Proceedings: GI 2010

Two-level ray tracing with reordering for highly complex scenes

Johannes Hanika, Alexander Keller, Hendrik Lensch

Proceedings of Graphics Interface 2010: Ottawa, Ontario, Canada, 31 May - 2 June 2010, 145-152

  • BibTex

    author = {Hanika, Johannes and Keller, Alexander and Lensch, Hendrik},
    title = {Two-level ray tracing with reordering for highly complex scenes},
    booktitle = {Proceedings of Graphics Interface 2010},
    series = {GI 2010},
    year = {2010},
    issn = {0713-5424},
    isbn = {978-1-56881-712-5},
    location = {Ottawa, Ontario, Canada},
    pages = {145--152},
    numpages = {8},
    publisher = {Canadian Human-Computer Communications Society},
    address = {Toronto, Ontario, Canada},


We introduce a ray tracing scheme, which is able to handle highly complex geometry modeled by the classic approach of surface patches tessellated to micro-polygons, where the number of micropolygons can exceed the available memory. Two techniques allow us to carry out global illumination computations in such scenes and to trace the resulting incoherent sets of rays efficiently. For one, we rely on a bottom-up technique for building the bounding volume hierarchy (BVH) over tessellated patches in time linear in the number of micro-polygons. Second, we present a highly parallel two-stage ray tracing algorithm, which minimizes the number of tessellation steps by reordering rays. The technique can accelerate rendering scenes that would result in billions of micro-polygons and efficiently handles complex shading operations.