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\documentclass{beamer}
\usepackage[utf8x]{inputenc}
% \usetheme[secheader]{Boadilla}
% \usetheme[secheader]{Goettingen}
\usetheme{Malmoe}
\definecolor{myblue}{RGB}{55,69,104}
\usecolortheme[named=myblue]{structure}
\useinnertheme{circles}
\usepackage{hyperref}
\usepackage{ngerman}
\newenvironment{slide}[1]{\begin{frame}[containsverbatim]{#1}}{\end{frame}}
\usepackage{color}
\usepackage{listings}
\usepackage{pgfpages}
\definecolor{mylightgray}{rgb}{0.91,0.91,0.91}
\lstset{
basicstyle=\ttfamily\tiny,
language=,
showstringspaces=false,
numbers=none,
numberstyle=\tiny,
stepnumber=2,
emptylines=*1,
breaklines=false,
frame=none,
columns=fixed,
% escapechar={},
% extendedchars=true,
commentstyle=\it\color{gray},
directivestyle=\color{green},
stringstyle=\color{red},
backgroundcolor=\color{mylightgray},
keywordstyle=\bf\color{black}
}
\title{xf86-input-joystick}
\author{\textbf{Sascha Hlusiak}}
\logo{\includegraphics[width=1cm,height=1cm]{pics/X_Org_Logo.png}}
\titlegraphic{\includegraphics[width=4cm,height=4cm]{pics/logitech_1.png}}
%\institute{}
%\date{}%{}
%% ABSTRACT
%The joystick input module was part of the old XFree86 distribution, but the
%driver was in a bad state until 2007, when development was pushed forward. It
%first supported the Linux joystick kernel device only, later on support for
%evdev devices was added, which added support for the driver to be hotplugged
%by hal enabled server. A FreeBSD kernel backend is available as well, but
%like Solaris, this is not a prominent system on workstations. Today the
%joystick driver is well hotpluggable using udev and supports many features
%and configuration possibilities, like generating mouse button events, pointer
%movement or key strokes. Enabling the driver to act as both, a pointer and a
%keyboard device, was particularly challenging. Having a second keyboard
%device with a different keyboard layout was a problem too, but situation
%improved with recent servers and XI2/MPX. Support for properties enable 3rd
%party programs to be written that change the configuration of the device on
%demand. Prominent target platforms are Linux on the PS3 or the XBox.
\begin{document}
\maketitle
\section*{Overview}
\subsection*{Abstract}
\begin{slide}{Abstract}
\structure{xf86-input-joystick?}
\begin{itemize}
\item input module for the X.Org server to handle joystick devices
\item can emit cursor movement and key events
\item \textbf{control the cursor with a joystick}
\end{itemize}
\end{slide}
\begin{slide}{Overview}
\tableofcontents
\end{slide}
\section{Basics}
\begin{slide}{joysticks}
\begin{itemize}
\item easily 6 or more axes, different types
\begin{itemize}
\item directional pad
\item hat switch
\item analog sticks
\end{itemize}
\item bunch of buttons, easily 10 and more
\item sometimes force feedback
\end{itemize}
\begin{center}
\includegraphics[width=4cm,height=4cm]{pics/logitech_1.png}
\end{center}
\end{slide}
\begin{slide}{why a joystick input module?}
\begin{itemize}
\item \textbf{xf86-input-evdev} maps directly to mouse/keyboard events
\item evdev only in Linux
\item joysticks send absolute axis data \\
$ \Rightarrow $ direct mapping useless \\
$ \Rightarrow $ want smooth, relative cursor movement \\
\item joystick specific event transformation:
\end{itemize}
\scriptsize \vspace{1cm}
$$
\underbrace{
\left (
\begin{matrix}
\text{absolute axes} \\
\text{buttons} \\
\end{matrix}
\right )
}_{\text{joystick data}}
\Rightarrow
\underbrace{
px(a_i) = \int_{t} f(a_i) \frac{\mathrm{px}}{\mathrm{s}}
}_{\text{transformation}}
\Rightarrow
\underbrace{
\left (
\begin{matrix}
\text{cursor} \\
\text{buttons} \\
\text{keys} \\
\end{matrix}
\right )
}_{\text{X events}}
$$
\end{slide}
\begin{slide}{joysticks on kernel level}
\structure{kernel device}
\begin{itemize}
\item usually Plug \& Play (USB)
\item event driven $ \Rightarrow $ no polling
\end{itemize}
\structure{Linux}
\begin{itemize}
\item \texttt{/dev/input/js0} (joydev)
\item \texttt{/dev/input/event0} (evdev)
\end{itemize}
\structure{FreeBSD}
\begin{itemize}
\item \texttt{/dev/input/js0} (linux-js)
\item \texttt{/dev/uhid0} (usbhid)
\end{itemize}
$ \Rightarrow $ supported through lightweight abstraction layer
\end{slide}
\section{Backends}
\section{Hotplugging}
\section{Main Features}
\section{Properties}
\section{Future}
\end{document}
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