The architectural design is a concrete and complete example of the general notions that we have mentioned. Having to respond to more or less precise initial constraints, architectural problems are poorly defined problems. From then on, the architect is part of a creative design process, manipulating broad knowledge from transversal fields, both in technical fields (many and various building techniques) as well as artistic, historical or socio-cultural.
THE ARCHITECTURAL DESIGN
According to Jean-Charles L EBAHAR, [ Lebahar1983 ], the architectural design reveals three main phases:
THE ARCHITECTURAL DIAGNOSIS.
It is in this phase of solving the problem that the architect will identify and define it in accordance with the basic constraints. It will then take into account the financial constraints of the client, the surface and topology of the land, the ecological and legal constraints, the rules of compliance. To do this, he will visit the premises, discuss with his client but also use documents related to these data: photographs, survey plans, etc. Combining everything with his own knowledge and knowledge, he is then in an exploration phase, the result of which will be a first “graphic simulation base”, a mixture of notes and initial drawings.
THE SEARCH FOR THE OBJECT BY GRAPHIC SIMULATION.
From then on, the designer will begin what we called the generation of solutions and their evaluation, in an incremental and iterative process. And it is the drawing that will be the privileged vector of this approach. He will support the simulation, based on the successive transformations that will develop the reasoning of the architect, until a precise definition of acceptable solutions to the problem. In this situation, as we have already mentioned when talking about the conversation between the designer and his drawing, the drawing is more than a support. It represents, as Jean-Charles L EBAHAR underlines, “the object in creation and the thought that creates it”.
ESTABLISHMENT OF THE CONSTRUCTION MODEL.
This phase is the establishment of precise graphic representations, intended to make the solution clear for the manufacturers. It is the “final decision concerning the whole project”(plans, precise and meter drawings, with a specified scale, etc.).You don’t have to go further into the details of architectural design to see that drawing holds a dominant place in this process, and in all its stages. Of course, the architect also uses other visual representations.He uses various documents in the first phases of analysis, but these are only contributions to his construction of the problem, not vectors of its resolution. In the same way, he can build physical or virtual models of his project, but this already presupposes a successful solution to the problem. It will be used for the presentation of the project, for its communication. To a lesser extent, they will allow an additional evaluation of the solution which may lead to refinements, but they will not constitute creative support like the
THE ARCHITECTURAL DRAWING
To identify the types of architectural drawing and their functions in the hard of an architectural project, we take in this section three functions adopted by Daniel E Steve: the speculative drawing, descriptive drawing, and prescriptive drawing [ Estevez2001 ], which specializes those of Eugene FERGUSON that we had already mentioned in the general context page.
The descriptive drawing is the architect’s communication vector. It allows you to show, but also to see”what it gives”. The prescriptive design is the one that will allow the construction, the realization of the building. Finally, the speculative drawing is the one that we have mentioned the most until now, the main support of the creative and conceptual activity. However, this decomposition does not result in an impermeable separation of the functions of drawing in the architectural design process. These functions, isolated by Daniel E STEVEZ to organize his speech, overlap, and influence each other
throughout the process. It is moreover impossible to separate each of them into the three phases described above, even and especially if “common sense” suggests a certain distribution of these design functions during the time.
However, it turns out that they offer a clear vision of the different objectives of architectural drawing. In the context of our work (to offer new IT tools supporting creativity in the design), they will make it possible to identify the needs in the matter but especially the possible contributions, in particular in the preliminary phases of Design. In this context, the descriptive and prescriptive functions of drawing, as well as the techniques associated with them, do not seem essential at first glance. It is quite trivial within the framework of the prescriptive drawing, whose precise and finalized nature a priori map of the preliminary design phases. On the other hand, it is easier to see the descriptive drawing register in the first moments of the creative process, thus allowing an individual or collective evaluation of the result. However, we will see the relative importance that these two functions can take from the start of the design, as well as the importance that computer tools could (or rather should) give them at this