Robert Bridson Assistant professor in the Imager and SCL labs, UBC Computer Science Ph.D. Stanford '03, MMATH Waterloo '99, BMATH Waterloo '98 email rbridson @ cs.ubc.ca phone   604-822-1993 office   ICICS/CS X663 mail Dept. Computer Science, UBC 201-2366 Main Mall Vancouver, V6T 1Z4, Canada

Current Industry Work

Most recently I have cofounded Exotic Matter, a graphics company making physical simulation software for the film industry.

Since getting started with cloth simulation code used for Star Wars: Episode II - Attack of the Clones and many subsequent Industrial Light and Magic films, I have helped out a number of visual effects studios on physics-based animation. I co-wrote the Squirt fluid simulator for Double Negative Visual Effects, seen in many films including Harry Potter and the Half-Blood Prince (water, smoke, fire, clouds and more), 2012 (fire etc.), Inkheart (the Shadow, a smoke creature, for which I got a screen credit), Quantum of Solace (smoke and fire), The Dark Knight (smoke simulation) and Hell Boy II: The Golden Army (fire, slime, and vapour simulation).

Animations and Images

Books

Fluid Simulation for Computer Graphics, R. Bridson, A K Peters, 2008. My website for the book is at: www.cs.ubc.ca/~rbridson/fluidbook.

Refereed Publications

• SpikeNav: using stylus tilt in three-dimensional navigation, R. Bridson, ACM UIST 2009, poster session.
• Animating smoke as a surface, T. Brochu and R. Bridson, Symposium on Computer Animation 2009, poster session. (movie)
• Robust topological operations for dynamic explicit surfaces, T. Brochu and R. Bridson, accepted in SIAM Journal on Scientific Computing 2009. (for related software, see the El Topo project page.)
• Evolving sub-grid turbulence for smoke animation, H. Schechter and R. Bridson, Symposium on Computer Animation 2008. (full movie)
• Accurate viscous free surfaces for buckling, coiling, and rotating liquids, C. Batty and R. Bridson, Symposium on Computer Animation 2008. (movie, project page)
• Animating developable surfaces using nonconforming elements, E. English and R. Bridson, Proc. ACM SIGGRAPH 2008. (movie)
• Fast Poisson disk sampling in arbitrary dimensions, R. Bridson, ACM SIGGRAPH 2007 Sketches Program. (download the curl-noise example code for a public-domain implementation).
• A fast variational framework for accurate solid-fluid coupling, C. Batty, F. Bertails, and R. Bridson, Proc. ACM SIGGRAPH 2007. (movie, project page)
• Curl noise for procedural fluid flow, R. Bridson, J. Hourihan, and M. Nordenstam, Proc. ACM SIGGRAPH 2007. (movie and public domain example code available.) See also Ivan DeWolf's technical report Divergence-free noise for a slightly different approach.
• Fluid animation with explicit surface meshes, T. Brochu and R. Bridson, Symposium on Computer Animation 2006, poster session.
• Cloth animation through unbiased strain limiting and physics-aware subdivision, D. Tsiknis and R. Bridson, Symposium on Computer Animation 2006, poster session.
• A multi-preconditioned conjugate gradient algorithm, R. Bridson and Chen Greif, SIAM Journal on Matrix Analysis and Applications, 2005, vol. 27, no. 4, pp. 1056-1068.
• Animating sand as a fluid, Y. Zhu and R. Bridson, ACM SIGGRAPH 2005. (see below for code)
• Adaptive physics based tetrahedral mesh generation using level sets, R. Bridson, J. Teran, N. Molino and R. Fedkiw, Engineering with Computers 2005.
• Nonconvex rigid bodies with stacking, E. Guendelman, R. Bridson, and R. Fedkiw, ACM Transaction on Graphics, vol. 22, no. 3, Proc. ACM SIGGRAPH 2003, pp. 871-878.
• Simulation of clothing with folds and wrinkles, R. Bridson, S. Marino, and R. Fedkiw, Proc. ACM/Eurographics Symposium on Computer Animation 2003, pp. 28-36.
• A crystalline, red green strategy for meshing highly deformable objects with tetrahedra, N. Molino, R. Bridson, J. Teran, and R. Fedkiw, Proc. International Meshing Roundtable 2003.
• Robust treatment of collisions, contact and friction for cloth animation, R. Bridson, R. Fedkiw and J. Anderson, ACM Transactions on Graphics, vol. 21, no. 3, Proc. ACM SIGGRAPH 2002, pp. 594-603.
• Multiresolution approximate inverse preconditioners, R. Bridson and W.-P. Tang, SIAM Journal on Scientific Computing, vol. 23, no. 2, pp. 463-479.
• A structural diagnosis of some IC orderings, R. Bridson and W.-P. Tang, SIAM Journal on Scientific Computing, vol. 22, no. 5, pp. 1527-1532
• Refining an approximate inverse, R. Bridson and W.-P. Tang, Journal on Computational and Applied Math, 123 (2000), Numerical Analysis 2000 vol. III: Linear Algebra, pp. 293-306.
• Ordering, anisotropy and factored approximate inverses, R. Bridson and W.-P. Tang, SIAM Journal on Scientific Computing, vol. 21, no. 3, pp. 867-882.
• The asymptotic regimes of tilted Bianchi II cosmologies, C. G. Hewitt, R. Bridson, and J. Wainwright, General Relativity and Gravitation, vol. 33, no. 1, pp. 65-94.

