3D Strokes on Visible Structures in Direct Volume Rendering (English)

In this paper we describe VisiTrace, a novel technique to draw 3D lines in direct volume rendered images. It allows to draw strokes in the 2D space of the screen to produce 3D lines that run on top or in the center of structures visible in the rendering. It is able to ignore structures that shortly occlude the structure that has been visible at the start of the stroke. For this purpose a shortest path algorithm finding the optimal curve in a specially designed graph is employed. We demonstrate the usefulness of the technique by applying it to image data from medicine and engineering, and show how it can be used to mark structures in the example data, and to automatically obtain good views toward these structures enabling faster navigation in the rendering.