Real-time Ray-tracing Real-time Ray-tracing Programmable
Graphics Hardware Programmable Graphics Hardware Precomputed
Radiance Transfer Precomputed Radiance Transfer Wang et al.
SIGGRAPH 09Dachsbacher et al. SIGGRAPH 07 6 Ritschel et al.
SIGGRAPH Asia 08
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02 03 04 05 Sloan et al. SIGGRAPH 02 Ng et al. SIGGRAPH 03
Sloan et al. SIGGRAPH 03 Ng et al. SIGGRAPH 04 Wang et al. EGSR 04
Lui et al. EGSR 04 Sloan et al. SIGGRAPH 05 Zhou et al. SIGGRAPH 05
8 Pioneer, SH CPCA Wavelet Triple Product In-Out Fac. In-Out Fac.
Dynamic Scenes Dynamic Scenes
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07 08 09 Wang et al. ACMTOG 06 Green et al. I3D 06 Green et al.
EGSR 07 Sun et al. SIGGRAPH 07 Ben-Artzi et al. ACMTOG 08
Ramamoorthi CG&V 09 Wang et al. SIGGRAPH Asia 09 9 06 Xu et al.
TVCG 08 Ben-Artzi et al. SIGGRAPH 06 Tsai et al. SIGGRAPH 06 SRBF
BRDF-Editing CTA SVBRDF, BRDF-Editing Survey BRDF-Editing With G.I.
BRDF-Editing With G.I. BRDF-Editing With G.I. BRDF-Editing With
G.I.
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11 Fit clamped cosine term to basis Wang et al. SIGGRAPH Asia
09 supplement materials
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12 lobe axis lobe sharpness lobe amplitude
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13 Rotated version Single Lobe Two LobesMultiple Lobes
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Decoupling BRDF from visibility 6D SVBRDF Represent 4D NDF
(Microfacet) Visibility (binary) SSDF (Spherical Signed Distance
Functions) Fit into SGs Map PCA Mixture of SGs (Spherical
Gaussians) 18 Eigen- Vectors Eigen- Vectors
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20 Fresnel Term Geometry Term Normal Distribution Function
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remaining factor (shadowing+Fresnel) NDF Very Smooth
High-Frequency Fit into SGs 21
ground truth 7-lobe SG (this paper) 256-term 64-term BRDF
factorization Ashikhmin-Shirley n u =8,n v =128 Ashikhmin-Shirley n
u =25,n v =400 Ashikhmin-Shirley n u =75,n v =1200 23
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fabric green delrinsteel phenolic yellow albm bronze violet
acrylic ground truth 1SG 2SG 3SG 256-Term Fac. 64-Term Fac. 27
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32 Reconstructed Visibility : elevation angle Inner product /
vector product of SGs and V(i) can be efficiently evaluated in the
run time!
40 Cosine Approximation Lighting Approximation BRDF
Approximation Visibility Approximation SGs for NDF Spherical
WarpMultiplied remaining factor PCA coefficients of SSDFs
Uncompressed on GPU
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Per-vertex vs. per-pixel wireframe per-vertex shadingper-pixel
shading 43
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Distant environmental light + nearby point light 44
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Results for isotropic BRDFs 45
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Results for anisotropic BRDFs 46
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Video 47
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51 Transfer vector (diffuse) Transfer Matrix (glossy)
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53 = LoLo LiLi Column: Lighting direction Row: Pixel or
Vertex
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Factor the BRDF into terms which depend only on incident /
outgoing angles We can then define and precompute a view-
independent transport function Thus, rendering is reduced to
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