From c1c86bee7ff3ae83ee3cd6612ae955f01e0314bd Mon Sep 17 00:00:00 2001
From: Ross Churchley <ross@rosschurchley.com>
Date: Thu, 9 Jul 2015 18:32:09 -0700
Subject: [PATCH] Fix #111

---
 beamerinnerthememetropolis.dtx | 22 +++++++++++++++++++---
 beamerouterthememetropolis.dtx | 20 --------------------
 beamerthemem.dtx               |  5 +----
 3 files changed, 20 insertions(+), 27 deletions(-)

diff --git a/beamerinnerthememetropolis.dtx b/beamerinnerthememetropolis.dtx
index e473686..1c866c4 100644
--- a/beamerinnerthememetropolis.dtx
+++ b/beamerinnerthememetropolis.dtx
@@ -301,7 +301,6 @@
   }
 }
 \defbeamertemplate{section page}{progressbar}{
-  \vspace{2em}
   \centering
   \begin{minipage}{22em}
     \usebeamercolor[fg]{section title}
@@ -474,13 +473,30 @@
 %
 %
 %
-% \subsubsection{General text settings}
+% \subsubsection{Text and spacing settings}
+%
 %    \begin{macrocode}
-\mode<all>
 \setlength{\parskip}{0.5em}
 \linespread{1.15}
 %    \end{macrocode}
 %
+% By default, Beamer frames offer the |c| option to \textit{almost} vertically
+% center the text, but the placement is a little too high. To fix this, we
+% redefine the |c| option to equalize |\beamer@frametopskip| and
+% |\beamer@framebottomskip|. This solution was suggested by Enrico Gregorio in
+% an answer to \href{http://tex.stackexchange.com/questions/247826/}{this
+% Stack Exchange question}.
+%
+%    \begin{macrocode}
+\define@key{beamerframe}{c}[true]{% centered
+  \beamer@frametopskip=0pt plus 1fill\relax%
+  \beamer@framebottomskip=0pt plus 1fill\relax%
+  \beamer@frametopskipautobreak=0pt plus .4\paperheight\relax%
+  \beamer@framebottomskipautobreak=0pt plus .6\paperheight\relax%
+  \def\beamer@initfirstlineunskip{}%
+}
+%    \end{macrocode}
+%
 % Process package options
 %
 %    \begin{macrocode}
diff --git a/beamerouterthememetropolis.dtx b/beamerouterthememetropolis.dtx
index 8ab52f4..63a29dd 100644
--- a/beamerouterthememetropolis.dtx
+++ b/beamerouterthememetropolis.dtx
@@ -86,17 +86,6 @@
 %    \end{macrocode}
 % \end{macro}
 %
-% \begin{macro}{frametitleoffset}
-% This option controls the frame title offset.
-%    \begin{macrocode}
-\pgfkeys{
-  /metropolis/outer/.cd,
-    frametitleoffset/.code=\setlength{\@metropolis@voffset}{#1},
-    noframetitleoffset/.code=\setlength{\@metropolis@voffset}{0em},
-}
-%    \end{macrocode}
-% \end{macro}
-%
 % \begin{macro}{\@metropolis@outer@setdefaults}
 % Set default values for outer theme options.
 %    \begin{macrocode}
@@ -105,7 +94,6 @@
     numbering=counter,
     progressbar=none,
     frametitleformat=lowercase,
-    frametitleoffset=2em,
   }
 }
 %    \end{macrocode}%
@@ -137,12 +125,6 @@
 }
 %    \end{macrocode}
 %
-% Define additional space between frame title and content. By default 2em.
-%
-%    \begin{macrocode}
-\newlength{\@metropolis@voffset}
-%    \end{macrocode}
-%
 % The only element in the footline by default is the frame number.
 %
 %    \begin{macrocode}
@@ -210,7 +192,6 @@
     ]{frametitle}
   \insertframetitle%
   \end{beamercolorbox}%
-  \vspace{\@metropolis@voffset}
 }
 \defbeamertemplate{frametitle}{progressbar}{%
   \nointerlineskip
@@ -224,7 +205,6 @@
   \insertframetitle%
   \end{beamercolorbox}%
   \usebeamertemplate*{progress bar in head/foot}
-  \vspace{\@metropolis@voffset}
 }
 %    \end{macrocode}
 % \end{macro}
diff --git a/beamerthemem.dtx b/beamerthemem.dtx
index 606de68..9e6d9c4 100644
--- a/beamerthemem.dtx
+++ b/beamerthemem.dtx
@@ -186,14 +186,11 @@
       use=palette primary,
       parent=palette primary
     }
-    \begin{frame}{#1}
+    \begin{frame}[c]{#1}
       \centering
-      \vfill
-      \vspace{1em}
       \usebeamercolor[fg]{palette primary}
       \usebeamerfont{section title}
       \@metropolis@plaintitleformat{#2}
-      \vfill
     \end{frame}
   \endgroup
 }