Abstract: Labels effectively convey co-referential relations between textual and visual elements and are a powerful tool to support learning tasks. Therefore, almost all illustrations in scientific or technical documents employ a large number of labels. This paper introduces a novel approach to integrate internal and external labels into projections of complex 3D models in the fashion of hand-made illustrations. The real-time label layout algorithms proposed in the paper balance a number of conflicting requirements such as unambiguity, readability, aesthetic considerations and frame-coherency.