关键词: 图学, 投影理论, 焦点透视, 散点透视

Abstract: Demonstrating the approach to protract the figure of three-dimensional graphs
with geometrical forms in two-dimensional planes, graphics is a basic technical discipline of
examining protracting engineering drawings using the method of projection and addressing issues
on space geometry as well as its theory and approach. Graphics is also a kind of semiotic system
of writing. China boasts of rich tradition of graphics with amazing architectural drawings in
Pre-Qin period, booming theories of graphics in Wei and Jin dynasties, refined protracted
drawings in Song and Yuan dynasties, and graphics being regarded as important instruments in
Ming and Qing dynasties when thorough apprehension were pursued in order to seek the practice
of administration. It not only forms the basis for modern and contemporary graphics in China, but
also shapes the future development of graphics. The projection theory of Chinese graphics not
only provides information support for technical development, but also lays out theoretical
foundation of rapid modernization of Chinese graphics.

Key words: graphics, projection theory, focus perspective, cavalier perspective