It should be now possible underlining or striking out any kind
of math inset containing any math construct indigestible to ulem.
While this was already possible for inline math insets, they could
have break if an aligned environment was used, for example.
This is now possible also for diplay math. Even if this can be
nonsensical and not visually perfect, at least no latex errors
should be generated if one tries to.
This should avoid performance problems related to the window update machinery.
Moreover this fixes a crash introduced by 82808fea when closing a file.
Note that GuiWorkArea::Private already had a read_only_ member, but it
was unused.
Also rename LyXVC::vcname() to LyXVC::vcstatus() since it now contains
directly the UI string to be shown.
Font changes are brought inside the \lyxdeleted macro, just before
outputting the latex code for the math inset. The inset writes a
signature before itself and this is checked by \lyxsout for recognizing
a display math. So, the font changes confuse \lyxsout, which also
swallows the first macro at the very start of \lyxdeleted. The result
is that the font changing command is not seen by latex and \sout is also
used to further strike out the formula already striked out by tikz.
This commit makes sure that the expected signature actually appears
just after the opening brace of \lyxdeleted. It also accounts for a
paragraph break occurring just before the math inset, in order to not
introduce too much vertical space, which is noticeable when using
larger font sizes.
LaTeX refuses to break a line when it is empty. But we have to start
a new line here, otherwise the whole displayed equation would be
typeset as it were inline with previous content. The solution is to
put a zero-length space just before the line break. Moreover, this
is the right thing to do, as it simulates the extra space that is
normally added in this circumstance.
Do not use REVERSE SOLIDUS OPERATOR for backwards conversion of
\\\\textbackslash in LyX and tex2lyx.
Both, \\\\ (005C REVERSE SOLIDUS = backslash) and 0x29f5 map to
\\\\textbackslash but 005c is the preferred back-transformation.
Otherwise, using \\\\ in "mathematical text" leads to literal 0x29f5 in the LyX
source which leads to "missing character" errors with non-TeX fonts.
Showing deleted display math by enabling "Show Changes in Output" was
only possible with dvi (through dvipost). Although LyX strikes out
such formulas on screen, it was impossible obtaining an output
directly using pdflatex (or other engines producing pdf) because
ulem cannot cope with display math material and gives errors.
The solution is to strike out by ourselves such deleted formulas.
I took into account several options. One of them would produce
an output similar to dvipost (which strikes out each element), but
would have required much more changes in the output routines.
Eventually, I opted for using tikz, which gives a more clean
output (as it requires to simply adding a preamble and a postamble
to the latex code of any displayed math, instead of a mark up
tailored to each particular math construct). The look of the pdf
output is similar to the way LyX strikes out the equations on screen.
Now that there is a signal to inform the controller when the buffer view has
changed, it is no longer necessary to store a perishable pointer to a buffer
view in the dialog view. (Indeed, it was only really useful for checking whether
the new buffer view pointer was different from the old one.)
TODO: other dialogs should be audited for similar hazards.
