From 6afde2e3016d61342977c55ac7f4a71e38adcb76 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jean-Fran=C3=A7ois=20B?=
 <2589111+jfbu@users.noreply.github.com>
Date: Thu, 30 Jun 2022 19:45:41 +0200
Subject: [PATCH] LaTeX: refactor sphinxShadowBox to allow colors for frame and
 shadow

---
 doc/latex.rst                             | 16 +++++++++-
 sphinx/texinputs/sphinx.sty               |  5 ++-
 sphinx/texinputs/sphinxlatexshadowbox.sty | 39 +++++++++++++++++------
 3 files changed, 48 insertions(+), 12 deletions(-)

diff --git a/doc/latex.rst b/doc/latex.rst
index 294de559907..0140d0b2c9e 100644
--- a/doc/latex.rst
+++ b/doc/latex.rst
@@ -846,7 +846,7 @@ Do not use quotes to enclose values, whether numerical or strings.
     Default: ``5pt``
 
 ``shadowsize``
-    The width of the lateral "shadow" to the right.
+    The width of the lateral "shadow" to the right and bottom.
 
     Default: ``4pt``
 
@@ -855,6 +855,20 @@ Do not use quotes to enclose values, whether numerical or strings.
 
     Default: ``\fboxrule``
 
+``shadowBorderColor``
+    The color of the frame around :dudir:`topic` boxes.
+
+    Default: ``{rgb}{0,0,0}`` (black)
+
+    .. versionadded:: 5.1.0
+
+``shadowShadowColor``
+    The color of the lateral "shadow" to the right and bottom.
+
+    Default: ``{rgb}{0,0,0}`` (black)
+
+    .. versionadded:: 5.1.0
+
 |notebdcolors|
     The colour for the two horizontal rules used by Sphinx in LaTeX for styling
     a :dudir:`note` type admonition.
diff --git a/sphinx/texinputs/sphinx.sty b/sphinx/texinputs/sphinx.sty
index 930d1b64f67..b67722c1bfa 100644
--- a/sphinx/texinputs/sphinx.sty
+++ b/sphinx/texinputs/sphinx.sty
@@ -6,7 +6,7 @@
 %
 
 \NeedsTeXFormat{LaTeX2e}[1995/12/01]
-\ProvidesPackage{sphinx}[2021/01/27 v4.0.0 LaTeX package (Sphinx markup)]
+\ProvidesPackage{sphinx}[2022/06/30 v5.1.0 LaTeX package (Sphinx markup)]
 
 % provides \ltx@ifundefined
 % (many packages load ltxcmds: graphicx does for pdftex and lualatex but
@@ -154,6 +154,9 @@
 }%
 % Default color chosen to be as in minted.sty LaTeX package!
 \sphinxDeclareSphinxColorOption{VerbatimHighlightColor}{{rgb}{0.878,1,1}}
+% topic and contents boxes
+\sphinxDeclareSphinxColorOption{shadowBorderColor}{{rgb}{0,0,0}}
+\sphinxDeclareSphinxColorOption{shadowShadowColor}{{rgb}{0,0,0}}
 % admonition boxes, "light" style
 \sphinxDeclareSphinxColorOption{noteBorderColor}{{rgb}{0,0,0}}
 \sphinxDeclareSphinxColorOption{hintBorderColor}{{rgb}{0,0,0}}
diff --git a/sphinx/texinputs/sphinxlatexshadowbox.sty b/sphinx/texinputs/sphinxlatexshadowbox.sty
index 8d6c78666cf..420fee2f2bd 100644
--- a/sphinx/texinputs/sphinxlatexshadowbox.sty
+++ b/sphinx/texinputs/sphinxlatexshadowbox.sty
@@ -1,7 +1,7 @@
 %% TOPIC AND CONTENTS BOXES
 %
 % change this info string if making any custom modification
-\ProvidesFile{sphinxlatexshadowbox.sty}[2021/01/27 sphinxShadowBox]
+\ProvidesFile{sphinxlatexshadowbox.sty}[2022/06/30 sphinxShadowBox]
 
 % Provides support for this output mark-up from Sphinx latex writer:
 %
@@ -17,30 +17,48 @@
 % Requires:
 \RequirePackage{framed}
 
-% Again based on use of "framed.sty", this allows breakable framed boxes.
+% Let's draw the contents first, then the frame and the shadow last,
+% to avoid problems with some pdf viewers.
 \long\def\spx@ShadowFBox#1{%
   \leavevmode\begingroup
-  % first we frame the box #1
+  % first we prepare a box with the contents in an invisible frame
   \setbox\@tempboxa
-   \hbox{\vrule\@width\sphinxshadowrule
-         \vbox{\hrule\@height\sphinxshadowrule
+   \hbox{\kern\sphinxshadowrule
+         \vbox{\kern\sphinxshadowrule
                \kern\sphinxshadowsep
                \hbox{\kern\sphinxshadowsep #1\kern\sphinxshadowsep}%
                \kern\sphinxshadowsep
+               \kern\sphinxshadowrule}%
+         \kern\sphinxshadowrule}%
+  % now we unbox the previous one, drawing contents first, then
+  % we frame it with a color
+  \setbox\@tempboxa
+   \hbox{\unhcopy\@tempboxa
+         \kern-\wd\@tempboxa
+         {\color{sphinxshadowBorderColor}%
+         \vrule\@width\sphinxshadowrule
+         \vbox{\hrule\@height\sphinxshadowrule
+               \kern\dimexpr\ht\@tempboxa-\sphinxshadowrule\relax
+               \hbox{\kern\dimexpr\wd\@tempboxa-2\sphinxshadowrule\relax}%
+               \kern\dimexpr\dp\@tempboxa-\sphinxshadowrule\relax
                \hrule\@height\sphinxshadowrule}%
          \vrule\@width\sphinxshadowrule}%
+         }%
   % Now we add the shadow, like \shadowbox from fancybox.sty would do
-  \dimen@\dimexpr.5\sphinxshadowrule+\sphinxshadowsize\relax
+  % Formerly, shadow was drawn partly on top of frame, but this was
+  % before both frame and shadow acquired colors.
   \hbox{\vbox{\offinterlineskip
-              \hbox{\copy\@tempboxa\kern-.5\sphinxshadowrule
+              \hbox{\copy\@tempboxa
                     % add shadow on right side
                     \lower\sphinxshadowsize
-                          \hbox{\vrule\@height\ht\@tempboxa \@width\dimen@}%
+                          \hbox{{\color{sphinxshadowShadowColor}%
+                                 \vrule\@height\ht\@tempboxa \@width\sphinxshadowsize}}%
                     }%
-              \kern-\dimen@ % shift back vertically to bottom of frame
+              \kern-\sphinxshadowsize % shift back vertically to bottom of frame
               % and add shadow at bottom
               \moveright\sphinxshadowsize
-                    \vbox{\hrule\@width\wd\@tempboxa \@height\dimen@}%
+                    \vbox{{\color{sphinxshadowShadowColor}%
+                           \hrule\@width\wd\@tempboxa \@height\sphinxshadowsize}}%
               }%
         % move left by the size of right shadow so shadow adds no width
         \kern-\sphinxshadowsize
@@ -48,6 +66,7 @@
   \endgroup
 }
 
+% Again based on use of "framed.sty", this allows breakable framed boxes.
 % use framed.sty to allow page breaks in frame+shadow
 % works well inside Lists and Quote-like environments
 % produced by ``topic'' directive (or local contents)