more analysis for 1:50k and 1:250k.

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Motiejus Jakštys 2021-05-15 16:35:33 +03:00
parent 7f00d9f372
commit c3807a1c50
2 changed files with 86 additions and 25 deletions

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@ -40,8 +40,10 @@ RIVERS = \
salvis-visvalingam-64-chaikin-50k \ salvis-visvalingam-64-chaikin-50k \
salvis-overlaid-douglas-64-chaikin-50k \ salvis-overlaid-douglas-64-chaikin-50k \
salvis-overlaid-visvalingam-64-chaikin-50k \ salvis-overlaid-visvalingam-64-chaikin-50k \
salvis-wm-75-50k \ salvis-wm-50k \
salvis-wm-220-250k salvis-wm-250k \
salvis-wm-overlaid-50k-zoom \
salvis-wm-overlaid-250k-zoom
################################# #################################
# The thesis, publishable version # The thesis, publishable version
@ -193,15 +195,19 @@ salvis-overlaid-visvalingam-64-chaikin-50k_1COLOR = orange
salvis-overlaid-visvalingam-64-chaikin-50k_WIDTHDIV = 2 salvis-overlaid-visvalingam-64-chaikin-50k_WIDTHDIV = 2
salvis-overlaid-visvalingam-64-chaikin-50k_QUADRANT = 1 salvis-overlaid-visvalingam-64-chaikin-50k_QUADRANT = 1
salvis-wm-75-50k_1SELECT = wm_visuals where name='salvis' salvis-wm-50k_1SELECT = wm_visuals where name='salvis-wm-75'
salvis-wm-75-50k_2SELECT = wm_visuals where name='salvis-wm-75' salvis-wm-50k_WIDTHDIV = 2
salvis-wm-75-50k_1COLOR = orange
salvis-wm-75-50k_WIDTHDIV = 2
salvis-wm-220-250k_1SELECT = wm_visuals where name='salvis' salvis-wm-250k_1SELECT = wm_visuals where name='salvis-wm-220'
salvis-wm-220-250k_2SELECT = wm_visuals where name='salvis-wm-220' salvis-wm-250k_WIDTHDIV = 10
salvis-wm-220-250k_1COLOR = orange
salvis-wm-220-250k_WIDTHDIV = 2 salvis-wm-overlaid-50k-zoom_1SELECT = wm_visuals where name='salvis'
salvis-wm-overlaid-50k-zoom_2SELECT = wm_visuals where name='salvis-wm-75'
salvis-wm-overlaid-50k-zoom_1COLOR = orange
salvis-wm-overlaid-250k-zoom_1SELECT = wm_visuals where name='salvis'
salvis-wm-overlaid-250k-zoom_2SELECT = wm_visuals where name='salvis-wm-220'
salvis-wm-overlaid-250k-zoom_1COLOR = orange
.faux_db: db init.sql rivers.sql .faux_db: db init.sql rivers.sql
bash db start bash db start

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@ -1333,34 +1333,89 @@ the algorithm.
\subsection{Generalization results of Analyzed Rivers} \subsection{Generalization results of Analyzed Rivers}
Figure~\ref{fig:salvis-wm-75-50k} visualizes the generalization result for Figures~\ref{fig:salvis-wm-50k} and~\ref{fig:salvis-wm-250k} visualize
Šalčia and Visinčia using {\WM} with the \textsc{dhalfcircle} values from the generalization result for Šalčia and Visinčia using {\WM} with the
the table~\ref{table:scale-halfcirlce-diameter}: \textsc{dhalfcircle} values from the
table~\ref{table:scale-halfcirlce-diameter}:
\begin{itemize} \begin{itemize}
\item 1:\numprint{50000}: 75 (figure~\ref{fig:salvis-wm-75-50k}). \item 1:\numprint{50000}: 75.
\item 1:\numprint{250000}: 220 (figure~\ref{fig:salvis-wm-220-250k}). \item 1:\numprint{250000}: 220.
\end{itemize} \end{itemize}
The original feature is orange. As can be seen, some \subsubsection{Mid-scale (1:\numprint{50000})}
isolated bends are exaggerated, and some small bends are removed.
\begin{figure}[ht] \begin{figure}[ht]
\centering \centering
\includegraphics[width=.5\textwidth]{salvis-wm-75-50k} \begin{subfigure}[b]{.49\textwidth}
\caption{{\WM}-generalized river (1:{\numprint{50000}}).} \includegraphics[width=\textwidth]{salvis-50k}
\label{fig:salvis-wm-75-50k} \caption{Original.}
\end{subfigure}
\hfill
\begin{subfigure}[b]{.49\textwidth}
\centering
\includegraphics[width=\textwidth]{salvis-wm-50k}
\caption{Simplified.}
\end{subfigure}
\caption{Simplified with {\WM} for 1:\numprint{50000}.}
\label{fig:salvis-wm-50k}
\end{figure}
As one can see in figure~\ref{fig:salvis-wm-50k}, some of the small bends have
been exaggerated, and some removed. It mostly works as expected, except some of
the jagged lines approximately in the middle of the figure.
Figure~\ref{fig:salvis-wm-50k-overlaid-zoom} zooms in, overlaying the original
river (in orange).
\begin{figure}[ht]
\centering
\includegraphics[width=\textwidth]{salvis-wm-overlaid-50k-zoom}
\caption{2x zoomed-in {\WM} for 1:\numprint{50000}.}
\label{fig:salvis-wm-50k-overlaid-zoom}
\end{figure}
These will become
more pronounced in large-scale simplification in the next section. Other than
some sharp edges, this algorithm works reasonably well for mid-scale
simplification.
\subsubsection{Large-scale (1:\numprint{250000})}
As visible in figure~\ref{fig:salvis-wm-250k}, for large-scale map, some of the
resulting bends look significantly exaggerated. Why is that?
Figure~\ref{fig:salvis-wm-250k-overlaid-zoom} zooms in the large-scale
simplification and overlays the original (in orange).
\begin{figure}[ht]
\centering
\begin{subfigure}[b]{.49\textwidth}
\centering
\includegraphics[width=.2\textwidth]{salvis-250k}
\caption{Original.}
\end{subfigure}
\hfill
\begin{subfigure}[b]{.49\textwidth}
\centering
\includegraphics[width=.2\textwidth]{salvis-wm-250k}
\caption{Simplified.}
\end{subfigure}
\caption{Simplified with {\WM} for 1:\numprint{250000}.}
\label{fig:salvis-wm-250k}
\end{figure} \end{figure}
\begin{figure}[ht] \begin{figure}[ht]
\centering \centering
\includegraphics[width=.5\textwidth]{salvis-wm-220-250k} \includegraphics[width=\textwidth]{salvis-wm-overlaid-250k-zoom}
\caption{{\WM}-generalized river (1:{\numprint{250000}}).} \caption{10x zoomed-in {\WM} for 1:\numprint{250000}.}
\label{fig:salvis-wm-220-250k} \label{fig:salvis-wm-250k-overlaid-zoom}
\end{figure} \end{figure}
% TODO: expand section and remove clear-page. A conglomeration of bends is visible, especially in north-east side of the
\clearpage center. We assume this was caused by two bends significantly exaggerated,
leaving no space to exaggerate for those between the two. For the same reason,
the 1:\numprint{50000} figure~\ref{fig:salvis-wm-50k} has many smaller bends
at approximately the same location.
\subsection{Generalization result comparison with national spatial data sets} \subsection{Generalization result comparison with national spatial data sets}