Beam tracing is an algorithm to simulate wave propagation.It was developed in the context of computer graphics to render 3D scenes,but it has been also used in other similar areas such as acoustics andelectromagnetism simulations. Beam tracing is a derivative of the ray tracing algorithm that replaces rays, which have no thickness, with beams. Beams are shaped like unbounded pyramids, with (possibly complex) polygonal cross sections. Beam tracing was first proposed by Paul Heckbert and Pat Hanrahan. Beam tracing is related in concept to cone tracing.