const
 PIDiv180 = 0.017453292519943295769236907684886;
procedure Rotate(RotAng: Double; x, y: Double; var Nx, Ny: Double);
var
 SinVal: Double;
 CosVal: Double;
begin
 RotAng := RotAng * PIDiv180;
 SinVal := Sin(RotAng);
 CosVal := Cos(RotAng);
 Nx := x * CosVal - y * SinVal;
 Ny := y * CosVal + x * SinVal;
end;

const

 PIDiv180 = 0.017453292519943295769236907684886;

procedure Rotate(RotAng: Double; x, y, ox, oy: Double; var Nx, Ny: Double);

begin

 Rotate(RotAng, x - ox, y - oy, Nx, Ny);

 Nx := Nx + ox;

 Ny := Ny + oy;

end;



procedure Rotate(RotAng: Double; x, y: Double; var Nx, Ny: Double);

var

 SinVal: Double;

 CosVal: Double;

begin

 RotAng := RotAng * PIDiv180;

 SinVal := Sin(RotAng);

 CosVal := Cos(RotAng);

 Nx := x * CosVal - y * SinVal;

 Ny := y * CosVal + x * SinVal;

end;