Update LV2 UI header.

git-svn-id: svn://localhost/ardour2/branches/3.0@11887 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 339 insertions, 198 deletions

diff --git a/gtk2_ardour/lv2_ui.h b/gtk2_ardour/lv2_ui.h
index fa0a711cf4..7526a5a287 100644
--- a/gtk2_ardour/lv2_ui.h
+++ b/gtk2_ardour/lv2_ui.h
@@ -1,241 +1,382 @@
-/* LV2 UI Extension
- * Copyright (C) 2006-2008 Lars Luthman <lars.luthman@gmail.com>
- * Copyright (C) 2009-2010 David Robillard <d@drobilla.net>
- *
- * Based on lv2.h, which was
- * Copyright (C) 2000-2002 Richard W.E. Furse, Paul Barton-Davis,
- *                         Stefan Westerfeld
- * Copyright (C) 2006 Steve Harris, David Robillard.
- *
- * This header is free software; you can redistribute it and/or modify it
- * under the terms of the GNU Lesser General Public License as published
- * by the Free Software Foundation; either version 2.1 of the License,
- * or (at your option) any later version.
- *
- * This header 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
- * USA.
- *
- */
-
-/** @file
- * C header for the LV2 UI extension <http://lv2plug.in/ns/extensions/ui>.
- */
+/*
+  LV2 UI Extension
+  Copyright 2009-2012 David Robillard <d@drobilla.net>
+  Copyright 2006-2011 Lars Luthman <lars.luthman@gmail.com>
+
+  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.
+*/
+
+/**
+   @file ui.h
+   C header for the LV2 UI extension <http://lv2plug.in/ns/extensions/ui>.
+*/
 
 #ifndef LV2_UI_H
 #define LV2_UI_H
 
-#include "lv2.h"
-
-#define LV2_UI_URI "http://lv2plug.in/ns/extensions/ui"
-
+#include <stdint.h>
+
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+
+#define LV2_UI_URI    "http://lv2plug.in/ns/extensions/ui"
+#define LV2_UI_PREFIX LV2_UI_URI "#"
+
+#define LV2_UI__GtkUI            LV2_UI_PREFIX "GtkUI"
+#define LV2_UI__PortNotification LV2_UI_PREFIX "PortNotification"
+#define LV2_UI__Qt4UI            LV2_UI_PREFIX "Qt4UI"
+#define LV2_UI__UI               LV2_UI_PREFIX "UI"
+#define LV2_UI__X11UI            LV2_UI_PREFIX "X11UI"
+#define LV2_UI__fixedSize        LV2_UI_PREFIX "fixedSize"
+#define LV2_UI__noUserResize     LV2_UI_PREFIX "noUserResize"
+#define LV2_UI__notifyType       LV2_UI_PREFIX "notifyType"
+#define LV2_UI__parent           LV2_UI_PREFIX "parent"
+#define LV2_UI__plugin           LV2_UI_PREFIX "plugin"
+#define LV2_UI__portIndex        LV2_UI_PREFIX "portIndex"
+#define LV2_UI__portMap          LV2_UI_PREFIX "portMap"
+#define LV2_UI__portNotification LV2_UI_PREFIX "portNotification"
+#define LV2_UI__portSubscribe    LV2_UI_PREFIX "portSubscribe"
+#define LV2_UI__resize           LV2_UI_PREFIX "resize"
+#define LV2_UI__touch            LV2_UI_PREFIX "touch"
+
+/**
+   The index returned by LV2_UI_Port_Port::port_index() for unknown ports.
+*/
+#define LV2UI_INVALID_PORT_INDEX ((uint32_t)-1)
 
 #ifdef __cplusplus
 extern "C" {
+#else
+#    include <stdbool.h>
 #endif
 
+/**
+   A pointer to some widget or other type of UI handle.
 
-/** A pointer to some widget or other type of UI handle.
-    The actual type is defined by the type URI of the UI.
-    All the functionality provided by this extension is toolkit
-    independent, the host only needs to pass the necessary callbacks and
-    display the widget, if possible. Plugins may have several UIs, in various
-    toolkits. */
+   The actual type is defined by the type of the UI.
+*/
 typedef void* LV2UI_Widget;
 
+/**
+   A pointer to an instance of a UI.
 
