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* split GetPixelX into strictly pascal and strictly asm version

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git-svn-id: trunk@41015 -
This commit is contained in:
nickysn 2019-01-23 13:37:06 +00:00
parent b48e901ed8
commit 44a193a027
1 changed files with 39 additions and 71 deletions
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110
packages/graph/src/msdos/graph.pp
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@ -2476,82 +2476,50 @@ const CrtAddress: word = 0;
{$undef asmgraph}
Function GetPixelX(X,Y: smallint): ColorType;
{$ifndef asmgraph}
var offset: word;
{$endif asmgraph}
function GetPixelX(X,Y: smallint): ColorType;
var offset: word;
begin
X:= X + StartXViewPort;
Y:= Y + StartYViewPort;
{$ifndef asmgraph}
offset := y * 80 + x shr 2 + VideoOfs;
PortW[$3ce] := ((x and 3) shl 8) + 4;
GetPixelX := Mem[SegA000:offset];
X := X + StartXViewPort;
Y := Y + StartYViewPort;
offset := y * 80 + x shr 2 + VideoOfs;
PortW[$3ce] := ((x and 3) shl 8) + 4;
GetPixelX := Mem[SegA000:offset];
end;
{$else asmgraph}
function GetPixelX(X,Y: smallint): ColorType;
begin
X := X + StartXViewPort;
Y := Y + StartYViewPort;
asm
{$ifndef fpc}
mov di,[Y] ; (* DI = Y coordinate *)
(* Multiply by 80 start *)
mov bx, di
shl di, 6 ; (* Faster on 286/386/486 machines *)
shl bx, 4
add di, bx ; (* Multiply Value by 80 *)
(* End multiply by 80 *)
mov cx, [X]
mov ax, cx
{DI = Y * LINESIZE, BX = X, coordinates admissible}
shr ax, 1 ; (* Faster on 286/86 machines *)
shr ax, 1
add di, ax ; {DI = Y * LINESIZE + (X SHR 2) }
add di, [VideoOfs] ; (* Pointing at start of Active page *)
(* Select plane to use *)
mov dx, 03c4h
mov ax, FirstPlane ; (* Map Mask & Plane Select Register *)
and cl, 03h ; (* Get Plane Bits *)
shl ah, cl ; (* Get Plane Select Value *)
out dx, ax
(* End selection of plane *)
mov es,[SegA000]
mov al, ES:[DI]
xor ah, ah
mov @Result, ax
{$else fpc}
push eax
push ebx
push ecx
push edx
push edi
movzx edi,[Y] ; (* DI = Y coordinate *)
(* Multiply by 80 start *)
mov ebx, edi
shl edi, 6 ; (* Faster on 286/386/486 machines *)
shl ebx, 4
add edi, ebx ; (* Multiply Value by 80 *)
(* End multiply by 80 *)
movzx ecx, [X]
movzx eax, [Y]
{DI = Y * LINESIZE, BX = X, coordinates admissible}
shr eax, 2
add edi, eax ; {DI = Y * LINESIZE + (X SHR 2) }
add edi, [VideoOfs] ; (* Pointing at start of Active page *)
(* Select plane to use *)
mov dx, 03c4h
mov ax, FirstPlane ; (* Map Mask & Plane Select Register *)
and cl, 03h ; (* Get Plane Bits *)
shl ah, cl ; (* Get Plane Select Value *)
out dx, ax
(* End selection of plane *)
mov ax, fs:[edi+$a0000]
mov @Result, ax
pop edi
pop edx
pop ecx
pop ebx
pop eax
{$endif fpc}
end;
mov di,[Y] ; (* DI = Y coordinate *)
(* Multiply by 80 start *)
mov bx, di
shl di, 6 ; (* Faster on 286/386/486 machines *)
shl bx, 4
add di, bx ; (* Multiply Value by 80 *)
(* End multiply by 80 *)
mov cx, [X]
mov ax, cx
{DI = Y * LINESIZE, BX = X, coordinates admissible}
shr ax, 1 ; (* Faster on 286/86 machines *)
shr ax, 1
add di, ax ; {DI = Y * LINESIZE + (X SHR 2) }
add di, [VideoOfs] ; (* Pointing at start of Active page *)
(* Select plane to use *)
mov dx, 03c4h
mov ax, FirstPlane ; (* Map Mask & Plane Select Register *)
and cl, 03h ; (* Get Plane Bits *)
shl ah, cl ; (* Get Plane Select Value *)
out dx, ax
(* End selection of plane *)
mov es,[SegA000]
mov al, ES:[DI]
xor ah, ah
mov @Result, ax
end;
end;
{$endif asmgraph}
end;
procedure SetVisualX(page: word);
{ 4 page supPort... }