Genius G-Pen 560 on Xubuntu 14.10 via Aiptek driver

install xorg-server-aiptek driver.

create a settings file:

sudo vim /usr/share/X11/xorg.conf.d/70-aiptekmy.conf

Section "InputClass"                                                           
    Identifier "pen"                                                           
    MatchProduct "Aiptek|AIPTEK|aiptek"                                        
    MatchDevicePath "/dev/input/event*"                                        
    Driver "aiptek"                                                            
    Option "SendCoreEvents" "true"                                             
    Option "USB" "on"                                                          
    Option "Type" "stylus"                                                     
    Option "Mode" "absolute"                                                   
    Option "zMin" "0"                                                          
    Option "zMax" "1023"                                                       
EndSection

Genius G-Pen 560 under Debian 7.6

Download https://launchpad.net/wizardpen sources.
in the README file there are instructions to install dependencies.
Do ./configure, sudo make install.

edit /usr/share/X11/xorg.conf.d/70-wizardpen.conf

Section "InputClass"
   Identifier "wizardpen"
   MatchIsTablet "on"
   MatchDevicePath "/dev/input/event*"
   MatchTag "wizardpen"
   Driver "wizardpen"
   Option               "TopX"          "185"
   Option               "TopY"          "372"
   Option               "BottomX"       "11811"
   Option               "BottomY"       "8793"
   Option               "TopZ"          "32"
EndSection

Restart and enjoy!

Opengl 2d

https://www.mapbox.com/blog/drawing-antialiased-lines/