TODO

* actor creation in a thread
* set_resize is working. correctly inject it into the on_resize event.
* math text/function visualization from sympy with Plot._pobjects
* * group/ungroup of actors
* server with ports open for websocket, running engine and taking commands
* progress bar
* streamable sources, e.g. with pyffmpeg
* slice viewer
* command menu for actors
* scene graph?
* view volume -> yt
* change transparency
* "action" wrapper for objects
* use function overwriting for e.g. draw functions, lighting condition changes
* colormaps. 3d to 1d. e.g. 256 colors, interpolate function inbetween
* labels (network), follow the camera when moving
* movie, ffmpeg
* save screenshot
* options for debug modus of opengl
* graphmenu actor. ortho mode, select options
* nx example working again
* world has a list of windows. (add window removal/close)
* camera logic, e.g. camerapath
* http://3dengine.org


a) call and interact from inside ipython 
b) support multiple windows (we crashing problem when closing a window)
c) have some general surface, volume, line, point, label,image, network actors
d) have menus as graphs
e) make animation easy
f) save screenshots and record video 
g) make creating a new actor very simple (just assumes some minor knowledge of opengl)
h) interacting with everything on the screen ( we have already a pickray system and some collision detection)
k) have some neat cameras

l) shaders, physics and machine learning additions

# need to install in fresh ubuntu
python-dev
cython 
freeglut3-dev (2.6.0-0ubuntu2)
glutg3 (3.7-25)
glutg3-dev (3.7-25)
libglut3 (3.7-25)