Research On Offset Surface And Surface From Cross Sections Construction Algorithm

Offset surface, section surface and developable surface reconstruction are hot topics in Computer Graphics and industrial design and other domains, be requested and applied ranging from CAD/CAM, to GIS and bio-modeling.Offset algorithm is designed based on different geometry shape of curves and surfaces, Special curves and surfaces can be recognized and offset precisely according to their equations; For free-form curves and surfaces, decomposing them into Bezier segments or surface patches, then sampling each segments or patches and removing duplicate points; Creating offset curve or surface by interpolating offset points. Surface construction from parallel cross sections algorithm, based on NURBS surface trimming and Coons surface filling, construction work according to three kinds of relations among adjacent contours; The degree of the reconstructed surface can be controlled. Developable surface algorithm researched on general developable and triangulation cases; Cylinder and conic surface can be calculated from their equations; Approximation with triangle mesh based on split and sampling on NURBS surface, by improving the density of sampling points can approximation the original surface finely; Developable triangulation based on sketch algorithm can construct a developable surface for the designer who is not a expert in geometry knowledge.The offset curves and surfaces avoid no needed knot vectors and results have less control points; By adding direction guide curve in skinning surface construction, the result patches can keep continues; Developable surface reconstructed from three problems, the designer who with no professional geometry knowledge can create a surface in an intuitive way.