As i found several descriptions on the web how to do this, and only a mixture of them worked, here’s the a guide on setting up processing with opengl in eclipse. This assumes you have eclipse installed and downloaded the processing libraries already. Also I set it up on OSX, so paths might differ a bit on other systems:

1. go to your project properties -> build path -> add external jars, and add the following four:
   – /PATHTOPROCESSING/Resources/Java/core.jar
   – /PATHTOPROCESSING/Resources/Java/libraries/opengl/library/opengl.jar
   – /PATHTOPROCESSING/Resources/Java/libraries/opengl/library/jogl.jar
   – /PATHTOPROCESSING/Resources/Java/libraries/opengl/library/gluegen-rt.jar
2. still in the “add external jars” section, unfold jogl.jar, and add the native library location
   /PATHTOPROCESSING/Resources/Java/libraries/opengl/library/
3. create a new run configuration (run as … ), and add the following vm argument
   Djava.library.path=/PATHTOPROCESSING/Resources/Java/libraries/opengl/library