more explanations
This commit is contained in:
parent
76b2a1cde2
commit
0a94a47fa1
24
Makefile
24
Makefile
@ -40,9 +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-50k \
|
|
||||||
salvis-wm-250k \
|
salvis-wm-250k \
|
||||||
salvis-wm-overlaid-50k-zoom \
|
salvis-wm-50k \
|
||||||
|
salvis-wm-50k-nw \
|
||||||
|
salvis-wm-50k-ne \
|
||||||
salvis-wm-overlaid-250k-zoom \
|
salvis-wm-overlaid-250k-zoom \
|
||||||
salvis-gdr50-overlaid
|
salvis-gdr50-overlaid
|
||||||
|
|
||||||
@ -199,15 +200,22 @@ 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-50k_1SELECT = wm_visuals where name='salvis-wm-75'
|
|
||||||
salvis-wm-50k_WIDTHDIV = 2
|
|
||||||
|
|
||||||
salvis-wm-250k_1SELECT = wm_visuals where name='salvis-wm-220'
|
salvis-wm-250k_1SELECT = wm_visuals where name='salvis-wm-220'
|
||||||
salvis-wm-250k_WIDTHDIV = 10
|
salvis-wm-250k_WIDTHDIV = 10
|
||||||
|
|
||||||
salvis-wm-overlaid-50k-zoom_1SELECT = wm_visuals where name='salvis-wm-75'
|
salvis-wm-50k_1SELECT = wm_visuals where name='salvis-wm-75'
|
||||||
salvis-wm-overlaid-50k-zoom_2SELECT = wm_visuals where name='salvis'
|
salvis-wm-50k_2SELECT = wm_visuals where name='salvis'
|
||||||
salvis-wm-overlaid-50k-zoom_1COLOR = orange
|
salvis-wm-50k_1COLOR = orange
|
||||||
|
|
||||||
|
salvis-wm-50k-nw_1SELECT = wm_visuals where name='salvis-wm-75'
|
||||||
|
salvis-wm-50k-nw_2SELECT = wm_visuals where name='salvis'
|
||||||
|
salvis-wm-50k-nw_1COLOR = orange
|
||||||
|
salvis-wm-50k-nw_QUADRANT = 2
|
||||||
|
|
||||||
|
salvis-wm-50k-ne_1SELECT = wm_visuals where name='salvis-wm-75'
|
||||||
|
salvis-wm-50k-ne_2SELECT = wm_visuals where name='salvis'
|
||||||
|
salvis-wm-50k-ne_1COLOR = orange
|
||||||
|
salvis-wm-50k-ne_QUADRANT = 1
|
||||||
|
|
||||||
salvis-wm-overlaid-250k-zoom_1SELECT = wm_visuals where name='salvis-wm-220'
|
salvis-wm-overlaid-250k-zoom_1SELECT = wm_visuals where name='salvis-wm-220'
|
||||||
salvis-wm-overlaid-250k-zoom_2SELECT = wm_visuals where name='salvis'
|
salvis-wm-overlaid-250k-zoom_2SELECT = wm_visuals where name='salvis'
|
||||||
|
76
mj-msc.tex
76
mj-msc.tex
@ -1378,45 +1378,49 @@ table~\ref{table:scale-halfcirlce-diameter}:
|
|||||||
\subsubsection{Medium-scale (1:\numprint{50000})}
|
\subsubsection{Medium-scale (1:\numprint{50000})}
|
||||||
\label{sec:analyzed-medium-scale}
|
\label{sec:analyzed-medium-scale}
|
||||||
|
|
||||||
\begin{figure}[ht]
|
\begin{figure}[h!]
