This PhD position is granted by the VISITOR European project. Candidates should check their eligibility and apply according to the guidelines in: http://www.inrialpes.fr/movi/pub/Visitor/

Animated procedural textures for high-res fluids

Contact: Fabrice.Neyret@imag.fr
URL: http://www-evasion.imag.fr/Membres/Fabrice.Neyret/

keywords: image synthesis, fluids, turbulence, procedural textures, data amplification

Our long-term goal is the real-time animation of very detailed 3D fluids (e.g. avalanches, cascades, smoke, clouds, cloud fields...). Special effects for movies and video games use more and more fluids (water, steam, clouds, lava...). Still, the high-resolution CFD simulation they use is extremely costly (especially in 3D) and lets little control for the artist. Conversely, to “dress” surfaces with details artists often rely on textures, comprising procedural textures like Perlin noise (pseudo-random continuous fractal functions with controlled spectrum). We have developed preliminary models allowing us to define animated procedural textures (see biblio): flownoise which relies on rotative base functions, and advected textures which amplify a fluid simulation by adding small-scale flownoise which rotation spectrum is controlled using the Kolmogorov energy cascade.

As illustrated on the bottom images this topic is promising. Still, these preliminary models show us that several issues have to be studied and several fields have to be explored in order to settle a rock-solid general and pliable model: how to well-pose the continuous interpolation of grid-defined rotation fields, how to proceed to the non-linear combination of displacements at various scales in a procedural framework, how to interpret and adapt physical turbulence models such as the Kolmogorov vorticity spectrum in terms of useful parameters such as multiscale rotations, how to represent smartly fields of of procedural parameters as advected textures, how to advect efficiently these parameters in 3D (i.e. so that only opaque regions cost), how to adapt the representation, the advection process and the procedural rendering so to benefit from the high performances of programmable GPUs, etc... As one can see, there are avenues for interesting and ambitious researches in various fields so to get gorgious results !

Prerequisite: C/C++, OpenGL, Computer Graphics, interpolation, spectral analysis, notions on fluid physics

References:
[PN01] "Flow Noise". K. Perlin, F. Neyret. Siggraph'01 Technical Sketches and Applications. Los Angeles, août 2001.
[Ney03] "Advected Textures". F. Neyret. Symposium on Computer Animation'03. San Diego, juillet 2003.