Partitioning of surfaces of structures in propagation modelling

A system and method for ray launching in electromagnetic wave propagation modeling. A data-processing system receives a dataset that is representative of one or more structures within an environment, including a structure that is defined in the dataset as having at least a first surface. The data-processing system establishes a bounding box that is representative of the first surface and partitions at least a portion of the bounding box into a first set of tiles. The data-processing system then projects a first set of ray tubes from a predetermined point within the environment, to the tiles in the first set of tiles. Each ray tube in the first set of ray tubes is defined by a corresponding tile in the first set of tiles. The data-processing system evaluates the incidence of bounced ray tubes at a predetermined receive point within the environment and presents a propagation result that is based on the evaluated incidence.