Architects are no longer limited to computer-aided design and drafting tools that convey abstract line and surface representations of designed spaces. Today architects rely upon accurate 3-d renderings to understand and convey the visual impact of proposed buildings. The use of design tools in this manner is the making of a new breed of design tools which the author calls "Computer Aided Perception." Successful use of rendering software in this manner depends upon an accurate real-world luminance to monitor display brightness (tone) mapping algorithm that considers the psychophysical constraints of the human eye-brain system. This paper establishes an experimental framework for validating the representation of discomfort glare in tone mapping algorithms from several software programs that claim to accurately render and/or display architectural spaces. Historical data from glare studies is compared with subjects’ survey responses to computer-displayed representations of the same glare evaluation experiments. A validated tone mapping operator enhances the reliability and repeatability of computer-based simulation and visualization technologies thereby improving the building industry’s ability to predict the visual impact of proposed architectural projects. Applications relevant to the findings of this study include improving designers ability to understand the nature of glare in daylit office environments. Secondary applications include high dynamic range photography, video game and environmental simulations, and general-purpose renderings for animations, film, and movie production.