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-rw-r--r--plugins/eg-params.lv2/README.txt21
-rw-r--r--plugins/eg-params.lv2/manifest.ttl.in7
-rw-r--r--plugins/eg-params.lv2/params.c526
-rw-r--r--plugins/eg-params.lv2/params.ttl126
-rw-r--r--plugins/eg-params.lv2/state_map.h110
-rw-r--r--plugins/eg-params.lv2/wscript65
6 files changed, 855 insertions, 0 deletions
diff --git a/plugins/eg-params.lv2/README.txt b/plugins/eg-params.lv2/README.txt
new file mode 100644
index 0000000..acf90c1
--- /dev/null
+++ b/plugins/eg-params.lv2/README.txt
@@ -0,0 +1,21 @@
+== Params ==
+
+The basic LV2 mechanism for controls is
+http://lv2plug.in/ns/lv2core#ControlPort[lv2:ControlPort], inherited from
+LADSPA. Control ports are problematic because they are not sample accurate,
+support only one type (`float`), and require that plugins poll to know when a
+control has changed.
+
+Parameters can be used instead to address these issues. Parameters can be
+thought of as properties of a plugin instance; they are identified by URI and
+have a value of any type. This deliberately meshes with the concept of plugin
+state defined by the http://lv2plug.in/ns/ext/state[LV2 state extension].
+The state extension allows plugins to save and restore their parameters (along
+with other internal state information, if necessary).
+
+Parameters are accessed and manipulated using messages sent via a sequence
+port. The http://lv2plug.in/ns/ext/patch[LV2 patch extension] defines the
+standard messages for working with parameters. Typically, only two are used
+for simple plugins: http://lv2plug.in/ns/ext/patch#Set[patch:Set] sets a
+parameter to some value, and http://lv2plug.in/ns/ext/patch#Get[patch:Get]
+requests that the plugin send a description of its parameters.
diff --git a/plugins/eg-params.lv2/manifest.ttl.in b/plugins/eg-params.lv2/manifest.ttl.in
new file mode 100644
index 0000000..913de7c
--- /dev/null
+++ b/plugins/eg-params.lv2/manifest.ttl.in
@@ -0,0 +1,7 @@
+@prefix lv2: <http://lv2plug.in/ns/lv2core#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+
+<http://lv2plug.in/plugins/eg-params>
+ a lv2:Plugin ;
+ lv2:binary <params@LIB_EXT@> ;
+ rdfs:seeAlso <params.ttl> .
diff --git a/plugins/eg-params.lv2/params.c b/plugins/eg-params.lv2/params.c
new file mode 100644
index 0000000..3df6652
--- /dev/null
+++ b/plugins/eg-params.lv2/params.c
@@ -0,0 +1,526 @@
+/*
+ LV2 Parameter Example Plugin
+ Copyright 2014-2016 David Robillard <d@drobilla.net>
+
+ 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.