|
||||||
\centering
|
|
||||||
\begin{subfigure}[b]{.49\textwidth}
|
|
||||||
\includegraphics[width=\textwidth]{salvis-50k}
|
|
||||||
\caption{Original.}
|
|
||||||
\end{subfigure}
|
|
||||||
\hfill
|
|
||||||
\begin{subfigure}[b]{.49\textwidth}
|
|
||||||
\centering
|
\centering
|
||||||
\includegraphics[width=\textwidth]{salvis-wm-50k}
|
\includegraphics[width=\textwidth]{salvis-wm-50k}
|
||||||
\caption{Simplified.}
|
\caption{2x zoomed-in {\WM} for 1:\numprint{50000}.}
|
||||||
\end{subfigure}
|
|
||||||
\caption{Simplified with {\WM} for 1:\numprint{50000}.}
|
|
||||||
\label{fig:salvis-wm-50k}
|
\label{fig:salvis-wm-50k}
|
||||||
\end{figure}
|
\end{figure}
|
||||||
|
|
||||||
As one can see in figure~\ref{fig:salvis-wm-50k}, the illustrations deliver
|
As one can see in figure~\ref{fig:salvis-wm-50k}, the illustrations deliver
|
||||||
what was promised by the algorithm, but with a few caveats. West-side of the
|
what was promised by the algorithm, but with a few caveats. Left side of the
|
||||||
river looks reasonably well simplified: long bends remain slightly curved,
|
figure looks reasonably well simplified: long bends remain slightly curved,
|
||||||
small bends are removed or slightly exaggerated.
|
small bends are removed or slightly exaggerated.
|
||||||
|
|
||||||
Approximately at the middle of the figure some jagged and sharp bends appear.
|
Figure's~\ref{fig:salvis-wm-50k} left part is clipped to
|
||||||
Figure~\ref{fig:salvis-wm-50k-overlaid-zoom} zooms in, overlaying the original
|
figure~\ref{fig:salvis-wm-50k-nw}. As one can see, some bends were well
|
||||||
river (in orange). These will become more pronounced in even larger-scale
|
exaggerated, and some bends were eliminated.
|
||||||
|
|
||||||
|
\begin{figure}[h!]
|
||||||
|
\centering
|
||||||
|
\includegraphics[width=\textwidth]{salvis-wm-50k-nw}
|
||||||
|
\caption{Left part of figure~\ref{fig:salvis-wm-50k}.}
|
||||||
|
\label{fig:salvis-wm-50k-nw}
|
||||||
|
\end{figure}
|
||||||
|
|
||||||
|
Top--right side (clipped in figure~\ref{fig:salvis-wm-50k-ne}) some jagged
|
||||||
|
and sharp bends appear. These will become more pronounced in even larger-scale
|
||||||
simplification in the next section.
|
simplification in the next section.
|
||||||
|
|
||||||
\begin{figure}[ht]
|
\begin{figure}[h!]
|
||||||
\centering
|
\centering
|
||||||
\includegraphics[width=\textwidth]{salvis-wm-overlaid-50k-zoom}
|
\includegraphics[width=\textwidth]{salvis-wm-50k-ne}
|
||||||
\caption{2x zoomed-in {\WM} for 1:\numprint{50000}.}
|
\caption{Top--right part of figure~\ref{fig:salvis-wm-50k}.}
|
||||||
\label{fig:salvis-wm-50k-overlaid-zoom}
|
\label{fig:salvis-wm-50k-ne}
|
||||||
\end{figure}
|
\end{figure}
|
||||||
|
|
||||||
|
To sum up, mid-scale simplification works well for some geometries, but creates
|
||||||
|
sharp edges for others.
|
||||||
|
|
||||||
\subsubsection{Large-scale (1:\numprint{250000})}
|
\subsubsection{Large-scale (1:\numprint{250000})}
|
||||||
|
|
||||||
As visible in figure~\ref{fig:salvis-wm-250k}, for large-scale map, some of the
|
As visible in figure~\ref{fig:salvis-wm-250k}, for large-scale map, some of the
|
||||||
resulting bends look significantly exaggerated. Why is that?
|
resulting bends look significantly exaggerated. Why is that?
