diff options
Diffstat (limited to 'lv2/lv2.cc')
| -rw-r--r-- | lv2/lv2.cc | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/lv2/lv2.cc b/lv2/lv2.cc new file mode 100644 index 0000000..8a8d7a3 --- /dev/null +++ b/lv2/lv2.cc @@ -0,0 +1,306 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/*************************************************************************** + * lv2.cc + * + * Wed Jul 13 13:50:33 CEST 2011 + * Copyright 2011 Bent Bisballe Nyeng + * deva@aasimon.org + ****************************************************************************/ + +/* + * This file is part of DrumGizmo. + * + * DrumGizmo is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * DrumGizmo is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with DrumGizmo; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ +#include <lv2/lv2plug.in/ns/lv2core/lv2.h> + +#include <stdlib.h> + +#include <drumgizmo.h> + +#include "input_lv2.h" +#include "output_lv2.h" + +#define MIDI_EVENT_URI "http://lv2plug.in/ns/ext/midi#MidiEvent" + +typedef struct { + InputLV2 *in; + OutputLV2 *out; + DrumGizmo *dg; + sample_t *buffer; + size_t buffer_size; +} DGLV2; + +/** A globally unique, case-sensitive identifier for this plugin type. + * + * All plugins with the same URI MUST be compatible in terms of 'port + * signature', meaning they have the same number of ports, same port + * shortnames, and roughly the same functionality. URIs should + * probably contain a version number (or similar) for this reason. + * + * Rationale: When serializing session/patch/etc files, hosts MUST + * refer to a loaded plugin by the plugin URI only. In the future + * loading a plugin with this URI MUST yield a plugin with the + * same ports (etc) which is 100% compatible. */ +#define DRUMGIZMO_URI "http://drumgizmo.org/lv2" + +/** Function pointer that instantiates a plugin. + * + * A handle is returned indicating the new plugin instance. The + * instantiation function accepts a sample rate as a parameter as well + * as the plugin descriptor from which this instantiate function was + * found. This function must return NULL if instantiation fails. + * + * bundle_path is a string of the path to the LV2 bundle which contains + * this plugin binary. It MUST include the trailing directory separator + * (e.g. '/') so that BundlePath + filename gives the path to a file + * in the bundle. + * + * features is a NULL terminated array of LV2_Feature structs which + * represent the features the host supports. Plugins may refuse to + * instantiate if required features are not found here (however hosts + * SHOULD NOT use this as a discovery mechanism, instead reading the + * data file before attempting to instantiate the plugin). This array + * must always exist; if a host has no features, it MUST pass a single + * element array containing NULL (to simplify plugins). + * + * Note that instance initialisation should generally occur in + * activate() rather than here. If a host calls instantiate, it MUST + * call cleanup() at some point in the future. */ +LV2_Handle instantiate(const struct _LV2_Descriptor *descriptor, + double sample_rate, + const char *bundle_path, + const LV2_Feature *const *features) +{ + DGLV2 *dglv2 = new DGLV2; + + dglv2->in = new InputLV2(); + dglv2->out = new OutputLV2(); + + dglv2->buffer = NULL; + dglv2->buffer_size = 0; + + dglv2->dg = new DrumGizmo(dglv2->out, dglv2->in); + dglv2->dg->loadkit("/home/deva/docs/c/drumgizmo/kits/test/test.xml"); + dglv2->dg->init(true); + + return (LV2_Handle)dglv2; +} + +/** Function pointer that connects a port on a plugin instance to a memory + * location where the block of data for the port will be read/written. + * + * The data location is expected to be of the type defined in the + * plugin's data file (e.g. an array of float for an lv2:AudioPort). + * Memory issues are managed by the host. The plugin must read/write + * the data at these locations every time run() is called, data + * present at the time of this connection call MUST NOT be + * considered meaningful. + * + * The host MUST NOT try to connect a data buffer to a port index + * that is not defined in the RDF data for the plugin. If it does, + * the plugin's behaviour is undefined. + * + * connect_port() may be called more than once for a plugin instance + * to allow the host to change the buffers that the plugin is reading + * or writing. These calls may be made before or after activate() + * or deactivate() calls. Note that there may be realtime constraints + * on connect_port (see lv2:hardRTCapable in lv2.ttl). + * + * connect_port() MUST be called at least once for each port before + * run() is called. The plugin must pay careful attention to the block + * size passed to the run function as the block allocated may only just + * be large enough to contain the block of data (typically samples), and + * is not guaranteed to be constant. + * + * Plugin writers should be aware that the host may elect to use the + * same buffer for more than one port and even use the same buffer for + * both input and output (see lv2:inPlaceBroken in lv2.ttl). + * However, overlapped buffers or use of a single buffer for both + * audio and control data may result in unexpected behaviour. + * + * If the plugin has the feature lv2:hardRTCapable then there are + * various things that the plugin MUST NOT do within the connect_port() + * function (see lv2.ttl). */ +void connect_port(LV2_Handle instance, + uint32_t port, + void *data_location) +{ + DGLV2 *dglv2 = (DGLV2 *)instance; + + if(port == 0) {// MIDI in + dglv2->in->eventPort = (LV2_Event_Buffer*)data_location; + } else {// Audio Port + if(port - 1 < NUM_OUTPUTS) + dglv2->out->outputPort[port - 1] = (sample_t*)data_location; + } +} + +/** Function