+*/
+
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifndef __cplusplus
+# include <stdbool.h>
+#endif
+
+#include "lv2/lv2plug.in/ns/ext/atom/forge.h"
+#include "lv2/lv2plug.in/ns/ext/atom/util.h"
+#include "lv2/lv2plug.in/ns/ext/log/logger.h"
+#include "lv2/lv2plug.in/ns/ext/midi/midi.h"
+#include "lv2/lv2plug.in/ns/ext/patch/patch.h"
+#include "lv2/lv2plug.in/ns/ext/state/state.h"
+#include "lv2/lv2plug.in/ns/ext/urid/urid.h"
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+#include "lv2/lv2plug.in/ns/lv2core/lv2_util.h"
+
+#include "state_map.h"
+
+#define MAX_STRING 1024
+
+#define EG_PARAMS_URI "http://lv2plug.in/plugins/eg-params"
+
+#define N_PROPS 9
+
+typedef struct {
+ LV2_URID plugin;
+ LV2_URID atom_Path;
+ LV2_URID atom_Sequence;
+ LV2_URID atom_URID;
+ LV2_URID atom_eventTransfer;
+ LV2_URID eg_spring;
+ LV2_URID midi_Event;
+ LV2_URID patch_Get;
+ LV2_URID patch_Set;
+ LV2_URID patch_Put;
+ LV2_URID patch_body;
+ LV2_URID patch_subject;
+ LV2_URID patch_property;
+ LV2_URID patch_value;
+} URIs;
+
+typedef struct {
+ LV2_Atom_Int aint;
+ LV2_Atom_Long along;
+ LV2_Atom_Float afloat;
+ LV2_Atom_Double adouble;
+ LV2_Atom_Bool abool;
+ LV2_Atom astring;
+ char string[MAX_STRING];
+ LV2_Atom apath;
+ char path[MAX_STRING];
+ LV2_Atom_Float lfo;
+ LV2_Atom_Float spring;
+} State;
+
+static inline void
+map_uris(LV2_URID_Map* map, URIs* uris)
+{
+ uris->plugin = map->map(map->handle, EG_PARAMS_URI);
+
+ uris->atom_Path = map->map(map->handle, LV2_ATOM__Path);
+ uris->atom_Sequence = map->map(map->handle, LV2_ATOM__Sequence);
+ uris->atom_URID = map->map(map->handle, LV2_ATOM__URID);
+ uris->atom_eventTransfer = map->map(map->handle, LV2_ATOM__eventTransfer);
+ uris->eg_spring = map->map(map->handle, EG_PARAMS_URI "#spring");
+ uris->midi_Event = map->map(map->handle, LV2_MIDI__MidiEvent);
+ uris->patch_Get = map->map(map->handle, LV2_PATCH__Get);
+ uris->patch_Set = map->map(map->handle, LV2_PATCH__Set);
+ uris->patch_Put = map->map(map->handle, LV2_PATCH__Put);
+ uris->patch_body = map->map(map->handle, LV2_PATCH__body);
+ uris->patch_subject = map->map(map->handle, LV2_PATCH__subject);
+ uris->patch_property = map->map(map->handle, LV2_PATCH__property);
+ uris->patch_value = map->map(map->handle, LV2_PATCH__value);
+}
+
+enum {
+ PARAMS_IN = 0,
+ PARAMS_OUT = 1
+};
+
+typedef struct {
+ // Features
+ LV2_URID_Map* map;
+ LV2_URID_Unmap* unmap;
+ LV2_Log_Logger log;
+
+ // Forge for creating atoms
+ LV2_Atom_Forge forge;
+
+ // Ports
+ const LV2_Atom_Sequence* in_port;
+ LV2_Atom_Sequence* out_port;
+
+ // URIs
+ URIs uris;
+
+ // Plugin state
+ StateMapItem props[N_PROPS];
+ State state;
+
+ // Buffer for making strings from URIDs if unmap is not provided
+ char urid_buf[12];
+} Params;
+
+static void
+connect_port(LV2_Handle instance,
+ uint32_t port,
+ void* data)
+{
+ Params* self = (Params*)instance;
+ switch (port) {
+ case PARAMS_IN:
+ self->in_port = (const LV2_Atom_Sequence*)data;
+ break;
+ case PARAMS_OUT:
+ self->out_port = (LV2_Atom_Sequence*)data;
+ break;
+ default:
+ break;
+ }
+}
+
+static LV2_Handle
+instantiate(const LV2_Descriptor* descriptor,
+ double rate,
+ const char* path,
