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 \chapter{Usage}\label{ch:usage}
+
+% Maybe this is too much of a guide, but I think a section with the user's
+% description should be present and there is not much other content to write
+% here. Also, the UI is currently horrible, so it is worth having this
+% somewhere, and since there is no documentation, here is the place probably.
+
+In this chapter we describe the program from the user's point of view and
+present its features.
+
+\section{Running Birdvisu}
+
+First, the user needs to obtain Birdvisu from somewhere. Either, the
+attachment~\ref{att:birdvisu} can be extracted, or the project can be
+downloaded from its repository at
+\url{https://gitea.ledoian.cz/LEdoian/birdvisu}, which will also contain any
+future improvements.
+
+The only strict dependency of Birdvisu is Python3.10 or newer. While the project
+depends on the PySide6 library for the user interface, it can be downloaded
+as a wheel\X{glos} from PyPI. Of course, using a system-wide installation of
+PySide6 is also possible.
+
+Birdvisu can read the topology information from files, so it is not necessary
+to have a BIRD running and configured if only showing static data is required.
+
+We only support running the project on Linux. However, Birdvisu might be able
+to run on other types of operating systems, since we have only used
+cross-platform libraries.
+
+There are several ways to start the program. The recommended method is to
+install the project into a Python virtual environment, but running the
+\verb|visu.py| script also works when PySide6 is installed in the system.\X{uuuuuuuuuuu!!}
+
+Once the program is started, the user is presented with an empty canvas. Using
+the \emph{Topology} menu, it is possible to load both a reference and current
+topologies. Both can be loaded from a file, the current one can also be
+retrieved directly from a running BIRD via its socket. In the latter case, the
+user is provided with a dialog to pick an area and OSPF instance.
+
+Once both topologies are loaded, the graph of the topolgy appears. Now, the
+vertices can be moved around to the user's liking. Alternatively, the
+\emph{Positions} menu provides a way to load the positions of vertices from a file.
+
+The program expects the topology files to have the \verb|.ospf| extension,
+positioning files may end in \verb|.visu|. Nevertheless, any files may be used,
+they just are not offered by default.
+
+Several highlighting ways are available. In the \emph{Highlight} menu, the user
+can choose to show differences between the reference and current topology, or
+set the widths of edges according to their costs. Alternatively, by
+right-clicking any vertex, it is possible to highlight its shortest path DAG.
+If the user wants to find a specific route, showing the DAG also serves as
+selecting the start vertex. The context menus for vertices then allow finding
+the path to those vertices.
+
+Finally, there is an option to reload the shown graph in the Topology menu. We
+decided that the graph should not change unexpectedly, because that could be
+unpleasant to use.
+
+As a part of Birdvisu we ship the files \verb|gennet.ospf|,
+\verb|gennet-changed.ospf| and \verb|gennet.visu| for demonstration purposes.
+These files provide a topology of the default Gennet, the same topology with
+several manual changes, and a placement of vertices like in figure~\ref{fig:gennet}.
+
+\iffalse
+\section{Extending Birdvisu}
+\fi