Улитка паскаля

uses GraphWPF;
const a=100;b=123;dt=0.1;n=12;dangle=pi/n*2;
function cx(t:Real):=a*cos(t)**2+b*cos(t);
function cy(t:Real):=a*cos(t)*sin(t)+b*sin(t);
begin
  var angle := 0.0;
  loop n do begin
    var t:=0.0;var(sina,cosa,x,y):=(sin(angle),cos(angle),cx(t),cy(t));
    MoveTo(Window.Center.X+cx(t)*cosa-cy(t)*sina,Window.Center.Y+cx(t)*sina+cy(t)*cosa);
    repeat t+=dt;LineTo(Window.Center.X+cx(t)*cosa-cy(t)*sina,Window.Center.Y+cx(t)*sina+cy(t)*cosa);until t>2*pi;
    angle+=dangle;
  end;
end.

uses GraphABC;
const a=100;b=123;dt=0.1;n=12;dangle=pi/n*2;
function cx(t:Real):=a*cos(t)**2+b*cos(t);
function cy(t:Real):=a*cos(t)*sin(t)+b*sin(t);
begin
  var angle := 0.0;
  loop n do begin
    var t:=0.0;var(sina,cosa,x,y):=(sin(angle),cos(angle),cx(t),cy(t));
    MoveTo(Window.Center.X+Trunc({cx(t)}x*cosa-{cy(t)}y*sina),Window.Center.Y+Trunc({cx(t)}x*sina+{cy(t)}y*cosa));
    repeat t+=dt;LineTo(Window.Center.X+Trunc(cx(t)*cosa-cy(t)*sina),Window.Center.Y+Trunc(cx(t)*sina+cy(t)*cosa));until t>2*pi;
    angle+=dangle;
  end;
end.