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Show text progressively as typed with a typewriter (horizontal/vertical)

01.01.2007
{
 To make this code to work you would need 2 images,
 one for the horizontal- and another for the vertical text.
}
 
// VerticalTypewriter ( <Text>, <Image to write to>, <Time to delay between every chars> )
procedure VerticalTypewriter(text: string; image: timage; delay: integer);
var
 x,y,i: integer;
begin
 image.Canvas.Refresh;
 application.ProcessMessages;
 y := 1;
 
 for i := 1 to length(text) do begin
  application.ProcessMessages;
  y := y+image.Canvas.TextHeight(text[i]);
  x := image.width div 2 - (image.Canvas.TextWidth(text[i]) div 2);
  image.Canvas.TextOut(x,y,text[i]);
  sleep(delay);
 end;
 
end;
 
// Horizontal Typewriter ( <Text>, <Image to write to>, <Time to delay between every chars>, <Space between chars>)
procedure HorizontalTypewriter(text: string; image: timage; delay, space: integer);
var
 x,y,i: integer;
begin
 image.Canvas.Refresh;
 application.ProcessMessages;
 x := 1;
 
 for i := 1 to length(text) do begin
  application.ProcessMessages;
  y := image.Picture.Height div 2 - (image.Canvas.TextHeight(text[i]) div 2);
  x := x+image.Canvas.TextWidth(text[i])+space;
  image.Canvas.TextOut(x,y,text[i]);
  sleep(delay);
 end;
 
end;
 
 
// Sample calls:
procedure TForm1.Button1Click(Sender: TObject);
begin
 //                  <text>          <image>  <delay>
 VerticalTypewriter('HELLO BIG-X',   image1,  100     );
end;
 
procedure TForm1.Button2Click(Sender: TObject);
begin
 //                    <text>         <image>  <delay>  <space>
 HorizontalTypewriter('Hello Big-X',  image2,  100,     1       );
end;

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