title: What parameters can I use with Unity Input.getAxis?
body: <p>Unity <a href="http://docs.unity3d.com/ScriptReference/Input.GetAxis.html"><code>.getAxis(string name)</code></a> seems to return the thought offset generated by user input (arrows, mouse or even joystick). The return values is conveniently in interval of <code>&lt;-1; 1&gt;</code> except for the mousewheel.  </p>
  
  <p>From various code samples I can see many ways of getting input, but there seems to be no actual name/input list. In my case, I want to enable zoom using wheel or <kbd>PgUp</kbd> and <kbd>PgDn</kbd>. Wheel code looks like this:</p>
  
  <pre><code>movement.y -= ResourceManager.ScrollSpeed * Input.GetAxis("Mouse ScrollWheel");
  </code></pre>
  
  <p>But what for page down and page up? And, in general, how can I know which names to use in this method?</p>