-/** A pointer to a particular instance of a UI.
-    It is valid to compare this to NULL (0 for C++) but otherwise the
-    host MUST not attempt to interpret it. The UI plugin may use it to
-    reference internal instance data. */
+   It is valid to compare this to NULL (0 for C++) but otherwise the host MUST
+   not attempt to interpret it.  The UI plugin may use it to reference internal
+   instance data.
+*/
 typedef void* LV2UI_Handle;
 
+/**
+   A pointer to a controller provided by the host.
 
-/** A pointer to a particular plugin controller, provided by the host.
-    It is valid to compare this to NULL (0 for C++) but otherwise the
-    UI plugin MUST not attempt to interpret it. The host may use it to
-    reference internal instance data. */
+   It is valid to compare this to NULL (0 for C++) but otherwise the UI plugin
+   MUST NOT attempt to interpret it.  The host may use it to reference internal
+   instance data.
+*/
 typedef void* LV2UI_Controller;
 
+/**
+   A pointer to opaque data for a feature.
+*/
+typedef void* LV2UI_Feature_Handle;
+
+/**
+   The type of the host-provided function that the UI can use to
+   send data to a plugin's input ports.
 
-/** The type of the host-provided function that the UI can use to
-    send data to a plugin's input ports. The @c buffer parameter must point
-    to a block of data, @c buffer_size bytes large. The contents of this buffer
-    and what the host should do with it depends on the value of the @c format
-    parameter.
-
-    The @c format parameter should either be 0 or a numeric ID for a "Transfer
-    mechanism". Transfer mechanisms are Features and may be defined in
-    meta-extensions. They specify how to translate the data buffers passed
-    to this function to input data for the plugin ports. If a UI wishes to
-    write data to an input port, it must list a transfer mechanism Feature
-    for that port's class as an optional or required feature (depending on
-    whether the UI will work without being able to write to that port or not).
-    The only exception is when the UI wants to write single float values to
-    input ports of the class lv2:ControlPort, in which case @c buffer_size
-    should always be 4, the buffer should always contain a single IEEE-754
-    float, and @c format should be 0.
-
-    The numeric IDs for the transfer mechanisms are provided by a
-    URI-to-integer mapping function provided by the host, using the URI Map
-    feature <http://lv2plug.in/ns/ext/uri-map> with the map URI
-    "http://lv2plug.in/ns/extensions/ui". Thus a UI that requires transfer
-    mechanism features also requires the URI Map feature, but this is
-    implicit - the UI does not have to list the URI map feature as a required
-    or optional feature in it's RDF data.
-
-    An UI MUST NOT pass a @c format parameter value (except 0) that has not
-    been returned by the host-provided URI mapping function for a
-    host-supported transfer mechanism feature URI.
-
-    The UI MUST NOT try to write to a port for which there is no specified
-    transfer mechanism, or to an output port. The UI is responsible for
-    allocating the buffer and deallocating it after the call.
+   The @c buffer parameter must point to a block of data, @c buffer_size bytes
+   large.  The format of this data and how the host should use it is defined by
+   the @c port_protocol.  This buffer is owned by the UI and is only valid for
+   the duration of this call.
+
+   The @c port_protocol parameter should either be 0 or the URID for a
+   ui:PortProtocol.  If it is 0, the protocol is implicitly ui:floatProtocol,
+   the port must be an lv2:ControlPort input, @c buffer must point to a single
+   float value, and @c buffer_size must be sizeof(float).
+
+   The UI SHOULD NOT use a PortProtocol not supported by the host (i.e. one not
+   passed by the host as a feature), but the host MUST gracefully ignore any
+   port_protocol it does not understand.
 */
 typedef void (*LV2UI_Write_Function)(LV2UI_Controller controller,
                                      uint32_t         port_index,
                                      uint32_t         buffer_size,
-                                     uint32_t         format,
+                                     uint32_t         port_protocol,
                                      const void*      buffer);
 
+/**
+   The implementation of a UI.
 
