Fast out-of-core isosurface extraction and rendering of time-varying data sets.

We present a combination of techniques for interactive out-of-core isosurface extraction and rendering of time-dependent datasets. We make use of an index tree that allows extraction of all isovalue-spanning cells from any timestep, and for any iso value, at rates of several hundreds of frames per second. This data structure is constructed in a pre-processing stage, and effectively uses the temporal coherence in the dataset. However, for very large datasets such as those resulting from CFD simulations, this tree structure can easily become too large to fit in main memory. Therefore, we have adapted the data structure for out-of-core application by adding an intelligent paging scheme, which allows interactive exploration of very large datasets on a normal PC. Only a user-specified time window will be kept in main memory and other parts of the tree will be read and released on-demand. This paging scheme was implemented using multi-threading. Finally, to avoid time- consuming triangulation and surface reconstruction, we have used a hardware-assisted direct point rendering algorithm, achieving interactive rendering framerates.

@InProceedings { VP05a,
  author       = "Vrolijk, Benjamin and Post, Frits H.",
  title        = "Fast out-of-core isosurface extraction and rendering of time-varying data sets.",
  booktitle    = "ASCI 2005 - Proceedings of the 11th annual conference of the Advanced School for Computing and Imaging",
  month        = "June",
  year         = "2005",
  editor       = "B.J.A. Kr{\"o}se and H.J. Bos and E.A. Hendriks and J.W.J. Heijnsdijk",
  note         = "90-803086-0-9",
  url          = "http://graphics.tudelft.nl/Publications-new/2005/VP05a"
}