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Diffstat (limited to 'lv2/core/lv2core.meta.ttl')
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diff --git a/lv2/core/lv2core.meta.ttl b/lv2/core/lv2core.meta.ttl deleted file mode 100644 index 9faea9d..0000000 --- a/lv2/core/lv2core.meta.ttl +++ /dev/null @@ -1,915 +0,0 @@ -@prefix lv2: <http://lv2plug.in/ns/lv2core#> . -@prefix dcs: <http://ontologi.es/doap-changeset#> . -@prefix doap: <http://usefulinc.com/ns/doap#> . -@prefix foaf: <http://xmlns.com/foaf/0.1/> . -@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> . - -<http://lv2plug.in/ns/lv2core> - a doap:Project ; - doap:license <http://opensource.org/licenses/isc> ; - doap:name "LV2" ; - doap:homepage <http://lv2plug.in> ; - doap:created "2004-04-21" ; - doap:shortdesc "An extensible open standard for audio plugins" ; - doap:programming-language "C" ; - doap:developer <http://plugin.org.uk/swh.xrdf#me> , - <http://drobilla.net/drobilla#me> ; - doap:maintainer <http://drobilla.net/drobilla#me> ; - doap:release [ - doap:revision "18.4" ; - doap:created "2022-05-26" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.18.4.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Fix spelling errors." - ] - ] - ] , [ - doap:revision "18.0" ; - doap:created "2020-04-26" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.18.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Add lv2:Markdown datatype." - ] , [ - rdfs:label "Deprecate lv2:reportsLatency." - ] - ] - ] , [ - doap:revision "16.0" ; - doap:created "2019-02-03" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.16.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Add lv2:MIDIPlugin class." - ] , [ - rdfs:label "Rework port restrictions so that presets can be validated." - ] - ] - ] , [ - doap:revision "14.0" ; - doap:created "2016-09-18" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.14.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Add lv2_util.h with lv2_features_data() and lv2_features_query()." - ] , [ - rdfs:label "Add lv2:enabled designation." - ] - ] - ] , [ - doap:revision "12.4" ; - doap:created "2015-04-07" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.12.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Relax domain of lv2:minimum lv2:maximum and lv2:default so they can be used to describe properties/parameters as well." - ] , [ - rdfs:label "Add extern C and visibility attribute to LV2_SYMBOL_EXPORT." - ] , [ - rdfs:label "Add lv2:isSideChain port property." - ] - ] - ] , [ - doap:revision "12.2" ; - doap:created "2014-08-08" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.10.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Clarify lv2_descriptor() and lv2_lib_descriptor() documentation." - ] - ] - ] , [ - doap:revision "12.0" ; - doap:created "2014-01-04" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.8.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Add lv2:prototype for property inheritance." - ] - ] - ] , [ - doap:revision "10.0" ; - doap:created "2013-02-17" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.4.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Add lv2:EnvelopePlugin class." - ] , [ - rdfs:label "Add lv2:control for designating primary event-based control ports." - ] , [ - rdfs:label "Set range of lv2:designation to lv2:Designation." - ] , [ - rdfs:label "Make lv2:Parameter rdfs:subClassOf rdf:Property." - ] , [ - rdfs:label "Reserve minor version 0 for unstable development plugins." - ] - ] - ] , [ - doap:revision "8.2" ; - doap:created "2012-10-14" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.2.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Use consistent label style." - ] - ] - ] , [ - doap:revision "8.0" ; - doap:created "2012-04-17" ; - doap:file-release <http://lv2plug.in/spec/lv2-1.0.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Fix LV2_SYMBOL_EXPORT and lv2_descriptor prototype for Windows." - ] , [ - rdfs:label "Add metadata concept of a designation, a channel or parameter description which can be assigned to ports for more intelligent use by hosts." - ] , [ - rdfs:label "Add new discovery API which allows libraries to read bundle files during discovery, makes library construction/destruction explicit, and adds extensibility to prevent future breakage." - ] , [ - rdfs:label "Relax the range of lv2:index so it can be used for things other than ports." - ] , [ - rdfs:label "Remove lv2:Resource, which turned out to be meaningless." - ] , [ - rdfs:label "Add lv2:CVPort." - ] , [ - rdfs:label "Merge with unified LV2 package." - ] - ] - ] , [ - doap:revision "6.0" ; - doap:created "2011-11-21" ; - doap:file-release <http://lv2plug.in/spec/lv2core-6.