Как нарисовать звездное небо

private void drawStar( Point cord, Graphics g, int size )
{
    Random r = new Random( DateTime.Now.Millisecond );
    Color color = Color.FromArgb( r.Next( 0, 255 ), r.Next( 0, 255 ), r.Next( 0, 255 ) );
    g.DrawLine( new Pen( color ), cord.X - size, cord.Y, cord.X + size, cord.Y );
    g.DrawLine( new Pen( color ), cord.X, cord.Y - size, cord.X, cord.Y + size );
}
 
private void button1_Click( object sender, EventArgs e )
{
    Graphics g = pictureBox1.CreateGraphics();
    Size size = new Size( pictureBox1.Width - 4, pictureBox1.Height - 4 );
    Random r = new Random( DateTime.Now.Millisecond );
 
    for ( int i = 0; i < int.Parse( textBox1.Text ); i++ )
        drawStar( new Point( r.Next( 4, size.Width ), r.Next( 4, size.Height ) ), g, r.Next( 1, 4 ) );
}