Research Report: Volume Rendering for Relational Data
Barry G. Becker · IEEE Symposium on Information Visualization · 1997
A method for efficiently volume rendering dense scatterplots of relational data is described. Plotting difficulties that arise from large numbers of data points, categorical variables, interaction with non-axis dimensions, and unknown values, are addressed by this method. The domain of the plot is voxelized using binning and then volume rendered. Since a table is used as the underlying data structure, no storage is wasted on regions with no data. The opacity of each voxel is a function of the number of data points in a corresponding bin. A voxel's color is derived by averaging the value of one of the variables for all the data points that fall in a bin. Other variables in the data may be mapped to external query sliders. A dragger object permits a user to select regions inside the volume.