A Directional Occlusion Shading Model for Interactive Direct Volume Rendering.

Mathias Schott Vincent Pegoraro Charles D. Hansen Kevin Boulanger Kadi Bouatouch A Directional Occlusion Shading Model for Interactive Direct Volume Rendering. 855-862 2009 28 Comput. Graph. Forum 3 http://dx.doi.org/10.1111/j.1467-8659.2009.01464.x db/journals/cgf/cgf28.html#SchottPHBB09