\begin{table}
\begin{tabular}{|l|l|l|} \hline
format and location &  vertices (\% reduction) & polygons (\% reduction) \\ \hline
dense & 16384 & 32258 \\ \hline
sparse 90Km NW of Albany & 14836 (9.4\%) & 29203 (9.5\%) \\ \hline
sparse Albany & 10693 (34.7\%) & 21023 (34.8\%) \\ \hline
\end{tabular}
\caption{Reduction on number of vertices and polygons
\label{VRML-reduction}}
\end{table}

\begin{table}
\begin{tabular}{|l|l|l|l|} \hline
model threshold & wavelet coefficients & vertices & polygons \\
\hline
0 & 4946 & 14836 & 29203 \\ \hline
5 & 3418 & 10277 & 20170 \\ \hline
10 & 2523 & 7590 & 14869 \\ \hline
20 & 1393 & 4197 & 8184 \\ \hline
40 & 609 & 1834 & 3520 \\ \hline
80 & 278 & 836 & 1570 \\ \hline
\end{tabular}
\caption{The table shows the number of wavelet coefficients, vertices and
polygons of different model of 90Km NW of Albany\label{VRML-size}}
\end{table}

\begin{figure}
\begin{center}
\begin{picture}(110,468)
\psfig{figure=90NW_dense.ps,width=110pt,height=468pt}
\end{picture}
\
\begin{picture}(110,468)
\psfig{figure=90NW_000.ps,width=160pt,height=468pt}
\end{picture}
\end{center}
\caption{The dense (upper image) and the spares (lower image) terrain model of
the area 90Km NW of Albany is shown. The coordinate of the bounding box is
(73:22:35W 43:16:38N) for the upper lefthand corner and (73:32:07W 43:11:31N)
for the lower righthand corner. \label{90NW_sparse_0}}
\end{figure}

\begin{figure}
\begin{center}
\begin{picture}(143,468)
\psfig{figure=Albany_000.ps,width=143pt,height=468pt}
\end{picture}
\end{center}
\caption{Sparse terrain model of the Albany is shown.  The coordinate of the
bounding box is (74:00:48W 42:38:59N) for the upper lefthand corner and
(74:10:12W 42:32:09N)
for the lower righthand corner. Albany is located at (73:35:24W 42:39:09N).
\label{Albany_sparse_0}}
\end{figure}

\begin{figure}
\begin{center}
\begin{picture}(110,468)
\psfig{figure=90NW_dense.ps,width=110pt,height=468pt}
\end{picture}
\
\begin{picture}(146,468)
\psfig{figure=90NW_005.ps,width=146pt,height=468pt}
\end{picture}
\end{center}

\caption{The dense (upper image) and the sparse (lower image) terrain model of
the area 90Km NW of Albany is shown.  The sparse model is generated with
threshold set to 5. \label{90NW_sparse_5}}
\end{figure}

\begin{figure}
\begin{center}
\begin{picture}(110,468)
\psfig{figure=90NW_dense.ps,width=110pt,height=468pt}
\end{picture}
\
\begin{picture}(132,468)
\psfig{figure=90NW_010.ps,width=132pt,height=468pt}
\end{picture}
\end{center}

\caption{The dense (upper image) and the sparse (lower image) terrain model of
the area 90Km NW of Albany is shown.  The sparse model is generated with
threshold set to 10. \label{90NW_sparse_10}}
\end{figure}

\begin{figure}
\begin{center}
\begin{picture}(110,468)
\psfig{figure=90NW_dense.ps,width=110pt,height=468pt}
\end{picture}
\
\begin{picture}(138,468)
\psfig{figure=90NW_020.ps,width=138pt,height=468pt}
\end{picture}
\end{center}

\caption{The dense (upper image) and the sparse (lower image) terrain model of
the area 90Km NW of Albany is shown.  The sparse model is generated with
threshold set to 20. \label{90NW_sparse_20}}
\end{figure}

\begin{figure}
\begin{center}
\begin{picture}(110,468)
\psfig{figure=90NW_dense.ps,width=110pt,height=468pt}
\end{picture}
\
\begin{picture}(136,468)
\psfig{figure=90NW_040.ps,width=136pt,height=468pt}
\end{picture}
\end{center}

\caption{The dense (upper image) and the sparse (lower image) terrain model of
the area 90Km NW of Albany is shown.  The sparse model is generated with
threshold set to 40. \label{90NW_sparse_40}}
\end{figure}

\begin{figure}
\begin{center}
\begin{picture}(110,468)
\psfig{figure=90NW_dense.ps,width=110pt,height=468pt}
\end{picture}
\
\begin{picture}(124,468)
\psfig{figure=90NW_080.ps,width=124pt,height=468pt}
\end{picture}
\end{center}

\caption{The dense (upper image) and the sparse (lower image) terrain model of
the area 90Km NW of Albany is shown.  The sparse model is generated with
threshold set to 80. \label{90NW_sparse_80}}
\end{figure}


\section{Overview}
\section{Advantages}
\section{Disadvantages}
\section{Terrain}
