Author: Tomas Rutkauskas 

How can I temporally turn off the Windows font anti-aliasing and turn it on after 
drawing?

Answer:

1   unit Unit1;
2   
3   interface
4   
5   uses
6     Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;
7   
8   type
9     TForm1 = class(TForm)
10      procedure FormCreate(Sender: TObject);
11      procedure FormDestroy(Sender: TObject);
12    private
13      SmoothFonts: Boolean;
14    public
15    end;
16  
17  var
18    Form1: TForm1;
19  
20  implementation
21  
22  {$R *.DFM}
23  
24  procedure TForm1.FormCreate(Sender: TObject);
25  begin
26    SystemParametersInfo(SPI_GETFONTSMOOTHING, 1, @SmoothFonts, 0);
27    if SmoothFonts then
28      SystemParametersInfo(SPI_SETFONTSMOOTHING, 0, nil, SPIF_UPDATEINIFILE);
29  end;
30  
31  procedure TForm1.FormDestroy(Sender: TObject);
32  begin
33    if SmoothFonts then
34      SystemParametersInfo(SPI_SETFONTSMOOTHING, 1, nil, SPIF_UPDATEINIFILE);
35  end;
36  
37  end.


Under Win95 it has only an effect if the Plus! Pack is installed (NT4 by default).