Today I am worked on migrating FREEdraft from my homegrown geometry objects and storage model to Open Cascade. - (the very cool smart pointers.) My plan is to use geometry and storage model of cascade, but not the visualization - as I think what I have already is nice.
The occ library maps suprisingly well to what I have already built in FREEdraft.
I still have major rewriting.. ahead before I can get it working again though.
And then some.