line interpolate points
A Node module that interpolates the coordinates of any number of equidistant points along a line composed of one or
more line segments, at an optional offset. It's particularly useful for GIS applications, and is analogous to the
PostGIS ST_LineInterpolatePoint()
and Python Shapely's shapely.geometry.LineString.interpolate()
. Here's an example
of points interpolated over different multi-segment lines (the second group has been offset):
the api
The module exports a single function, interpolateLineRange( ctrlPoints, number, offsetDist )
.
ctrlPoints
is an array of 2D point arrays, like[ [ 5, 10 ], [ 7, 10 ], [ 14, 13 ] ]
number
is the number of points to interpolate (the endpoints included)offsetDist
is an optional distance to move each interpolated point from its container line segment.minGap
is an optional minimum distance to maintain between subsequent interpolated points (offsetDist
is not taken into account here, as spacing between points is measured along the LineString). May decreasenumber
if the gap between neighbors with that number of points would be lower thanminGap
.
> var interpolateLineRange = > 3 10 4 10 > 3 10 33333333333333335 10 3666666666666667 10 4 10 > 3 4 3 6723154621172782 3 9446309242345563 39354486533919397 12387971226535829 5008151811686941 14890945262557498 6080854969981942 17393919298579167
Install Dev Dependencies
$ npm install
Contributing
Please fork and pull request against upstream master on a feature branch. Please provide unit tests and script fixtures
in the test
directory.
Running Unit Tests
$ npm test
Continuous Integration
Travis tests every release against node version 0.10