Performance issues and ideas

It seems that performance issues are caused by too many nodes attached to the rootNode manager (the one that handles all the geometry in the scene). I have asked the question on the forum (here) and there were some solutions gives, as well as some ideas made up in my mind.

Well, one way is to somehow lower the amount of custom nodes while saving the same amount of triangles in the scene. This can be done if I make a constant mesh from many nodes and only then add it to the rootNode manager. So I have to write a procedure that reads all my quad tree, finds all nodes that have to be rendered (i.e. are leafs) that are on the same level in my quad tree, and makes a constant mesh (TriMesh to be exact by java terminology) and then pass it to the scene manager. And that for all tree levels.

Another thought that I had was related with splitting. In my previous posts I mentioned that according to my splitting procedure the quad splits on 4 smaller. In future the idea was to split the quad if camera is close o it so to add more detail. But splitting only one segment each time won't add much of a nice picture, imho. I think I need to "split" quads for some segment bigger than one parent quad. That way adding more detail won't be so.. mmm... so rude, maybe. Somehow like this.

So, I believe I will focus on this.