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<p>Hi</p>
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<p>XeTeX uses TeX--XeT algorithm and has some serious problems in typesetting right to left text. About few years ago, I wrote to <span>Peter Breitenlohner and we discussed together what needs to be fixed. Peter promised that he would fix the issues but
unfortunately he passed away. I believe he at least fixed one of the bugs I reported to him. </span></p>
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<p><span>Bidirectional typesetting is a very fundamental area which unfortunately has been ignored so far. I can think of two ways to improve the situation:</span></p>
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<p><span>A) Drop the TeX--XeT model entirely and switch to LuaTeX (Omega) bidi model</span></p>
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<p><span>Unfortunately Omega's bidi model has its own set of bugs so even if XeTeX goes this route, we need to fix quite some issues in its bidi model.</span></p>
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<p>B) Switch to the original TeX-XeT model by Knuth</p>
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<p>I would prefer this approach (considering my over 10 years of experience with both TeX--XeT and Omega bidi model) as it is more stable than Omega's bidi model. If I recall correctly, Khaled Hosny did this in 2013 and when I was testing most of the problems
were fixed. The only issue was that the original TeX-XeT model adds \beginL ... \endL and that would cause some problem in math typesetting (sorry, I can not remember what exactly it was about but I remember it was reported by David Carlisle). For this problem,
one can look at TeX--XeT and see how display math are done there and we could apply the same approach to TeX-XeT model.</p>
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<p>Once this is done, we can also look at ParsiTeX source[1] which is also based on TeX--XeT and add few primitives which are essential for bidi such as \Rhalign (making RTL tables).</p>
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<p>Conclusion: I am not going to sit and watch like before! if XeTeX bidi model is not improved until TeXLive 2017, I am going to fork XeTeX, rename it to something else and make the changes I need. This is indeed last time I try to talk about it with the XeTeX
team. I have done it numerous times and each time the bidi problems were ignored.</p>
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<p>[1] <a href="http://ctan.org/pkg/parsitex" class="OWAAutoLink" id="LPlnk265921" previewremoved="true">http://ctan.org/pkg/parsitex</a></p>
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<a id="LPUrlAnchor_14795686225450.8650838690846643" href="http://ctan.org/pkg/parsitex" target="_blank" style="text-decoration: none;">CTAN: Package parsitex</a></div>
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ctan.org</div>
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Suggestions. Maybe you are interested in the following packages as well. nts: New Typesetting System; vtex-free: T e X system and PDF support ...</div>
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