Haber, Robert B. & McNabb, David A.

Visualization Idioms:
A Conceptual Model for Scientific Visualization Systems

This text is partially taken from [HAB90]

Haber & McNabb described a conceptual visualization process in three major transformations. These transformations occur in most visualization processes, and convert raw simulation data into a displayable image. The goal of these transformations on the data, is to convert the information (e.g. gained from a simulation) to a format amenable to understanding by the human perceptual system while maintaining the integrity of the information.

  1. The first transformation is described as data enrichment or data enhancement. It operates on the raw data which was gained by a simulation for example. The raw data is modified into derived data for subsequent visualization operations.
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  3. The next transformation is the visualization mapping. It constructs an imaginary object called "abstract visualization object" (AVO) from the derived data produced by data enrichment and data enhancement. An AVO is an imaginary object with extensions in space and time. The AVO consists of an attribute field, in which the (simulation) data is mapped. These attribute fields might include geometry, time, color, transparency, luminosity, reflectance, and surface texture. To accomplish the mapping between the (simulation) data and the AVO attribute fields there exists some transfer functions, which define some simple mappings between them. The transfer functions can vary widely in complexity.
    No fool-proof method exists to derive effective transfer functions. Therefore interactive systems for real-time modification of the transfer functions are effective tools for exploring computational data sets.[see reference 1 below]

    The Figure shows the conceptual diagram of visualization.

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  5. The last transformation is the rendering phase. Rendering operates on the AVO to produce at least one displayable image. The typical rendering operations would include view transformations (like rotation, translation, scaling, perspective mapping, and clipping) and optical models (such like hidden surface removal, shading, shadowing, anti-aliasing, and so forth). Some newer operations deal with volume rendering, which is an important development for visualizing three-dimensional systems. [see References 2 through 4 below]
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Other systems that use this idiom: Ignatius' & Senay's VISTA


References:

  1. D.Cox, "Using the Supercomputer to Visualize Higher-Dimensions: An Artist`s Contribution to Scientific Visualization." Leonardo, Vol.22, 1988, pp. 233-242.
  2. R.Drebin, L.Carpenter, and P.Hanrahan, "Volume Rendering", ACM Computer Graphics, Vol.22, August 1988, pp. 65-74.
  3. M.Levoy, "Display of Surfaces from Volume Data", IEEE Computer Graphics and Applications, Vol.8, May 1988, pp. 29-37.
  4. C.Upson and M.Keeler, "V-BUFFER: Visible Volume Rendering", ACM Computer Graphics, Vol.22, 1988, pp. 59-64.

Visualization Concepts

Last modified on March 29, 1999, G. Scott Owen, owen@siggraph.org