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Rename core.lv2 and lv2.ttl to lv2core.lv2 and lv2core.ttl to adhere to modern conventions." - ] , [ - rdfs:label "Add lv2:extensionData and lv2:ExtensionData for plugins to indicate that they support some URI for extension_data()." - ] , [ - rdfs:label "Remove lv2config in favour of the simple convention that specifications install headers to standard URI-based paths." - ] , [ - rdfs:label "Switch to the ISC license, a simple BSD-style license (with permission of all contributors to lv2.h and its ancestor, ladspa.h)." - ] , [ - rdfs:label "Make lv2core.ttl a valid OWL 2 DL ontology." - ] , [ - rdfs:label "Improve documentation." - ] - ] - ] , [ - doap:revision "4.0" ; - doap:created "2011-03-18" ; - doap:file-release <http://lv2plug.in/spec/lv2core-4.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Make doap:license suggested, but not required (for wrappers)." - ] , [ - rdfs:label "Define lv2:binary (MUST be in manifest.ttl)." - ] , [ - rdfs:label "Define lv2:minorVersion and lv2:microVersion (MUST be in manifest.ttl)." - ] , [ - rdfs:label "Define lv2:documentation and use it to document lv2core." - ] , [ - rdfs:label "Add lv2:FunctionPlugin and lv2:ConstantPlugin classes." - ] , [ - rdfs:label "Move lv2:AmplifierPlugin under lv2:DynamicsPlugin." - ] , [ - rdfs:label "Loosen domain of lv2:optionalFeature and lv2:requiredFeature (to allow re-use in extensions)." - ] , [ - rdfs:label "Add generic lv2:Resource and lv2:PluginBase classes." - ] , [ - rdfs:label "Fix definition of lv2:minimum etc. (used for values, not scale points)." - ] , [ - rdfs:label "More precisely define properties with OWL." - ] , [ - rdfs:label "Move project metadata to manifest." - ] , [ - rdfs:label "Add lv2:enumeration port property." - ] , [ - rdfs:label "Define run() pre-roll special case (sample_count == 0)." - ] - ] - ] , [ - doap:revision "3.0" ; - doap:created "2008-11-08" ; - doap:file-release <http://lv2plug.in/spec/lv2core-3.0.tar.bz2> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Require that serialisations refer to ports by symbol rather than index." - ] , [ - rdfs:label "Minor stylistic changes to lv2.ttl." - ] , [ - rdfs:label "No header changes." - ] - ] - ] , [ - doap:revision "2.0" ; - doap:created "2008-02-10" ; - doap:file-release <http://lv2plug.in/spec/lv2core-2.0.tar.gz> ; - dcs:blame <http://drobilla.net/drobilla#me> ; - dcs:changeset [ - dcs:item [ - rdfs:label "Initial release." - ] - ] - ] ; - lv2:documentation """ - -LV2 is an interface for writing audio plugins in C or compatible languages, -which can be dynamically loaded into many _host_ applications. This core -specification is simple and minimal, but is designed so that _extensions_ can -be defined to add more advanced features, making it possible to implement -nearly any feature. - -LV2 maintains a strong distinction between code and data. Plugin code is in a -shared library, while data is in a companion data file written in -[Turtle](https://www.w3.org/TR/turtle/). Code, data, and any other resources -(such as waveforms) are shipped together in a bundle directory. The code -contains only the executable portions of the plugin. All other data is -provided in the data file(s). This makes plugin data flexible and extensible, -and allows the host to do everything but run the plugin without loading or -executing any code. Among other advantages, this makes hosts more robust -(broken plugins can't crash a host during discovery) and allows generic tools -written in any language to work with LV2 data. The LV2 specification itself is -distributed in a similar way. - -An LV2 plugin library is suitable for dynamic loading (for example with -`dlopen()`) and provides one or more plugin descriptors via `lv2_descriptor()` -or `lv2_lib_descriptor()`. These can be instantiated to create plugin -instances, which can be run directly on data or connected together to perform -advanced signal processing tasks. - -Plugins communicate via _ports_, which can transmit any type of data. Data is -processed by first connecting each port to a buffer, then repeatedly calling -the `run()` method to process blocks of data. - -This core specification defines two types of port, equivalent to those in -[LADSPA](http://www.ladspa.org/), lv2:ControlPort and lv2:AudioPort, as well as -lv2:CVPort which has the same format as an audio port but is interpreted as -non-audible control data. Audio ports contain arrays with one `float` element -per sample, allowing a block of audio to be processed in a single call to -`run()`. Control ports contain single `float` values, which are fixed and -valid for the duration of the call to `run()`. Thus the _control rate_ is -determined by the block