procedure TForm1.PaintBox1Paint(Sender: TObject);
var
LCanvas: TCanvas;
begin
LCanvas := TPaintBox(Sender).Canvas;
LCanvas.Ellipse(100,100,400,400);
// ...
procedure TForm1.StrichClick(Sender: TObject);
var Radi, Gradi : extended ;
Pi: extended ;
begin
canvas.MoveTo(280,280);
canvas.lineto(280,125);
// ...
[/DELPHI]
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