+ const LV2_Feature* const* features)
+{
+ // Allocate instance
+ Params* self = (Params*)calloc(1, sizeof(Params));
+ if (!self) {
+ return NULL;
+ }
+
+ // Get host features
+ const char* missing = lv2_features_query(
+ features,
+ LV2_LOG__log, &self->log.log, false,
+ LV2_URID__map, &self->map, true,
+ LV2_URID__unmap, &self->unmap, false,
+ NULL);
+ lv2_log_logger_set_map(&self->log, self->map);
+ if (missing) {
+ lv2_log_error(&self->log, "Missing feature <%s>\n", missing);
+ free(self);
+ return NULL;
+ }
+
+ // Map URIs and initialise forge
+ map_uris(self->map, &self->uris);
+ lv2_atom_forge_init(&self->forge, self->map);
+
+ // Initialise state dictionary
+ State* state = &self->state;
+ state_map_init(
+ self->props, self->map, self->map->handle,
+ EG_PARAMS_URI "#int", STATE_MAP_INIT(Int, &state->aint),
+ EG_PARAMS_URI "#long", STATE_MAP_INIT(Long, &state->along),
+ EG_PARAMS_URI "#float", STATE_MAP_INIT(Float, &state->afloat),
+ EG_PARAMS_URI "#double", STATE_MAP_INIT(Double, &state->adouble),
+ EG_PARAMS_URI "#bool", STATE_MAP_INIT(Bool, &state->abool),
+ EG_PARAMS_URI "#string", STATE_MAP_INIT(String, &state->astring),
+ EG_PARAMS_URI "#path", STATE_MAP_INIT(Path, &state->apath),
+ EG_PARAMS_URI "#lfo", STATE_MAP_INIT(Float, &state->lfo),
+ EG_PARAMS_URI "#spring", STATE_MAP_INIT(Float, &state->spring),
+ NULL);
+
+ return (LV2_Handle)self;
+}
+
+static void
+cleanup(LV2_Handle instance)
+{
+ free(instance);
+}
+
+/** Helper function to unmap a URID if possible. */
+static const char*
+unmap(Params* self, LV2_URID urid)
+{
+ if (self->unmap) {
+ return self->unmap->unmap(self->unmap->handle, urid);
+ } else {
+ snprintf(self->urid_buf, sizeof(self->urid_buf), "%u", urid);
+ return self->urid_buf;
+ }
+}
+
+static LV2_State_Status
+check_type(Params* self,
+ LV2_URID key,
+ LV2_URID type,
+ LV2_URID required_type)
+{
+ if (type != required_type) {
+ lv2_log_trace(
+ &self->log, "Bad type <%s> for <%s> (needs <%s>)\n",
+ unmap(self, type),
+ unmap(self, key),
+ unmap(self, required_type));
+ return LV2_STATE_ERR_BAD_TYPE;
+ }
+ return LV2_STATE_SUCCESS;
+}
+
+static LV2_State_Status
+set_parameter(Params* self,
+ LV2_URID key,
+ uint32_t size,
+ LV2_URID type,
+ const void* body,
+ bool from_state)
+{
+ // Look up property in state dictionary
+ const StateMapItem* entry = state_map_find(self->props, N_PROPS, key);
+ if (!entry) {
+ lv2_log_trace(&self->log, "Unknown parameter <%s>\n", unmap(self, key));
+ return LV2_STATE_ERR_NO_PROPERTY;
+ }
+
+ // Ensure given type matches property's type
+ if (check_type(self, key, type, entry->value->type)) {
+ return LV2_STATE_ERR_BAD_TYPE;
+ }
+
+ // Set property value in state dictionary
+ lv2_log_trace(&self->log, "Set <%s>\n", entry->uri);
+ memcpy(entry->value + 1, body, size);
+ entry->value->size = size;
+ return LV2_STATE_SUCCESS;
+}
+
+static const LV2_Atom*
+get_parameter(Params* self, LV2_URID key)
+{
+ const StateMapItem* entry = state_map_find(self->props, N_PROPS, key);
+ if (entry) {
+ lv2_log_trace(&self->log, "Get <%s>\n", entry->uri);
+ return entry->value;
+ }
+
+ lv2_log_trace(&self->log, "Unknown parameter <%s>\n", unmap(self, key));
+ return NULL;
+}
+
