diff options
Diffstat (limited to 'plugins/eg-amp.lv2')
| -rw-r--r-- | plugins/eg-amp.lv2/README.txt | 19 | ||||
| -rw-r--r-- | plugins/eg-amp.lv2/amp.c | 230 | ||||
| -rw-r--r-- | plugins/eg-amp.lv2/amp.ttl | 90 | ||||
| -rw-r--r-- | plugins/eg-amp.lv2/manifest.ttl.in | 68 | ||||
| l--------- | plugins/eg-amp.lv2/waf | 1 | ||||
| -rw-r--r-- | plugins/eg-amp.lv2/wscript | 56 |
6 files changed, 464 insertions, 0 deletions
diff --git a/plugins/eg-amp.lv2/README.txt b/plugins/eg-amp.lv2/README.txt new file mode 100644 index 0000000..41683d3 --- /dev/null +++ b/plugins/eg-amp.lv2/README.txt @@ -0,0 +1,19 @@ +== Simple Amplifier == + +This plugin is a simple example of a basic LV2 plugin with no additional features. +It has audio ports which contain an array of `float`, +and a control port which contains a single `float`. + +LV2 plugins are defined in two parts: code and data. +The code is written in C, or any C compatible language such as C++. +Static data is described separately in the human and machine friendly http://www.w3.org/TeamSubmission/turtle/[Turtle] syntax. + +Generally, the goal is to keep code minimal, +and describe as much as possible in the static data. +There are several advantages to this approach: + + * Hosts can discover and inspect plugins without loading or executing any plugin code. + * Plugin data can be used from a wide range of generic tools like scripting languages and command line utilities. + * The standard data model allows the use of existing vocabularies to describe plugins and related information. + * The language is extensible, so authors may describe any data without requiring changes to the LV2 specification. + * Labels and documentation are translatable, and available to hosts for display in user interfaces. diff --git a/plugins/eg-amp.lv2/amp.c b/plugins/eg-amp.lv2/amp.c new file mode 100644 index 0000000..c3ba279 --- /dev/null +++ b/plugins/eg-amp.lv2/amp.c @@ -0,0 +1,230 @@ +/* + Copyright 2006-2016 David Robillard <d@drobilla.net> + Copyright 2006 Steve Harris <steve@plugin.org.uk> + + Permission to use, copy, modify, and/or distribute this software for any + purpose with or without fee is hereby granted, provided that the above + copyright notice and this permission notice appear in all copies. + + THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +*/ + +/** + LV2 headers are based on the URI of the specification they come from, so a + consistent convention can be used even for unofficial extensions. The URI + of the core LV2 specification is <http://lv2plug.in/ns/lv2core>, by + replacing `http:/` with `lv2` any header in the specification bundle can be + included, in this case `lv2.h`. +*/ +#include "lv2/core/lv2.h" + +/** Include standard C headers */ +#include <math.h> +#include <stdint.h> +#include <stdlib.h> + +/** + The URI is the identifier for a plugin, and how the host associates this + implementation in code with its description in data. In this plugin it is + only used once in the code, but defining the plugin URI at the top of the + file is a good convention to follow. If this URI does not match that used + in the data files, the host will fail to load the plugin. +*/ +#define AMP_URI "http://lv2plug.in/plugins/eg-amp" + +/** + In code, ports are referred to by index. An enumeration of port indices + should be defined for readability. +*/ +typedef enum { + AMP_GAIN = 0, + AMP_INPUT = 1, + AMP_OUTPUT = 2 +} PortIndex; + +/** + Every plugin defines a private structure for the plugin instance. All data + associated with a plugin instance is stored here, and is available to + every instance method. In this simple plugin, only port buffers need to be + stored, since there is no additional instance data. +*/ +typedef struct { + // Port buffers + const float* gain; + const float* input; + float* output; +} Amp; + +/** + The `instantiate()` function is called by the host to create a new plugin + instance. The host passes the plugin descriptor, sample rate, and bundle + path for plugins that need to load additional resources (e.g. waveforms). + The features parameter contains host-provided features defined in LV2 + extensions, but this simple plugin does not use any. + + This function is in the ``instantiation'' threading class, so no other + methods on this instance will be called concurrently with