3D Viewpoint Management and Navigation in Urban Planning: Application to the Exploratory Phase

3D geovisualization is essential in urban planning as it assists the analysis of geospatial
data and decision making in the design and development of land use and built environment.
However, we noted that 3D geospatial models are commonly visualized arbitrarily as current 3D
viewers often lack of design instructions to assist end users. This is especially the case for the
occlusion management in most 3D environments where the high density and diversity of 3D data to
be displayed require efficient visualization techniques for extracting all the geoinformation. In this
paper, we propose a theoretical and operational solution to manage occlusion by automatically
computing best viewpoints. Based on user’s parameters, a viewpoint management algorithm initially
calculates optimal camera settings for visualizing a set of 3D objects of interest through parallel
projections. Precomputed points of view are then integrated into a flythrough creation algorithm
for producing an automatic navigation within the 3D geospatial model. The algorithm’s usability is
illustrated within the scope of a fictive exploratory phase for the public transport services access in
the European quarter of Brussels. Eventually, the proposed algorithms may also assist additional
urban planning phases in achieving their purposes.