I'm just curious: Did Yazdipur try to communicate with the Omega developers and offer patches etc?
I do not think so, It seems that he has got no interest in the Unicode world and he is a big fan of Knuth's TeX engine only and does not want to write codes for PDFTeX, XeTeX and LuaTeX.
Another question: TeX-e-Parsi was originally closed source, I think: What is the status of the source code?
Yes, it was closed but it has been open source since a few years back.
Have you tested the bidi in luatex and compared it with that of TeX-e-Parsi? It is already much better than etex's.
Yes, I did and I still think TeX-e-Parsi's bidirectional algorithm is more powerful than LuaTeX's.
According to Behdad Esfahbod and Roozbeh Pournader,
http://www.tug.org/TUGboat/Articles/tb23-1/farsitex.pdf
TeX-e-Parsi has not been developed since 1996. I know that there has been development of Omega since then, including a new bidi model -- with new primitives -- that replaced the one in pre-1996 Omega. Looking at the primitive list you provided, I don't think TeX-e-Parsi builds on the later, improved Omega model.
The Behdad's paper was written in 2002 and in that time TeX-e-Parsi was a commercial software and so I think Behdad would have the chance to look at the source code and he just said something which was not really true. If you look at the biginning of tex.ch, in the version section, we have "% Version 3.019 reorganizing \pTeX changes (1384/12/26)". 1384 is the year of latest development, if you add 621 to 1384 (1384 is the Iranian year), you will get 2005. In fact it is the end of 205 and we can say 2006. So as you can see TeX-e-Parsi's latest development happened recently. As I said Yazdipour has faith only in Donald Knuth and his work and no interest in other TeX engines, that is what I have heard. Donald Knuth himself congratulated him for writing the TeX-e-Parsi's engine.
1. Make an exhaustive test suite that compares bidi behavior in luatex with that of TeX-e-Parsi. You don't need to use any arabic-script, just latin modern samples;
I absolutely agree. But Let's have a test file. I write that test file with TeX-e-Parsi and you write the test file with LuaTeX and then we compare the results. If you can send a sample/test file so then I can typeset in with TeX-e-Parsi.
2. Identify the diffferences between the two and determine which -- if either -- has the saner behavior for each case;
Agree. It might turns out that TeX-e-Parsi is powerful in some areas and LuaTeX in other areas. So we just can look at the powerful areas of bidirectional typesetting.
3. Make specific feature/debugging requests and -- if possible -- point to areas where TeX-e-Parsi code may be useful in implementing the features you want.
No Problem.
As I mentioned above, I think the last Omega primitives are newer than TeX-e-Parsi's. But a related issue: Are those primitives based on the unicode bidi algorithm? There is also an ongoing implementation of the algorithm in the MKIV inteface to luatex. Again, the best thing may be to identify missing features and bugs, then the developers can identify the best approach to implementing/fixing things. That may or may not involve using TeX-e-Parsi code.
Agree. _________________________________________________________________ Time for change? Find your ideal job with SEEK. http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fninemsn%2Eseek%2Ecom%2Eau%2F%3Ftracking%3Dsk%3Atl%3Ask%3Anine%3A0%3Ahottag%3Achange&_t=757263783&_r=SEEK_tagline&_m=EXT