#CIS 565 : Final Project ##Position Based Fluids

Harmony Li, harmoli@seas.upenn.edu

Joseph Tong, josephto@seas.upenn.edu

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We want to implement a GPU based PBD fluid simulation stable enough to support large time steps for real-time applications. Through the enforcement of constant density positional constraints, the simulation will allow for incompressibility and convergence similar to smooth particle hydro-dynamic solvers. Our project will be largely based on Muller and Macklin’s paper “Position Based Fluids”.

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###Proposed Features:

• Meshless rendering (bilateral Gaussian or curvature flow)
• Caustics rendering for water?

###Implemented Features:

• Uses the density constraint to enforce incompressibility
• Artificial pressure term to simulate surface tension
• Vorticity confinement to replace energy
• Particle-based position based dynamics fluid simulator that runs on the GPU
• GPU Hash Grid for optimization of finding particle neighbors

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###Tentative Schedule

• Mon, 11/25 (Alpha)

• Setting up framework for constraint and particle system
• Set up visualization for particles

• Mon, 12/9 (Last day of class)

• begin writing paper
• Simulator with position based dynamics finished
• GPU hash grid

• Due date (Final)

• Meshless rendering finished
• Paper finished

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###Alpha Results

Slides

Notes

Video

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###Final Results

Slides

Video

Final Paper

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###Acknowledgments:

Many thanks to Mohammed Sakr(3dsakr@gmail.com), who has reached out with bug fixes and suggestions.

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###References: ####Fluid Simulation

• Position Based Fluids : M. Muller, M. Macklin
• Position Based Fluids : SIGGRAPH proceeding slides

####Rendering

• Screen Space Fluid Rendering with Curvature Flow : W. van der Laan, S. Green, M. Sainz
• [Reconstructing Surfaces of Particle-Based Fluids using Anisiotropic Kernels] (http://www.cc.gatech.edu/~turk/my_papers/sph_surfaces.pdf) : Yu, Turk