<div dir="ltr">Sorry for repeating this again but I think it is forgotten. This is the answer to the questions that Jonathan asked about the \beginspecial and \endspecial primitives with the attached patch which shows the main changes needed for implementing these and \semihalign primitive.<br>
<br>%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br>The primitives \beginspecial and \endspecial are defined because when<br>\special's range is more than a line in a paragraph and end of it, is in the<br>middle of another line (e.g. when 1.5 lines of a paragraph is coloured), the<br>
coloured range in RTL will not be what we expect and this is because of the<br>paragraph scan towards the lines which are adjusted from left. With these<br>two primitives (\beginspecial and \endspecial) paragraph scan algorithm can<br>
colour the range of each line that was intended to be coloured and as a<br>consequent the problem will disappear.<br><br>\beginspecial has two arguments, one of the argument is about the start of<br>special and the other argument is about the end of special \endspecial does<br>
not have any arguments and its argument is the second argument of<br>\beginspecial. So in your example \beginspecial and \endspecial would be<br>used in the following way:<br><br><br>preceding text \beginspecial{color push rgb 1 0<br>
0}{color pop} red and more red \endspecial<br>following text would work like your example<br><br><br>Therefore in the lines scan algorithm, in the end of each line, the argument<br>
of \endspecial (second argument of \beginspecial) and in the beginning of<br>next line, the argument of \beginspecial (first argument) will be added.<br>%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br><br>Could you please tell me that what you think about this? I just want to see if you really can not fix it, then I have to modify TeX line breaking algorithm. But I should be very careful with modifying TeX line breaking algorithm because <i>pierre </i><i>mackay told me that </i>"This was just what he looked into in his first attempts at a bidi TeX, but DEK looked at it and decided that it broke too many other aspects of TeX. That was what inspired him to produce his own solution, which became TeX-Xet. "<br>
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