A central problem in drawing is how to represent aspects of three-dimensional reality on a surface that has only two dimensions. In the course of human history, various empirical methods evolved to represent the depth of space and objects within it. Manifestations of what we now call orthographic projection occur on Egyptian temple walls and in Greek vase paintings. There are numerous examples of oblique projection in Indian, Chinese, and Japanese art. We even find instances of linear perspective in Roman murals.
Today, these visual systems of representation constitute a formal language of design drawing governed by a consistent set of theories, principles, and conventions. We categorize these modes of representation into distinct types of drawing systems. We refer to these as systems to distinguish them from drawing techniques, which pertain to how we make marks on a sheet of paper or a computer screen.
In design, drawing systems provide alternative ways of thinking about and representing what we see before us or envision in the mind’s eye. Each drawing system involves a built-in set of mental operations that directs our exploration of a design problem. In selecting one drawing system over another to convey visual information, we make conscious as well as unconscious choices as to which aspects of our perception or imagination can or should be expressed. The choice of a drawing system is as much a question of what to conceal as it is a decision about what to reveal.
