Research on Fast Soft Shadow Algorithm Based on 4D Rasterization

Zhao Qi; Wang Lili

doi:doi:10.11648/j.sd.20170501.17

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Research on Fast Soft Shadow Algorithm Based on 4D Rasterization

Zhao Qi, Wang Lili

Published in Science Discovery (Volume 5, Issue 1)

Received: 11 April 2017 Published: 12 April 2017

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Abstract

This paper introduces an algorithm that extends traditional 2D projection and rasterization to 4D space for fast soft shadow rendering. First, the rectangular area light source is seen as a point light source that translates with two degrees of freedom. As the point light source moving, the projections of the triangles and the output image samples on the projection plane are also moving. The locus of the projection is called the 4D projection. 4D projections are rasterized, and a conservative set of output image sample/triangle pairs can be obtained. The set is then examined to derive light mask for each sample. Since all potentially blocking triangles are considered, the algorithm is an accurate algorithm. And, the algorithm does not require any type of precomputation, so it supports fully dynamic scene. We have tested our algorithm on several scenes to render complex soft shadows accurately at interactive rates.

Published in	Science Discovery (Volume 5, Issue 1)
DOI	10.11648/j.sd.20170501.17
Page(s)	40-47
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2017. Published by Science Publishing Group

Keywords

Photorealistic Rendering, Soft Shadow, Three-Dimensional Graphics

References

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APA Style

Zhao Qi, Wang Lili. (2017). Research on Fast Soft Shadow Algorithm Based on 4D Rasterization. Science Discovery, 5(1), 40-47. https://doi.org/10.11648/j.sd.20170501.17

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ACS Style

Zhao Qi; Wang Lili. Research on Fast Soft Shadow Algorithm Based on 4D Rasterization. Sci. Discov. 2017, 5(1), 40-47. doi: 10.11648/j.sd.20170501.17

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AMA Style

Zhao Qi, Wang Lili. Research on Fast Soft Shadow Algorithm Based on 4D Rasterization. Sci Discov. 2017;5(1):40-47. doi: 10.11648/j.sd.20170501.17

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@article{10.11648/j.sd.20170501.17,
  author = {Zhao Qi and Wang Lili},
  title = {Research on Fast Soft Shadow Algorithm Based on 4D Rasterization},
  journal = {Science Discovery},
  volume = {5},
  number = {1},
  pages = {40-47},
  doi = {10.11648/j.sd.20170501.17},
  url = {https://doi.org/10.11648/j.sd.20170501.17},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.sd.20170501.17},
  abstract = {This paper introduces an algorithm that extends traditional 2D projection and rasterization to 4D space for fast soft shadow rendering. First, the rectangular area light source is seen as a point light source that translates with two degrees of freedom. As the point light source moving, the projections of the triangles and the output image samples on the projection plane are also moving. The locus of the projection is called the 4D projection. 4D projections are rasterized, and a conservative set of output image sample/triangle pairs can be obtained. The set is then examined to derive light mask for each sample. Since all potentially blocking triangles are considered, the algorithm is an accurate algorithm. And, the algorithm does not require any type of precomputation, so it supports fully dynamic scene. We have tested our algorithm on several scenes to render complex soft shadows accurately at interactive rates.},
 year = {2017}
}

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TY  - JOUR
T1  - Research on Fast Soft Shadow Algorithm Based on 4D Rasterization
AU  - Zhao Qi
AU  - Wang Lili
Y1  - 2017/04/12
PY  - 2017
N1  - https://doi.org/10.11648/j.sd.20170501.17
DO  - 10.11648/j.sd.20170501.17
T2  - Science Discovery
JF  - Science Discovery
JO  - Science Discovery
SP  - 40
EP  - 47
PB  - Science Publishing Group
SN  - 2331-0650
UR  - https://doi.org/10.11648/j.sd.20170501.17
AB  - This paper introduces an algorithm that extends traditional 2D projection and rasterization to 4D space for fast soft shadow rendering. First, the rectangular area light source is seen as a point light source that translates with two degrees of freedom. As the point light source moving, the projections of the triangles and the output image samples on the projection plane are also moving. The locus of the projection is called the 4D projection. 4D projections are rasterized, and a conservative set of output image sample/triangle pairs can be obtained. The set is then examined to derive light mask for each sample. Since all potentially blocking triangles are considered, the algorithm is an accurate algorithm. And, the algorithm does not require any type of precomputation, so it supports fully dynamic scene. We have tested our algorithm on several scenes to render complex soft shadows accurately at interactive rates.
VL  - 5
IS  - 1
ER  -

