Textual Annotation in a Head Tracked, Stereoscopic Virtual Design Environment

In this paper we describe the textual annotation system we have implemented in CHaMUE, our Collaborative Haptic Mark-Up Environment software. This head tracked, stereoscopic virtual environment for design review allows remote participants to critique and refine product design ideas in real time, both by drawing on 3D virtual representations of the objects and by placing textual annotations linked to specific object features. Each textual annotation is displayed in a floating note with a 3D line path connecting the note with the point being referenced on the object geometry. The exact note positions and the 3D paths are automatically adjusted on a per-user basis according to each user’s current viewing position, balancing the ease of associating each note with its reference point on the object and the occlusion of both paths and the object under discussion. We discuss evaluation criteria for judging well placed notes and well chosen paths, and address the challenges posed by stereoscopic vision and head tracking to optimal note placement and path generation.