+static LV2_State_Status
+write_param_to_forge(LV2_State_Handle handle,
+ uint32_t key,
+ const void* value,
+ size_t size,
+ uint32_t type,
+ uint32_t flags)
+{
+ LV2_Atom_Forge* forge = (LV2_Atom_Forge*)handle;
+
+ if (!lv2_atom_forge_key(forge, key) ||
+ !lv2_atom_forge_atom(forge, size, type) ||
+ !lv2_atom_forge_write(forge, value, size)) {
+ return LV2_STATE_ERR_UNKNOWN;
+ }
+
+ return LV2_STATE_SUCCESS;
+}
+
+static void
+store_prop(Params* self,
+ LV2_State_Map_Path* map_path,
+ LV2_State_Status* save_status,
+ LV2_State_Store_Function store,
+ LV2_State_Handle handle,
+ LV2_URID key,
+ const LV2_Atom* value)
+{
+ LV2_State_Status st;
+ if (map_path && value->type == self->uris.atom_Path) {
+ // Map path to abstract path for portable storage
+ const char* path = (const char*)(value + 1);
+ char* apath = map_path->abstract_path(map_path->handle, path);
+ st = store(handle,
+ key,
+ apath,
+ strlen(apath) + 1,
+ self->uris.atom_Path,
+ LV2_STATE_IS_POD | LV2_STATE_IS_PORTABLE);
+ free(apath);
+ } else {
+ // Store simple property
+ st = store(handle,
+ key,
+ value + 1,
+ value->size,
+ value->type,
+ LV2_STATE_IS_POD | LV2_STATE_IS_PORTABLE);
+ }
+
+ if (save_status && !*save_status) {
+ *save_status = st;
+ }
+}
+
+/**
+ State save method.
+
+ This is used in the usual way when called by the host to save plugin state,
+ but also internally for writing messages in the audio thread by passing a
+ "store" function which actually writes the description to the forge.
+*/
+static LV2_State_Status
+save(LV2_Handle instance,
+ LV2_State_Store_Function store,
+ LV2_State_Handle handle,
+ uint32_t flags,
+ const LV2_Feature* const* features)
+{
+ Params* self = (Params*)instance;
+ LV2_State_Map_Path* map_path = (LV2_State_Map_Path*)lv2_features_data(
+ features, LV2_STATE__mapPath);
+
+ LV2_State_Status st = LV2_STATE_SUCCESS;
+ for (unsigned i = 0; i < N_PROPS; ++i) {
+ StateMapItem* prop = &self->props[i];
+ store_prop(self, map_path, &st, store, handle, prop->urid, prop->value);
+ }
+
+ return st;
+}
+
+static void
+retrieve_prop(Params* self,
+ LV2_State_Status* restore_status,
+ LV2_State_Retrieve_Function retrieve,
+ LV2_State_Handle handle,
+ LV2_URID key)
+{
+ // Retrieve value from saved state
+ size_t vsize;
+ uint32_t vtype;
+ uint32_t vflags;
+ const void* value = retrieve(handle, key, &vsize, &vtype, &vflags);
+
+ // Set plugin instance state
+ const LV2_State_Status st = value
+ ? set_parameter(self, key, vsize, vtype, value, true)
+ : LV2_STATE_ERR_NO_PROPERTY;
+
+ if (!*restore_status) {
+ *restore_status = st; // Set status if there has been no error yet
+ }
+}
+
+/** State restore method. */
+static LV2_State_Status
+restore(LV2_Handle instance,
+ LV2_State_Retrieve_Function retrieve,
+ LV2_State_Handle handle,
+ uint32_t flags,
+ const LV2_Feature* const* features)
+{
+ Params* self = (Params*)instance;
+ LV2_State_Status st = LV2_STATE_SUCCESS;
+
+ for (unsigned i = 0; i < N_PROPS; ++i) {
+ retrieve_prop(self, &st, retrieve, handle, self->props[i].urid);
+ }
+
+ return st;
+}
+
+static inline bool
+subject_is_plugin(Params* self, const LV2_Atom_URID* subject)
+{
+ // This simple plugin only supports one subject: itself
