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Commit 6702e8ad authored by Luigi Scarso's avatar Luigi Scarso
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always use old school tex logic (also for opentype) wrt italics 

with exception for large operators in opentyep fonts (no mixed font
usage); all related control modes removed (H.Hagen)
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manual/luatex-math.tex
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......@@ -773,120 +773,120 @@ hasn't been the case since the start of the project. Changing it could break
hacks that users came up with but when you set \lpr {matheqdirmode} to a positive
value direction will be taken into account.
\subsection {Nolimit correction}
\topicindex {math+limits}
There are two extra math parameters \lpr {Umathnolimitsupfactor} and \lpr
{Umathnolimitsubfactor} that were added to provide some control over how limits
are spaced (for example the position of super and subscripts after integral
operators). They relate to an extra parameter \lpr {mathnolimitsmode}. The half
corrections are what happens when scripts are placed above and below. The
problem with italic corrections is that officially that correction italic is used
for above|/|below placement while advanced kerns are used for placement at the
right end. The question is: how often is this implemented, and if so, do the
kerns assume correction too. Anyway, with this parameter one can control it.
\starttabulate[|l|ck1|ck1|ck1|ck1|ck1|ck1|]
\NC % probably not ok, we need a raw int here
\NC \mathnolimitsmode0 $\displaystyle\mathop{\normalint}\nolimits^0_1$
\NC \mathnolimitsmode1 $\displaystyle\mathop{\normalint}\nolimits^0_1$
\NC \mathnolimitsmode2 $\displaystyle\mathop{\normalint}\nolimits^0_1$
\NC \mathnolimitsmode3 $\displaystyle\mathop{\normalint}\nolimits^0_1$
\NC \mathnolimitsmode4 $\displaystyle\mathop{\normalint}\nolimits^0_1$
\NC \mathnolimitsmode8000 $\displaystyle\mathop{\normalint}\nolimits^0_1$
\NC \NR
\TB
\BC mode
\NC \tttf 0
\NC \tttf 1
\NC \tttf 2
\NC \tttf 3
\NC \tttf 4
\NC \tttf 8000
\NC \NR
\BC superscript
\NC 0
\NC font
\NC 0
\NC 0
\NC +ic/2
\NC 0
\NC \NR
\BC subscript
\NC -ic
\NC font
\NC 0
\NC -ic/2
\NC -ic/2
\NC 8000ic/1000
\NC \NR
\stoptabulate
When the mode is set to one, the math parameters are used. This way a macro
package writer can decide what looks best. Given the current state of fonts in
\CONTEXT\ we currently use mode 1 with factor 0 for the superscript and 750 for
the subscripts. Positive values are used for both parameters but the subscript
shifts to the left. A \lpr {mathnolimitsmode} larger that 15 is considered to
be a factor for the subscript correction. This feature can be handy when
experimenting.
\subsection {Math italic mess}
\topicindex {math+italics}
The \lpr {mathitalicsmode} parameter was introduced to deal with the difference
in applying italic correction in traditional and \OPENTYPE\ math fonts. There are
\OPENTYPE\ fonts out there that have italic correction and assume them to be
applied like traditional \TEX\ fonts. This parameter takes several values:
When set to zero, you get what was decided when the two code paths (traditional
and \OPENTYPE) were introduced.
Values larger than zero will add the italic correction between simple noads (it
checks some classes so you might pay attention to for instance punctuation
classes assigned).
When set to zero or one, italics are independent, so we separate width from
italic, while values larger than one combine both in the width but later
selectively has to get rid of it (depending on code path).
A value larger than two will backtrack italics for large operators, because there
italic correction is used for anchoring scripts (limits and no limits). In fact,
\OPENTYPE\ uses italics either between characters or for this purpose but as
mentioned fonts are sort of messy here.
We tested our version of plain \TEX\ and recommend to use the value of three to
get the best average results. More about this italic correction dilemma in
rendering math can be found in articles (in for instance \TUGBOAT) and various
documents in the \CONTEXT\ distribution, especially those that discuss the
upgraded math engine in \LUAMETATEX.
% The \lpr {mathitalicsmode} parameter can be set to~1 to force italic correction
% before noads that represent some more complex structure (read: everything that is
% not an ord, bin, rel, open, close, punct or inner). A value of~2 will enforce the
% old school font code path for all italics. We show a Cambria example.
% \subsection {Nolimit correction}
%
% \topicindex {math+limits}
%
% \starttexdefinition Whatever #1
% \NC \type{\mathitalicsmode = #1}
% \NC \mathitalicsmode#1\ruledhbox{$\left|T^1\right|$}
% \NC \mathitalicsmode#1\ruledhbox{$\left|T\right|$}
% \NC \mathitalicsmode#1\ruledhbox{$T+1$}
% \NC \mathitalicsmode#1\ruledhbox{$T{1\over2}$}
% \NC \mathitalicsmode#1\ruledhbox{$T\sqrt{1}$}
% There are two extra math parameters \lpr {Umathnolimitsupfactor} and \lpr
% {Umathnolimitsubfactor} that were added to provide some control over how limits
% are spaced (for example the position of super and subscripts after integral
% operators). They relate to an extra parameter \lpr {mathnolimitsmode}. The half
% corrections are what happens when scripts are placed above and below. The
% problem with italic corrections is that officially that correction italic is used
% for above|/|below placement while advanced kerns are used for placement at the
% right end. The question is: how often is this implemented, and if so, do the
% kerns assume correction too. Anyway, with this parameter one can control it.
