868 |
For readability, we only use colors with the CIE $L^*$ value over 80. |
For readability, we only use colors with the CIE $L^*$ value over 80. |
869 |
Note that the display gamma interacts with the lightness computation: |
Note that the display gamma interacts with the lightness computation: |
870 |
we have adjusted the computations for a display gamma of 2.2, |
we have adjusted the computations for a display gamma of 2.2, |
871 |
which is typically the default (with gamma correction 1.0) in PC systems. |
which is typically the default %(with gamma correction 1.0) |
872 |
|
in PC systems. |
873 |
%Note that for correct computation of the lightness, |
%Note that for correct computation of the lightness, |
874 |
%it is essential that the display gamma is properly adjusted |
%it is essential that the display gamma is properly adjusted |
875 |
%for linear (XXX: usually around gamma 2) RGB reproduction. |
%for linear (XXX: usually around gamma 2) RGB reproduction. |
1032 |
% the gradients and to diminish the area from which the features |
% the gradients and to diminish the area from which the features |
1033 |
% of a single basis texture are extracted. |
% of a single basis texture are extracted. |
1034 |
|
|
1035 |
Because some basis texture have blurrier edges than others, |
Because some basis textures have blurrier edges than others, |
1036 |
the output scalings need to be adjusted depending on the basis |
the output scalings need to be adjusted depending on the basis |
1037 |
textures selected. |
textures selected. |
1038 |
|
|
1135 |
\end{figure*} |
\end{figure*} |
1136 |
|
|
1137 |
\section{Experiences, evaluation} |
\section{Experiences, evaluation} |
|
|
|
1138 |
It can be argued that |
It can be argued that |
1139 |
the backgrounds clutter the display |
the backgrounds clutter the display |
1140 |
visually, making the user interface more confusing, |
visually, making the user interface more confusing, |
1141 |
|
and may not even be helpful. |
1142 |
|
Indeed, many aspects of the system are a compromise between |
1143 |
|
recognizability and some other goal such as readability, rendering |
1144 |
|
performance, or a less well-defined goal such as user comfortability. |
1145 |
|
|
1146 |
|
Overall, we feel that the backgrounds can greatly improve user orientation, |
1147 |
|
enabling more efficient views to hyperstructured content, and |
1148 |
|
therefore the benefits outweigh the costs. |
1149 |
|
In the following, we evaluate the implications and tradeoffs |
1150 |
|
of different |
1151 |
|
aspects in the use of unique backround textures. |
1152 |
|
|
1153 |
\subsection{Overall appearance of the resulting textures} |
\subsection{Overall appearance of the resulting textures} |
1154 |
|
|
1155 |
%XXX: Furthermore, because the texture appearance has no correlation |
The most important point is generating the backgrounds is that |
1156 |
%with the document content, |
the texture appearance should have no correlation with any attribute |
1157 |
%the textures of any two important files are similar only by chance. |
or content of the document |
1158 |
|
so that the textures of any two important files |
1159 |
|
are similar only by chance. |
1160 |
|
Having any semantics encoded in the appearance of the textures |
1161 |
|
would prohibit orthogonal structures with differing semantics |
1162 |
|
of the same content. |
1163 |
|
|
1164 |
|
Zoomability: |
1165 |
|
|
1166 |
%The background textures should be be recognizable at different scales. |
%The background textures should be be recognizable at different scales. |
1167 |
Although texture perception is scale-independent to some extent, |
Although texture perception is scale-independent to some extent, |