procedure TForm1.Demo_TgtPDFCircleAnnot;
var
  gtPDFCircleAnnot1: TgtPDFCircleAnnot;
  gtPDFEngine1: TgtPDFEngine;
begin
  gtPDFEngine1 := TgtPDFEngine.Create(Nil);

  // Create a circle annotation
  gtPDFCircleAnnot1 := TgtPDFCircleAnnot.Create;
  gtPDFCircleAnnot1.BorderStyle := brDashed;
  // Set border dash pattern to 6-point dashes
  // and 2-point gaps
  gtPDFCircleAnnot1.BorderPattern := '6 2';
  // Set border to be "cloudy"
  gtPDFCircleAnnot1.Cloudy := True;
  // Set border cloudiness to maximum
  gtPDFCircleAnnot1.CloudIntensity := 2;

  gtPDFCircleAnnot1.BorderWidth := 4;
  gtPDFCircleAnnot1.InteriorColor := clRed;
  gtPDFCircleAnnot1.DifferRect := gtRect(0.5, 0.1, 0.2, 1);
  gtPDFCircleAnnot1.BorderColor := clGreen;

  gtPDFCircleAnnot1.Rect := gtRect(1, 2, 3, 4);
  gtPDFCircleAnnot1.Contents :=
    'Dashes are 6-points wide and gaps are 2-points wide';
  gtPDFCircleAnnot1.Title := 'Circle Annotation Demo';
  gtPDFCircleAnnot1.Subject := 'About border pattern';

  with gtPDFEngine1 do
  begin
    Preferences.ShowSetupDialog := False;
    Preferences.OpenAfterCreate := True;
    FileName := 'circle_annotation.pdf';

    BeginDoc;
    // Add caret annotation
    AddAnnotItem(gtPDFCircleAnnot1);
    EndDoc;
  end;
end;