it. +*/ +static LV2_Handle +instantiate(const LV2_Descriptor* descriptor, + double rate, + const char* bundle_path, + const LV2_Feature* const* features) +{ + Amp* amp = (Amp*)calloc(1, sizeof(Amp)); + + return (LV2_Handle)amp; +} + +/** + The `connect_port()` method is called by the host to connect a particular + port to a buffer. The plugin must store the data location, but data may not + be accessed except in run(). + + This method is in the ``audio'' threading class, and is called in the same + context as run(). +*/ +static void +connect_port(LV2_Handle instance, + uint32_t port, + void* data) +{ + Amp* amp = (Amp*)instance; + + switch ((PortIndex)port) { + case AMP_GAIN: + amp->gain = (const float*)data; + break; + case AMP_INPUT: + amp->input = (const float*)data; + break; + case AMP_OUTPUT: + amp->output = (float*)data; + break; + } +} + +/** + The `activate()` method is called by the host to initialise and prepare the + plugin instance for running. The plugin must reset all internal state + except for buffer locations set by `connect_port()`. Since this plugin has + no other internal state, this method does nothing. + + This method is in the ``instantiation'' threading class, so no other + methods on this instance will be called concurrently with it. +*/ +static void +activate(LV2_Handle instance) +{ +} + +/** Define a macro for converting a gain in dB to a coefficient. */ +#define DB_CO(g) ((g) > -90.0f ? powf(10.0f, (g) * 0.05f) : 0.0f) + +/** + The `run()` method is the main process function of the plugin. It processes + a block of audio in the audio context. Since this plugin is + `lv2:hardRTCapable`, `run()` must be real-time safe, so blocking (e.g. with + a mutex) or memory allocation are not allowed. +*/ +static void +run(LV2_Handle instance, uint32_t n_samples) +{ + const Amp* amp = (const Amp*)instance; + + const float gain = *(amp->gain); + const float* const input = amp->input; + float* const output = amp->output; + + const float coef = DB_CO(gain); + + for (uint32_t pos = 0; pos < n_samples; pos++) { + output[pos] = input[pos] * coef; + } +} + +/** + The `deactivate()` method is the counterpart to `activate()`, and is called by + the host after running the plugin. It indicates that the host will not call + `run()` again until another call to `activate()` and is mainly useful for more + advanced plugins with ``live'' characteristics such as those with auxiliary + processing threads. As with `activate()`, this plugin has no use for this + information so this method does nothing. + + This method is in the ``instantiation'' threading class, so no other + methods on this instance will be called concurrently with it. +*/ +static void +deactivate(LV2_Handle instance) +{ +} + +/** + Destroy a plugin instance (counterpart to `instantiate()`). + + This method is in the ``instantiation'' threading class, so no other + methods on this instance will be called concurrently with it. +*/ +static void +cleanup(LV2_Handle instance) +{ + free(instance); +} + +/** + The `extension_data()` function returns any extension data supported by the + plugin. Note that this is not an instance method, but a function on the + plugin descriptor. It is usually used by plugins to implement additional + interfaces. This plugin does not have any extension data, so this function + returns NULL. + + This method is in the ``discovery'' threading class, so no other functions + or methods in this plugin library will be called concurrently with it. +*/ +static const void* +extension_data(const char* uri) +{ + return NULL; +} + +/** + Every plugin must define an `LV2_Descriptor`. It is best to define + descriptors statically to avoid leaking memory and non-portable shared + library constructors and destructors to clean up properly. +*/ +static const LV2_Descriptor descriptor = { + AMP_URI, + instantiate, + connect_port, + activate, + run, + deactivate, + cleanup, + extension_data +}; + +/** + The `lv2_descriptor()` function is the entry point to the plugin library. The + host will load the library and call this function repeatedly with increasing + indices to find all the plugins defined in the library. The index is not an + indentifier, the URI of the returned descriptor is used to determine the + identify of the plugin. + + This method is in the ``discovery'' threading