Tuesday, March 17, 2009

GEF3D goes X3D

Due to problems of getting LWJGL IP approved, we were wondering how to address this problem. We didn't want to fall into the same trap again, so we thought about how to reduce GEF3D's dependencies from a specific rendering library. The problem was not trivial at all, so I decided to give it to a student, Matthias Thiele. He should analyze GEF3D and its dependencies to the currently used rendering library LWJGL in the context of a bachelor thesis. The idea was to refactor GEF3D (i.e. Draw3D) in order to minimize dependencies and to create a generic renderer interface. Making renderers plugable leads to the idea of using renderers not only for drawing on the screen, but for exporting or printing, too. So besides the refactoring, a new renderer should be implemented... GEF provides several export formats, for example SVG for exchanging diagrams in a vector based file format. What SVG is for 2D diagrams, X3D is for 3D ones. So, besides the existing LWJGL-based renderer, Matthias implemented an X3D renderer. And Matthias did a great job! Based on his analysis of the GEF3D and Draw3D code, using cool tools like InferType (see intoJ project), we (that is Kristian, Matthias and myself) created a new design for Draw3D's rendering parts and we introduced an extension point to make renderers plugable! Matthias did most of the refactoring, actually before GEF3D was submitted to Eclipse. On the way we had to fix some bugs related to this (e.g. a 3D position problem or a dispose problem), but eventually it seems to work fine. Matthias wrote the X3D renderer, and he has contributed the code today. It is not available in the SVN yet, since we have to get it IP approved, first. Here you can see the result of the X3D export: The original GEF3D diagram is shown at the bottom left. The large diagram is the very same image, exported as X3D and viewed with the instantplayer. The small image on the top left shows the very same X3D file, this time rendered with the Octaga Player. The current version of the X3D exporter is only a beginning. We certainly have to improve the quality of the diagrams, but it shows what is possible. Maybe other programmers write other cool renderers for GEF3D in the future ;-)

1 comment:

Holger Seelig said...

The exported files works great with Titania X3D Browser, thanks.