size, which is controlled by the host (and not -necessarily constant). - -### Threading Rules - -To facilitate use in multi-threaded programs, LV2 functions are partitioned into -several threading classes: - -| Discovery Class | Instantiation Class | Audio Class | -|----------------------------------|-------------------------------|------------------------------- | -| lv2_descriptor() | LV2_Descriptor::instantiate() | LV2_Descriptor::run() | -| lv2_lib_descriptor() | LV2_Descriptor::cleanup() | LV2_Descriptor::connect_port() | -| LV2_Descriptor::extension_data() | LV2_Descriptor::activate() | | -| | LV2_Descriptor::deactivate() | | - -Hosts MUST guarantee that: - - * A function in any class is never called concurrently with another function - in that class. - - * A _Discovery_ function is never called concurrently with any other function - in the same shared object file. - - * An _Instantiation_ function for an instance is never called concurrently - with any other function for that instance. - -Any simultaneous calls that are not explicitly forbidden by these rules are -allowed. For example, a host may call `run()` for two different plugin -instances simultaneously. - -Plugin functions in any class MUST NOT manipulate any state which might affect -other plugins or the host (beyond the contract of that function), for example -by using non-reentrant global functions. - -Extensions to this specification which add new functions MUST declare in which -of these classes the functions belong, define new classes for them, or -otherwise precisely describe their threading rules. - -"""^^lv2:Markdown . - -lv2:Specification - lv2:documentation """ - -An LV2 specification typically contains a vocabulary description, C headers to -define an API, and any other resources that may be useful. Specifications, -like plugins, are distributed and installed as bundles so that hosts may -discover them. - -"""^^lv2:Markdown . - -lv2:Markdown - lv2:documentation """ - -This datatype is typically used for documentation in -[Markdown](https://daringfireball.net/projects/markdown/syntax) syntax. - -Generally, documentation with this datatype should stay as close to readable -plain text as possible, but may use core Markdown syntax for nicer -presentation. Documentation can assume that basic extensions like codehilite -and tables are available. - -"""^^lv2:Markdown . - -lv2:documentation - lv2:documentation """ - -Relates a Resource to extended documentation. - -LV2 specifications are documented using this property with an lv2:Markdown -datatype. - -If the value has no explicit datatype, it is assumed to be a valid XHTML Basic -1.1 fragment suitable for use as the content of the `body` element of a page. - -XHTML Basic is a W3C Recommendation which defines a simplified subset of XHTML -intended to be reasonable to implement with limited resources, for exampe on -embedded devices. See [XHTML Basic, Section -3](http://www.w3.org/TR/xhtml-basic/#s_xhtmlmodules) for a list of valid tags. - -"""^^lv2:Markdown . - -lv2:PluginBase - lv2:documentation """ - -An abstract plugin-like resource that may not actually be an LV2 plugin, for -example that may not have a lv2:binary. This is useful for describing things -that share common structure with a plugin, but are not themselves an actual -plugin, such as presets. - -"""^^lv2:Markdown . - -lv2:Plugin - lv2:documentation """ - -To be discovered by hosts, plugins MUST explicitly have an rdf:type of lv2:Plugin -in their bundle's manifest, for example: - - :::turtle - <http://example.org/my-plugin> a lv2:Plugin . - -Plugins should have a doap:name property that is at most a few words in length -using title capitalization, for example <q>Tape Delay Unit</q>. - -"""^^lv2:Markdown . - -lv2:PortBase - lv2:documentation """ - -Similar to lv2:PluginBase, this is an abstract port-like resource that may not -be a fully specified LV2 port. For example, this is used for preset "ports" -which do not specify an index. - -"""^^lv2:Markdown . - -lv2:Port - lv2:documentation """ - -All LV2 port descriptions MUST have a rdf:type that is one of lv2:Port, -lv2:InputPort or lv2:OutputPort. Additionally, there MUST be at least one -other rdf:type which more precisely describes type of the port, for example -lv2:AudioPort. - -Hosts that do not support a specific port class MUST NOT instantiate the -plugin, unless that port has the lv2:connectionOptional property set. - -A port has two identifiers: a (numeric) index, and a (textual) symbol. The -index can be used as an identifier at run-time, but persistent references to -ports (for example in presets or save files) MUST use the symbol. Only the -symbol is guaranteed to refer to the same port on all plugins