All: attempt for an OpenGL video output for OS X. Enable --macosx-opengl

 All: attempt for an OpenGL video output for OS X. Enable --macosx-opengl
 to give it a try (QT is the default method).
  + Known issues: no fullscreen yet, memory leaks, ugly code, ...
  + Known goodies: it's a few % faster than QT here (playing a DVD). If
      experienced OpenGL and Altivec programmers could have a look and
      give some advice, I guess the performance increase might become
      noticeable.