Create isobands and isolines directly from a Raster with the marching-squares algorithm
npm install raster-marching-squares
Marching squares isobands and isolines ready for using along with d3 maps.
The marching squares algorithm code is taken from the MarchingSquares.js project by Ronny Lorenz, adapted to work with nodejs.
INSTALL
-------
Using nodejs:
npm install raster-marching-squares
From the browser:
Download https://github.com/rveciana/raster-marching-squares/blob/master/build/d3-marching-squares.min.js
USAGE
-----
var intervals = [0, 5, 10, 15, 20, 25, 30, 35, 40];
var bands = rastertools.isobands(rasterData, geoTransform, intervals);
var lines = rastertools.isolines(rasterData, geoTransform, intervals);
rasterData* is a 2D array with the values
geoTransform* is an array following the conventions of the GDAL data model
EXAMPLES
--------
* Isolines with labels: http://bl.ocks.org/rveciana/bef48021e38a77a520109d2088bff9eb
* Simple isobands: http://bl.ocks.org/rveciana/de0bd586eafd7fcdfe29227ccbdcd511