paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-04-22 08:29:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

* read the planes in reverse order, so that less shift instructions are required in GetPixel16

Browse Source 
git-svn-id: trunk@40973 -
This commit is contained in:
nickysn 2019-01-21 16:09:13 +00:00
parent 33c330b3bc
commit b654c34d64
1 changed files with 16 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
packages/graph/src/msdos/graph.pp
View File

@ -1697,7 +1697,7 @@ end;
add si,[VideoOfs] { Point to correct page offset... }
mov dx,03ceh
mov ax,0004h
mov ax,0304h
out dx,ax
inc dx
@ -1707,40 +1707,37 @@ end;
sub cl,al
mov bl,cl
{ read plane 0 }
{ read plane 3 }
mov al,es:[si] { read display memory }
shr al,cl
and al,01h
mov ah,al { save bit in AH }
{ read plane 1 }
mov al,1 { Select plane to read }
out dx,al
mov al,es:[si]
shr al,cl
and al,01h
shl al,1
or ah,al { save bit in AH }
{ read plane 2 }
mov al,2 { Select plane to read }
out dx,al
mov al,es:[si]
shr al,cl
and al,01h
shl al,1
shl al,1
or ah,al { save bit in AH }
shl ah,1
or ah,al { save bit in AH }
{ read plane 3 }
mov al,3 { Select plane to read }
{ read plane 1 }
mov al,1 { Select plane to read }
out dx,al
mov al,es:[si]
shr al,cl
and al,01h
shl al,1
shl al,1
shl al,1
shl ah,1
or ah,al { save bit in AH }
{ read plane 0 }
mov al,0 { Select plane to read }
out dx,al
mov al,es:[si]
shr al,cl
and al,01h
shl ah,1
or ah,al { save bit in AH }
mov al,ah { 16-bit pixel in AX }