Other Publications

• Fluid Simulation, SIGGRAPH 2006 and 2007 courses.
• Cloth collisions, SIGGRAPH 2005 course slides (w/o movies).
• Computational aspects of dynamic surfaces, my PhD thesis, supervised by Ron Fedkiw, Stanford University, 2003.
• Multiresolution approximate inverses, my Masters thesis, supervised by Wei-Pai Tang. University of Waterloo, 1999.
• Ordering for Factored Approximate Inverse Preconditioners, with Wei-Pai Tang. This is an extended abstract for the 1998 Copper Mountain Conference on Iterative Methods.

My Group

Note: if you are interested in becoming a graduate student at UBC, check out our prospective graduate students page. You will have to apply to the department/university, not to me directly.

Current:

• Christopher Batty (PhD - NSERC)
• Hagit Schechter (PhD - BC Industrial Innovation Scholarship)
• Tyson Brochu (PhD - NSERC)
• Mark Wiebe (MSc - NSERC Julie Payette)
• Zheng Wang (MSc)
• Sean Sutherland (MSc)
• Landon Boyd (MSc - NSERC)
• Essex Edwards (MSc - NSERC)
• Ives Macêdo (PhD - visiting)
• Farbod Roosta-Khorasani (BSc - UGRA)

Past:

• Florence Bertails (Postdoc)
• Michael Bonner (MSc). Thesis: Compressible subsonic flow on a staggered grid
• Tyson Brochu (MSc - NSERC). Thesis: Fluid animation with explicit surface meshes and boundary-only dynamics
• Richard Corbett (MSc - UGF). Thesis: Point-based level sets and progress towards unorganized particle based fluids
• Elliot English (BSc). Thesis: Animating Developable Surfaces using Nonconforming Elements
• Fraser Pogue (undergrad directed studies)
• Dinos Tsiknis (MSc - NSERC, UGRA). Thesis: Better cloth through unbiased strain limiting and physics-aware subdivision
• David White (MSc). Thesis: Keyframe Animation of Implicit Models
• Brent Williams (MSc). Thesis: Fluid surface reconstruction from particles
• Albert Wong (MSc - NSERC). Essay: The moving contact line in a shallow water model
• Alan Woo (MSc - UGF). Thesis: Realistic smoke simulation using a frustum aligned grid
• David Young (MSc - NSERC). Thesis: Controllable, non-oscillatory damping for deformable objects
• Yongning Zhu (MSc). Thesis: Animating sand as a fluid

Downloads

All files in this section are in the public domain unless otherwise indicated.

