Pattern from objects

Generating patterns from Rhino objects

In RV2, three types of Rhino geometries can be used to generate a Pattern. These pattern generation features would be particularly useful when there is already an existing structure with a geometry that one would like to recreate the pattern for.

Nave Vault of the Sherborne Abbey, Dorset, UK (photo by Lawrence Lew)

. (a) Primal grid, directly using the rib layout and stereotomy of the vaults; (b) the resulting best-fit reciprocal (force) grid; and (c) axonometry of the target surface, constructed from documentation, and the best-fit thrust network with pipes proportional to the axial forces in the branches.

Photographs and diagrams of different rose windows with complex mullion geometries, showing from left to right an outside picture, the equilibrated and piped form diagram, and the reciprocal force diagram: (a) Notre Dame de Mantes, France; (b) Notre Dame de Chartres, France (Photo by Holly Hayes); (c) Durham Cathedral, England (Photo by Carcharoth on Wikipedia); (d) Notre Dame de Paris, France (Photo by Ellen Brown); (e) Bisshop’s Eye of Lincoln Cathedral, England (Photo from Cornell University Library); (f) Sainte-Chapelle Paris, France.

"Three-dimensional equilibrium analysis of gothic masonry vaults" (Block and Lachauer, 2014)

From lines

One of the simplest, and the most manual, way to make the Pattern is to draw the edges of the Pattern as Rhino lines. Each edge of the Pattern should be an individual line; all lines should be broken at all line intersections. In other words, these lines may not be overlapping.

Pattern is a COMPAS mesh object. A mesh datastructure is network of faces, where the connectivities of the faces are defined by halfedge adjacencies. Therefore, the input set of lines must consist of closed loops of lines representing the faces of the Pattern. If there are closed loops of lines, a Pattern will be generated and all lines that do not form a closed loop, such as the "leaf" edges will be omitted.

From mesh

A Rhino mesh object can be used to create a Pattern. Since a Pattern is also a mesh object, the vertices and edges can be directly used to create the vertices and edges of the Pattern.

From surface

A non-trimmed Rhino NURBS surface can be used to generate a Pattern. UV mapping of the surface is used to subdivide the Pattern, based on a subdivision value for U and V. Please refer to the first tutorial example to see how this feature is used.

RV2pattern_from_surface only works with untrimmed surfaces; the input surface cannot have more than four edges.