function CopyClipToBuf(DC: HDC; Left, Top,
 Width, Height: Integer; Rop: LongInt;
 var CopyDC: HDC;
 var CopyBitmap: HBitmap): Boolean;
var
 TempBitmap: HBitmap;
begin
 Result := False;
 CopyDC := 0;
 CopyBitmap := 0;
 if DC <> 0 then
 begin
 CopyDC := CreateCompatibleDC(DC);
 if CopyDC <> 0 then
 begin
 CopyBitmap := CreateCompatibleBitmap(DC,
 Width, Height);
 if CopyBitmap <> 0 then
 begin
 TempBitmap := CopyBitmap;
 CopyBitmap := SelectObject(CopyDC,
 CopyBitmap);
 Result := BitBlt(CopyDC, 0, 0,
 Width, Height, DC,
 Left, Top, Rop);
 CopyBitmap := TempBitmap;
 end;
 end;
 end;
end;

function CopyBufToClip(DC: HDC; var CopyDC: HDC;
 var CopyBitmap: HBitmap; 
 Left, Top, Width, Height: Integer;
 Rop: LongInt; DeleteObjects: Boolean): Boolean;
var
 TempBitmap: HBitmap;
begin
 Result := False;
 if (DC <> 0) and
 (CopyDC <> 0) and
 (CopyBitmap <> 0) then
 begin
 TempBitmap := CopyBitmap;
 CopyBitmap := SelectObject(DC, CopyBitmap);
 Result := BitBlt(DC, Left, Top,
 Width, Height, CopyDC,
 0, 0, Rop);
 CopyBitmap := TempBitmap;
 if DeleteObjects then
 begin
 DeleteDC(CopyDC);
 DeleteObject(CopyBitmap);
 end;
 end;
end;

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