rle-components

rle-components

Connected component labelling for narrowband level sets. It is part of the rle-* collection of libraries for processing narrow band level sets.

Usage/Installation

First, install the package using npm:

npm install rle-components

Then you can use the library to split a level set into its connected components. For example:

//First create a volume
var volume = require("rle-sample").solid.dense([-32, -32, -32], [32, 32, 32], function(x) {
  var s = Math.sin(x[0]) + Math.sin(x[1]) + Math.sin(x[2]);
  var b = Math.max(Math.abs(x[0]), Math.abs(x[1]), Math.abs(x[2]));
  return Math.max(s + 2.2, b - 9.9);
});

//Then split into separate components
var components = require("rle-components").split(volume);

Here is the result:

You can try out a demo in your browser.

require("rle-components").label(volume[, link_func, solid_func])

This takes a narrowband level set as input and assigns labels to the components.

• volume is the level set we are labelling
• link_func(a,b) determines if two phases should be considered linked in the same component. By default, always returns true.
• solid_func(a) determines if a phase should be included in the components. By default, returns false for phase 0.

The result of calling the function is a labelStruct object which has the following properties:

• count The number of connected components
• labels An array of integers of length = volume.length() which gives the name of the connected component, starting at 0. Not solid components are labeled -1.

require("rle-components").split(volume[, labelStruct])

This splits a volume into a collection of volumes with different connected components.

• volume is the volume to split
• labelStruct (Optional) is the result of calling label() (see above) on the volume. If not specified, label is called with the default arguments.

Returns an array of of volumes representing the different connected components of volume

Credits

(c) 2013 Mikola Lysenko. BSD