title: Setting color brightness on Linux/Xorg
body: <p>Is there any command (or API) to set X.Org/Linux color brightness?</p>
  
  <p>In other words, I need something as handy as the <a href="http://linuxcommand.org/man_pages/xgamma1.html" rel="nofollow noreferrer">xgamma</a> command but for changing RGB brightness <em>real-time</em>.</p>
  
  <p>Is this possibile?</p>