Determination of minimum dimensions for symbols of urban topographic maps

Abstract

This paper aims to define criteria to stablish minimum dimension for symbology standardization of urban topographic maps. This work is part of a major research whose objective is to propose and validate a methodology to produce topographic maps by automated cartographic generalization in Brazil. The automation of this process requires the knowledge of minimum dimension of sizes and distances to define and identify representation problems.  Paraná topographic maps of urban areas are at 1: 2,000 scale and maps at smaller scales can be produced by compilation from maps at larger scales and feature selection. Hence, there are cartographic products with representation problems. Cartographic generalization ensures that the topographic maps are legible. There is a proposal for symbology standardization for Paraná topographic mapping of urban areas, at 1:2,000 scale, but there are not recommendations for symbols when the map is produced by cartographic generalization. Therefore, it was necessary to develop visual perception tests to evaluate minimum sizes and minimum distances for colored symbols for buildings, property limits and streets features. The results indicate that minimum dimensions of size and distance are not universal values regarding topographic mapping, since visual perception is influenced by different colors of symbols.