with a given URI, -that is the index for a port may differ between plugin binaries. - -"""^^lv2:Markdown . - -lv2:AudioPort - lv2:documentation """ - -Ports of this type are connected to a buffer of `float` audio samples, which -the host guarantees have `sample_count` elements in any call to -LV2_Descriptor::run(). - -Audio samples are normalized between -1.0 and 1.0, though there is no -requirement for samples to be strictly within this range. - -"""^^lv2:Markdown . - -lv2:CVPort - lv2:documentation """ - -Ports of this type have the same buffer format as an lv2:AudioPort, except the -buffer represents audio-rate control data rather than audio. Like a -lv2:ControlPort, a CV port SHOULD have properties describing its value, in -particular lv2:minimum, lv2:maximum, and lv2:default. - -Hosts may present CV ports to users as controls in the same way as control -ports. Conceptually, aside from the buffer format, a CV port is the same as a -control port, so hosts can use all the same properties and expectations. - -In particular, this port type does not imply any range, unit, or meaning for -its values. However, if there is no inherent unit to the values, for example -if the port is used to modulate some other value, then plugins SHOULD use a -normalized range, either from -1.0 to 1.0, or from 0.0 to 1.0. - -It is generally safe to connect an audio output to a CV input, but not -vice-versa. Hosts must take care to prevent data from a CVPort port from being -used as audio. - -"""^^lv2:Markdown . - -lv2:project - lv2:documentation """ - -This property provides a way to group plugins and/or related resources. A -project may have useful metadata common to all plugins (such as homepage, -author, version history) which would be wasteful to list separately for each -plugin. - -Grouping via projects also allows users to find plugins in hosts by project, -which is often how they are remembered. For this reason, a project that -contains plugins SHOULD always have a doap:name. It is also a good idea for -each plugin and the project itself to have an lv2:symbol property, which allows -nice quasi-global identifiers for plugins, for example `myproj.superamp` which -can be useful for display or fast user entry. - -"""^^lv2:Markdown . - -lv2:prototype - lv2:documentation """ - -This property can be used to <q>include</q> common properties in several -descriptions, serving as a sort of template mechanism. If a plugin has a -prototype, then the host must load all the properties for the prototype as if -they were properties of the plugin. That is, if `:plug lv2:prototype :prot`, -then for each triple `:prot p o`, the triple `:plug p o` should be loaded. - -This facility is useful for distributing data-only plugins that rely on a -common binary, for example those where the internal state is loaded from some -other file. Such plugins can refer to a prototype in a template LV2 bundle -which is installed by the corresponding software. - -"""^^lv2:Markdown . - -lv2:minorVersion - lv2:documentation """ - -This, along with lv2:microVersion, is used to distinguish between different -versions of the <q>same</q> resource, for example to load only the bundle with -the most recent version of a plugin. An LV2 version has a minor and micro -number with the usual semantics: - - * The minor version MUST be incremented when backwards (but not forwards) - compatible additions are made, for example the addition of a port to a - plugin. - - * The micro version is incremented for changes which do not affect - compatibility at all, for example bug fixes or documentation updates. - -Note that there is deliberately no major version: all versions with the same -URI are compatible by definition. Replacing a resource with a newer version of -that resource MUST NOT break anything. If a change violates this rule, then -the URI of the resource (which serves as the major version) MUST be changed. - -Plugins and extensions MUST adhere to at least the following rules: - - * All versions of a plugin with a given URI MUST have the <q>same</q> set of - mandatory (not lv2:connectionOptional) ports with respect to lv2:symbol and - rdf:type. In other words, every port on a particular version is guaranteed - to exist on a future version with same lv2:symbol and at least those - rdf:types. - - * New ports MAY be added without changing the plugin URI if and only if they - are lv2:connectionOptional and the minor version is incremented. - - * The minor version MUST be incremented if the index of any port (identified - by its symbol) is changed. - - * All versions of a specification MUST be compatible in the sense that an - implementation of the new version can interoperate with an implementation - of any previous