Efficient View Management for Dynamic Annotation Placement in Virtual Landscapes

We present a dynamic placement technique for annotations of virtual landscapes that is based on efficient view management. Annotations represent textual or symbolic descriptions and provide explanatory or thematic information associated with spatial positions. The technique handles external annotations as 2.5 dimensional objects and adjusts their positions with respect to available space in the view-plane. The approach intends to place labels without occlusions and, if this cannot be achieved, favors those annotations that are close to the observer. This technique solves the visibility problem of annotations in an approximate but user-centric way. It operates in real-time and therefore can be applied to interactive virtual landscapes. Additionally, the approach can be configured to fine tune the trade off between placement quality and processing time with a single parameter.