+ return (!subject || (subject->atom.type == self->uris.atom_URID &&
+ subject->body == self->uris.plugin));
+}
+
+static void
+run(LV2_Handle instance, uint32_t sample_count)
+{
+ Params* self = (Params*)instance;
+ URIs* uris = &self->uris;
+
+ // Initially, self->out_port contains a Chunk with size set to capacity
+ // Set up forge to write directly to output port
+ const uint32_t out_capacity = self->out_port->atom.size;
+ lv2_atom_forge_set_buffer(&self->forge,
+ (uint8_t*)self->out_port,
+ out_capacity);
+
+ // Start a sequence in the output port
+ LV2_Atom_Forge_Frame out_frame;
+ lv2_atom_forge_sequence_head(&self->forge, &out_frame, 0);
+
+ // Read incoming events
+ LV2_ATOM_SEQUENCE_FOREACH(self->in_port, ev) {
+ const LV2_Atom_Object* obj = (const LV2_Atom_Object*)&ev->body;
+ if (obj->body.otype == uris->patch_Set) {
+ // Get the property and value of the set message
+ const LV2_Atom_URID* subject = NULL;
+ const LV2_Atom_URID* property = NULL;
+ const LV2_Atom* value = NULL;
+ lv2_atom_object_get(obj,
+ uris->patch_subject, (const LV2_Atom**)&subject,
+ uris->patch_property, (const LV2_Atom**)&property,
+ uris->patch_value, &value,
+ 0);
+ if (!subject_is_plugin(self, subject)) {
+ lv2_log_error(&self->log, "Set for unknown subject\n");
+ } else if (!property) {
+ lv2_log_error(&self->log, "Set with no property\n");
+ } else if (property->atom.type != uris->atom_URID) {
+ lv2_log_error(&self->log, "Set property is not a URID\n");
+ } else {
+ // Set property to the given value
+ const LV2_URID key = property->body;
+ set_parameter(self, key, value->size, value->type, value + 1, false);
+ }
+ } else if (obj->body.otype == uris->patch_Get) {
+ // Get the property of the get message
+ const LV2_Atom_URID* subject = NULL;
+ const LV2_Atom_URID* property = NULL;
+ lv2_atom_object_get(obj,
+ uris->patch_subject, (const LV2_Atom**)&subject,
+ uris->patch_property, (const LV2_Atom**)&property,
+ 0);
+ if (!subject_is_plugin(self, subject)) {
+ lv2_log_error(&self->log, "Get with unknown subject\n");
+ } else if (!property) {
+ // Get with no property, emit complete state
+ lv2_atom_forge_frame_time(&self->forge, ev->time.frames);
+ LV2_Atom_Forge_Frame pframe;
+ lv2_atom_forge_object(&self->forge, &pframe, 0, uris->patch_Put);
+ lv2_atom_forge_key(&self->forge, uris->patch_body);
+
+ LV2_Atom_Forge_Frame bframe;
+ lv2_atom_forge_object(&self->forge, &bframe, 0, 0);
+ save(self, write_param_to_forge, &self->forge, 0, NULL);
+
+ lv2_atom_forge_pop(&self->forge, &bframe);
+ lv2_atom_forge_pop(&self->forge, &pframe);
+ } else if (property->atom.type != uris->atom_URID) {
+ lv2_log_error(&self->log, "Get property is not a URID\n");
+ } else {
+ // Get for a specific property
+ const LV2_URID key = property->body;
+ const LV2_Atom* value = get_parameter(self, key);
+ if (value) {
+ lv2_atom_forge_frame_time(&self->forge, ev->time.frames);
+ LV2_Atom_Forge_Frame frame;
+ lv2_atom_forge_object(&self->forge, &frame, 0, uris->patch_Set);
+ lv2_atom_forge_key(&self->forge, uris->patch_property);
+ lv2_atom_forge_urid(&self->forge, property->body);
+ store_prop(self, NULL, NULL, write_param_to_forge, &self->forge,