version. - -Anything that depends on a specific version of a plugin (including referencing -ports by index) MUST refer to the plugin by both URI and version. However, -implementations should be tolerant where possible. - -When hosts discover several installed versions of a resource, they SHOULD warn -the user and load only the most recent version. - -An odd minor _or_ micro version, or minor version zero, indicates that the -resource is a development version. Hosts and tools SHOULD clearly indicate -this wherever appropriate. Minor version zero is a special case for -pre-release development of plugins, or experimental plugins that are not -intended for stable use at all. Hosts SHOULD NOT expect such a plugin to -remain compatible with any future version. Where feasible, hosts SHOULD NOT -expose such plugins to users by default, but may provide an option to display -them. - -"""^^lv2:Markdown . - -lv2:microVersion - lv2:documentation """ - -Releases of plugins and extensions MUST be explicitly versioned. Correct -version numbers MUST always be maintained for any versioned resource that is -published. For example, after a release, if a change is made in the development -version in source control, the micro version MUST be incremented (to an odd -number) to distinguish this modified version from the previous release. - -This property describes half of a resource version. For detailed documentation -on LV2 resource versioning, see lv2:minorVersion. - -"""^^lv2:Markdown . - -lv2:binary - lv2:documentation """ - -The value of this property must be the URI of a shared library object, -typically in the same bundle as the data file which contains this property. -The actual type of the library is platform specific. - -This is a required property of a lv2:Plugin which MUST be included in the -bundle's `manifest.ttl` file. The lv2:binary of a lv2:Plugin is the shared -object containing the lv2_descriptor() or lv2_lib_descriptor() function. This -probably may also be used similarly by extensions to relate other resources to -their implementations (it is not implied that a lv2:binary on an arbitrary -resource is an LV2 plugin library). - -"""^^lv2:Markdown . - -lv2:appliesTo - lv2:documentation """ - -This is primarily intended for discovery purposes: bundles that describe -resources that work with particular plugins (like presets or user interfaces) -SHOULD specify this in their `manifest.ttl` so the host can associate them with -the correct plugin. For example: - - :::turtle - <thing> - a ext:Thing ; - lv2:appliesTo <plugin> ; - rdfs:seeAlso <thing.ttl> . - -Using this pattern is preferable for large amounts of data, since the host may -choose whether/when to load the data. - -"""^^lv2:Markdown . - -lv2:Symbol - lv2:documentation """ - -The first character of a symbol must be one of `_`, `a-z` or `A-Z`, and -subsequent characters may additionally be `0-9`. This is, among other things, -a valid C identifier, and generally compatible in most contexts which have -restrictions on string identifiers, such as file paths. - -"""^^lv2:Markdown . - -lv2:symbol - lv2:documentation """ - -The value of this property MUST be a valid lv2:Symbol, and MUST NOT have a -language tag. - -A symbol is a unique identifier with respect to the parent, for example a -port's symbol is a unique identifiers with respect to its plugin. The plugin -author MUST change the plugin URI if any port symbol is changed or removed. - -"""^^lv2:Markdown . - -lv2:name - lv2:documentation """ - -Unlike lv2:symbol, this is unrestricted, may be translated, and is not relevant -for compatibility. The name is not necessarily unique and MUST NOT be used as -an identifier. - -"""^^lv2:Markdown . - -lv2:shortName - lv2:documentation """ - -This is the same as lv2:name, with the additional requirement that the value is -shorter than 16 characters. - -"""^^lv2:Markdown . - -lv2:Designation - lv2:documentation """ - -A designation is metadata that describes the meaning or role of something. By -assigning a designation to a port using lv2:designation, the port's content -becomes meaningful and can be used more intelligently by the host. - -"""^^lv2:Markdown . - -lv2:Channel - lv2:documentation """ - -A specific channel, for example the <q>left</q> channel of a stereo stream. A -channel may be audio, or another type such as a MIDI control stream. - -"""^^lv2:Markdown . - -lv2:Parameter - lv2:documentation """ - -A parameter is a designation for a control. - -A parameter defines the meaning of a control, not the method of conveying its -value. For example, a parameter could be controlled via a lv2:ControlPort, -messages, or both. - -A lv2:ControlPort can be associated with a parameter using