|
||||||
Figure~\ref{fig:salvis-wm-250k-overlaid-zoom} zooms in the large-scale
|
Figure~\ref{fig:salvis-wm-250k-overlaid-zoom} zooms in the large-scale
|
||||||
simplification and overlays the original (in orange).
|
simplification and overlays the original.
|
||||||
|
|
||||||
\begin{figure}[ht]
|
\begin{figure}[ht]
|
||||||
\centering
|
\centering
|
||||||
@ -1431,7 +1435,7 @@ simplification and overlays the original (in orange).
|
|||||||
\includegraphics[width=.2\textwidth]{salvis-wm-250k}
|
\includegraphics[width=.2\textwidth]{salvis-wm-250k}
|
||||||
\caption{Simplified.}
|
\caption{Simplified.}
|
||||||
\end{subfigure}
|
\end{subfigure}
|
||||||
\caption{Simplified with {\WM} for 1:\numprint{250000}.}
|
\caption{GDB10LT simplified with {\WM} for 1:\numprint{250000}.}
|
||||||
\label{fig:salvis-wm-250k}
|
\label{fig:salvis-wm-250k}
|
||||||
\end{figure}
|
\end{figure}
|
||||||
|
|
||||||
@ -1442,11 +1446,27 @@ simplification and overlays the original (in orange).
|
|||||||
\label{fig:salvis-wm-250k-overlaid-zoom}
|
\label{fig:salvis-wm-250k-overlaid-zoom}
|
||||||
\end{figure}
|
\end{figure}
|
||||||
|
|
||||||
A conglomeration of bends is visible, especially in north-east side of the
|
A conglomeration of bends is visible, especially in top--right side of the
|
||||||
center. We assume this was caused by two bends significantly exaggerated,
|
illustration. We assume this was caused by two bends significantly exaggerated,
|
||||||
leaving no space to exaggerate for those between the two. For the same reason,
|
leaving no space to exaggerate for those between the two.
|
||||||
the figure~\ref{fig:salvis-wm-50k} (of scale 1:\numprint{50000}) has many
|
|
||||||
smaller bends at approximately the same location.
|
\subsubsection{Discussion}
|
||||||
|
|
||||||
|
For mid-size scales of 1:\numprint{50000}, the implemented algorithm works well
|
||||||
|
for certain geometries, and poorly for others. This test surfaced two areas for
|
||||||
|
future research and improvement:
|
||||||
|
|
||||||
|
\begin{itemize}
|
||||||
|
|
||||||
|
\item Exaggeration is sometimes creating sharp edges, especially when the
|
||||||
|
exaggerated bend is quite small. When sharp edges are created,
|
||||||
|
exaggeration could interpolate more points in the bend, and exaggerate
|
||||||
|
using the interpolated points.
|
||||||
|
|
||||||
|
\item In larger scales, when bends do not have space to exaggerate, they
|
||||||
|
should be combined or eliminated instead.
|
||||||
|
|
||||||
|
\end{itemize}
|
||||||
|
|
||||||
\subsection{Comparing Generalized Result with National Spatial Datasets}
|
\subsection{Comparing Generalized Result with National Spatial Datasets}
|
||||||
|
|
||||||
@ -1547,7 +1567,7 @@ implementation:
|
|||||||
|
|
||||||
\item Fine-tune parameters for bend exaggeration.
|
\item Fine-tune parameters for bend exaggeration.
|
||||||
Section~\ref{sec:generalization-results-of-analyzed-rivers} contains
|
Section~\ref{sec:generalization-results-of-analyzed-rivers} contains
|
||||||
a exaggerated bends that became sharp.
|
a exaggerated bends that became sharp and includes some future ideas.
|
||||||
|
|
||||||
\item Research when bends should be marked as \textsc{isolated}. As is
|
\item Research when bends should be marked as \textsc{isolated}. As is
|
||||||
seen from examples, the current criteria is not robust enough.
|
seen from examples, the current criteria is not robust enough.
|
||||||
|
Loading…
Reference in New Issue
Block a user