-/** This struct contains the implementation of a UI. A pointer to an
-    object of this type is returned by the lv2ui_descriptor() function.
+   A pointer to an object of this type is returned by the lv2ui_descriptor()
+   function.
 */
 typedef struct _LV2UI_Descriptor {
+	/**
+	   The URI for this UI (not for the plugin it controls).
+	*/
+	const char* URI;
+
+	/**
+	   Create a new UI object and return a handle to it.  This function works
+	   similarly to the instantiate() member in LV2_Descriptor.
+
+	   @param descriptor The descriptor for the UI that you want to instantiate.
+
+	   @param plugin_uri The URI of the plugin that this UI will control.
+
+	   @param bundle_path The path to the bundle containing the RDF data file
+	   that references this shared object file, including the trailing '/'.
+
+	   @param write_function A function provided by the host that the UI can use
+	   to send data to the plugin's input ports.
+
+	   @param controller A handle for the plugin instance that should be passed
+	   as the first parameter of @c write_function.
+
+	   @param widget A pointer to an LV2UI_Widget.  The UI will write a widget
+	   pointer to this location (what type of widget depends on the RDF class of
+	   the UI) that will be the main UI widget.
+
+	   @param features An array of LV2_Feature pointers.  The host must pass all
+	   feature URIs that it and the UI supports and any additional data, just
+	   like in the LV2 plugin instantiate() function.  Note that UI features and
+	   plugin features are NOT necessarily the same, they just share the same
+	   data structure - this will probably not be the same array as the one the
+	   plugin host passes to a plugin.
+
+	*/
+	LV2UI_Handle (*instantiate)(const struct _LV2UI_Descriptor* descriptor,
+	                            const char*                     plugin_uri,
+	                            const char*                     bundle_path,
+	                            LV2UI_Write_Function            write_function,
+	                            LV2UI_Controller                controller,
+	                            LV2UI_Widget*                   widget,
+	                            const LV2_Feature* const*       features);
+
+
+	/**
+	   Destroy the UI object and the associated widget. The host must not try
+	   to access the widget after calling this function.
+	*/
+	void (*cleanup)(LV2UI_Handle ui);
+
+	/**
+	   Tell the UI that something interesting has happened at a plugin port.
+
+	   What is interesting and how it is written to the buffer passed to this
+	   function is defined by the @c format parameter, which has the same
+	   meaning as in LV2UI_Write_Function.  The only exception is ports of the
+	   class lv2:ControlPort, for which this function should be called when the
+	   port value changes (it does not have to be called for every single change
+	   if the host's UI thread has problems keeping up with the thread the
+	   plugin is running in), @c buffer_size should be 4, the buffer should
+	   contain a single IEEE-754 float, and @c format should be 0.
+
+	   By default, the host should only call this function for input ports of
+	   the lv2:ControlPort class.  However, this can be modified by using
+	   ui:portNotification in the UI data, or the ui:portSubscribe feature.
+
+	   The @c buffer is only valid during the time of this function call, so if
+	   the UI wants to keep it for later use it has to copy the contents to an
+	   internal buffer.
+
+	   This member may be set to NULL if the UI is not interested in any
+	   port events.
+	*/
+	void (*port_event)(LV2UI_Handle ui,
+	                   uint32_t     port_index,
+	                   uint32_t     buffer_size,
+	                   uint32_t     format,
+	                   const void*  buffer);
+
+	/**
+	   Return a data structure associated with an extension URI, for example
+	   a struct containing additional function pointers.
+
+	   Avoid returning function pointers directly since standard C/C++ has no
+	   valid way of casting a void* to a function pointer. This member may be set
+	   to NULL if the UI is not interested in supporting any extensions. This is
+	   similar to the extension_data() member in LV2_Descriptor.
+	*/
+	const void* (*extension_data)(const char* uri);
+} LV2UI_Descriptor;
 
