Straight Skeleton (imperfect)

Straight Skeleton from HEM faces Inspired by a comment, this morning I played around with the idea of composing straight skeletons for the faces generated by the Half-Edge Mesh Definition posted earlier. A polygon’s straight skeleton resembles the voronoi skeleton or medial axis, but is composed of only straight segments (and typically fewer of them, … Continue reading

HEM functions

Offset, Distance, and Walk over Half-Edge Mesh Presented here are three functions for working with Half-Edge Meshes in Grasshopper. The first uses the lists of vertex’ incident edges (vIE) to calculate the bisecting angles at intersections in-between branches and create an offset of the graph which can be uniquely defined at every vertex (in black … Continue reading

Half-Edge Mesh

Each segment of this network has two half-edges Though the logic behind the data-structure of a half-edge mesh can be difficult or unintuitive to work with at first, once it becomes clear, it can become difficult to imagine working without recourse to functions that will tell you which face an edge is adjacent to, which … Continue reading

Mesh Import

Rhino to Processing This sketch expands on the earlier Half-Edge Mesh sketch, demonstrating how to generate a large HEM class from text files containing the vertex positions and the vertex indices for each face as comma separated lists. (To generate these .txt files from Rhino via Rhinoscript see this post.) The difference between this sketch … Continue reading

Mesh Export

Rhino to Processing In a previous post I covered the implementation of a Half-Edged Mesh as a class in Processing. In that definition, however, both the vertex coordinates and face indexing were hard-coded in the body of the script (Lines 8-9). This may be acceptable for a mesh with only 16 faces, but for most … Continue reading

Half-Edge Mesh

¬†key to the HEM class methods and face splitting modifier This is a class to be used with the Anar+ library for Processing to create a half-edge (or doubly-connected) mesh datastructure which uses the parametric geometry of Anar’s faces, and points. The schema for this HEM class is based on the description of doubly-connected edge … Continue reading

Wind Impact Simulation:

Feasibility study of renewable energy sources. Ten years of monthly average wind directions and speed (via Wolfram), in reaction with topographic variations simulated in Processing for visual analysis using the Anar+ library and a custom built half-edge mesh class. Darkness of the line indicates proximity to ground. Red squares mark wind impact with and deflection … Continue reading