Aaron Lefohn

I am currently a Director of Research at NVIDIA. Before joining NVIDIA, I was the research lead for the Advanced Rendering Technology team at Intel, a real-time rendering and graphics programming systems research group. I joined Intel in 2007 when Intel acquired Neoptica, a computer graphics startup focused on creating heterogeneous rendering software for Sony PlayStation 3. Before joining Neoptica, I was a researcher and graphics software engineer at Pixar Animation Studios as well as a Ph.D. student in computer science in the graphics group at the University of California, Davis.

On this page, you'll also find the research path that has led me to my current pursuits. This past research includes real-time rendering, GPU programming models, interactive GPU-accelerated level-set segmentation , volume rendering, and macro- and micro- scale fluid simulations.

Ph.D. Dissertation

Glift: Generic Data Structures for Graphics Hardware
*2006 Best Doctoral Dissertation Award, UC Davis Computer Science Department*

Aaron E. Lefohn
September, 2006

Real-Time Rendering

Adaptive Image Space Shading for Motion and Defocus Blur
*Voted 3rd best paper at HPG 2012*

Karthik Vaidyanathan, Robert Toth, Marco Salvi, Aaron Lefohn
High Performance Graphics 2012 (HPG 12), pp. 13-21, June 2012

Adaptive Transparency
*Voted 2nd best paper at HPG 2011*

Marco Salvi, Jefferson Montgomery, Aaron Lefohn
High Performance Graphics 2011 (HPG 11), pp. 119-126, August 2011

Adaptive Volumetric Shadow Maps

Marco Salvi, Kiril Vidimce, Andrew Lauritzen, Aaron Lefohn
Computer Graphics Forum (proceedings of Eurographics Symposium on Rendering), 29(4), pp. 1289-1296, June 2010

Programmable Graphics--The Future of Interactive Rendering

Matt Pharr, Aaron Lefohn, Craig Kolb, Paul Lalonde, Tim Foley, Geoff Berry
Neoptica Technical Report, March 2007

Octree Textures on Graphics Hardware

J. Kniss, A. Lefohn, R. Strzodka, S. Sengupta, J. Owens
Technical Sketch at ACM SIGGRAPH 2005

* Note : Please also see Sylvain Lefebvre's excellent work on GPU Octree Textures (performed simultaneously with ours). Sylvain implemented a more traditional tree structure than we did, but we both came to the same conclusion that a shallow-branching solution is ideal on current hardware. The works are complimentary and I highly encourage you to look at his solution alongside ours.

Star-Ray Interactive Ray Tracing Demo

Software Developer
SGI Vendor Booth, ACM SIGGRAPH 2002

GPU Programming Abstractions
GPU-Accelerated Shading in Pixar's PhotoRealistic RenderMan

Announced at the Pixar RenderMan User's Group Meeting at ACM SIGGRAPH 2005

A Survey of General-Purpose Computation on Graphics Hardware

J. Owens, D. Luebke, N. Govindaraju, M. Harris, J. Kruger, A. E. Lefohn, and T. Purcell
Eurographics Computer Graphics Forum
, to appear, 2006

J. Owens, D. Luebke, N. Govindaraju, M. Harris, J. Kruger, A. E. Lefohn, and T. Purcell
State of the Art Report #2, Eurographics 2005

GPGPU: General-Purpose Computation on Graphics Hardware

M. Houston, I. Buck, N. Govindaraju, M. Harris, J. Henseley, J. Kruger, A. E. Lefohn, J. D. Owens
Course 24 at ACM SIGGRAPH 2007

Interactive Level-Set Segmentation

Interactive Deformation and Visualization of Level Set Surfaces Using Graphics Hardware
*Nominated for Best Paper Award*
*Proceedings Cover Image*

A. E. Lefohn, J. M. Kniss, C. D. Hansen, R. T. Whitaker
1: IEEE Visualization, pp. 75-82, 2003
2: University of Utah School of Computing Technical Report, UUCS-03-005, 2003

Volume Rendering

Deferred Filtering: Rendering from Difficult Data Formats

J. Kniss, A. E. Lefohn, N. Fout
Chapter 41 in GPU Gems II: Programming Techniques for High-Performance Graphics and General-Purpose Computation
Addison Wesley, pp. 669-677, 2005

Volume Rendering Techniques

M. Ikits, J. Kniss, A. E. Lefohn, C. Hansen
Chapter 39 in GPU Gems: Programming Techniques, Tips and Tricks for Real-Time Graphics
Addison Wesley, pp. 667-692, 2004

Gaussian Transfer Functions for Multi-field Volume Visualization

J. M. Kniss, S. Premoze, M. Ikits, A. E. Lefohn, C. D. Hansen, E. Praun
IEEE Visualization, pp. 497-504, 2003

Closed Form Solution to the Volume Rendering Integral with Gaussian Transfer Functions

J. Kniss, S. Premoze, M. Ikits, A. E. Lefohn, C. Hansen
University of Utah School of Computing Technical Report, UUCS-03-013, 2003

Physical Simulation

Particle-Based Simulation of Fluids

S. Premoze, T. Tasdizen, J. Bigler, A. E. Lefohn, R. T. Whitaker
Eurographics, Computer Graphics Forum, pp. 401-410, 2003

Polarflex: An MS-EVB Approach to a Polarizable and Flexible Water Model

A. E. Lefohn, M. Ovchinnikov, G. Voth
Poster at the West Coast Theoretical Chemistry Conference, Salt Lake City, UT, June, 2000

A Comparison of the Molecular Dynamics and the Instantaneous Normal Modes of a Solvated Diatomic Molecule

A. E. Lefohn, M. A. Leich, S. J. Schvaneveldt
Poster at the 213th American Chemical Society National Meeting, San Francisco, April 13-17, 1997