1. Image Synthesis using Adjoint Photons

2. Motivation Participating Media Simplify Importance Sampling Support Wavelength Dependence

3. Participating Media

4. Ray Marching Result

5. Media as Probabilistic Entity

6. Probabilistic Media Example

7. Probabilistic Media Example 2

8. Rendering Comparison

9. Traversal Comparison

10. Software Impact Probabilistic media act like surfaces –Subclass them from Surface No volume pass after surface shading Separates intersection and shading

11. Shading Kernels Surfaces: Volumes:

12. Simplify Importance Sampling Remove Separation of Direct/Indirect Multiple Importance Sampling (MIS) Consistent Sampling Domain

13. Direct vs Indirect

14. Multiple Importance Sampling Impressive variance reduction Requires ability to request pdf arbitrarily Can lead to high branching

15. Mixture Densities Simplest combined sampling Similar performance to branched MIS

16. Tagged Objects

17. Wavelength Dependence Photons have individual wavelengths Scattering depends on wavelength Color Noise

19. Physical Sun and Sky

20. The Full System

21. Limitations

22. Acknowledgments State of Utah Center of Excellence NSF Grant 03-06151 Barry M. Goldwater Foundation