NDLI: Real-time soft shadows in dynamic scenes using spherical harmonic exponentiation

Content Provider	ACM Digital Library
Author	Ren, Zhong Zhou, Kun Sun, Bo Snyder, John Sloan, Peter-Pike Bao, Hujun Peng, Qunsheng Liu, Xinguo Guo, Baining Wang, Rui
Copyright Year	2006
Abstract	Previous methods for soft shadows numerically integrate over many light directions at each receiver point, testing blocker visibility in each direction. We introduce a method for real-time soft shadows in dynamic scenes illuminated by large, low-frequency light sources where such integration is impractical. Our method operates on vectors representing low-frequency visibility of blockers in the spherical harmonic basis. Blocking geometry is modeled as a set of spheres; relatively few spheres capture the low-frequency blocking effect of complicated geometry. At each receiver point, we compute the product of visibility vectors for these blocker spheres as seen from the point. Instead of computing an expensive SH product per blocker as in previous work, we perform inexpensive vector sums to accumulate the $\textit{log}$ of blocker visibility. SH exponentiation then yields the product visibility vector over all blockers. We show how the SH exponentiation required can be approximated accurately and efficiently for low-order SH, accelerating previous CPU-based methods by a factor of 10 or more, depending on blocker complexity, and allowing real-time GPU implementation.
Starting Page	977
Ending Page	986
Page Count	10
File Format	PDF
ISSN	07300301
e-ISSN	15577368
DOI	10.1145/1141911.1141982
Volume Number	25
Issue Number	3
Journal	ACM Transactions on Graphics (TOG)
Language	English
Publisher	Association for Computing Machinery (ACM)
Publisher Date	2006-07-01
Publisher Place	New York
Access Restriction	One Nation One Subscription (ONOS)
Subject Keyword	Volterra series Ambient occlusion Lighting environment
Content Type	Text
Resource Type	Article
Subject	Computer Graphics and Computer-Aided Design

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Real-time soft shadows in dynamic scenes using spherical harmonic exponentiation

Real-time soft shadows in dynamic scenes using spherical harmonic exponentiation

Real-time, all-frequency shadows in dynamic scenes

Dual space directional occlusion

Precomputed shadow fields for dynamic scenes

Supplement for real-time soft shadows in dynamic scenes using spherical harmonic exponentiation (2006)

Realtime soft shadows in dynamic scenes using spherical harmonic exponentiation (2006)

Volumetric Ambient Occlusion for Real-Time Rendering and Games

Real-Time Molecular Visualization Supporting Diffuse Interreflections and Ambient Occlusion

Real-time soft shadows in dynamic scenes using spherical harmonic exponentiation

Similar Documents

Real-time soft shadows in dynamic scenes using spherical harmonic exponentiation

Real-time soft shadows in dynamic scenes using spherical harmonic exponentiation

Real-time, all-frequency shadows in dynamic scenes

Dual space directional occlusion

Precomputed shadow fields for dynamic scenes

Supplement for real-time soft shadows in dynamic scenes using spherical harmonic exponentiation (2006)

Realtime soft shadows in dynamic scenes using spherical harmonic exponentiation (2006)

Volumetric Ambient Occlusion for Real-Time Rendering and Games

Real-Time Molecular Visualization Supporting Diffuse Interreflections and Ambient Occlusion

Real-time soft shadows in dynamic scenes using spherical harmonic exponentiation