class, so no other functions + or methods in this plugin library will be called concurrently with it. +*/ +LV2_SYMBOL_EXPORT +const LV2_Descriptor* +lv2_descriptor(uint32_t index) +{ + switch (index) { + case 0: return &descriptor; + default: return NULL; + } +} diff --git a/plugins/eg-amp.lv2/amp.ttl b/plugins/eg-amp.lv2/amp.ttl new file mode 100644 index 0000000..9f522a1 --- /dev/null +++ b/plugins/eg-amp.lv2/amp.ttl @@ -0,0 +1,90 @@ +# The full description of the plugin is in this file, which is linked to from +# `manifest.ttl`. This is done so the host only needs to scan the relatively +# small `manifest.ttl` files to quickly discover all plugins. + +@prefix doap: <http://usefulinc.com/ns/doap#> . +@prefix lv2: <http://lv2plug.in/ns/lv2core#> . +@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . +@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> . +@prefix units: <http://lv2plug.in/ns/extensions/units#> . + +# First the type of the plugin is described. All plugins must explicitly list +# `lv2:Plugin` as a type. A more specific type should also be given, where +# applicable, so hosts can present a nicer UI for loading plugins. Note that +# this URI is the identifier of the plugin, so if it does not match the one in +# `manifest.ttl`, the host will not discover the plugin data at all. +<http://lv2plug.in/plugins/eg-amp> + a lv2:Plugin , + lv2:AmplifierPlugin ; +# Plugins are associated with a project, where common information like +# developers, home page, and so on are described. This plugin is part of the +# LV2 project, which has URI <http://lv2plug.in/ns/lv2>, and is described +# elsewhere. Typical plugin collections will describe the project in +# manifest.ttl + lv2:project <http://lv2plug.in/ns/lv2> ; +# Every plugin must have a name, described with the doap:name property. +# Translations to various languages can be added by putting a language tag +# after strings as shown. + doap:name "Simple Amplifier" , + "简单放大器"@zh , + "Einfacher Verstärker"@de , + "Simple Amplifier"@en-gb , + "Amplificador Simple"@es , + "Amplificateur de Base"@fr , + "Amplificatore Semplice"@it , + "簡単なアンプ"@jp , + "Просто Усилитель"@ru ; + doap:license <http://opensource.org/licenses/isc> ; + lv2:optionalFeature lv2:hardRTCapable ; + lv2:port [ +# Every port must have at least two types, one that specifies direction +# (lv2:InputPort or lv2:OutputPort), and another to describe the data type. +# This port is a lv2:ControlPort, which means it contains a single float. + a lv2:InputPort , + lv2:ControlPort ; + lv2:index 0 ; + lv2:symbol "gain" ; + lv2:name "Gain" , + "收益"@zh , + "Verstärkung"@de , + "Gain"@en-gb , + "Aumento"@es , + "Gain"@fr , + "Guadagno"@it , + "利益"@jp , + "Увеличение"@ru ; +# An lv2:ControlPort should always describe its default value, and usually a +# minimum and maximum value. Defining a range is not strictly required, but +# should be done wherever possible to aid host support, particularly for UIs. + lv2:default 0.0 ; + lv2:minimum -90.0 ; + lv2:maximum 24.0 ; +# Ports can describe units and control detents to allow better UI generation +# and host automation. + units:unit units:db ; + lv2:scalePoint [ + rdfs:label "+5" ; + rdf:value 5.0 + ] , [ + rdfs:label "0" ; + rdf:value 0.0 + ] , [ + rdfs:label "-5" ; + rdf:value -5.0 + ] , [ + rdfs:label "-10" ; + rdf:value -10.0 + ] + ] , [ + a lv2:AudioPort , + lv2:InputPort ; + lv2:index 1 ; + lv2:symbol "in" ; + lv2:name "In" + ] , [ + a lv2:AudioPort , + lv2:OutputPort ; + lv2:index 2 ; + lv2:symbol "out" ; + lv2:name "Out" + ] . diff --git a/plugins/eg-amp.lv2/manifest.ttl.in b/plugins/eg-amp.lv2/manifest.ttl.in new file mode 100644 index 0000000..4a22f95 --- /dev/null +++ b/plugins/eg-amp.lv2/manifest.ttl.in @@ -0,0 +1,68 @@ +# LV2 plugins are installed in a ``bundle'', a directory with a standard +# structure. Each bundle has a Turtle file named `manifest.ttl` which lists +# the contents of the bundle. +# +# Hosts typically read the manifest of every installed bundle to discover +# plugins on start-up, so it should be as small as possible for performance +# reasons. Details that are only useful if the host chooses to load the plugin +# are stored in other files and linked to from `manifest.ttl`. +# +# ==== URIs ==== +# +# LV2 makes use of URIs as globally-unique identifiers for