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Research on Fast Soft Shadow Algorithm Based on 4D Rasterization

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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Cite This Article
  • 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
  • State Key Laboratory of Virtual Reality Technology and Systems, Bei Hang University, Beijing, China

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

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