The Use of Straight Lines in Composition
Artists use straight lines in the early design stages of creating art more often than curves because you can formalize, measure, and relate a straight line easier than you can a curved line. Using straight lines also allows the artist to place all their composition elements in a design grid accurately. In the images below, notice how John Singer Sargent uses straight lines to formalize all of his drawings. Straight lines give a work of art visual power. Formalize means that an artist will refine, exaggerate, modify, alter, and order what they are looking at; in other words, they aren't copying what they see.
Drawing above by Vincent van Gogh demonstrating the use of straight lines.
Drawing above by a former student of Myron Barnstone demonstrating the use of straight lines.
Self Portrait by Claudia Rilling, a former student of Myron Barnstone.