fix dimension arithmetic

Makefile

@@ -96,33 +96,34 @@ fig5-gentle-inflection-after_1SELECT = wm_debug where name='fig5' AND stage='cin
 fig5-gentle-inflection-after_2SELECT = wm_debug where name='fig5' AND stage='cinflections-polygon' AND gen=1
 fig5-gentle-inflection-after_2CMAP = 1
 
-inflection-1-gentle-inflection-before_SIZE = A5
+inflection-1-gentle-inflection-before_WIDTHDIV = 2
 inflection-1-gentle-inflection-before_1SELECT = wm_debug where name='inflection-1' AND stage='bbends' AND gen=1
 inflection-1-gentle-inflection-before_2SELECT = wm_debug where name='inflection-1' AND stage='bbends-polygon' AND gen=1
 inflection-1-gentle-inflection-before_2CMAP = 1
-inflection-1-gentle-inflection-after_SIZE = A5
+inflection-1-gentle-inflection-after_WIDTHDIV = 2
 inflection-1-gentle-inflection-after_1SELECT = wm_debug where name='inflection-1' AND stage='cinflections' AND gen=1
 inflection-1-gentle-inflection-after_2SELECT = wm_debug where name='inflection-1' AND stage='cinflections-polygon' AND gen=1
 inflection-1-gentle-inflection-after_2CMAP = 1
 
-fig6-selfcrossing-before_SIZE = A7
+fig6-selfcrossing-before_WIDTHDIV = 2
 fig6-selfcrossing-before_1SELECT = wm_debug where name='fig6' AND stage='bbends' AND gen=1
 fig6-selfcrossing-before_2SELECT = wm_visuals where name='fig6-baseline'
 fig6-selfcrossing-before_2LINESTYLE = dotted
 fig6-selfcrossing-before_3SELECT = wm_visuals where name='fig6-newline'
-fig6-selfcrossing-after_SIZE = A7
+fig6-selfcrossing-after_WIDTHDIV = 2
 fig6-selfcrossing-after_1SELECT = wm_debug where name='fig6' AND stage='dcrossings' AND gen=1
 
-selfcrossing-1-before_SIZE = A7
+selfcrossing-1-before_WIDTHDIV = 2
 selfcrossing-1-before_1SELECT = wm_debug where name='selfcrossing-1' AND stage='bbends' AND gen=1
 selfcrossing-1-before_2SELECT = wm_visuals where name='selfcrossing-1-baseline'
 selfcrossing-1-before_2LINESTYLE = dotted
 selfcrossing-1-before_3SELECT = wm_visuals where name='selfcrossing-1-newline'
-selfcrossing-1-after_SIZE = A7
+selfcrossing-1-after_WIDTHDIV = 2
 selfcrossing-1-after_1SELECT = wm_debug where name='selfcrossing-1' AND stage='dcrossings' AND gen=1
 selfcrossing-1-after_2SELECT = wm_debug where name='selfcrossing-1' AND stage='bbends' AND gen=1
 selfcrossing-1-after_2LINESTYLE = invisible
 
+
 .faux_test-rivers: tests-rivers.sql wm.sql .faux_db
 	./db -f $<
 	touch $@

layer2img.py

@@ -10,17 +10,20 @@ from matplotlib import rc
 CMAP = 'tab20c'
 
 BOUNDS = ('xmin', 'ymin', 'xmax', 'ymax')
-INCH = 25.4  # mm
+INCH_MM = 25.4  # mm
 BLACK, GREEN, ORANGE, PURPLE = '#000000', '#1b9e77', '#d95f02', '#7570b3'
 PSQL_CREDS = "host=127.0.0.1 dbname=osm user=osm password=osm"
 
+# see `NOTICE` in the LaTeX document; this is the width of the main text block.
+TEXTWIDTH_CM = 12.12364
+TEXTWIDTH_INCH = TEXTWIDTH_CM * 10 / INCH_MM
 
 def plt_size(string):
     if not string:
         return None
     try:
         w, h = string.split("x")
-        return float(w) / INCH, float(h) / INCH
+        return float(w) / INCH_MM, float(h) / INCH_MM
     except Exception as e:
         raise argparse.ArgumentTypeError from e
 
@@ -87,7 +90,8 @@ def main():
     if args.size:
         fig.set_size_inches(args.size)
     else:
-        fig.set_figwidth(8.27 / args.widthdiv)
+        w = TEXTWIDTH_INCH / args.widthdiv
+        fig.set_figwidth(TEXTWIDTH_INCH / args.widthdiv)
     if c := args.clip:
         ax.set_xlim(left=c[0], right=c[2])
         ax.set_ylim(bottom=c[1], top=c[3])

mj-msc.tex

@@ -81,10 +81,12 @@ Current open-source line generalization solutions have their roots in
 \section{Introduction}
 \label{sec:introduction}
 
-\begin{itemize}
-    \item Text width in pt: \prntlen{\textwidth}
-    \item Text width in cm: {\printinunitsof{cm}\prntlen{\textwidth}}
-\end{itemize}
+\iffalse
+NOTICE: this value should be copied to layer2img.py:TEXTWIDTH, so dimensions
+of inline images are reasonable.
+
+Text width in cm: {\printinunitsof{cm}\prntlen{\textwidth}}
+\fi
 
 When creating small-scale maps, often the detail of the data source is greater
 than desired for the map. This becomes especially acute for natural features
@@ -357,12 +359,12 @@ when a single vertex is moved outwards the end of the bend.
 
 \begin{figure}[h]
     \centering
-    \begin{subfigure}[b]{.49\textwidth}
+    \begin{subfigure}[b]{.45\textwidth}
         \includegraphics[width=\textwidth]{fig5-gentle-inflection-before}
         \caption{Before applying the inflection rule}
     \end{subfigure}
     \hfill
-    \begin{subfigure}[b]{.49\textwidth}
+    \begin{subfigure}[b]{.45\textwidth}
         \includegraphics[width=\textwidth]{fig5-gentle-inflection-after}
         \caption{After applying the inflection rule}
     \end{subfigure}
@@ -425,12 +427,12 @@ following the rules of the article.
 
 \begin{figure}[h]
     \centering
-    \begin{subfigure}[b]{.4\textwidth}
+    \begin{subfigure}[b]{.45\textwidth}
         \includegraphics[width=\textwidth]{fig6-selfcrossing-before}
         \caption{Bend's baseline (dotted) is crossing a neighboring bend}
     \end{subfigure}
     \hfill
-    \begin{subfigure}[b]{.4\textwidth}
+    \begin{subfigure}[b]{.45\textwidth}
         \includegraphics[width=\textwidth]{fig6-selfcrossing-after}
         \caption{Self-crossing removed following the algorithm}
     \end{subfigure}
@@ -445,12 +447,12 @@ figure~\onpage{fig:selfcrossing-1-non-neighbor}.
 
 \begin{figure}[h]
     \centering
-    \begin{subfigure}[b]{.4\textwidth}
+    \begin{subfigure}[b]{.45\textwidth}
         \includegraphics[width=\textwidth]{selfcrossing-1-before}
         \caption{Bend's baseline (dotted) is crossing a non-neighboring bend}
     \end{subfigure}
     \hfill
-    \begin{subfigure}[b]{.4\textwidth}
+    \begin{subfigure}[b]{.45\textwidth}
         \includegraphics[width=\textwidth]{selfcrossing-1-after}
         \caption{Self-crossing removed following the algorithm}
     \end{subfigure}