In estimating designed architectural buildings, many factors in various design domains such as function, structure, form, environment may be considered and then a building design might be selected or modified as final design from many possible design results. This paper proposed a method to obtain complexity values from two dimensional drawings which are floor plans or elevations. The Complexity values could be turned into esthetic values. The method has been developed based on information theory, shape pattern representation and cognitive theory. Results of measuring complexity value can make the computer evaluate and select final results produced from automatic design processes by the computer That is to say, aesthetic values based on order and chaos can be measured using complexity values and then some results having superior values can be selected as final result. Also some cognitive processes as perception of two dimensional drawings are discussed using shape representations. Aesthetic values could be varied in terms of shape properties such as size, individualities and knowledge as well as order and chaos.