The Ant Colony Optimization algorithm - a multi-agent approach tocombinatorial optimization problems - is introduced for a simple raytracing performed on only an ordinary bitmap describing atwo-dimensional scenario. This bitmap can be obtained as a simple scanwhere different colors represent different mediums or obstacles. It isshown that using the presented algorithm a path minimizing the wavetraveling time can be found according to the Fermat's principle. Anexample of practical application is a simple ray tracing performed ononly an ordinary scanned bitmap of the city map. Together with theBerg's recursive model a non-line-of-sight path loss could becalculated without any need of building database. In this way thecoverage predictions for urban microcells could become extremely easyand fast to apply.