hdng / packcircles

R package for random circle packing

packcircles

R package for circle packing.

This package provides functions to find non-overlapping arrangements of circles.

The function circleLayout attempts to arrange a set of circles of specified radii within a rectangle such that there is no-overlap between circles. The algorithm is adapted from an example written in Processing by Sean McCullough (which no longer seems to be available online). It involves iterative pair-repulsion, in which overlapping circles move away from each other. The distance moved by each circle is proportional to the radius of the other to approximate inertia (very loosely), so that when a small circle is overlapped by a large circle, the small circle moves furthest. This process is repeated iteratively until no more movement takes place (acceptable layout) or a maximum number of iterations is reached (layout failure). To avoid edge effects, the bounding rectangle is treated as a toroid. Each circle's centre is constrained to lie within the rectangle but its edges are allowed to extend outside.

The package also contains an initial Rcpp port of an algorithm described by Collins and Stephenson (2003) to find an arrangement of circles which corresponds to a graph of desired circle tangencies. The implementation is based on a Python version by David Eppstein (see CirclePack.py in the PADS library.

To install:

• the latest released version: install.packages("packcircles")
• the latest development version: install_github("mbedward/packcircles")