lv2:designation. - -"""^^lv2:Markdown . - -lv2:designation - lv2:documentation """ - -This property is used to give a port's contents a well-defined meaning. For -example, if a port has the designation `eg:gain`, then the value of that port -represents the `eg:gain` of the plugin instance. - -Ports should be given designations whenever possible, particularly if a -suitable designation is already defined. This allows the host to act more -intelligently and provide a more effective user interface. For example, if the -plugin has a BPM parameter, the host may automatically set that parameter to -the current tempo. - -"""^^lv2:Markdown . - -lv2:freeWheeling - lv2:documentation """ - -If true, this means that all processing is happening as quickly as possible, -not in real-time. When free-wheeling there is no relationship between the -passage of real wall-clock time and the passage of time in the data being -processed. - -"""^^lv2:Markdown . - -lv2:enabled - lv2:documentation """ - -If this value is greater than zero, the plugin processes normally. If this -value is zero, the plugin is expected to bypass all signals unmodified. The -plugin must provide a click-free transition between the enabled and disabled -(bypassed) states. - -Values less than zero are reserved for future use (such as click-free -insertion/removal of latent plugins), and should be treated like zero -(bypassed) by current implementations. - -"""^^lv2:Markdown . - -lv2:control - lv2:documentation """ - -This should be used as the lv2:designation of ports that are used to send -commands and receive responses. Typically this will be an event port that -supports some protocol, for example MIDI or LV2 Atoms. - -"""^^lv2:Markdown . - -lv2:Point - lv2:documentation """ - - * A Point MUST have at least one rdfs:label which is a string. - - * A Point MUST have exactly one rdf:value with a type that is compatible with - the type of the corresponding Port. - -"""^^lv2:Markdown . - -lv2:default - lv2:documentation """ - -The host SHOULD set the port to this value initially, and in any situation -where the port value should be cleared or reset. - -"""^^lv2:Markdown . - -lv2:minimum - lv2:documentation """ - -This is a soft limit: the plugin is required to gracefully accept all values in -the range of a port's data type. - -"""^^lv2:Markdown . - -lv2:maximum - lv2:documentation """ - -This is a soft limit: the plugin is required to gracefully accept all values in -the range of a port's data type. - -"""^^lv2:Markdown . - -lv2:optionalFeature - lv2:documentation """ - -To support this feature, the host MUST pass its URI and any additional data to -the plugin in LV2_Descriptor::instantiate(). - -The plugin MUST NOT fail to instantiate if an optional feature is not supported -by the host. - -"""^^lv2:Markdown . - -lv2:requiredFeature - lv2:documentation """ - -To support this feature, the host MUST pass its URI and any additional data to -the plugin in LV2_Descriptor::instantiate(). - -The host MUST check this property before attempting to instantiate a plugin, -and not attempt to instantiate plugins which require features it does not -support. The plugin MUST fail to instantiate if a required feature is not -supported by the host. Note that these rules are intentionally redundant for -resilience: neither host nor plugin should assume that the other does not -violate them. - -"""^^lv2:Markdown . - -lv2:ExtensionData - lv2:documentation """ - -This is additional data that a plugin may return from -LV2_Descriptor::extension_data(). This is generally used to add APIs to extend -that defined by LV2_Descriptor. - -"""^^lv2:Markdown . - -lv2:extensionData - lv2:documentation """ - -If a plugin has a value for this property, it must be a URI that defines the -extension data. The plugin should return the appropriate data when -LV2_Descriptor::extension_data() is called with that URI as a parameter. - -"""^^lv2:Markdown . - -lv2:isLive - lv2:documentation """ - -This feature is for plugins that have time-sensitive internals, for example -communicating in real time over a socket. It indicates to the host that its -input and output must not be cached or subject to significant latency, and that -calls to LV2_Descriptor::run() should be made at a rate that roughly -corresponds to wall clock time (according to the `sample_count` parameter). - -Note that this feature is not related to <q>hard real-time</q> execution -requirements (see lv2:hardRTCapable). - -"""^^lv2:Markdown . - -lv2:inPlaceBroken - lv2:documentation """ - -This feature indicates that the plugin may not work correctly if the host -elects to use the same data location for both input and output. Plugins that -will fail to work correctly if ANY input port is connected