[latexrefman-commits] [SCM] latexrefman updated: r844 - trunk

[karl at gnu.org.ua]

Author: karl
Date: 2020-11-26 19:50:57 +0200 (Thu, 26 Nov 2020)
New Revision: 844

Modified:
   trunk/ChangeLog
   trunk/latex2e.texi
Log:
italic correction not auto-inserted with declarations like \em

Modified: trunk/ChangeLog
===================================================================
--- trunk/ChangeLog	2020-11-26 17:24:21 UTC (rev 843)
+++ trunk/ChangeLog	2020-11-26 17:50:57 UTC (rev 844)
@@ -1,5 +1,8 @@
 2020-11-26  Karl Berry  <karl at freefriends.org>
 
+	* latex2e.texi (\/): commands like \emph and \textit auto-insert
+	italic corrections, declarations like \em and \itshape don't.
+
 	* latex2e.texi (Spacing in math mode),
 	(\thinspace & \negthinspace): all math spacing commands
 	can be used in text as of 2020-10-01 release, or with amsmath.

Modified: trunk/latex2e.texi
===================================================================
--- trunk/latex2e.texi	2020-11-26 17:24:21 UTC (rev 843)
+++ trunk/latex2e.texi	2020-11-26 17:50:57 UTC (rev 844)
@@ -2057,7 +2057,7 @@
 One advantage of these commands is that they automatically insert italic
 corrections if needed (@pxref{\/}).  Specifically, they insert the
 italic correction unless the following character is in the list
- at code{\nocorrlist}, which by default consists of a period and a comma.
+ at code{\nocorrlist}, which by default consists of period and comma.
 To suppress the automatic insertion of italic correction, use
 @code{\nocorr} at the start or end of the command argument, such as
 @code{\textit@{\nocorr text@}} or @code{\textsc@{text \nocorr@}}.
@@ -2131,8 +2131,8 @@
 
 (The unconditional commands below are an older version of font
 switching. The earlier commands are an improvement in most
-circumstances. But sometimes an unconditional font switch is precisely
-what you want.)
+circumstances. But sometimes an unconditional font switch is what is
+needed.)
 
 @ftable @code
 @item \bf
@@ -14771,10 +14771,11 @@
 @end example
 
 Insert an @dfn{italic correction}, a small space defined by the font
-designer for each character, to avoid the character colliding with
-whatever follows. When you use @code{\/}, @LaTeX{} takes the correction
-from the font metric file, scales it by any scaling that has been
-applied to the font, and then inserts that much horizontal space.
+designer for each character (possibly zero), to avoid the character
+colliding with whatever follows. When you use @code{\/}, @LaTeX{}
+takes the correction from the font metric file, scales it by any
+scaling that has been applied to the font, and then inserts that much
+horizontal space.
 
 Here, were it not for the @code{\/}, the @var{before-character}
 italic at tie{}f would hit the @var{after-character} roman at tie{}H
@@ -14784,24 +14785,36 @@
 @end example
 
 @noindent 
-because the italic letter leans far to the right.
+because the italic letter f leans far to the right.
 
 If @var{after-character} is a period or comma then don't insert an
-italic correction since those punctuation symbols have a very small
-height.  However, with semicolons or colons as well as with normal
-letters, the italic correction can help.
+italic correction since those punctuation symbols are so low to the
+baseline already.  However, with semicolons or colons, as well as with
+normal letters, the italic correction can help. It is typically used
+between a switch from italic or slanted fonts to an upright font.
 
-When you use commands such as @code{\textit} or @code{\itshape} to
-change fonts, @LaTeX{} will automatically insert any needed italic
-correction (@pxref{Font styles}).
+When you use commands such as @code{\emph} and @code{\textit} and
+ at code{\textsl} to change fonts, @LaTeX{} automatically inserts the
+italic correction when needed (@pxref{Font styles}).  However,
+declarations such as @code{\em} and @code{\itshape} and
+ at code{\slshape} do not automatically insert italic corrections.
 
-Roman characters can also have an italic correction.  An example is in
-the name @code{pdf\/\TeX}.
+Upright characters can also have an italic correction.  An example
+where this is needed is the name @code{pdf\/\TeX}. However, most
+upright characters have a zero italic correction. Some font creators
+do not include italic correction values even for italic fonts.
 
-There is no concept of italic correction in math mode; spacing is done
-in a different way.
+ at findex \fontdimen1
+ at cindex font dimension, slant
+Technically, @LaTeX{} uses another font-specific value, the so-called
+slant parameter (namely @code{\fontdimen1}), to determine whether to
+possibly insert an italic correction, rather than tying the action to
+particular font commands.
 
+There is no concept of italic correction in math mode; math spacing is
+done in a different way.
 
+
 @node \hrulefill & \dotfill
 @section @code{\hrulefill} & @code{\dotfill}