CONST 
  StickWidth = 2, 
  StickColor = Color.Red, 
  CircleWidth = 2, 
  CircleColor = Color.Black;

PROC Stick(a, b, c) IS 
  IF 
    R2.Length(a) < 5000 -> 
      SAVE PS IN 
        PS.MoveTo(a); 
        PS.LineTo(b); 
        PS.LineTo(c); 
        PS.SetWidth(StickWidth); 
        PS.SetColor(StickColor); 
        PS.Stroke() 
      END | SKIP 
  FI 
END;

UI PointTool(Stick);

PROC Circ(a, b) IS 
  IF 
    R2.Length(R2.Minus(a, b)) < 1000 -> 
      SAVE PS IN 
        Circle.Draw(a, b); 
        PS.SetWidth(CircleWidth); 
        PS.SetColor(CircleColor); 
        PS.Stroke() 
      END | SKIP 
  FI 
END;

UI PointTool(Circ);

PROC Circum(a, b, c) IS 
  IF 
    VAR d ~ (0, 0) IN 
      (a, d) CONG (b, d) AND (b, d) CONG (c, d) -> 
        Circ(d, a) 
    END 
  FI 
END;

PROC Cmd0() IS 
  IF 
    VAR 
      ab ~ (-57.179592, -204.83449), ad = (81.03986, 47.784817), 
      bd = (-103.761314, 86.467766), ac = (20.44931, -62.9546), 
      bc = (-69.67913, -126.667694), cd ~ (155.1551, 32.270866) 
    IN 
      Geometry.Colinear(ab, ac, ad) AND 
      Geometry.Colinear(ab, bc, bd) AND 
      Geometry.Colinear(ac, bc, cd) AND 
      Geometry.Colinear(ad, bd, cd) -> 
        Stick(ab, ac, ad); 
        Stick(ab, bc, bd); 
        Stick(cd, ac, bc); 
        Stick(cd, ad, bd); 
        Circum(ab, ac, bc); 
        Circum(ab, bd, ad); 
        Circum(ac, ad, cd); 
        Circum(bc, bd, cd) 
    END 
  FI 
END;