Proceedings: GI 2014

Micro-buffer rasterization reduction method for environment lighting using point-based rendering

Takahiro Harada

Proceedings of Graphics Interface 2014: Montréal, Québec, Canada, 7 - 9 May 2014, 95-102

  • BibTex

    author = {Harada, Takahiro},
    title = {Micro-buffer rasterization reduction method for environment lighting using point-based rendering},
    booktitle = {Proceedings of Graphics Interface 2014},
    series = {GI 2014},
    year = {2014},
    issn = {0713-5424},
    isbn = {978-1-4822-6003-8},
    location = {Montr{\'e}al, Qu{\'e}bec, Canada},
    pages = {95--102},
    numpages = {8},
    publisher = {Canadian Human-Computer Communications Society},
    address = {Toronto, Ontario, Canada},


This paper proposes a point-based rendering pipeline for indirect illumination for environment lighting. The method improves the efficiency of the algorithm used in the previous studies that calculate direct illumination on all the points in the scene which is prohibitively expensive for environment lighting because it requires a hemispherical integration for each point to compute direct illumination. The proposed rendering pipeline reduces the number of direct illumination computations by introducing approximations and careful selection of points on which indirect illumination is calculated. More specifically, the rendering pipeline first selects primary visible points on which indirect illumination is calculated from the point hierarchy. A micro-buffer is rasterized for each primary visible point to identify secondary visible points whose direct illumination affects indirect illumination of a primary visible point. Dependency of those points is analyzed and approximations are introduced to reduce the number of points on which micro-buffer rasterization is executed to calculate direct illumination. After direct illumination is obtained for those points, direct illumination on all of the primary and secondary visible points is calculated by illumination propagation without rasterizing any micro-buffer. The method can be used for a dynamic scene if it is combined with dynamic point hierarchy update.