Defining Reality in Virtual Reality: Exploring Visual Appearance and Spatial Experience Focusing on Colour

Doctoral thesis, 2009

Today, different actors in the design process have communication difficulties in visualizing and predicting how the not yet built environment will be experienced. Visually believable virtual environments (VEs) can make it easier for architects, users and clients to participate in the planning process. This thesis deals with the difficulties of translating reality into digital counterparts, focusing on visual appearance (particularly colour) and spatial experience. The goal is to develop knowledge of how different aspects of a VE, especially light and colour, affect the spatial experience; and thus to contribute to a better understanding of the prerequisites for visualizing believable spatial VR-models. The main aims are to 1) identify problems and test solutions for simulating realistic spatial colour and light in VR; and 2) develop knowledge of the spatial conditions in VR required to convey believable experiences; and evaluate different ways of visualizing spatial experiences. The studies are conducted from an architectural perspective; i.e. the whole of the spatial settings is considered, which is a complex task. One important contribution therefore concerns the methodology. Different approaches were used: 1) a literature review of relevant research areas; 2) a comparison between existing studies on colour appearance in 2D vs 3D; 3) a comparison between a real room and different VR-simulations; 4) elaborations with an algorithm for colour correction; 5) reflections in action on a demonstrator for correct appearance and experience; and 6) an evaluation of texture-styles with non-photorealistic expressions. The results showed various problems related to the translation and comparison of reality to VR. The studies pointed out the significance of inter-reflections; colour variations; perceived colour of light and shadowing for the visual appearance in real rooms. Some differences in VR were connected to arbitrary parameter settings in the software; heavily simplified chromatic information on illumination; and incorrect inter-reflections. The models were experienced differently depending on the application. Various spatial differences between reality and VR could be solved by visual compensation. The study with texture-styles pointed out the significance of varying visual expressions in VR-models.