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Author Information

Zhao Qi

State Key Laboratory of Virtual Reality Technology and Systems, Bei Hang University, Beijing, China
Wang Lili

State Key Laboratory of Virtual Reality Technology and Systems, Bei Hang University, Beijing, China

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APA Style

Zhao Qi, Wang Lili. (2017). Research on Fast Soft Shadow Algorithm Based on 4D Rasterization. Science Discovery, 5(1), 40-47. https://doi.org/10.11648/j.sd.20170501.17

Copy | Download

ACS Style

Zhao Qi; Wang Lili. Research on Fast Soft Shadow Algorithm Based on 4D Rasterization. Sci. Discov. 2017, 5(1), 40-47. doi: 10.11648/j.sd.20170501.17

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AMA Style

Zhao Qi, Wang Lili. Research on Fast Soft Shadow Algorithm Based on 4D Rasterization. Sci Discov. 2017;5(1):40-47. doi: 10.11648/j.sd.20170501.17

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@article{10.11648/j.sd.20170501.17,
  author = {Zhao Qi and Wang Lili},
  title = {Research on Fast Soft Shadow Algorithm Based on 4D Rasterization},
  journal = {Science Discovery},
  volume = {5},
  number = {1},
  pages = {40-47},
  doi = {10.11648/j.sd.20170501.17},
  url = {https://doi.org/10.11648/j.sd.20170501.17},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.sd.20170501.17},
  abstract = {This paper introduces an algorithm that extends traditional 2D projection and rasterization to 4D space for fast soft shadow rendering. First, the rectangular area light source is seen as a point light source that translates with two degrees of freedom. As the point light source moving, the projections of the triangles and the output image samples on the projection plane are also moving. The locus of the projection is called the 4D projection. 4D projections are rasterized, and a conservative set of output image sample/triangle pairs can be obtained. The set is then examined to derive light mask for each sample. Since all potentially blocking triangles are considered, the algorithm is an accurate algorithm. And, the algorithm does not require any type of precomputation, so it supports fully dynamic scene. We have tested our algorithm on several scenes to render complex soft shadows accurately at interactive rates.},
 year = {2017}
}

Copy | Download

TY  - JOUR
T1  - Research on Fast Soft Shadow Algorithm Based on 4D Rasterization
AU  - Zhao Qi
AU  - Wang Lili
Y1  - 2017/04/12
PY  - 2017
N1  - https://doi.org/10.11648/j.sd.20170501.17
DO  - 10.11648/j.sd.20170501.17
T2  - Science Discovery
JF  - Science Discovery
JO  - Science Discovery
SP  - 40
EP  - 47
PB  - Science Publishing Group
SN  - 2331-0650
UR  - https://doi.org/10.11648/j.sd.20170501.17
AB  - This paper introduces an algorithm that extends traditional 2D projection and rasterization to 4D space for fast soft shadow rendering. First, the rectangular area light source is seen as a point light source that translates with two degrees of freedom. As the point light source moving, the projections of the triangles and the output image samples on the projection plane are also moving. The locus of the projection is called the 4D projection. 4D projections are rasterized, and a conservative set of output image sample/triangle pairs can be obtained. The set is then examined to derive light mask for each sample. Since all potentially blocking triangles are considered, the algorithm is an accurate algorithm. And, the algorithm does not require any type of precomputation, so it supports fully dynamic scene. We have tested our algorithm on several scenes to render complex soft shadows accurately at interactive rates.
VL  - 5
IS  - 1
ER  -

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