Polyhedral Shapes of CeO2Nanoparticles

CSG Feature Trees from Engineering Sketches of Polyhedral Shapes

We give a method to obtain a 3D CSG model from a 2D engineering wireframe sketch which depicts a polyhedral shape. The method finds a CSG feature tree compatible with a reverse design history of a 2D line-drawing obtained by vectorising the sketch. The process used seeks the CSG feature tree recursively, combining all design or manufacturing features embedded in the sketch, proceeding in revers...

Perceiving Ribs in Single-View Wireframe Sketches of Polyhedral Shapes

As part of a strategy for creating 3D models of engineering objects from sketched input, we attempt to identify design features, geometrical structures within objects with a functional meaning. Our input is a 2D B-Rep derived from a single view sketch of a polyhedral shape. In this paper, we show how to use suitable cues to identify algorithmically two additive engineering design features, angu...

A topologically robust algorithm for Boolean operations on polyhedral shapes using approximate arithmetic

We present a topologically robust algorithm for Boolean operations on polyhedral boundary models. The algorithm can be proved always to generate a result with valid connectivity if the input shape representations have valid connectivity, irrespective of the type of arithmetic used or the extent of numerical errors in the computations or input data. The main part of the algorithm is based on a s...

A Method for Reconstructing Sketched Polyhedral Shapes with Rounds and Fillets

In this paper we present a method for detecting rounds and fillets in engineering sketches and drawings, and automatically generating a 3D model of the corresponding object, with rounds and fillets applied. This method is useful both as a component of computer-aided sketching tools and in determining design intent—although rounds and fillets are common in engineering parts, they often conceal d...

Optimization of polyhedral terrains