Some of the practical issues that are involved in computer-generated contour rendering are described in this section. Some surfaces should not have contours between them for example, if they are part of the same object, but have been modeled separately. Therefore, it is sometimes necessary to specify pairs of surfaces that should not have a contour between them. We have found that using the contour type of the frontmost object works well. However, no object is in front at places where two objects abut, so some other strategy must be used there.
Contours can be on top of each other in image space.
Per H. Christensen is working at mental images in Berlin, Germany. His work there focuses mainly on contour rendering, fast motion blur and global illumination. The topic of his research was hierarchical finite-element methods for simulation of global illumination. In a previous life, he received a master s degree in electrical engineering from the Technical University of Denmark. The copyright of articles and images printed remains with the author unless otherwise indicated.