
move.w component,temp ;..that quickdraw does.
lsr.w five,temp
or.w temp,component
move.w component,temp
lsr.w ten,temp
or.w temp,component
move.w component,(resultPtr)+ ;move the component into the result and increment the ptr
rts
;----------------------------------------------------------------------------------------------------
ENDPROC
;¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥¥
END