- [Learn about CLAP](#learn-about-clap) - [Entry point](#entry-point) - [Extensions](#extensions) - [Fundamental extensions](#fundamental-extensions) - [Support extensions](#support-extensions) - [Deeper Host integration](#deeper-host-integration) - [Third-party extensions](#third-party-extensions) - [Adapters](#adapters) - [Resources](#resources) - [Examples](#examples) - [Community related projects](#community-related-projects) - [Programming Language Bindings](#programming-language-bindings) - [Artwork](#artwork) # Learn about CLAP CLAP stands for **CL**ever **A**udio **P**lugin. It is an interface that provides a stable ABI to define a standard for *Digital Audio Workstations* and audio plugins (synthesizers, audio effects, ...) to work together. The ABI, or **A**pplication **B**inary **I**nterface, serves as a means of communication between a host and a plugin. It provides backwards compatibility, that is, a plugin binary compiled with CLAP 1.x can be loaded by any other CLAP 1.y. To work with CLAP, include [clap/clap.h](include/clap/clap.h). To also include the draft extensions, include [clap/all.h](include/clap/all.h). The two most important objects are `clap_host` and `clap_plugin`. [src/plugin-template.c](src/plugin-template.c) is a very minimal example which demonstrates how to wire a CLAP plugin. ## Entry point The entry point is declared in [entry.h](include/clap/entry.h). ## Extensions Most features come from extensions, which are in fact C interfaces. ```C // host extension const clap_host_log *log = host->extension(host, CLAP_EXT_LOG); if (log) log->log(host, CLAP_LOG_INFO, "Hello World! ;^)"); // plugin extension const clap_plugin_params *params = plugin->extension(plugin, CLAP_EXT_PARAMS); if (params) { uint32_t paramsCount = params->count(plugin); // ... } ``` The extensions are defined in the [ext](include/clap/ext) folder. Some extensions are still in the progress of being designed and they are in the [draft](include/clap/ext/draft) folder. An extension comes with: - a header `#include ` - an extension identifier: `#define CLAP_EXT_XXX "clap/XXX"` - host interfaces are named like: `struct clap_host_xxx` - plugin interfaces are named like: `struct clap_plugin_xxx` - each method must have a clear thread specification You can create your own extensions and share them. Make sure that the extension identifier: - includes versioning in case the ABI breaks - is a unique identifier **All strings are valid UTF-8**. ## Fundamental extensions This is a list of the extensions that you most likely want to implement and use to get a basic plugin experience: - [state](include/clap/ext/state.h), save and load the plugin state - [state-context](include/clap/ext/state-context.h), same as state but with additional context info (preset, duplicate, project) - [resource-directory](include/clap/ext/draft/resource-directory.h), host provided folder for the plugin to save extra resource like multi-samples, ... (draft) - [params](include/clap/ext/params.h), parameters management - [note-ports](include/clap/ext/note-ports.h), define the note ports - [audio-ports](include/clap/ext/audio-ports.h), define the audio ports - [surround](include/clap/ext/surround.h), inspect surround channel mapping - [ambisonic](include/clap/ext/draft/ambisonic.h), inspect ambisonic channel mapping - [configurable-audio-ports](include/clap/ext/configurable-audio-ports.h), request the plugin to apply a given configuration - [audio-ports-config](include/clap/ext/audio-ports-config.h), simple list of pre-defined audio ports configurations, meant to be exposed to the user - [audio-ports-activation](include/clap/ext/audio-ports-activation.h), activate and deactivate a given audio port - [extensible-audio-ports](include/clap/ext/draft/extensible-audio-ports.h), let the host add audio ports to the plugin, this is useful for dynamic number of audio inputs (draft) - [render](include/clap/ext/render.h), renders realtime or offline - [latency](include/clap/ext/latency.h), report the plugin latency - [tail](include/clap/ext/tail.h), processing tail length - [gui](include/clap/ext/gui.h), generic gui controller - [voice-info](include/clap/ext/voice-info.h), let the host know how many voices the plugin has, this is important for polyphonic modulations - [track-info](include/clap/ext/track-info.h), give some info to the plugin about the track it belongs to - [tuning](include/clap/ext/draft/tuning.h), host provided microtuning (draft) - [triggers](include/clap/ext/draft/triggers.h), plugin's triggers, similar to parameters but stateless ## Support extensions - [thread-check](include/clap/ext/thread-check.h), check which thread you are currently on, useful for correctness validation - [thread-pool](include/clap/ext/thread-pool.h), use the host thread pool - [log](include/clap/ext/log.h), lets the host aggregate plugin logs - [timer-support](include/clap/ext/timer-support.h), lets the plugin register timer handlers - [posix-fd-support](include/clap/ext/posix-fd-support.h), lets the plugin register I/O handlers ## Deeper Host integration - [remote-controls](include/clap/ext/remote-controls.h), bank of controls that can be mapped on a controlles with 8 knobs - [preset-discovery](include/clap/factory/preset-discovery.h), let the host index the plugin's preset in their native file format - [preset-load](include/clap/ext/preset-load.h), let the host ask the plugin to load a preset - [param-indication](include/clap/ext/param-indication.h), let the plugin know when a physical control is mapped to a parameter and if there is automation data - [note-name](include/clap/ext/note-name.h), give a name to notes, useful for drum machines - [transport-control](include/clap/ext/draft/transport-control.h), let the plugin control the host's transport (draft) - [context-menu](include/clap/ext/context-menu.h), exchange context menu entries between host and plugin, let the plugin ask the host to popup its own context menu ## Third-party extensions - [`cockos.reaper_extension`](https://github.com/justinfrankel/reaper-sdk/blob/main/reaper-plugins/reaper_plugin.h#L138), access the [REAPER](http://reaper.fm) API # Adapters - [clap-wrapper](https://github.com/free-audio/clap-wrapper), wrappers for using CLAP in other plugin environments # Resources - [clap-validator](https://github.com/robbert-vdh/clap-validator), a validator and automatic test suite for CLAP plugins. - [clapdb](https://clapdb.tech), a list of plugins and DAWs which supports CLAP ## Examples - [clap-host](https://github.com/free-audio/clap-host), very simple host - [clap-plugins](https://github.com/free-audio/clap-plugins), very simple plugins ## Community related projects - [clap-juce-extension](https://github.com/free-audio/clap-juce-extension), juce add-on - [MIP2](https://github.com/skei/MIP2), host and plugins - [Avendish](https://github.com/celtera/avendish), a reflection-based API for media plug-ins in C++ which supports Clap - [NIH-plug](https://github.com/robbert-vdh/nih-plug), an API-agnostic, Rust-based plugin framework aiming to reduce boilerplate without getting in your way - [iPlug2](https://iplug2.github.io), a liberally licensed C++ audio plug-in framework that supports Clap ## Programming Language Bindings - [clap-sys](https://github.com/glowcoil/clap-sys), rust binding - [CLAP-for-Delphi](https://github.com/Bremmers/CLAP-for-Delphi), Delphi binding ## Artwork - [CLAP Logo Pack.zip](https://github.com/free-audio/clap/files/8805281/CLAP.Logo.Pack.zip)