to the same location -as ANY output port MUST require this feature. Doing so should be avoided -whenever possible since it prevents hosts from running the plugin on data -<q>in-place</q>. - -"""^^lv2:Markdown . - -lv2:hardRTCapable - lv2:documentation """ - -This feature indicates that the plugin is capable of running in a <q>hard -real-time</q> environment. This should be the case for most audio processors, -so most plugins are expected to have this feature. - -To support this feature, plugins MUST adhere to the following in all of their -audio class functions (LV2_Descriptor::run() and -LV2_Descriptor::connect_port()): - - * There is no use of `malloc()`, `free()` or any other heap memory management - functions. - - * There is no use of any library functions which do not adhere to these - rules. The plugin may assume that the standard C math library functions - are safe. - - * There is no access to files, devices, pipes, sockets, system calls, or any - other mechanism that might result in the process or thread blocking. - - * The maximum amount of time for a `run()` call is bounded by some expression - of the form `A + B * sample_count`, where `A` and `B` are platform specific - constants. Note that this bound does not depend on input signals or plugin - state. - -"""^^lv2:Markdown . - -lv2:portProperty - lv2:documentation """ - -States that a port has a particular lv2:PortProperty. This may be ignored -without catastrophic effects, though it may be useful, for example to provide a -sensible user interface for the port. - -"""^^lv2:Markdown . - -lv2:connectionOptional - lv2:documentation """ - -This property means that the port does not have to be connected to valid data -by the host. To leave a port <q>unconnected</q>, the host MUST explicitly -connect the port to `NULL`. - -"""^^lv2:Markdown . - -lv2:reportsLatency - lv2:documentation """ - -This property indicates that the port is used to express the processing latency -incurred by the plugin, expressed in samples. The latency may be affected by -the current sample rate, plugin settings, or other factors, and may be changed -by the plugin at any time. Where the latency is frequency dependent the plugin -may choose any appropriate value. If a plugin introduces latency it MUST -provide EXACTLY ONE port with this property set. In <q>fuzzy</q> cases the -value should be the most reasonable one based on user expectation of -input/output alignment. For example, musical delay plugins should not report -their delay as latency, since it is an intentional effect that the host should -not compensate for. - -This property is deprecated, use a lv2:designation of lv2:latency instead, -following the same rules as above: - - :::turtle - <http://example.org/plugin> - lv2:port [ - a lv2:OutputPort , lv2:ControlPort ; - lv2:designation lv2:latency ; - lv2:symbol "latency" ; - ] - -"""^^lv2:Markdown . - -lv2:toggled - lv2:documentation """ - -Indicates that the data item should be considered a boolean toggle. Data less -than or equal to zero should be considered <q>off</q> or <q>false</q>, and data -above zero should be considered <q>on</q> or <q>true</q>. - -"""^^lv2:Markdown . - -lv2:sampleRate - lv2:documentation """ - -Indicates that any specified bounds should be interpreted as multiples of the -sample rate. For example, a frequency range from 0 Hz to the Nyquist frequency -(half the sample rate) can be specified by using this property with lv2:minimum -0.0 and lv2:maximum 0.5. Hosts that support bounds at all MUST support this -property. - -"""^^lv2:Markdown . - -lv2:integer - lv2:documentation """ - -Indicates that all the reasonable values for a port are integers. For such -ports, a user interface should provide a stepped control that only allows -choosing integer values. - -Note that this is only a hint, and that the plugin MUST operate reasonably even -if such a port has a non-integer value. - -"""^^lv2:Markdown . - -lv2:enumeration - lv2:documentation """ - -Indicates that all the rasonable values for a port are defined by -lv2:scalePoint properties. For such ports, a user interface should provide a selector that allows the user to choose any of the scale point values by name. It is recommended to show the value as well if possible. - -Note that this is only a hint, and that the plugin MUST operate reasonably even -if such a port has a value that does not correspond to a scale point. - -"""^^lv2:Markdown . - -lv2:isSideChain - lv2:documentation """ - -Indicates that a port is a <q>sidechain</q>, which affects the output somehow -but should not be considered a part of the main signal chain. Sidechain ports -SHOULD be lv2:connectionOptional, and may be ignored by hosts. - -"""^^lv2:Markdown . - |