== How do I access the sample source code for the Raspberry Pi and build the multimedia demo programs? ==
There are four multimedia demo programs available:* hello_world - the classic test program, that just prints "Hello, World!" on the screen* hello_video - a simple H.264 video player* hello_triangle - an OpenGL-ES demo program which displays a rolling cube with textures on each side* hello_audo - an audio demo that plays a sine wave with a slow sine wave amplitude modulation Here are the recommended steps for building these demo programs:# Ensure that the <code>raspberrypi-vc-demo-source</code> package is installed (it's installed in the released image).# Install the C/C++ toolchain. If you have sufficient space (about 600M), it's recommended that you install the full set of development tools and libraries (<code>yum groupinstall "Development Tools" "Development Libraries"</code>). Alternately, you could install a minimal set of tools (gcc, make, etc). (TODO: come up with the minimum set of tools/libraries needed for the demo code).# It's recommended that you build and run the code as a regular user:## Make a personal copy of the source code in your home directory: <code>cp -R /usr/share/raspberypi-vc-demo-source/hello-pi ~</code>## As root, change the permissions on the vchiq device so that all users can access it: <code>chmod a+rw /dev/vchiq</code># Select a demo. Change to that directory -- the directory name will be <code>~/hello_pi/''nameOfDemo''</code> -- for example, to change to the demo for the hello_audio program: <code>cd ~/hello_pi/hello_audio</code># Build the demo: <code>make</code># The resulting program name will end in <code>.bin</code> -- run it by typing: <code>./*.bin</code># You can modify the programs by editing the C source code (files ending in <code>.c</code>) and recompiling the software by typing <code>make</code> Note that in the See [[Raspberry Pi Fedora Remix, the vc (video core) libraries are in <code>/usr/lib</code> and subdirectories, and the headers are in <code>/usr/include</code>; utilities are in <code>/usr/bin</code> and <code>/usr/sbin</code>. This is different from the Foundation's reference image, which has these files in subdirectories of <code>/opt/vc</code>. The move from <code>/opt</code> to the system directories reflects the fact that these libraries are part of the base system and not a 3rd-party add-on. License information for the libraries is contained in the corresponding header filesMultimedia Demo Programs]].
