Hatching

The problem

Common shading algorithms in visualization system often relate only few information about local geometry — especially in regions that only have smooth, shallow transitions.

This deficiency does not show up to the observer in interactive systems that deliver a high framerate, as the human eye can derive the required information from motion parallax and the movement patterns of specular highlights. The observer will move interesting structures to the image center, pivot around them and thus allow the eye to gather the required information.

This information is not available in still images, which are used a lot for documentation purposes like printouts, webpages, etc.

A possible solution: Hatch textures

Hatch textures in ECCET

ECCET had available rendering modalities that provide very similar effects for several years. The following table shows how hatching effects enhance the visualization of local geometry.

Overview images: small big

	Gradient	GaussInt	GaussReg
0
1
2