A typical industrial design modelling scenario involves defining the overall shape of a product followed by adding detail features. Procedural features are well-established in computer aided design (CAD) involving regular forms, but are less applicable to free-form modelling involving subdivision surfaces. Current approaches do not generate sparse subdivision control meshes as output, which is why free-form features are manually modelled into subdivision control meshes by domain experts. Domain experts change the local topology of the subdivision control mesh to incorporate features into the surface, without increasing the mesh density unnecessarily and carefully avoiding the appearance of artefacts.In this paper we show how to translate this expert knowledge to grammar rules. The rules may then be invoked in an interactive system to automatically apply features to subdivision surfaces. Graphical abstractDisplay Omitted HighlightsA novel method for adding freeform detail features to subdivision surfaces.Both input and output are industry-standard Catmull-Clark subdivision meshes.Expert knowledge about mesh topology modification is encoded as graph grammar rules.Resulting mesh contains few new control points than with comparable methods.Rules can encode domain-specific interactions between features.
['Wolfgang Thaller', 'Ursula H. Augsdörfer', 'Dieter W. Fellner']
Procedural mesh features applied to subdivision surfaces using graph grammars