Multi-layered Framebuffer Condensation: The l-buffer Concept

  • Jarosław Konrad Lipowski
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6375)


In this paper we present a method that can be used with algorithms requiring the presence of multiple data elements at the last step of z-buffer based rasterization pipeline. The work presented here-in gives a ground for solutions to problems of order independent transparency; semi-transparent light occluders; non-uniform, light scattering media and visualization of voxel based data. It can also enable the interactive graphics researchers to adapt some algorithms previously only found in off-line solutions. Its general form also allows it to work seamlessly with hardware-accelerated multi-sampling techniques. The contributions of this work include:
  • general description of the data structures used in sparse to dense buffer condensation process;

  • mapping of the general structures into actual hardware resources;

  • rendering process for multi-layered sparse framebuffer;

  • condensing the sparse buffer into dense fragment list buffer;

  • mapping the list buffer into displayable framebuffer.


Interactive Graphic Geometric Primitive Sparse Attribute Fragment Count Composition Engine 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    OpenGL 4.0 Core Profile Specification (updated March 11, 2010),
  2. 2.
  3. 3.
    GL_ARB_multisample OpenGL extension specification,
  4. 4.
  5. 5.
    Everitt, C.: Interactive order-independent transparency. Tech. rep., NVIDIA Corporation (2001)Google Scholar
  6. 6.
    Eisemann, E., Coret, D.: Fast scene voxelization and applications. In: ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games, pp. 71–78 (2006)Google Scholar
  7. 7.
    Bavoil, L., Callahan, S.P., Lefohn, A., Comba, J.L.D., Silva, C.T.: Multi-Fragment Effects on the GPU using the k-Buffer. In: Proceedings of the 2007 symposium on Interactive 3D graphics and games, pp. 97–104 (2007)Google Scholar
  8. 8.
    Callahan, S.P., Ikits, M., Comba, J.L.D., Silva, C.T.: Hardwareassisted visibility sorting for unstructured volume rendering. IEEE Transactions on Visualization and Computer Graphics 11(3), 285–295 (2005)CrossRefGoogle Scholar
  9. 9.
    Carpenter, L.: The A-buffer, an antialiased hidden surface method. In: Computer Graphics (Proceedings of SIGGRAPH 1984), vol. 18, pp. 103–108 (1984)Google Scholar
  10. 10.
    Catmull, E.: A Subdivision Algorithm for Computer Display of Curved Surfaces. PhD thesis, Dept. of Computer Science, University of Utah (1974)Google Scholar
  11. 11.
    Wittenbrink, C.: R-buffer: A pointerless A-buffer hardware architecture. In: Graphics Hardware 2001, pp. 73–80 (2001)Google Scholar
  12. 12.
    OpenGL 2.1 Specification (December 1, 2006),
  13. 13.
    Myers, K., Bavoil, L.: Stencil Routed A-Buffer. In: ACM SIGGRAPH 2007: Sketches (2007)Google Scholar
  14. 14.
    GL_NV_explicit_multisample OpenGL extension specification,
  15. 15.
    GL_ARB_occlusion_query OpenGL extension specification,
  16. 16.
    GL_ARB_geometry_shader4 OpenGL extension specification,
  17. 17.
    GL_EXT_texture_array OpenGL extension specification,
  18. 18.
    GL_ARB_occlusion_query2 OpenGL extension specification,
  19. 19.
    GL_ARB_draw_buffers OpenGL extension specification,

Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Jarosław Konrad Lipowski
    • 1
  1. 1.Institute of Computer Science, Computer Graphics LaboratoryWarsaw University of TechnologyWarsawPoland

Personalised recommendations