Generation of Shadows in Scene Graph based VR

In this paper, we present our experience implementing shadows in Scene Graph based Virtual Reality systems. Shadows are an important part of the human perception of both shape and depth and, yet, are a largely missing component in Virtual Environments. In this work, we investigate extending standard Scene Graphs to automatically produce shadowed scenes. This paper presents our experience embedding two popular real-time shadow methods, Shadow Mapping and Stencil Shadow Volumes, in a popular Scene Graph system, OpenGL Performer. Our experience has shown both ways in which they can be used and also a number of weakness in the current state of both Scene Graph systems and shadow methods. Based on our experiences, we present suggestions for the user desiring to include shadows in their Virtual Environment and highlight areas, where further development would benefit users significantly