Crystal Glyph: Visualization of Directional Distributions Based on the Cube Map

Abstract

High resolution simulations are capable of generating very large vector fields that are expensive to store and analyze. In ad- dition, the velocity fields generated from some particle simulations are not stored on spatial grids, which become difficult to visualize using some traditional vector field visualization methods such as streamlines. Furthermore, the noise and/or uncer- tainty contained in the data often affects the quality of visualization by producing visual clutter that interferes with both the interpretation and identification of important features. An alternative approach is to store the distribution of many vector ori- entations and visualize the distribution with 3D glyphs. This paper presents the cube map histogram, a new data structure for storing the distribution of three-dimensional vector directions. We also present a glyph called the crystal glyph that effectively visualizes the directional distribution using OpenGL cube map textures. By placing crystal glyphs in the 3D data space, users can identify the directional distribution of the regional vector field from the shape and color of the glyph without visual clutter.