The Use of Interactive Raster Graphics in the Display and Manipulation of Multidimensional Data

Techniques for the review, display, and manipulation of multidimensional data are developed and described. Multidimensional data is meant in this context to describe scalar data associated with a three dimensional geometry or otherwise too complex to be well represented by traditional graphs. Raster graphics techniques are used to display a shaded image of a three dimensional geometry. The use of color to represent scalar data associated with the geometries in shaded images is explored. Distinct hues are associated with discrete data ranges, thus emulating the traditional representation of data with isarithms, or lines of constant numerical value. Data ranges are alternatively associated with a continuous spectrum of hues to show subtler data trends. The application of raster graphics techniques to the display of bivariate functions is explored

Computer Graphics for Large Scale Two-and-Three-Dimensional Analysis of Complex Geometries

A comprehensive set of programs have been developed for analysis of complex two- and three- dimensional geometries. State of the art finite element and hydrodynamic codes are being used for the analytical portion of the work. Several additional codes depending heavily on graphics have been developed to assist the analytical effort. These are basically used for the pre- and post-processing of the data. Prior to running any analysis, the geometry of the body of interest must be represented in the form of small'finite elements.'After the analysis is run, the data must be post-processed. Both spatial and temporal data exist in the database. It is the database between the analysis codes and the post- processors which allows a wide variety of analysis codes to use the same post-processors. The temporal plotting codes produce time histories for specified quantities (i.e. temperature, pressure, velocity, stress, etc.) at various locations within the body. They may also produce cross-plots of these variables (i.e. stress vs. strain at a particular position). One of the two codes used for plotting of the spatial data is for two-dimensional geometries and the other for three-dimensional models. For three dimensions, the'Watkins'hidden surface / line processor is utilized for plots. The spatial plotters display contour lines on vector output devices and color fringes (or gray values) on raster output devices. They both may also display deformed geometries. Further the three-dimensional code has extensive animation capabilities for movie productions