source/includes/lv2/lv2_programs.h

   1 /*
   2   LV2 Programs Extension
   3   Copyright 2012 Filipe Coelho <falktx@falktx.com>
   4
   5   Permission to use, copy, modify, and/or distribute this software for any
   6   purpose with or without fee is hereby granted, provided that the above
   7   copyright notice and this permission notice appear in all copies.
   8
   9   THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10   WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11   MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12   ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16 */
  17
  18 /**
  19    @file lv2_programs.h
  20    C header for the LV2 programs extension <http://kxstudio.sf.net/ns/lv2ext/programs>.
  21 */
  22
  23 #ifndef LV2_PROGRAMS_H
  24 #define LV2_PROGRAMS_H
  25
  26 #include "lv2.h"
  27 #include "ui.h"
  28
  29 #define LV2_PROGRAMS_URI    "http://kxstudio.sf.net/ns/lv2ext/programs"
  30 #define LV2_PROGRAMS_PREFIX LV2_PROGRAMS_URI "#"
  31
  32 #define LV2_PROGRAMS__Host        LV2_PROGRAMS_PREFIX "Host"
  33 #define LV2_PROGRAMS__Interface   LV2_PROGRAMS_PREFIX "Interface"
  34 #define LV2_PROGRAMS__UIInterface LV2_PROGRAMS_PREFIX "UIInterface"
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 typedef void* LV2_Programs_Handle;
  41
  42 typedef struct _LV2_Program_Descriptor {
  43
  44     /** Bank number for this program. Note that this extension does not
  45         support MIDI-style separation of bank LSB and MSB values. There is
  46         no restriction on the set of available banks: the numbers do not
  47         need to be contiguous, there does not need to be a bank 0, etc. */
  48     uint32_t bank;
  49
  50     /** Program number (unique within its bank) for this program. There is
  51         no restriction on the set of available programs: the numbers do not
  52         need to be contiguous, there does not need to be a program 0, etc. */
  53     uint32_t program;
  54
  55     /** Name of the program. */
  56     const char * name;
  57
  58 } LV2_Program_Descriptor;
  59
  60 /**
  61    Programs extension, plugin data.
  62
  63    When the plugin's extension_data is called with argument LV2_PROGRAMS__Interface,
  64    the plugin MUST return an LV2_Programs_Instance structure, which remains valid
  65    for the lifetime of the plugin.
  66 */
  67 typedef struct _LV2_Programs_Interface {
  68     /**
  69      * get_program()
  70      *
  71      * This member is a function pointer that provides a description
  72      * of a program (named preset sound) available on this plugin.
  73      *
  74      * The index argument is an index into the plugin's list of
  75      * programs, not a program number as represented by the Program
  76      * field of the LV2_Program_Descriptor. (This distinction is
  77      * needed to support plugins that use non-contiguous program or
  78      * bank numbers.)
  79      *
  80      * This function returns a LV2_Program_Descriptor pointer that is
  81      * guaranteed to be valid only until the next call to get_program
  82      * or deactivate, on the same plugin instance. This function must
  83      * return NULL if passed an index argument out of range, so that
  84      * the host can use it to query the number of programs as well as
  85      * their properties.
  86      */
  87     const LV2_Program_Descriptor *(*get_program)(LV2_Handle handle,
  88                                                  uint32_t index);
  89
  90     /**
  91      * select_program()
  92      *
  93      * This member is a function pointer that selects a new program
  94      * for this plugin. The program change should take effect
  95      * immediately at the start of the next run() call. (This
  96      * means that a host providing the capability of changing programs
  97      * between any two notes on a track must vary the block size so as
  98      * to place the program change at the right place. A host that
  99      * wanted to avoid this would probably just instantiate a plugin
 100      * for each program.)
 101      *
 102      * Plugins should ignore a select_program() call with an invalid
 103      * bank or program.
 104      *
 105      * A plugin is not required to select any particular default
 106      * program on activate(): it's the host's duty to set a program
 107      * explicitly.
 108      *
 109      * A plugin is permitted to re-write the values of its input
 110      * control ports when select_program is called. The host should
 111      * re-read the input control port values and update its own
 112      * records appropriately. (This is the only circumstance in which
 113      * a LV2 plugin is allowed to modify its own control-input ports.)
 114      */
 115     void (*select_program)(LV2_Handle handle,
 116                            uint32_t bank,
 117                            uint32_t program);
 118
 119 } LV2_Programs_Interface;
 120
 121 /**
 122    Programs extension, UI data.
 123
 124    When the UI's extension_data is called with argument LV2_PROGRAMS__UIInterface,
 125    the UI MUST return an LV2_Programs_UI_Interface structure, which remains valid
 126    for the lifetime of the UI.
 127 */
 128 typedef struct _LV2_Programs_UI_Interface {
 129     /**
 130      * select_program()
 131      *
 132      * This is exactly the same as select_program in LV2_Programs_Instance,
 133      * but this struct relates to the UI instead of the plugin.
 134      *
 135      * When called, UIs should update their state to match the selected program.
 136      */
 137     void (*select_program)(LV2UI_Handle handle,
 138                            uint32_t bank,
 139                            uint32_t program);
 140
 141 } LV2_Programs_UI_Interface;
 142
 143 /**
 144     Feature data for LV2_PROGRAMS__Host.
 145 */
 146 typedef struct _LV2_Programs_Host {
 147     /**
 148      *  Opaque host data.
 149      */
 150     LV2_Programs_Handle handle;
 151
 152     /**
 153      * program_changed()
 154      *
 155      * Tell the host to reload a plugin's program.
 156      * Parameter handle MUST be the 'handle' member of this struct.
 157      * Parameter index is program index to change.
 158      * When index is -1, host should reload all the programs.
 159      *
 160      * The plugin MUST NEVER call this function on a RT context or during run().
 161      *
 162      * NOTE: This call is to inform the host about a program's bank, program or name change.
 163      *       It DOES NOT change the current selected program.
 164      */
 165     void (*program_changed)(LV2_Programs_Handle handle,
 166                             int32_t index);
 167
 168 } LV2_Programs_Host;
 169
 170 #ifdef __cplusplus
 171 } /* extern "C" */
 172 #endif
 173
 174 #endif /* LV2_PROGRAMS_H */