Misc/abrash-black-book
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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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14
48-04.md
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@ -61,10 +61,10 @@
.code
public _CopyScreenToScreenX
_CopyScreenToScreenX 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
push ds
@ -112,8 +112,8 @@
sub cx,ax
shr cx,1
shr cx,1 ;# of addresses across rectangle to copy - 1
jnz MasksSet ;there’s more than one address to draw
and bh,bl ;there’s only one address, so combine the
jnz MasksSet ;there's more than one address to draw
and bh,bl ;there's only one address, so combine the
; left- and right-edge clip masks
MasksSet:
mov ax,[bp+SourceEndY]
@ -148,7 +148,7 @@
movsb ;copy the left edge (pixels go through
; latches)
dec cx ;count off left edge address
js CopyLoopBottom ;that’s the only address
js CopyLoopBottom ;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
@ -170,10 +170,10 @@
out dx,al ; and none from the latches (the GC
; Index still points to Bit Mask)
pop ds
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
_CopyScreenToScreenX endp
end