Capable or even noted architects, landscape architects, and planners designed some projects; others have benefited from the thoughtful, caring actions of citizens. 1994. Mandates, Plans, and Planners. The spatial distribution of population is therefore a static representation of the city when its people are at home, while the pattern of trips is a schematic view of the complex trajectories that these same people will follow during the time they are not at home. The only constraint will be to make sure that the conventions used to build the 3-dimensional representation of population are consistent across cities. The spatial structure of the cities shown in Fig. 1 appears complex. Fig. 1. The spatial structure of seven cities. This figure shows the spatial distribution of the population-at midnight-of 7 large world cities.