building OpenSceneGraph

get the sources

• Download the OSG source from www.openscenegraph.org, or better a newer version from https://github.com/openscenegraph/osg/tree/OpenSceneGraph-3.2 that include fixes for the Visual Studio 2013 compiler.
• Get the Visual Studio 2013 dependencies (small package) from http://www.openscenegraph.org/index.php/download-section/dependencies (currently we need this for the osg jpeg plugin, you could also get the libjpeg from somewhere else).

build it

• Run CMake for OSG, set ACTUAL_3RDPARTY_DIR to the folder where you extracted the dependencies. You should set WIN32_USE_MP to 1 and OSG_USE_QT and all the BUILD_* to 0.
• Now build the osg core packages (elemate currently requires DB, GA, Terrain, Util and Viewer) and the jpeg, glsl and 3ds osg plugins.

setup environment

• For the elemate cmake, set the environment variables OSG_ROOT and OSG_DIR to the osg source and build folder, one each, so that our cmake scripts can find the sources and binaries there. Also add OSG_DIR/bin and the ACTUAL_3RDPARTY_DIR/bin to the Path variable. This way you only need to build the required osg packages. Furthermore it allows us to use the osg sources while debugging (step into it etc).