In this paper we present the Virtual Magic Lantern (VML), an interaction tool tailored to facilitate volumetric data inspection. It behaves like a lantern whose virtual illumination cone provides the focal region which is visualized using a secondary transfer function or different rendering style. This may be used for simple visual inspection, surgery planning, or injure diagnosis. The VML is a particularly friendly and intuitive interaction tool suitable for an immersive Virtual Reality setup with a large screen, where the user moves a Wanda device, like a lantern pointing to the model. We show that this inspection metaphor can be efficiently and easily adapted to a GPU ray casting volume visualization algorithm. We also present the Virtual Magic Window (VMW) metaphor as an efficient collateral implementation of the VML, that can be seen as a restricted case where the lantern illuminates following the viewing direction, through a virtual window created as the intersection of the virtual lantern (guided by the Wanda device) and the bounding box of the volume.

Peer Reviewed