unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, math, StdCtrls, ExtCtrls, XPMan;

type
  TForm1 = class(TForm)
    Timer1: TTimer;
    Timer2: TTimer;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    XPManifest1: TXPManifest;
    procedure Timer2Timer(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Timer1Timer(Sender: TObject);
    procedure FormClick(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  x:integer=50;
  y:integer=200;
  h:integer=50;
  w:integer=20;
  kx:real=1.0;
  ky:real=1.0;

  x2,y2,xx,yy,R:integer;
  A:real;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
Timer1.Enabled:=false;
Timer2.Enabled:=false;
Timer1.Interval:=50;
Timer2.Interval:=50;
Form1.Color:=clwhite;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
close
end;

procedure TForm1.FormClick(Sender: TObject);
begin
x:=50;
y:=200;
h:=50;
w:=20;
kx:=1.0;
ky:=1.0;
canvas.FillRect(canvas.ClipRect);
canvas.Ellipse(x-w, y-h, x+w, y+h);
Timer1.Enabled:=false;
Timer2.Enabled:=false;
canvas.Refresh;
end;

procedure TForm1.Timer1Timer(Sender: TObject);
var
w2,h2:integer;
begin

w2:=round(kx*w); h2:=round(ky*h);
 canvas.Pen.Color:=clwhite;
 canvas.Ellipse(x-w2, y-h2, x+w2, y+h2);
 canvas.Pen.Color:=clblack;

inc(x);
inc(y);
kx:=kx*0.99;
ky:=ky*0.99;

w2:=round(kx*w); h2:=round(ky*h);
canvas.Ellipse(x-w2, y-h2, x+w2, y+h2);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
Timer1.Enabled:=true;
end;

procedure TForm1.Button3Click(Sender: TObject);
var
t1, t2 :integer;
begin
canvas.FillRect(canvas.ClipRect);
xx:=100;
yy:=10;
canvas.MoveTo(xx,yy);
canvas.LineTo(200,140);

x2:=xx+(200-xx) div 2;
y2:=yy+(140-yy) div 2;

R:=round(sqrt(sqr(x2-xx)+sqr(y2-yy)));
A:=arccos((200-xx)/2/r);
Timer2.Enabled:=true;
end;

procedure TForm1.Timer2Timer(Sender: TObject);
var
t1, t2 :integer;
begin
canvas.Pen.Color:=clwhite;

t1:=round(r*cos(a));
t2:=round(r*sin(a));
canvas.MoveTo(x2-t1,y2-t2);
canvas.LineTo(x2+t1,y2+t2);

inc(x2);

a:=a+0.1;
t1:=round(r*cos(a));
t2:=round(r*sin(a));

canvas.Pen.Color:=clblack;
canvas.MoveTo(x2-t1,y2-t2);
canvas.LineTo(x2+t1,y2+t2);
end;

end.