resources. For +# example, the ID of the plugin described here is +# `<http://lv2plug.in/plugins/eg-amp>`. Note that URIs are only used as +# identifiers and don't necessarily imply that something can be accessed at +# that address on the web (though that may be the case). +# +# ==== Namespace Prefixes ==== +# +# Turtle files contain many URIs, but prefixes can be defined to improve +# readability. For example, with the `lv2:` prefix below, `lv2:Plugin` can be +# written instead of `<http://lv2plug.in/ns/lv2core#Plugin>`. + +@prefix lv2: <http://lv2plug.in/ns/lv2core#> . +@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> . + +# ==== Describing a Plugin ==== + +# Turtle files contain a set of ``statements'' which describe resources. +# This file contains 3 statements: +# [options="header"] +# |================================================================ +# | Subject | Predicate | Object +# | <http://lv2plug.in/plugins/eg-amp> | a | lv2:Plugin +# | <http://lv2plug.in/plugins/eg-amp> | lv2:binary | <amp.so> +# | <http://lv2plug.in/plugins/eg-amp> | rdfs:seeAlso | <amp.ttl> +# |================================================================ + +# Firstly, `<http://lv2plug.in/plugins/eg-amp>` is an LV2 plugin: +<http://lv2plug.in/plugins/eg-amp> a lv2:Plugin . + +# The predicate ```a`'' is a Turtle shorthand for `rdf:type`. + +# The binary of that plugin can be found at `<amp.ext>`: +<http://lv2plug.in/plugins/eg-amp> lv2:binary <amp@LIB_EXT@> . + +# This file is a template; the token `@LIB_EXT@` is replaced by the build +# system with the appropriate extension for the current platform before +# installation. For example, in the output `manifest.ttl`, the binary would be +# listed as `<amp.so>`. Relative URIs in manifests are relative to the bundle +# directory, so this refers to a binary with the given name in the same +# directory as this manifest. + +# Finally, more information about this plugin can be found in `<amp.ttl>`: +<http://lv2plug.in/plugins/eg-amp> rdfs:seeAlso <amp.ttl> . + +# ==== Abbreviation ==== +# +# This file shows these statements individually for instructive purposes, but +# the subject `<http://lv2plug.in/plugins/eg-amp>` is repetitive. Turtle +# allows the semicolon to be used as a delimiter that repeats the previous +# subject. For example, this manifest would more realistically be written like +# so: + +<http://lv2plug.in/plugins/eg-amp> + a lv2:Plugin ; + lv2:binary <amp@LIB_EXT@> ; + rdfs:seeAlso <amp.ttl> . diff --git a/plugins/eg-amp.lv2/waf b/plugins/eg-amp.lv2/waf new file mode 120000 index 0000000..59a1ac9 --- /dev/null +++ b/plugins/eg-amp.lv2/waf @@ -0,0 +1 @@ +../../waf
\ No newline at end of file diff --git a/plugins/eg-amp.lv2/wscript b/plugins/eg-amp.lv2/wscript new file mode 100644 index 0000000..6e44f08 --- /dev/null +++ b/plugins/eg-amp.lv2/wscript @@ -0,0 +1,56 @@ +#!/usr/bin/env python +from waflib.extras import autowaf as autowaf +import re + +# Variables for 'waf dist' +APPNAME = 'eg-amp.lv2' +VERSION = '1.0.0' + +# Mandatory variables +top = '.' +out = 'build' + +def options(opt): + opt.load('compiler_c') + opt.load('lv2') + autowaf.set_options(opt) + +def configure(conf): + conf.load('compiler_c', cache=True) + conf.load('lv2', cache=True) + conf.load('autowaf', cache=True) + + autowaf.check_pkg(conf, 'lv2', uselib_store='LV2') + + conf.check(features='c cshlib', lib='m', uselib_store='M', mandatory=False) + +def build(bld): + bundle = 'eg-amp.lv2' + + # Make a pattern for shared objects without the 'lib' prefix + module_pat = re.sub('^lib', '', bld.env.cshlib_PATTERN) + module_ext = module_pat[module_pat.rfind('.'):] + + # Build manifest.ttl by substitution (for portable lib extension) + bld(features = 'subst', + source = 'manifest.ttl.in', + target = '%s/%s' % (bundle, 'manifest.ttl'), + install_path = '${LV2DIR}/%s' % bundle, + LIB_EXT = module_ext) + + # Copy other data files to build bundle (build/eg-amp.lv2) + for i in ['amp.ttl']: + bld(features = 'subst', + is_copy = True, + source = i, + target = '%s/%s' % (bundle, i), + install_path = '${LV2DIR}/%s' % bundle) + + # Build plugin library + obj = bld(features = 'c cshlib', + source = 'amp.c', + name = 'amp', + target = '%s/amp' % bundle, + install_path = '${LV2DIR}/%s' % bundle, + uselib = 'M LV2') + obj.env.cshlib_PATTERN = module_pat |