We first present a novel approach to sketching 2D curves with minimally varying curvature as piecewise clothoids. A stable and efficient algorithm fits a sketched piecewise linear curve using a number of clothoid segments with G2 continuity based on a specified error tolerance.
We then present a system for conceptually sketching 3D layouts for road and other
path networks. Our system makes four key contributions. First, we generate paths
with piecewise linear curvature by fitting 2D clothoid curves to strokes sketched on a
terrain. Second, the height of paths above the terrain is automatically determined using
a new constraint optimization formulation of the occlusion relationships between sketched
strokes. Third, we present the break-out lens, a novel widget inspired by break-out views used in engineering visualization, to facilitate the in-context and interactive manipulation of paths from alternate view points. Finally, our path construction is terrain sensitive.
|Date||30 July 2008|
|Source Sets||Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada|
|Format||5716877 bytes, application/pdf|
Page generated in 0.0018 seconds