Hydrogen is an advanced drum machine for GNU/Linux, Mac and Windows. Its main goal is to provide professional, yet simple and intuitive, pattern-based drum programming. Unlike other drum machines the C++ code base of Hydrogen and its slim Qt5-based GUI are tailored to be both memory-efficient and quite gentle in terms of CPU load. This makes it an excellent choice for older hardware or big setups consisting of numerous real-time audio programs.

Structure of the code

All C++ code of Hydrogen can be found in the src folder. The particular structure of this directory is meant to imitate the overall design of the application.

For a more thorough introduction please see the general design on Github.

Core

Hydrogen consists of a core, which is responsible for, among others, generating all audio, holding representations of all patterns, drumkits etc., for all interactions with the operation system and its audio driver, and for interpreting and sending MIDI signals.

GUI

The GUI, which was written in Qt5, is designed to be a completely separate entity. It is able to query and set various resources of the core and serves as the main method for the user to interact with the application (core).

Structure of the documentation

Both the documentation of the code base and the overall one you are reading right now are still under active development. If you have some insights into Hydrogen you want to share, we would be very happy about your contribution.

Modules

Since this project grew naturally (and quite big), the encapsulation of related classes/functions into namespaces might not be as good as it could be. To still provide an overview about separate topics, the documentation of the classes was grouped into logical units you can access in Modules. Core of hydrogen contains all classes and functions of the core while GUI of hydrogen encapsulates everything related to the Qt5-based GUI.

Namespace Members

Lists all members of the H2Core namespace encapsulating most classes and functions, which can be found in the src/core/ folder (see Structure of the code). Since Hydrogen does only contain this one namespace, this page might not be the most informative one. Data Structures might be a better alternative.

Data Structures

This page gives insights into all (documented) data structures of Hydrogen.

Files

The Files page provides you with lists all files touched by Doxygen while creating this documentation. It reproduces the folder hierarchy of the code (see Core) and allows you to view both the documentation and source code of each individual file.

Questions?

Get in touch with us via our mailing list or by filing an issue on our GitHub page.

Want to contribute?

Hydrogen is a community-driven project and critically depends on the commitment of volunteers. So, even if you are not an experienced C++ developer (yet), there are countless ways to contribute to this project, like improving the documentation and manual, translating the user manual, tweaking the design, making a donation etc. We are happy about all your efforts to contributed. The more people we are, the more awesome features we can provide. ;)

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