DirectFB surface source plugin question

[Marek Pikarski]

Hello,
I would like to implement a push source plugin for DirectFB surfaces.
It should have quite the same functionality as the ximagesrc plugin.

It would be good if the plugin was merged upstream, so I have some 
questions regarding the implementation:

1. Is it a good idea to implement a base class in 
gst-plugins-good/sys/directfb and put derived classes into 
gst-plugins-bad/sys/directfb ?
2. Are there any other project guidelines which I should follow?

Regards, Marek