% \starttabulate[|l|ck1|ck1|ck1|ck1|ck1|ck1|]
% \NC % probably not ok, we need a raw int here
% \NC \mathnolimitsmode0 $\displaystyle\mathop{\normalint}\nolimits^0_1$
% \NC \mathnolimitsmode1 $\displaystyle\mathop{\normalint}\nolimits^0_1$
% \NC \mathnolimitsmode2 $\displaystyle\mathop{\normalint}\nolimits^0_1$
% \NC \mathnolimitsmode3 $\displaystyle\mathop{\normalint}\nolimits^0_1$
% \NC \mathnolimitsmode4 $\displaystyle\mathop{\normalint}\nolimits^0_1$
% \NC \mathnolimitsmode8000 $\displaystyle\mathop{\normalint}\nolimits^0_1$
% \NC \NR
% \TB
% \BC mode
% \NC \tttf 0
% \NC \tttf 1
% \NC \tttf 2
% \NC \tttf 3
% \NC \tttf 4
% \NC \tttf 8000
% \NC \NR
% \BC superscript
% \NC 0
% \NC font
% \NC 0
% \NC 0
% \NC +ic/2
% \NC 0
% \NC \NR
% \stoptexdefinition
% \BC subscript
% \NC -ic
% \NC font
% \NC 0
% \NC -ic/2
% \NC -ic/2
% \NC 8000ic/1000
% \NC \NR
% \stoptabulate
%
% When the mode is set to one, the math parameters are used. This way a macro
% package writer can decide what looks best. Given the current state of fonts in
% \CONTEXT\ we currently use mode 1 with factor 0 for the superscript and 750 for
% the subscripts. Positive values are used for both parameters but the subscript
% shifts to the left. A \lpr {mathnolimitsmode} larger that 15 is considered to
% be a factor for the subscript correction. This feature can be handy when
% experimenting.
% \subsection {Math italic mess}
%
% \topicindex {math+italics}
%
% The \lpr {mathitalicsmode} parameter was introduced to deal with the difference
% in applying italic correction in traditional and \OPENTYPE\ math fonts. There are
% \OPENTYPE\ fonts out there that have italic correction and assume them to be
% applied like traditional \TEX\ fonts. This parameter takes several values:
%
% When set to zero, you get what was decided when the two code paths (traditional
% and \OPENTYPE) were introduced.
%
% Values larger than zero will add the italic correction between simple noads (it
% checks some classes so you might pay attention to for instance punctuation
% classes assigned).
%
% When set to zero or one, italics are independent, so we separate width from
% italic, while values larger than one combine both in the width but later
% selectively has to get rid of it (depending on code path).
%
% A value larger than two will backtrack italics for large operators, because there
% italic correction is used for anchoring scripts (limits and no limits). In fact,
% \OPENTYPE\ uses italics either between characters or for this purpose but as
% mentioned fonts are sort of messy here.
%
% \start
% \switchtobodyfont[cambria]
% \starttabulate[|c|c|c|c|c|c|]
% \Whatever{0}%
% \Whatever{1}%
% \stoptabulate
% \stop
% We tested our version of plain \TEX\ and recommend to use the value of three to
% get the best average results. More about this italic correction dilemma in
% rendering math can be found in articles (in for instance \TUGBOAT) and various
% documents in the \CONTEXT\ distribution, especially those that discuss the
% upgraded math engine in \LUAMETATEX.
%
% This kind of parameters relate to the fact that italic correction in \OPENTYPE\
% math is bound to fuzzy rules. So, control is the solution.
% % The \lpr {mathitalicsmode} parameter can be set to~1 to force italic correction
% % before noads that represent some more complex structure (read: everything that is
% % not an ord, bin, rel, open, close, punct or inner). A value of~2 will enforce the
% % old school font code path for all italics. We show a Cambria example.
% %
% % \starttexdefinition Whatever #1
% % \NC \type{\mathitalicsmode = #1}
% % \NC \mathitalicsmode#1\ruledhbox{$\left|T^1\right|$}
% % \NC \mathitalicsmode#1\ruledhbox{$\left|T\right|$}
% % \NC \mathitalicsmode#1\ruledhbox{$T+1$}
% % \NC \mathitalicsmode#1\ruledhbox{$T{1\over2}$}
% % \NC \mathitalicsmode#1\ruledhbox{$T\sqrt{1}$}
% % \NC \NR
% % \stoptexdefinition
% %
% % \start
% % \switchtobodyfont[cambria]
% % \starttabulate[|c|c|c|c|c|c|]
% % \Whatever{0}%
% % \Whatever{1}%
% % \stoptabulate
% % \stop
% %
% % This kind of parameters relate to the fact that italic correction in \OPENTYPE\
% % math is bound to fuzzy rules. So, control is the solution.
\subsection {Script and kerning}
......
manual/luatex.pdf
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− 0
View file @ 6702e8ad
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source/texk/web2c/luatexdir/ChangeLog
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View file @ 6702e8ad
2025-03-16 Luigi Scarso <luigi.scarso@gmail.com>
* always use old school tex logic (also for opentype) wrt italics
with exception for large operators in opentyep fonts (no mixed font
usage); all related control modes removed (H.Hagen)
2025-03-15 Luigi Scarso <luigi.scarso@gmail.com>
* : italicsmode fix for eight bit fonts (H.Hagen)
* italicsmode fix for eight bit fonts (H.Hagen)
2025-03-13 Luigi Scarso <luigi.scarso@gmail.com>
* extra italicsmode (large operator italic spacing) (H.Hagen)
2025-02-28 Akira Kakuto <kakuto@jcom.zaq.ne.jp>
* luatex.c: Remove problematic lines for windows
......
source/texk/web2c/luatexdir/luatex_svnversion.h
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#ifndef luatex_svn_revision_h
#define luatex_svn_revision_h
#define luatex_svn_revision 7672
#define luatex_svn_revision 7673
#endif
source/texk/web2c/luatexdir/tex/mlist.c
+ 66
− 284
View file @ 6702e8ad
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