Движение тела по окружности

//---------------------------------------------------------------------------
 
#include <vcl.h>
#include "math.h"
#pragma hdrstop
 
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
int radius = 40;
int posX = 650;
int posY= 350;
int x1 = 640;
int y1 = 290;
int x2 = 660;
int y2 = 310;
int a = 0;
int A = 20;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
 Refresh();
 a = a+1;
x1 = x1 + (20+40*cos(a/180));
x2 = x2 + (20+40*cos(a/180));
y1 = y1 + (20+40*sin(a/180));
y2 = y2 + (20+40*sin(a/180));
 
 
Canvas->Ellipse(TRect(posX-radius, posY-radius, posX+radius, posY+radius));
Form1->Canvas->Rectangle(x1, y1, x2, y2);
}
 
//---------------------------------------------------------------------------
 
void __fastcall TForm1::PaintBox1Click(TObject *Sender)
{
 
Canvas->Ellipse(TRect(posX-radius, posY-radius, posX+radius, posY+radius));
 
Form1->Canvas->Rectangle(x1, y1, x2, y2);
 
}
//---------------------------------------------------------------------------

//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop
 
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
  DoubleBuffered = 1;
  Timer1->Interval = 100;
}
//---------------------------------------------------------------------------
void rectangle(TCanvas *canvas, TColor pen_color, TColor brush_color, TPoint center, int width, int height, double angle)
{
  angle *= M_PI/180;
  canvas->Pen->Color = pen_color;
  canvas->Brush->Color = brush_color;
  int r = sqrt(width * width / 4 + height * height / 4);
  double angle2 = atan(1.*height / width);
  canvas->MoveTo(center.x - r*cos(angle2 + angle), center.y + r*sin(angle2 + angle));
  canvas->LineTo(center.x + r*cos(angle2 - angle), center.y + r*sin(angle2 - angle));
  canvas->LineTo(center.x + r*cos(angle2 + angle), center.y - r*sin(angle2 + angle));
  canvas->LineTo(center.x - r*cos(angle2 - angle), center.y - r*sin(angle2 - angle));
  canvas->LineTo(center.x - r*cos(angle2 + angle), center.y + r*sin(angle2 + angle));
  canvas->FloodFill(center.x, center.y, canvas->Pixels[center.x][center.y], fsSurface);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
  Refresh();
  static double angle = 1;
  double angle2, x = ClientWidth/2, y = ClientHeight/2, radius = 25, period = 10, size = 150;
  Canvas->Brush->Color = clRed;
  Canvas->Ellipse(x - radius, y - radius, x + radius, y + radius);
  angle--;
  angle2 = angle * M_PI / 180;
  rectangle(Canvas, clBlack, clBlue, TPoint(x-(radius+size/2)*cos(angle2*period), y+(radius+size/2)*sin(angle2*period)), size, size, angle*period);
}