Real time rendering and animation of virtual characters

In this paper, we focus on the different aspects of real time visualization and animation of realistic virtual characters. The common goal for our research was to come up with solutions based on the concepts of the ISO standard X3D and if necessary propose generalized extensions to the standard. First we describe a high level control language and its implementation suitable for non-graphics experts. Then we focus on the different aspects of realistic rendering, how X3D must be extended to allow special effects and realization of novel rendering algorithms, including skin and emotion rendering. Next we explain the challenges of dynamics related to virtual characters covering play-back and blending of pre-defined animations, online simulation of locomotion and hair simulation. We will briefly introduce the issues related to creation of character geometries and animations as well as simple storytelling. All the work described in this paper was carried out in the project Virtual Human. During the past four years we made several observations for the graphics part of virtual characters, which can be found in a special section of this paper.