Architectural visualization has long been a post-design endeavor: the designer produces visual materials after one or more design schemes are available. In a traditional design process, post-design visualization is ubiquitous and takes varied form in macro or micro level. Regardless of media forms and methods of production, post-design visualization always comes after the designer conceives and iterates formal solutions. Computer-generated imagery has emerged as the most employed architectural visualization method, gradually making obsolete manually illustrated renderings. Nevertheless, the traditional design process shows little adaption in the role or positioning of visualization with the advent of the digital age. Whether the designer makes a speedy watercolor sketch in minutes or spend hours on a photorealistic rendering, visualization is a following step in the iterative cycles of design exploration and is unambivalently distinguished from the preceding steps. This reality is epitomized by today’s digital tools for architectural design: all design programs introduce a distinct set of interfaces and operative procedures (e.g. 2D interfaces based on parallel projections) for designers to make substantial design decisions before they move on to produce digital renderings in a separate software environment, such as a render plugin (e.g. V-Ray, Maxwell, Corona, and Enscape) or a standalone render platform (e.g. Lumion and Atlantis).
As architectural designers take post-design visualization for granted, their typical workflows diminish the value of visualization in design. The fast evolution of computer graphics has significantly enlarged the capacity of architectural visualization. Market standard rendering programs nowadays can generate very accurate presentation of 3D forms in light, yielding reliable visual feedback about formal schemes regarding views, materials, and lighting. Some physically based rendering (PBR) applications (e.g. Maxwell and Thea Render) even elevate architectural visualization to the level of photometric simulation. However, a design process with post-design visualization means the designer cannot capitalize on any visualization outcomes to inform design decision-making. Without access to immediate visualization feedback, most designers literally rely on imagination (though past design experience does help to some extent) when they intensively examine multiple design variables and seeks a difficult equilibrium among them.