Section: Research Program

Computer animation

Computer animation is the branch of computer science devoted to models for the representation and simulation of the dynamic evolution of virtual environments. A first focus is the animation of virtual characters (behavior and motion). Through a deeper understanding of interactions using VR and through better perceptive, biomechanical and motion control models to simulate the evolution of dynamic systems, the Mimetic team has the ability to build more realistic, efficient and believable animations. Perceptual study also enables us to focus computation time on relevant information (i.e. leading to ensure natural motion from the perceptual points of view) and save time for unperceived details. The underlying challenges are (i) the computational efficiency of the system which needs to run in real-time in many situations, (ii) the capacity of the system to generalise/adapt to new situations for which data was not available or for which models were not defined for, and (iii) the variability of the models, i.e. their ability to handle many body morphologies and generate variations in motions that would be specific to each virtual character.

In many cases, however, these challenges cannot be addressed in isolation. Typically character behaviors also depend on the nature and the topology of the environment they are surrounded by. In essence, a character animation system should also rely on smarter representations of the environments, in order to better perceive the environment, and take contextualised decisions. Hence the animation of virtual characters in our context often requires to be coupled with models to represent the environment, reason, and plan both at a geometric level (can the character reach this location), and at a semantic level (should it use the sidewalk, the stairs, or the road). This represents the second focus. Underlying challenges are the ability to offer a compact, yet precise representation on which efficient path and motion planning can be performed, and on which high-level reasonning can be achieved.

Finally, a third scientific focus tied to the computer animation axis is digital storytelling. Evolved representations of motions and environments enable realistic animations. It is yet equally important to question how these event should be portrayed, when and under which angle. In essence, this means integrating discourse models into story models, the story representing the sequence of events which occur in a virtual environment, and the discourse representing how this story should be displayed (ie which events to show in which order and with which viewpoint). Underlying challenges are pertained to (i) narrative discourse representations, (ii) projections of the discourse into the geometry, planning camera trajectories and planning cuts between the viewpoints and (iii) means to interactively control the unfolding of the discourse.

By therefore establishing the foundations to build bridges between the high-level narrative structures, the semantic/geometric planning of motions and events, and low-level character animations, the Mimetic team adopts a principled and all-inclusive approach to the animation of virtual characters.