\chapter*{Conclusion}
\markboth{Preface}{Conclusion}
\addcontentsline{toc}{chapter}{Conclusion}
The aim of my work was to design and implement visualization methods for facial comparison in order to extend the visualization techniques currently provided in FIDENTIS Analyst application -- an application for facial analysis used by anthropology scientists.

In order to do so, I first analyzed the visualizations currently provided in the application and discussed with scientists the needs of the applications, the areas they would like to explore in greater detail and their expectations for the new visualizations. With the help of scientists I put together the list of issues I then attempted to solve when designing the visualizations.

Based on this list I conducted a research of related work in area of 3D data visualization, comparative visualization and visual analysis of cohort study data. I looked for principles that could by applicable for facial data and provide solution to the issues at hand.

I then presented the results of my research to anthropologists. Together we selected several techniques that served as bases for my work. I adjusted them to meet the needs of input data and better address the problems. I chose and implemented three different approaches of visualization.

For scenarios where two models are processed and compared, I chose superposition principle -- placing the two models on top of each other -- and implemented several adjustments and cues to improve the shape and distance perceptibility. Namely I implemented intersection contours detection and highlight, surface opacity modulation based on its position in regards to viewer, shadow-casting glyphs indicating surface curvature and simulation of fog based on the distance between surfaces.

Another method I designed in order to visualize local variability and shape is based on cross-sectional slices. This technique transfers the local data from 3D to 2D view, which reduces visual complexity and allows the observer to focus on important details. 

The third and final tool I created employs heat maps for visualization of numerical data exported from the application. The purpose of this tool is to reduce the need for further data post-process\-ing in other applications and provide yet another outlook on data.

After implementing these techniques I conducted a user study with scientists working in the area of facial analysis to evaluate the contribution of my visualizations to the area. The results showed the scientists found most of the presented visualization techniques contributory, three of them -- surface superimposition method with shadow-casting glyphs, cross-sectional slices and heat plot for numerical data -- particularly so, marking them as visualization of choice for several tasks they usually perform during their work.

The standalone application with the visualization tools I created is already used by the scientists. In the nearest future I am going to integrate the visualization techniques into FIDENTIS Analyst application, where they could aid the process of facial analysis as well as communicate the results. I would also like to implement the suggestions for improvement and extensions made by scientists during evaluation process -- mainly the view independent fog simulation and the auxiliary results heat plot extension for displaying the location of the data on the model.