[osgviewer cow.osg] osgscribe.cow.osg
An example of how to decorate your scene graph geometry for useful effects such as scribing. This demo uses two instances of your model, the first one uses the state values set in your scene graph, the second instance override the polygmode to render it as wireframe, and with a polygon offset to ensure it is seen from all angles. These two instance are grouped together and then are treated like any other scene graph.