Sorry for lazy responses on this thread. In article <[EMAIL PROTECTED]>, Richard Stallman <[EMAIL PROTECTED]> writes: > Handa-san should give the definitive answer, but I think it was > always, as long as Emacs was told that the buffer _could_ contain > right-to-left text. This is because Emacs doesn't know whether there > actually is right-to-left text in the buffer, and cannot do so easily > without getting a significant performance hit (what would we do? > search the buffer for certain ranges of characters after each change > to buffer's text?).
> That is acceptable, in my opinion, because it means most users > won't lose anything. > However, it doesn't seem right to me to have an Emacs that cannot > scroll fast enough just because I've set such a flag, assuming that > Gerd's intuition is correct. IMHO, of course. As to optimization, what I disabled are, as far as I remeber: o direct_output_xxx o partial update of a line. A line is always updated fully. The other optimizatios should be still effective even if the buffer local variable `enable-bidi-display' or `orientation-reversed' are non-nil. So, for instance, just scrolling should not be delayed. One strong objection point I remember is about caching reordered glyphs in (struct it). > It is a major, but supporting your language with slower scrolling is > better than failing to support your language at all. > As Handa-san says he will try to use what I did, I think this is not > an issue anymore. If what I wrote has any value, I'm sure it will be > merged with Emacs. > That would be very good. Handa-san, can you tell us more about what > you plan to do with this code, and how much work you think it will be? In brief, what I did in emacs-bidi are: (1) change xdisp.c to call get_next_display_element_visually and set_iterator_to_next_visually instead of get_next_display_element and set_iterator_to_next. (2) make a new file bidi.c that implements get_next_display_element_visually and set_iterator_to_next_visually. (3) make a new file bidi.el that implements simple bidi-reordering function that is called from get_next_display_element_visually to create a cache in (struct it). (4) change xterm.c to display glyphs flushing to right when orientation-reversed is non-nil. My current plan is to replace (2) and (3) with Eli's code. --- Ken'ichi HANDA [EMAIL PROTECTED] _______________________________________________ Developer mailing list [EMAIL PROTECTED] http://lists.arabeyes.org/mailman/listinfo/developer
