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These are some images from my research. Some have appeared in publications, and some have not.

Complex Shadows from Complex Lighting

The classic Stanford bunny has been placed in an environment map. These images demonstrate the limitations of approximating environment maps with point lights. The image on the left used 50 point light. The one on the right used 400. In Efficient Shadows from Sampled Environment Maps I showed how to calculate the right image at about the same cost as the left. However, notice that the shadows are still not smooth even with 400 lights. In my experiecnce, several thousand point lights are needed to do a good job at approximating an environment map when taking visibility (shadows) into account. These are a few more images created for Efficient Shadows from Sampled Environment Maps. I modeled the dominoes scene to create 'bars' of shadows which proved to be challenging form some permutations of the algorithm presented in the paper.

Complex BRDFs and Shadows in Complex Lighting

These images of the Earrings scene I created for Real-Time BRDF Editing in Complex Lighting show the dramatic affect material properties have on apperance. All three images where rendered using the same lighting environment, as evidenced by the reflection in the pearls. However, different edits to the cloth's material give widely varying moods for the scene. The phong exponent of the surfaces is increased from left to right, using the techniques described in Real-Time BRDF Editing in Complex Lighting. The most interesting feature of this ce is not the increase in 'shininess' of the surfaces, but the interplay of the BRDF with the shadows. Notice how the sphere's shadow becomes more prominent int eh second image, and then disappears. This type of effect proves that shadows are not a function only of the lighting, as the lighting is fixed throughout this sequence. These images appeared in Real-Time BRDF Editing in Complex Lighting. They demonstrate the range of appearance achievable by editing the objects' material properties.

Complex BRDFs in Simple Lighting

These images show some point-lit models edited according to the techniques described in Inverse Shade Trees. The top row demonstrates some standard material edits using the curve representation developed in that work. The bottom row shows some more exotic edits, and demonstrates the flexibility and utility of the curve-based BRDF representation.

Complex Effects in Complex Lighting

These image of a transparent, refracting vase (model courtesy of Ren Ng), show the importance of keeping the highest-frequency component of lighting when performing realighting on scenes. In Exploiting Temporal Coherence for Incremental All-Frequency Relighting, we showed how to achieve the (correct) result on the right at the same interactive frame-rates as the results on the left. A subtle point of that paper was to demonstrate that "All-frequency Relighting" has in the past been "Most-frequency Relighting". This work corrected that by ensuring the inclusion of even the highest frequencies.