more stage clarifications
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@ -5,7 +5,9 @@
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\usepackage[english]{babel}
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\usepackage[english]{babel}
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\usepackage[utf8]{inputenc}
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\usepackage[utf8]{inputenc}
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\usepackage{a4wide}
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\usepackage{a4wide}
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\usepackage{csquotes}
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%\usepackage{csquotes}
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\usepackage [autostyle, english = american]{csquotes}
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\MakeOuterQuote{"}
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\usepackage[maxbibnames=99,style=authoryear]{biblatex}
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\usepackage[maxbibnames=99,style=authoryear]{biblatex}
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\usepackage[pdfusetitle]{hyperref}
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\usepackage[pdfusetitle]{hyperref}
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\usepackage{enumitem}
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\usepackage{enumitem}
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@ -270,24 +272,53 @@ purposes) using the following algorithm:
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\section{Definition of a Bend}
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\section{Definition of a Bend}
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\label{sec:definition-of-a-bend}
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\label{sec:definition-of-a-bend}
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The original article describes:
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\begin{displayquote}[\cite{wang1998line}][]
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A bend can be defined as that part of a line which contains a number of
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subsequent vertices, with the inflection angles on all vertices included in
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the bend being either positive or negative and the inflection of the bend's
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two end vertices being in opposite signs.
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\end{displayquote}
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While it gives a good intuitive understanding of what the bend is, some more
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technical details would be appreciated.
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Figure~\ref{fig:fig8-definition-of-a-bend} illustrates article's figure 8,
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but with bends colored as polygons: each color is a distinctive bend.
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\begin{figure}[h]
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\begin{figure}[h]
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\centering
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\centering
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\includegraphics[width=\linewidth]{fig8-definition-of-a-bend}
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\includegraphics[width=\linewidth]{fig8-definition-of-a-bend}
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\caption{Originally Figure 8: detected bends are highlighted}
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\caption{Originally figure 8: detected bends are highlighted}
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\label{fig:fig8-definition-of-a-bend}
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\label{fig:fig8-definition-of-a-bend}
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\end{figure}
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\end{figure}
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End line segments of all lines should also be part of the bend. That way, all
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Once the intuitive definition is established, here are some non-obvious
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line segments belong to 1 or 2 bends. This characteristic is not obvious when
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characteristics that are necessary when writing code to detect the bends:
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reading the introductory sections, but becomes unavoidable (there could be no
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other way) when reading the following sections in detail.
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First and last segments of each bend (except for the two end-line segments) is
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\begin{itemize}
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also the first vertex of the next bend. This is apparent when looking at the
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illustration of the detected bends.
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\item End segments of each line should also belong to bends. That way, all
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segments belong to 1 or 2 bends.
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\item First and last segments of each bend (except for the two end-line
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segments) is also the first vertex of the next bend.
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\end{itemize}
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Properties above may be apparent when looking at illustrations at this article
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or reading here, but they are nowhere as such when looking at the original
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article.
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\section{Gentle Inflection at End of a Bend}
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\section{Gentle Inflection at End of a Bend}
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The gist of the section is in the original article:
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\begin{displayquote}[\cite{wang1998line}][]
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But if the inflection that marks the end of a bend is quite small, people
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would not recognize this as the bend point of a bend
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\end{displayquote}
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Figure~\ref{fig:fig5-gentle-inflection} visualizes original paper's Figure 5,
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Figure~\ref{fig:fig5-gentle-inflection} visualizes original paper's Figure 5,
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when a single vertex is moved outwards the end of the bend.
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when a single vertex is moved outwards the end of the bend.
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@ -302,20 +333,21 @@ when a single vertex is moved outwards the end of the bend.
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\includegraphics[width=\textwidth]{fig5-gentle-inflection-after}
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\includegraphics[width=\textwidth]{fig5-gentle-inflection-after}
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\caption{After applying the inflection rule}
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\caption{After applying the inflection rule}
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\end{subfigure}
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\end{subfigure}
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\caption{Originally Figure 5: gentle inflections at the ends of the bend}
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\caption{Originally figure 5: gentle inflections at the ends of the bend}
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\label{fig:fig5-gentle-inflection}
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\label{fig:fig5-gentle-inflection}
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\end{figure}
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\end{figure}
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The example in this section was clear, but insufficient: it does not specify
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The illustration for this section was clear, but insufficient: it does not
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how many vertices should be included when calculating the end-of-bend
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specify how many vertices should be included when calculating the end-of-bend
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inflection. We chose the iterative approach -- as long as the angle is "right"
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inflection. We chose the iterative approach --- as long as the angle is "right"
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and the distance is decreasing, the algorithm should keep re-assigning vertices
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and the distance is decreasing, the algorithm should keep re-assigning vertices
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to different bends; practically not having an upper bound on the number of
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to different bends; practically not having an upper bound on the number of
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iterations.
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iterations.
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Additional example, not found in the original paper, is illustrated in
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To prove that the algorithm implementation is correct for multiple vertices,
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figure~\ref{fig:inflection-1-gentle-inflection}, which re-assigns two vertices
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additional example was created, and illustrated in
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to the next bend instead of one.
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figure~\ref{fig:inflection-1-gentle-inflection}: the rule re-assigns two
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vertices to the next bend instead of one.
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\begin{figure}[h]
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\begin{figure}[h]
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\centering
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\centering
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