16 Change LogTop14 The Ipe file format15 If you have used Ipe 5 before...

15 If you have used Ipe 5 before...

...you may be shocked about some of the new developments in Ipe 6. In particular, the clever Ipe file format that gave Ipe its name has disappeared. (You do remember, of course, that Ipe used to stand for "Integrated Picture Environment", because Ipe files were at the same time legal Latex source code and Postscript files.)

Ipe 6 simply writes Postscript or PDF files. It still maintains text objects as Latex source, and you edit text objects by editing Latex source, but before creating an Ipe file, Ipe runs Pdflatex and stores the resulting PDF representation in the file. This is a much better solution, as Ipe figures now require no special handling. You no longer have to add page-long explanations when you send Ipe files to a co-author or publisher. The new approach was made possible by two important developments that have happened since 1993, when I first wrote Ipe. First, all relevant Latex fonts are now available as scalable Type1 fonts, and so it is possible to embed Latex text and formulas in figures that may still need to be scaled later. Second, Hàn Thê Thàn's pdfTeX, a version of TeX that produces PDF instead of DVI output, makes it possible for Ipe to extract the processed text objects from a Latex run and to include them in its own output.

The Ghostscript window is also no longer necessary, as Ipe can now render text objects the way they will look on paper.

Perhaps you are worried now that you cannot continue to use your megabytes worth of existing Ipe figures with Ipe 6. Fear not. Ipe 6 comes with a tool "ipe5toxml" that converts figures created with Ipe 5 and earlier to Ipe 6's XML format. In fact, you can just select an old Ipe file from the Ipe user interface, and Ipe will run the tool for you automatically. (There was no question that Ipe 6 would have to be able to communicate in XML, of course.)

Other than the file format, there aren't really that many changes to Ipe's functionality. I've added style sheets and layers, because René van Oostrum says that no self-respecting drawing program can do without. I've added page presentation sequences, which allow you to incrementally build up a page in a PDF presentation, because Christian Knauer wants to make PowerPoint-like presentations in Ipe. And obviously it's now possible to use Korean, Chinese, and Japanese in figures.

I've also revised the interface to ipelets (which used to be called "Iums" in the good old times when people still though that "applets" were small apples)--it is now based on dynamically loaded libraries (a technology that was still somewhat poorly understood ten years ago, at least by me). Ipelets are now much more powerful than they used to be, but buggy ipelets can also crash Ipe much more easily than in the past. Well, you can always do the real work in a separate program, I guess.

Finally, Ipe 6 has been rewritten from scratch in clean, beautiful, object-oriented C++. Quite unlike the previous version. Oh, and there's a Windows version of Ipe now. Who would have thought that ten years ago!


16 Change LogTop14 The Ipe file format15 If you have used Ipe 5 before...