Many of my or my group's projects use a variety of files from a "common" directory: not exactly a proper library, but a collection of occasionally very useful files for C++ hacking. Some of the more stable members are available in the public domain here:

• common_2008_nov_12.tar.gz

Here are some more specific projects, organized by topic:

• Linear Algebra and Optimization
• maxmin1.tar.gz, a very simple program for solving tiny linear max-min problems (a variant of simplex for LP).
• Quern, a sparse QR library for direct and iterative solvers.
• KKTDirect, a direct solver package for saddle-point matrices.
• MPCG, MATLAB source for the multi-preconditioned conjugate gradient algorithm.
• ainvInC.tar.bz2, a C implementation of "matrix-free" SAINV, a factored approximate inverse preconditioner which doesn't require a matrix, only a linear operator.
• sainvmex.tar.bz2, a CMEX version of SAINV, callable from MATLAB (but with the speed of admittedly unoptimized C)
• etree_balance.m, a MATLAB m-file for postordering a symmetric-structure sparse matrix to give a balanced (minimum height) elimination tree.
• etree_unbalance.m, a MATLAB m-file for postordering a symmetric-structure sparse matrix to give an unbalanced elimination tree.
• imatrix.m, a MATLAB m-file for converting a matrix into an I-matrix (all entries bounded by 1 in magnitude and with unit diagonal).
• metismex.c, a MATLAB CMEX interface to the Metis graph partitioning and matrix ordering library. (Note: somewhat out of date - probably won't compile with newer versions of Metis)
• Geometry
• Tunicate, a library of robust computational geometry predicates in floating point.
• El Topo, a robust surface tracking library that maintains an untangled high quality triangle mesh even in the face of topological changes.
• Graphics
• SpikeNav example 3D navigation user interface.
• curl-noise example code (also includes fast Poisson disk sampling in arbitrary dimensions).
• simple_flip2d.tar.gz, old code for a simple PIC/FLIP 2d water simulation.
• gridimplicit.cpp, a shape plug-in for the pbrt ray-tracer, providing implicit surfaces sampled on a grid.
• sculpt.tar.bz2, a C++ simple sculpting program based on level sets, multi-resolution point splatting, etc. See my PhD thesis for a write-up on it.
• Miscellaneous
• DumpPDFAnnotations.zip: a command-line application for Mac OS X to dump the annotations contained in a PDF file.
• infix.c: a really simple example of parsing infix expressions (no parentheses or functions, just basic calculator functionality)

Teaching

Current courses:

• CPSC 314, Computer Graphics, September-December 2009
• CPSC 542G, Scientific Computing (Graduate Breadth), September-December 2009

I have taught in the past:

• CPSC 548, Directed Studies (physics-based animation)
• CPSC 314, Computer Graphics, September-December 2008
• CPSC 542G, Scientific Computing (Graduate Breadth), September-December 2008
• CPSC 426, Computer Animation, January-May 2008
• CPSC 542G, Scientific Computing (Graduate Breadth), September-December 2007
• CPSC 542G Scientific Computing (Graduate Breadth), September-December 2006
• CPSC 533D Animation Physics, September-Decemeber 2005
• CPSC 426 Computer Animation, September-December 2005
• CPSC 533D Animation Physics, January-April 2005
• CPSC 426 Computer Animation, September-December 2004
• CPSC 533B Animation Physics, January-April 2004

Personal

Here's some music I've written (more to come as I typeset it):

• prelude in d minor
• aishet chayil

I also wrote a little duet part for the Bach "Minuet No. 3" in Suzuki Viola Book One: minuet3.pdf (and MIDI output from LilyPond too).

A little poem: Comfort.

A few tracks I recorded: Recovery, Marked.

My son's first movie is Atlantic Ocean (I got to have a supporting role, and served as technical consultant :-)).

Some other short animations, from a traditional animation class with Lorie Loeb:

• Door Play
• Surfacing (listen to this with Otis Redding's "Sittin' on the Dock of the Bay" playing)

Here's source code for a simple 2D fluid simulator I wrote for a course project once.

I did a hectic project involving digital sculpting, environment map acquisition from uncalibrated photos, fast ray-tracing of micro-facet textured level sets, and compositing (producing images like this) for the Stanford cs348b rendering competition.

Here's source code for a 3D first-person video-game, Spaceman Spiff: Escape from Zorg, which I wrote for the Stanford cs248 video game competition.

A word-for-word translation I made of the sung parts of the Latin mass: mass.pdf.

Aliens apparently invaded my left ear.

And like the book says, we might be through with the past, but the past, it ain't through with us.