He did the blocks by combining some basic cubic meshes (with one, two or three faces not present) if I remember correctly.
For the wireframe box, there is a Line3D example in the wiki (or you can make a mesh for it and display it only as a wireframe, don't know which is 'best'/easier).
Kanma wrote:He did the blocks by combining some basic cubic meshes (with one, two or three faces not present) if I remember correctly.
Yes. That was to get the filleting on the edges, but it took 15 (2^4-1) different meshes for my situation with 4 possible neighbours. In 3d you'd probably have up to 6 neighbours, and that's 63 meshes although some could be rotations of others. That's a lot to make by hand, so I'd recommend sticking with one simple cube mesh (for a start at least).
For the wireframes the Line3D is good as Kanma says. You can also ake your own SimpleRenderable subclass and use Line3D for inspiration.