pointer that initialises a plugin instance and activates + * it for use. + * + * This is separated from instantiate() to aid real-time support and so + * that hosts can reinitialise a plugin instance by calling deactivate() + * and then activate(). In this case the plugin instance must reset all + * state information dependent on the history of the plugin instance + * except for any data locations provided by connect_port(). If there + * is nothing for activate() to do then the plugin writer may provide + * a NULL rather than an empty function. + * + * When present, hosts MUST call this function once before run() + * is called for the first time. This call SHOULD be made as close + * to the run() call as possible and indicates to real-time plugins + * that they are now live, however plugins MUST NOT rely on a prompt + * call to run() after activate(). activate() may not be called again + * unless deactivate() is called first (after which activate() may be + * called again, followed by deactivate, etc. etc.). If a host calls + * activate, it MUST call deactivate at some point in the future. + * + * Note that connect_port() may be called before or after a call to + * activate(). */ +void activate(LV2_Handle instance) +{ + DGLV2 *dglv2 = (DGLV2 *)instance; + //dglv2->dg->run(); + (void)dglv2; +} + +/** Function pointer that runs a plugin instance for a block. + * + * Two parameters are required: the first is a handle to the particular + * instance to be run and the second indicates the block size (in + * samples) for which the plugin instance may run. + * + * Note that if an activate() function exists then it must be called + * before run(). If deactivate() is called for a plugin instance then + * the plugin instance may not be reused until activate() has been + * called again. + * + * If the plugin has the feature lv2:hardRTCapable then there are + * various things that the plugin MUST NOT do within the run() + * function (see lv2.ttl). */ +void run(LV2_Handle instance, + uint32_t sample_count) +{ + static size_t pos = 0; + DGLV2 *dglv2 = (DGLV2 *)instance; + + if(dglv2->buffer_size != sample_count) { + if(dglv2->buffer) free(dglv2->buffer); + dglv2->buffer_size = sample_count; + dglv2->buffer = (sample_t*)malloc(sizeof(sample_t) * dglv2->buffer_size); + } + + dglv2->dg->run(pos, dglv2->buffer, dglv2->buffer_size); + + pos += sample_count; +} + +/** This is the counterpart to activate() (see above). If there is + * nothing for deactivate() to do then the plugin writer may provide + * a NULL rather than an empty function. + * + * Hosts must deactivate all activated units after they have been run() + * for the last time. This call SHOULD be made as close to the last + * run() call as possible and indicates to real-time plugins that + * they are no longer live, however plugins MUST NOT rely on prompt + * deactivation. Note that connect_port() may be called before or + * after a call to deactivate(). + * + * Note that deactivation is not similar to pausing as the plugin + * instance will be reinitialised when activate() is called to reuse it. + * Hosts MUST NOT call deactivate() unless activate() was previously + * called. */ +void deactivate(LV2_Handle instance) +{ + DGLV2 *dglv2 = (DGLV2 *)instance; + dglv2->dg->stop(); +} + +/** This is the counterpart to instantiate() (see above). Once an instance + * of a plugin has been finished with it can be deleted using this + * function. The instance handle passed ceases to be valid after + * this call. + * + * If activate() was called for a plugin instance then a corresponding + * call to deactivate() MUST be made before cleanup() is called. + * Hosts MUST NOT call cleanup() unless instantiate() was previously + * called. */ +void cleanup(LV2_Handle instance) +{ + DGLV2 *dglv2 = (DGLV2 *)instance; + delete dglv2->dg; + delete dglv2->in; + delete dglv2->out; +} + +/** Function pointer that can be used to return additional instance data for + * a plugin defined by some extenion (e.g. a struct containing additional + * function pointers). + * + * The actual type and meaning of the returned object MUST be specified + * precisely by the extension if it defines any extra data. If a particular + * extension does not define extra instance data, this function MUST return + * NULL for that extension's URI. If a plugin does not support any + * extensions that define extra instance data, this function pointer may be + * set to NULL rather than providing an empty function. + * + * The only parameter is the URI of the extension. The plugin MUST return + * NULL if it does not support the extension, but hosts SHOULD NOT use this + * as a discovery method (e.g. hosts should only call this function for + * extensions known to be supported by the plugin from the data file). + * + * The host is never responsible for freeing the returned value. + * + * NOTE: This function should return a struct (likely containing function + * pointers) and NOT a direct function pointer. Standard C and C++ do not + * allow type casts from void* to a function pointer type. To provide + * additional functions a struct should be returned containing the extra + * function pointers (which is valid standard code, and a much better idea + * for extensibility anyway). */ +const void* extension_data(const char *uri) +{ + return NULL; +} + +#ifdef __cplusplus +extern "C" { +#endif + +static const LV2_Descriptor descriptor = { + DRUMGIZMO_URI, + instantiate, + connect_port, + activate, + run, + deactivate, + cleanup, + extension_data +}; + +LV2_SYMBOL_EXPORT +const LV2_Descriptor* lv2_descriptor(uint32_t index) +{ + switch (index) { + case 0: + return &descriptor; + default: + return NULL; + } +} + +#ifdef __cplusplus +} +#endif |