+ uris->patch_value, value);
+ lv2_atom_forge_pop(&self->forge, &frame);
+ }
+ }
+ } else {
+ lv2_log_trace(&self->log, "Unknown object type <%s>\n",
+ unmap(self, obj->body.otype));
+ }
+ }
+
+ if (self->state.spring.body > 0.0f) {
+ const float spring = self->state.spring.body;
+ self->state.spring.body = (spring >= 0.001) ? spring - 0.001 : 0.0;
+ lv2_atom_forge_frame_time(&self->forge, 0);
+ LV2_Atom_Forge_Frame frame;
+ lv2_atom_forge_object(&self->forge, &frame, 0, uris->patch_Set);
+
+ lv2_atom_forge_key(&self->forge, uris->patch_property);
+ lv2_atom_forge_urid(&self->forge, uris->eg_spring);
+ lv2_atom_forge_key(&self->forge, uris->patch_value);
+ lv2_atom_forge_float(&self->forge, self->state.spring.body);
+
+ lv2_atom_forge_pop(&self->forge, &frame);
+ }
+
+ lv2_atom_forge_pop(&self->forge, &out_frame);
+}
+
+static const void*
+extension_data(const char* uri)
+{
+ static const LV2_State_Interface state = { save, restore };
+ if (!strcmp(uri, LV2_STATE__interface)) {
+ return &state;
+ }
+ return NULL;
+}
+
+static const LV2_Descriptor descriptor = {
+ EG_PARAMS_URI,
+ instantiate,
+ connect_port,
+ NULL, // activate,
+ run,
+ NULL, // deactivate,
+ cleanup,
+ extension_data
+};
+
+LV2_SYMBOL_EXPORT const LV2_Descriptor*
+lv2_descriptor(uint32_t index)
+{
+ return (index == 0) ? &descriptor : NULL;
+}
diff --git a/plugins/eg-params.lv2/params.ttl b/plugins/eg-params.lv2/params.ttl
new file mode 100644
index 0000000..dbcf6aa
--- /dev/null
+++ b/plugins/eg-params.lv2/params.ttl
@@ -0,0 +1,126 @@
+@prefix atom: <http://lv2plug.in/ns/ext/atom#> .
+@prefix doap: <http://usefulinc.com/ns/doap#> .
+@prefix lv2: <http://lv2plug.in/ns/lv2core#> .
+@prefix param: <http://lv2plug.in/ns/ext/parameters#> .
+@prefix patch: <http://lv2plug.in/ns/ext/patch#> .
+@prefix plug: <http://lv2plug.in/plugins/eg-params#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix state: <http://lv2plug.in/ns/ext/state#> .
+@prefix urid: <http://lv2plug.in/ns/ext/urid#> .
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
+
+# An existing parameter or RDF property can be used as a parameter. The LV2
+# parameters extension <http://lv2plug.in/ns/ext/parameters> defines many
+# common audio parameters. Where possible, existing parameters should be used
+# so hosts can intelligently control plugins.
+
+# If no suitable parameter exists, one can be defined for the plugin like so:
+
+plug:int
+ a lv2:Parameter ;
+ rdfs:label "int" ;
+ rdfs:range atom:Int .
+
+plug:long
+ a lv2:Parameter ;
+ rdfs:label "long" ;
+ rdfs:range atom:Long .
+
+plug:float
+ a lv2:Parameter ;
+ rdfs:label "float" ;
+ rdfs:range atom:Float .
+
+plug:double
+ a lv2:Parameter ;
+ rdfs:label "double" ;
+ rdfs:range atom:Double .
+
+plug:bool
+ a lv2:Parameter ;
+ rdfs:label "bool" ;
+ rdfs:range atom:Bool .
+
+plug:string
+ a lv2:Parameter ;
+ rdfs:label "string" ;
+ rdfs:range atom:String .
+
+plug:path
+ a lv2:Parameter ;
+ rdfs:label "path" ;
+ rdfs:range atom:Path .
+
+plug:lfo
+ a lv2:Parameter ;
+ rdfs:label "LFO" ;
+ rdfs:range atom:Float ;
+ lv2:minimum -1.0 ;
+ lv2:maximum 1.0 .
+
+plug:spring
+ a lv2:Parameter ;
+ rdfs:label "spring" ;
+ rdfs:range atom:Float .
