Noname manuscript No. (will be inserted by the editor) Illustrative multilevel focus+context visualization along snaking paths Jeffrey F. Packer · Mahmudul Hasan · Faramarz F. Samavati Received: date / Accepted: date Abstract Artistic anatomical illustrations often focus on cross sections of long, layered, cylindrical structures. Such illustrations emphasize structures along transitions between focal points over a snaking path that optimally traverses the span of a limited space. The transitions between focal points form a multilevel visualization hierarchy. In this article, we present an approach to automatically create focus+context visualizations of the described form. First, a method to automatically create a snaking path through space by applying a pathfinding algorithm is presented. A 3D curve is created based on a 2D snaking path. Then we describe a process to deform cylindrical structures in segmented volumetric models along the 3D curve and provide preliminary ge- ometric models as templates for artists to build upon. Our constrained volume sculpting method enables the removal of occluding material to reveal cylindrical struc- tures of interest intended for such deformation. Finally, we present a set of created visualizations that demon- strates the flexibility of our approach and effectively mimics the form of visualization observed in motivating illustrations. Keywords Illustrative visualization · Focus+context visualization · Multilevel visualization hierarchy · Volume deformation · Constrained volume sculpting · Pathfinding Supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada, Alberta Innovates – Technology Futures (AITF), Alberta Enterprise and Advanced Education, and Network of Centres of Excellence (NCE) of Canada in Graphics, Animation and New Media (GRAND). J. F. Packer · M. Hasan () · F. F. Samavati Department of Computer Science University of Calgary, Calgary, Alberta, Canada e-mail: mhasan@ucalgary.ca Fig. 1 An illustration motivating the work in this article. A human limb is cut revealing a cross section of the mus- cle (upper left). The structures that compose its interior are illustrated along a snaking path. This multiscale image demon- strates all structures of muscle tissue down to the microscopic level. (Illustration courtesy of Natasha Shevchenko. Used with permission.) Mathematics Subject Classification (2000) 65D18 · 68U05 · 76M27 1 Introduction Context and motivation. Artistic medical illustrations often depict structures in such a way that emphasizes certain features while revealing their nature as a whole. For example, Fig. 1 shows human muscle tissue drawn to emphasize the structure of its various layers while demonstrating that the tissue as a whole is made up of long strands wrapped together. The work in this article is motivated by such artistic illustrations that depict a multiscale visualization of a cylindrical structure with several levels of focus+context. A focus+context effect is