FlexiblePolyline

The flexible polyline encoding from heremaps is a lossy compressed representation of a list of coordinate pairs or coordinate triples.

It achieves that by:

1. Reducing the decimal digits of each value.
2. Encoding only the offset from the previous point.
3. Using variable length for each coordinate delta.
4. Using 64 URL-safe characters to display the result.

For more information, visit: https://github.com/heremaps/flexible-polyline

Add this line to your application's Gemfile:

gem 'flexible_polyline'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install flexible_polyline

Encode:

 FlexiblePolyline::Encoder.encode(third_dim: 1, precision: 8, third_dim_precision: 8, positions: [[-96.628241002595274, 34.155307026461529, 228.390420353746407]])

=> "B4gBnq_r-_R-suzyrGm_vgqxqB"

Decode:

FlexiblePolyline::Decoder.decode('B4gBnq_r-_R-suzyrGm_vgqxqB')

=>

{"header": {"precision": 8, "third_dim": 1, "third_dim_precision": 8}, "positions": [[-96.628241, 34.15530703, 228.39042035]]} 

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/ioki-mobility/flexible_polyline.

The gem is available as open source under the terms of the MIT License.