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This commit is contained in:
James Gregory 2013-12-30 18:34:31 +11:00
commit 18011c595a
352 changed files with 6040 additions and 6040 deletions
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24
48-02.md
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@ -53,10 +53,10 @@
.code
public _FillPatternX
_FillPatternX proc near
push bp ;preserve caller’s stack frame
push bp ;preserve caller's stack frame
mov bp,sp ;point to local stack frame
sub sp,STACK_FRAME_SIZE ;allocate space for local vars
push si ;preserve caller’s register variables
push si ;preserve caller's register variables
push di
cld
@ -123,8 +123,8 @@
sub cx,ax
shr cx,1
shr cx,1 ;# of addresses across rectangle to fill - 1
jnz MasksSet ;there’s more than one pixel to draw
and bh,bl ;there’s only one pixel, so combine the left-
jnz MasksSet ;there's more than one pixel to draw
and bh,bl ;there's only one pixel, so combine the left-
; and right-edge clip masks
MasksSet:
mov ax,[bp+EndY]
@ -141,27 +141,27 @@
FillRowsLoop:
mov cx,[bp+RectAddrWidth] ;width across - 1
mov al,es:[si] ;read display memory to latch this scan
; line’s pattern
; line's pattern
inc si ;point to the next pattern scan line, wrapping
jnz short NoWrap ; back to the start of the pattern if
sub si,4 ; we’ve run off the end
sub si,4 ; we've run off the end
NoWrap:
mov al,bh ;put left-edge clip mask in AL
out dx,al ;set the left-edge plane (clip) mask
stosb ;draw the left edge (pixels come from latches;
; value written by CPU doesn’t matter)
; value written by CPU doesn't matter)
dec cx ;count off left edge address
js FillLoopBottom ;that’s the only address
js FillLoopBottom ;that's the only address
jz DoRightEdge ;there are only two addresses
mov al,00fh ;middle addresses are drawn 4 pixels at a pop
out dx,al ;set the middle pixel mask to no clip
rep stosb ;draw the middle addresses four pixels apiece
; (from latches; value written doesn’t matter)
; (from latches; value written doesn't matter)
DoRightEdge:
mov al,bl ;put right-edge clip mask in AL
out dx,al ;set the right-edge plane (clip) mask
stosb ;draw the right edge (from latches; value
; written doesn’t matter)
; written doesn't matter)
FillLoopBottom:
add di,[bp+NextScanOffset] ;point to the start of the next scan
; line of the rectangle
@ -172,10 +172,10 @@
mov al,0ffh ; which selects all bits from the CPU
out dx,al ; and none from the latches (the GC
; Index still points to Bit Mask)
pop di ;restore caller’s register variables
pop di ;restore caller's register variables
pop si
mov sp,bp ;discard storage for local variables
pop bp ;restore caller’s stack frame
pop bp ;restore caller's stack frame
ret
_FillPatternX endp
end