title: Detected Lines Angle in EmguCV
body: <p>i used image.HoughLine to find line in my image. i want to know the angle of each line. so i tried :</p>
  
  <pre><code>double deltaY = line.P2.Y - line.P1.Y;
  double deltaX = line.P2.X - line.P1.X;
  double angle;
  if (deltaX != 0)
          angle = Math.Atan2(deltaY, deltaX);
  else
          angle = 90;
  </code></pre>
  
  <p>but , it returns 0 and -1 , while the lines in image at least have 15 degree . ( i rotated the image myself ).</p>
  
  <p>what's wrong? and what is Direction in LineSegment2D class, could it help ?</p>