+
+# Most of the plugin description is similar to the others we have seen, but
+# this plugin has only two ports, for receiving and sending messages used to
+# manipulate and access parameters.
+<http://lv2plug.in/plugins/eg-params>
+ a lv2:Plugin ,
+ lv2:UtilityPlugin ;
+ doap:name "Example Parameters" ;
+ doap:license <http://opensource.org/licenses/isc> ;
+ lv2:project <http://lv2plug.in/ns/lv2> ;
+ lv2:requiredFeature urid:map ;
+ lv2:optionalFeature lv2:hardRTCapable ,
+ state:loadDefaultState ;
+ lv2:extensionData state:interface ;
+ lv2:port [
+ a lv2:InputPort ,
+ atom:AtomPort ;
+ atom:bufferType atom:Sequence ;
+ atom:supports patch:Message ;
+ lv2:designation lv2:control ;
+ lv2:index 0 ;
+ lv2:symbol "in" ;
+ lv2:name "In"
+ ] , [
+ a lv2:OutputPort ,
+ atom:AtomPort ;
+ atom:bufferType atom:Sequence ;
+ atom:supports patch:Message ;
+ lv2:designation lv2:control ;
+ lv2:index 1 ;
+ lv2:symbol "out" ;
+ lv2:name "Out"
+ ] ;
+# The plugin must list all parameters that can be written (e.g. changed by the
+# user) as patch:writable:
+ patch:writable plug:int ,
+ plug:long ,
+ plug:float ,
+ plug:double ,
+ plug:bool ,
+ plug:string ,
+ plug:path ,
+ plug:spring ;
+# Similarly, parameters that may change internally must be listed as patch:readable,
+# meaning to host should watch for changes to the parameter's value:
+ patch:readable plug:lfo ,
+ plug:spring ;
+# Parameters map directly to properties of the plugin's state. So, we can
+# specify initial parameter values with the state:state property. The
+# state:loadDefaultState feature (required above) requires that the host loads
+# the default state after instantiation but before running the plugin.
+ state:state [
+ plug:int 0 ;
+ plug:long "0"^^xsd:long ;
+ plug:float 0.1234 ;
+ plug:double "0e0"^^xsd:double ;
+ plug:bool false ;
+ plug:string "Hello, world" ;
+ plug:path <params.ttl> ;
+ plug:spring 0.0 ;
+ plug:lfo 0.0
+ ] .
diff --git a/plugins/eg-params.lv2/state_map.h b/plugins/eg-params.lv2/state_map.h
new file mode 100644
index 0000000..cd97a80
--- /dev/null
+++ b/plugins/eg-params.lv2/state_map.h
@@ -0,0 +1,110 @@
+/*
+ LV2 State Map
+ Copyright 2016 David Robillard <d@drobilla.net>
+
+ 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.
+*/
+
+#include <stdlib.h>
+
+/** Entry in an array that serves as a dictionary of properties. */
+typedef struct {
+ const char* uri;
+ LV2_URID urid;
+ LV2_Atom* value;
+} StateMapItem;
+
+/** Comparator for StateMapItems sorted by URID. */
+static int
+state_map_cmp(const void* a, const void* b)
+{
+ const StateMapItem* ka = (const StateMapItem*)a;
+ const StateMapItem* kb = (const StateMapItem*)b;
+ if (ka->urid < kb->urid) {
+ return -1;
+ } else if (kb->urid < ka->urid) {
+ return 1;
+ }
+ return 0;
+}
+
+/** Helper macro for terse state map initialisation. */
+#define STATE_MAP_INIT(type, ptr) \
+ (LV2_ATOM__ ## type), \
+ (sizeof(*ptr) - sizeof(LV2_Atom)), \
+ (ptr)
+
+/**
+ Initialise a state map.
+
+ The variable parameters list must be NULL terminated, and is a sequence of
+ const char* uri, const char* type, uint32_t size, LV2_Atom* value. The
+ value must point to a valid atom that resides elsewhere, the state map is
+ only an index and does not contain actual state values. The macro
+ STATE_MAP_INIT can be used to make simpler code when state is composed of
+ standard atom types, for example:
+
+ struct Plugin {
+ LV2_URID_Map* map;
+ StateMapItem props[3];
+ // ...
