1101 |
%the output values can be scaled up only once per each general |
%the output values can be scaled up only once per each general |
1102 |
%combiner stage by at most 4. |
%combiner stage by at most 4. |
1103 |
|
|
|
\begin{figure*} |
|
|
\centering |
|
|
\ifpics |
|
|
\includegraphics[height=10cm]{multipaper.ps} |
|
|
\fi |
|
|
\caption{ |
|
|
\label{fig-examples} |
|
|
A number of unique backgrounds generated by our system. |
|
|
This view can be rendered, without pre-rendering the textures, |
|
|
in 20 ms on a GeForce4 Ti 4200 in a 1024x768 window (fill-rate/bandwidth limited). |
|
|
} |
|
|
\end{figure*} |
|
|
|
|
1104 |
\begin{figure} |
\begin{figure} |
1105 |
\centering |
\centering |
1106 |
\ifpics |
\ifpics |
1171 |
\end{figure*} |
\end{figure*} |
1172 |
|
|
1173 |
\section{Experiences, evaluation} |
\section{Experiences, evaluation} |
1174 |
In the following, we evaluate the implications and tradeoffs |
|
1175 |
of different |
%In the following, we evaluate the implications and tradeoffs |
1176 |
aspects in the use of unique backround textures. |
%of different |
1177 |
|
%aspects in the use of unique backround textures. |
1178 |
|
|
1179 |
\subsection{Overall appearance of the resulting textures} |
\subsection{Overall appearance of the resulting textures} |
1180 |
|
|
1181 |
|
As seen in Fig.~\ref{fig-examples}, the overall appearance of the textures |
1182 |
|
is somewhat natural and the textures clearly do have unique distinguishing |
1183 |
|
features. |
1184 |
|
|
1185 |
|
\begin{figure*} |
1186 |
|
\centering |
1187 |
|
\ifpics |
1188 |
|
\includegraphics[height=10cm]{multipaper.ps} |
1189 |
|
\fi |
1190 |
|
\caption{ |
1191 |
|
\label{fig-examples} |
1192 |
|
A number of unique backgrounds generated by our system. |
1193 |
|
This view can be rendered, without pre-rendering the textures, |
1194 |
|
in 20 ms on a GeForce4 Ti 4200 in a 1024x768 window (fill-rate/bandwidth limited). |
1195 |
|
} |
1196 |
|
\end{figure*} |
1197 |
|
|
1198 |
|
The can be zoomed quite well, |
1199 |
|
even though |
1200 |
|
we have not tried to attain infinite zoomability\cite{furnas00infinity} |
1201 |
|
with the current implementation, |
1202 |
|
but only the more modest goal of zooming within a range |
1203 |
|
that would be reasonable for a single PDF document, |
1204 |
|
i.e., approximately 20-fold |
1205 |
|
difference between mininum and maximum zoom. |
1206 |
|
|
1207 |
%The background textures should be be recognizable at different scales. |
%The background textures should be be recognizable at different scales. |
1208 |
Although texture perception is scale-independent to some extent, |
Although texture perception is scale-independent to some extent, |
1209 |
the display resolution and certain spatial interactions |
the display resolution and certain spatial interactions |
1215 |
so that the resulting textures have separate |
so that the resulting textures have separate |
1216 |
distinguishing features on both small and large scales. |
distinguishing features on both small and large scales. |
1217 |
|
|
|
We have not tried to attain infinite zoomability\cite{furnas00infinity} |
|
|
with the current implementation, |
|
|
but only the more modest goal of zooming within a range |
|
|
that would be reasonable for a single PDF document, |
|
|
i.e., approximately 10-fold |
|
|
difference between mininum and maximum zoom. |
|
1218 |
% This is in line with our |
% This is in line with our |
1219 |
% intended use, since it would be unreasonable |
% intended use, since it would be unreasonable |
1220 |
% to expect a texture to be recognizable |
% to expect a texture to be recognizable |
1223 |
to make the unique background look similar |
to make the unique background look similar |
1224 |
at different scales, but |
at different scales, but |
1225 |
this would remove the use of the texture as a cue of scale. |
this would remove the use of the texture as a cue of scale. |
1226 |
|
|
1227 |
Our |
Our |
1228 |
nonlinear use of the register combiners |
nonlinear use of the register combiners |
1229 |
does have some ill effects when zooming the texture out |
does have some ill effects when zooming the texture out |