A new rendering technique for water droplet using metaball in the gravitation force
Young-Jung Yu, Ho-Youl Jung, Hwan-Gue Cho · Digital Library (University of West Bohemia) · 1998
Till now there are many rendering models for water and other fluids and their dynamics. Especially in order to generate the curved surface of flexible objects such as water, jelly, and snow, the implicit metaball formulation is widely used in favor of its simplicity and flexibility. This paper proposes one novel method for generating water droplets, which would be deformed in a gravitation field. In previous works, a water droplet was simply represented by approximated curved surfaces of a symmetric and quite a simple metaball. So the finally rendered water droplet was far from a realistic droplet, because they did not consider the gravitation force in droplets attached on a surface. We give a new generalized metaball model for rendering water droplets placed on an arbitrary surface considering the gravitation and friction between droplets and the plate. Our new metaball model uses a new vector field isosurface function controlling the basic scalar metaball, with respect to the norm of gravitation force. In several experiments, we could render a photo-realistic water droplets with natural-looking shadows by applying ray-tracing techniques.