ABSTRACT
Visualizing scalar data is frequently encountered in science, engineering, and medicine, but also in daily life. This chapter presents a number of the most popular scalar visualization techniques: color mapping, contouring, and height plots. Color mapping is probably the most widespread visualization method for scalar data. Putting it simply, color mapping associates a color with every scalar value. Colormap design is also influenced by application or domain-specific conventions and traditions. The vertex-based color mapping applies the color mapping at the vertices only, and then interpolates the mapped colors themselves. Texture-based color mapping produces reasonable results even for a sparsely sampled dataset. Typical scalar visualization applications would use between 64 and 256 different colors in a colormap, the preference being for more rather than fewer colors. Since a linear scalar-to-grayscale colormap was used, high-contrast borders between regions of different densities are easily seen.
