This is not a which is better question , all what I need to know is the points of stratigic differences , like I know that both OGL and RenderWare are not ObjectOriented While D3D is , so this is a difference , But what about the other things , like data structure of the Vertices , normals , texture handling , lighting , Camera , Buffering ..... .etc
To be more specific , I'm planning to port my D3D based engin to the other 2 platforms , so I need to put some guide lines for the time required and stages of work before I start reading their
Documentaion .
Thanx .

It may be usefull for everyone if we all put the differences we know and in the end we can make a comparsion table . So please put some hands here , specially U OpenGL guys.