diagrams/diagrams-cairo — pull request #36 by byorgey (2013-11-05 19:48:52+00:00)
Title: Backend tree conversion

Port of `diagrams-cairo` to use the new `RTree` interface. All tests now pass. I considered cleaning this up by squashing into just a few commits, but all the bugs I encountered are quite instructive (as, I hope, are the detailed commit messages).