= ExtractTtc: Ruby gem to extract TTF from TTC

== Purpose

The gem lets you extract individual TrueType font files (`.ttf`) from a TrueType Collection file (`.ttc`).

`ExtractTtc` wraps functionality provided by `stripttc.c`, originally from the
https://github.com/fontforge/fontforge[FontForge project] as an FFI extension.

Specifically, `stripttc.c` is part of the `contribs` directory of FontForge, which
is
https://github.com/fontforge/fontforge/blob/21ad4a18fb3d4becfe566d8215eba4483b0ddc4b/contrib/CMakeLists.txt#L1[assigned]
the
https://github.com/fontforge/fontforge/blob/21ad4a18fb3d4becfe566d8215eba4483b0ddc4b/LICENSE#L12-L57[BSD 3-Clause license].


== Installation

Add this line to your application's `Gemfile`:

[source,ruby]
----
gem 'extract_ttc'
----

And then execute:

[source,sh]
----
$ bundle install
----

Or install it yourself as:

[source,sh]
----
$ gem install extract_ttc
----

== Usage

[source,ruby]
----
ExtractTtc.extract("path/to/ttc/Helvetica.ttc")
----

Would extract contained TTF files from TTC to a current directory.


== Development

We are following Sandi Metz's Rules for this gem, you can read the
http://robots.thoughtbot.com/post/50655960596/sandi-metz-rules-for-developers[description of the rules here].
All new code should follow these
rules. If you make changes in a pre-existing file that violates these rules you
should fix the violations as part of your contribution.

=== Setup

Clone the repository:

[source,sh]
----
git clone https://github.com/fontist/extract_ttc
----

Setup your environment:

[source,sh]
----
bin/setup
----

Run the test suite:

[source,sh]
----
bundle exec rspec
----

If any changes are made in the C code, then the extension needs to be recompiled:

[source,sh]
----
bundle exec rake recompile
----

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 tags, and push the `.gem` file to https://rubygems.org[rubygems.org].


== Contributing

First, thank you for contributing! We love pull requests from everyone. By
participating in this project, you hereby grant https://www.ribose.com[Ribose Inc.] the
right to grant or transfer an unlimited number of non exclusive licenses or
sub-licenses to third parties, under the copyright covering the contribution
to use the contribution by all means.

Here are a few technical guidelines to follow:

1. Open an https://github.com/fontist/extract_ttc/issues[issue] to discuss a new feature.
1. Write tests to support your new feature.
1. Make sure the entire test suite passes locally and on CI.
1. Open a Pull Request.
1. https://github.com/thoughtbot/guides/tree/master/protocol/git#write-a-feature[Squash your commits]
  after receiving feedback.
1. Party!


== License

This gem is distributed with a BSD 3-Clause license.

`stripttc.c` is obtained from:
https://github.com/fontforge/fontforge/blob/master/contrib/fonttools/stripttc.c

The BSD 3-Clause licence for `stripttc.c` is provided in `ext/stripttc/LICENSE`.

This gem is developed, maintained and funded by https://www.ribose.com/[Ribose Inc.]