Final answer:
Hatching and crosshatching are techniques that use diagonal lines to create different angles with a slight variance in length, commonly used to suggest volume and depth in drawing.
Step-by-step explanation:
The technique that uses diagonal lines to create angles by cutting the ends with a slight increase or decrease in length is known as hatching and crosshatching. These methods are commonly used in drawing to depict areas of shadow and to show volume on a flat surface. Such techniques are especially prevalent in media where line is the primary means of expression, such as in etching or black and white drawing. By varying the angle and density of the lines, an artist can convey depth, form, and the intensity of light and shadow across a subject.
Additionally, in the context of graphical representation, orthogonals are lines in linear perspective that converge at the vanishing point, implying the illusion of depth on a two-dimensional plane. The use of diagonals and perspective can significantly help in creating realistic images that appear to have three-dimensional form.