+ };
+
+ state_map_init(
+ self->props, self->map, self->map->handle,
+ PLUG_URI "#gain", STATE_MAP_INIT(Float, &state->gain),
+ PLUG_URI "#offset", STATE_MAP_INIT(Int, &state->offset),
+ PLUG_URI "#file", STATE_MAP_INIT(Path, &state->file),
+ NULL);
+*/
+static void
+state_map_init(StateMapItem dict[],
+ LV2_URID_Map* map,
+ LV2_URID_Map_Handle handle,
+ /* const char* uri, const char* type, uint32_t size, LV2_Atom* value */ ...)
+{
+ // Set dict entries from parameters
+ unsigned i = 0;
+ va_list args;
+ va_start(args, handle);
+ for (const char* uri; (uri = va_arg(args, const char*)); ++i) {
+ const char* type = va_arg(args, const char*);
+ const uint32_t size = va_arg(args, uint32_t);
+ LV2_Atom* const value = va_arg(args, LV2_Atom*);
+ dict[i].uri = uri;
+ dict[i].urid = map->map(map->handle, uri);
+ dict[i].value = value;
+ dict[i].value->size = size;
+ dict[i].value->type = map->map(map->handle, type);
+ }
+ va_end(args);
+
+ // Sort for fast lookup by URID by state_map_find()
+ qsort(dict, i, sizeof(StateMapItem), state_map_cmp);
+}
+
+/**
+ Retrieve an item from a state map by URID.
+
+ This takes O(lg(n)) time, and is useful for implementing generic property
+ access with little code, for example to respond to patch:Get messages for a
+ specific property.
+*/
+static StateMapItem*
+state_map_find(StateMapItem dict[], uint32_t n_entries, LV2_URID urid)
+{
+ const StateMapItem key = { NULL, urid, NULL };
+ return (StateMapItem*)bsearch(
+ &key, dict, n_entries, sizeof(StateMapItem), state_map_cmp);
+}
+
diff --git a/plugins/eg-params.lv2/wscript b/plugins/eg-params.lv2/wscript
new file mode 100644
index 0000000..60dcee4
--- /dev/null
+++ b/plugins/eg-params.lv2/wscript
@@ -0,0 +1,65 @@
+#!/usr/bin/env python
+from waflib.extras import autowaf as autowaf
+import re
+
+# Variables for 'waf dist'
+APPNAME = 'eg-params.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):
+ autowaf.display_header('Params Configuration')
+ conf.load('compiler_c', cache=True)
+ conf.load('lv2', cache=True)
+ conf.load('autowaf', cache=True)
+
+ if not autowaf.is_child():
+ autowaf.check_pkg(conf, 'lv2', atleast_version='1.12.1', uselib_store='LV2')
+
+ autowaf.display_msg(conf, 'LV2 bundle directory', conf.env.LV2DIR)
+ print('')
+
+def build(bld):
+ bundle = 'eg-params.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 = '${LV2DIR}/%s' % bundle,
+ LIB_EXT = module_ext)
+
+ # Copy other data files to build bundle (build/eg-params.lv2)
+ for i in ['params.ttl']:
+ bld(features = 'subst',
+ is_copy = True,
+ source = i,
+ target = '%s/%s' % (bundle, i),
+ install_path = '${LV2DIR}/%s' % bundle)
+
+ # Use LV2 headers from parent directory if building as a sub-project
+ includes = ['.']
+ if autowaf.is_child:
+ includes += ['../..']
+
+ # Build plugin library
+ obj = bld(features = 'c cshlib',
+ source = 'params.c',
+ name = 'params',
+ target = '%s/params' % bundle,
+ install_path = '${LV2DIR}/%s' % bundle,
+ use = 'LV2',
+ includes = includes)
+ obj.env.cshlib_PATTERN = module_pat
generated by cgit v1.2.1 (git 2.18.0) at 2024-11-08 03:25:37 +0000