SecondSkin: Sketch-based Construction of Layered 3D Models

摘要

SecondSkin is a sketch-based modeling system focused on the creationrnof structures comprised of layered, shape interdependent 3Drnvolumes. Our approach is built on three novel insights gleanedrnfrom an analysis of representative artist sketches. First, we observernthat a closed loop of strokes typically define surface patches thatrnbound volumes in conjunction with underlying surfaces. Second,rna significant majority of these strokes map to a small set of curvetypes,rnthat describe the 3D geometric relationship between the strokernand underlying layer geometry. Third, we find that a few simplerngeometric features allow us to consistently classify 2D strokes tornour proposed set of 3D curve-types. Our algorithm thus processesrnstrokes as they are drawn, identifies their curve-type, and interpretsrnthem as 3D curves on and around underlying 3D geometry, usingrnother connected 3D curves for context. Curve loops are automaticallyrnsurfaced and turned into volumes bound to the underlying layer,rncreating additional curves and surfaces as necessary. Stroke classificationrnby 15 viewers on a suite of ground truth sketches validates ourrncurve-types and classification algorithm. We evaluate SecondSkinrnvia a compelling gallery of layered 3D models that would be tediousrnto produce using current sketch modelers.