Towards Animating Virtual Humans in Flooded Environments

The simulation of virtual humans organized in groups and crowds has been widely explored in the literature. Nevertheless, the simulation of virtual humans that interact with fluids is still incipient. Indeed it is easy to understand that human behavior is different from ordinary rigid bodies when affected by fluids, i.e., on the one hand, agents can try to walk, achieve their goals against fluid forces, trying to survive. On the other hand, humans can also be completely carried by the fluid, depending on the conditions, as a passive rigid body. A challenge in this area is that virtual agent simulation research often focuses on the realism of their trajectories and interaction with the environment, obstacles, and other agents, without considering that agents might evolve into an environment that can take control of their movements and trajectories in certain conditions. In this case, it is essential to note that, with proper integration between agents and fluids, we should be able to simulate agents who can continue walking despite an existing fluid (e.g., a weak fluid stream), walking with an effort to stay in the desired direction (e.g., medium stream), until they are partially or totally carried by a fluid, like a strong flow of water in a river or the sea. The main contribution of our model is to give the first step into simulating the steering behaviors of humans in environments with fluids. We integrate two published methodologies and available source codes in order to create our method. For the motion of virtual humans, we use BioCrowds; and SPlisHSPlasH as a fluid dynamics model. Results indicate that the proposed approach generates coherent behaviors regarding the influence of fluids on people in real events, even if this is not the objective of this paper, because other variables should be incorporated, in cases of serious simulations.

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