Int Classify(int sx,int sy,int kx,int ky,int px,int py)

{

int tx,ty,Tpx,Tpy;

tx = kx - sx;

ty = ky - sy;

Tpx = px - sx;

Tpy = py - sy;

float s = tx*Tpy-ty*Tpx;

if(s > 0.0)return LEFT;

if(s < 0.0)return RIGHT;

return 0;

}

Void __fastcall tForm1::Timer1Timer(tObject *Sender)

{

int a,b;

TRect r;

r.top = 0;

r.left = 0;

r.right = Image1->Width;

r.bottom = Image1->Height;

Image1->Canvas->Brush->Color = clBlack;

Image1->Canvas->Pen->Color = clGreen;

Image1->Canvas->FillRect(r);

Image1->Canvas->Ellipse(1, 1, Image1->Width-1, Image1->Height-1);

Image1->Canvas->Ellipse(Image1->Width/4, Image1->Height/4, 3*Image1->Width/4, 3*Image1->Height/4);

Image1->Canvas->MoveTo(Image1->Width/2,0);

Image1->Canvas->LineTo(Image1->Width/2,Image1->Height);

Image1->Canvas->MoveTo(0,Image1->Height/2);

Image1->Canvas->LineTo(Image1->Width,Image1->Height/2);

Image1->Canvas->MoveTo(Image1->Width/2,Image1->Height/2);

X = COS[Angle];

Y = SIN[Angle];

Image1->Canvas->Pen->Color = clLime;

Image1->Canvas->LineTo(X,Y);

for(int i = 0;i < 2;i++)

{

Sam[i].move();

if(Sam[i].Xpos > Image1->Width || Sam[i].Xpos < 0)

Sam[i].sx = -Sam[i].sx;

if(Sam[i].Ypos > Image1->Height || Sam[i].Ypos < 0)

Sam[i].sy = -Sam[i].sy;

Image1->Canvas->Pixels[Sam[i].Xpos][Sam[i].Ypos] = clRed;

if(Angle >= 0 && Angle <= 180)

{

a = Classify(Image1->Width/2,Image1->Height/2,X,Y,Sam[i].Xpos,Sam[i].Ypos);

b = Classify(Image1->Width/2,Image1->Height/2,oldX,oldY,Sam[i].Xpos,Sam[i].Ypos);

if(a == RIGHT && b == LEFT)

{

Sam[i].TX = Sam[i].Xpos;

Sam[i].TY = Sam[i].Ypos;

Sam[i].count = 7;

}

}

else

{

a = Classify(Image1->Width/2,Image1->Height/2,X,Y,Sam[i].Xpos,Sam[i].Ypos);

b = Classify(Image1->Width/2,Image1->Height/2,oldX,oldY,Sam[i].Xpos,Sam[i].Ypos);

if(a == RIGHT && b == LEFT)

{

Sam[i].TX = Sam[i].Xpos;

Sam[i].TY = Sam[i].Ypos;

Sam[i].count = 7;

}

}

if(Sam[i].count!=0)

{

Sam[i].count--;

Image1->Canvas->Ellipse(Sam[i].TX,Sam[i].TY,Sam[i].TX+Sam[i].count,Sam[i].TY+Sam[i].count);

}

}

oldX = X;

oldY = Y;

Angle+=5;

if(Angle >= 360)Angle = 0;

sprintf(buf,"%f",Sam[1].Xpos);

Edit6->Text = buf;

sprintf(buf,"%f",Sam[1].Ypos);

Edit8->Text = buf;

sprintf(buf,"%f",Sam[0].Xpos);

Edit7->Text = buf;

sprintf(buf,"%f",Sam[0].Ypos);

Edit9->Text = buf;

}

//---------------------------------------------------------------------------

Void __fastcall tForm1::FormClose(tObject *Sender, tCloseAction &Action)

{

Timer1->Enabled = false;

}

//---------------------------------------------------------------------------

Void __fastcall tForm1::Edit1Change(tObject *Sender)

{

Speed = atoi(Edit1->Text.c_str());

if(Speed < 0 || Speed > 10)

Edit1->Text = "";

else

Timer1->Interval = Speed*1000/360;

}

//---------------------------------------------------------------------------

Void __fastcall tForm1::Edit2Change(tObject *Sender)

{

Sam[0].kx = atof(Edit2->Text.c_str());

}

//---------------------------------------------------------------------------

void __fastcall TForm1::Edit4Change(TObject *Sender)

{

Sam[0].Speed = atof(Edit4->Text.c_str());

}

//---------------------------------------------------------------------------

void __fastcall TForm1::Edit3Change(TObject *Sender)

{

Sam[1].kx = atof(Edit3->Text.c_str());

}

//---------------------------------------------------------------------------

void __fastcall TForm1::Edit5Change(TObject *Sender)

{

Sam[1].Speed = atof(Edit5->Text.c_str());

}

//---------------------------------------------------------------------------