Visualization of anatomical structures based on implicit surfaces and displacement mapping

Abstract

Implicit models provide an accurate and flexible representation of a surface. Although they have been widely used in modeling contexts, their application to visualization has been relatively limited due to rendering difficulties. Typical explicit triangulation of the surface, though effective, results in a redundant representation and a high load on the bus between the CPU and the graphics pipeline. In this work, we present an alternative method that allows high quality visualization of iso-surfaces with lower communication requirements. Our proposal is based on the combination of implicit surfaces with displacement mapping techniques. The application of displacement maps on a coarse mesh approximating the implicit model avoids the necessity of explicit triangulation and reduces the bus load without loss of image quality. The examination of the iso-surface contour, by means of a frequency analysis, allows for automatic creation of the displacement map which better suits to the implicit model in question. In this study we demonstrate the validity of the proposal as an efficient alternative to polygonization of implicit surfaces, thus opening many new possibilities to its application to volume visualization.