Highlight

Surface illumination is performed using the Command Highlight in different ways: By Angle, By Sin and By Tang. As a fact, during this operation the new color of the point is now defined not by its height, but the angle of surface inclination (by Angle), sinus of this angle (by Sin), or by tangents of this angle (by Tang). Such operations are called as gradient transformations. The button corresponds to the option by Angle.