title: WebGL: canvas coordinates to 3d coords
body: <p>I am trying to find the "left" border of my WebGL view port because I would like to draw a number of debug information there. (an axis mini map like most modeling programs have)
  I certainly can get the width and height of the canvas containing the WebGL viewport.</p>
  
  <p>I would really like to know how I would go about calculating 2d canvas coordinates to 3d coordinates? What would be the best approach to find the left border in the 3d viewport?</p>
  
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  <p>Anyone looking into this should read
  <a href="http://webglfactory.blogspot.com/2011/05/how-to-convert-world-to-screen.html" rel="nofollow">http://webglfactory.blogspot.com/2011/05/how-to-convert-world-to-screen.html</a> or take a look at GluProject() and GluUnproject()</p>