-  /** The URI for this UI (not for the plugin it controls). */
-  const char* URI;
-
-  /** Create a new UI object and return a handle to it. This function works
-      similarly to the instantiate() member in LV2_Descriptor.
-
-      @param descriptor The descriptor for the UI that you want to instantiate.
-      @param plugin_uri The URI of the plugin that this UI will control.
-      @param bundle_path The path to the bundle containing the RDF data file
-                         that references this shared object file, including the
-                         trailing '/'.
-      @param write_function A function provided by the host that the UI can
-                            use to send data to the plugin's input ports.
-      @param controller A handle for the plugin instance that should be passed
-                        as the first parameter of @c write_function.
-      @param widget A pointer to an LV2UI_Widget. The UI will write a
-                    widget pointer to this location (what type of widget
-                    depends on the RDF class of the UI) that will be the
-                    main UI widget.
-      @param features An array of LV2_Feature pointers. The host must pass
-                      all feature URIs that it and the UI supports and any
-                      additional data, just like in the LV2 plugin
-                      instantiate() function. Note that UI features and plugin
-                      features are NOT necessarily the same, they just share
-                      the same data structure - this will probably not be the
-                      same array as the one the plugin host passes to a
-                      plugin.
-  */
-  LV2UI_Handle (*instantiate)(const struct _LV2UI_Descriptor* descriptor,
-                              const char*                     plugin_uri,
-                              const char*                     bundle_path,
-                              LV2UI_Write_Function            write_function,
-                              LV2UI_Controller                controller,
-                              LV2UI_Widget*                   widget,
-                              const LV2_Feature* const*       features);
-
-
-  /** Destroy the UI object and the associated widget. The host must not try
-      to access the widget after calling this function.
-   */
-  void (*cleanup)(LV2UI_Handle ui);
-
-  /** Tell the UI that something interesting has happened at a plugin port.
-      What is interesting and how it is written to the buffer passed to this
-      function is defined by the @c format parameter, which has the same
-      meaning as in LV2UI_Write_Function. The only exception is ports of the
-      class lv2:ControlPort, for which this function should be called
-      when the port value changes (it does not have to be called for every
-      single change if the host's UI thread has problems keeping up with the
-      thread the plugin is running in), @c buffer_size should be 4, the buffer
-      should contain a single IEEE-754 float, and @c format should be 0.
-
-      By default, the host should only call this function for input ports of
-      the lv2:ControlPort class. However, the default setting can be modified
-      by using the following URIs in the UI's RDF data:
-      <pre>
-      uiext:portNotification
-      uiext:noPortNotification
-      uiext:plugin
-      uiext:portIndex
-      </pre>
-      For example, if you want the UI with uri
-      <code><http://my.pluginui></code> for the plugin with URI
-      <code><http://my.plugin></code> to get notified when the value of the
-      output control port with index 4 changes, you would use the following
-      in the RDF for your UI:
-      <pre>
-      <http://my.pluginui> uiext:portNotification [ uiext:plugin <http://my.plugin> ;
-                                                    uiext:portIndex 4 ] .
-      </pre>
-      and similarly with <code>uiext:noPortNotification</code> if you wanted
-      to prevent notifications for a port for which it would be on by default
-      otherwise. The UI is not allowed to request notifications for ports of
-      types for which no transfer mechanism is specified, if it does it should
-      be considered broken and the host should not load it.
-
-      The @c buffer is only valid during the time of this function call, so if
-      the UI wants to keep it for later use it has to copy the contents to an
-      internal buffer.
-
-      This member may be set to NULL if the UI is not interested in any
-      port events.
-  */
-  void (*port_event)(LV2UI_Handle ui,
-                     uint32_t     port_index,
-                     uint32_t     buffer_size,
-                     uint32_t     format,
-                     const void*  buffer);
-
-  /** Returns a data structure associated with an extension URI, for example
-      a struct containing additional function pointers. Avoid returning
-      function pointers directly since standard C/C++ has no valid way of
-      casting a void* to a function pointer. This member may be set to NULL
-      if the UI is not interested in supporting any extensions. This is similar
-      to the extension_data() member in LV2_Descriptor.
-  */
-  const void* (*extension_data)(const char* uri);
+/**
+   UI Resize Feature (LV2_UI__resize)
 
-} LV2UI_Descriptor;
+   This structure may be used in two ways: as a feature passed by the host via
+   LV2UI_Descriptor::instantiate(), or as extension data provided by a UI via
+   LV2UI_Descriptor::extension_data()).
+*/
+typedef struct _LV2UI_Resize {
+	/**
+	   Pointer to opaque data which must be passed to ui_resize().
+	*/
+	LV2UI_Feature_Handle handle;
+
+	/**
+	   Request or advertise a size change.
+
+	   When this struct is provided by the host, the UI may call this
+	   function to inform the host about the size of the UI.
 
+	   When this struct is provided by the UI, the host may call this
+	   function to notify the UI that it should change its size accordingly.
 
+	   @return 0 on success.
+	*/
+	int (*ui_resize)(LV2UI_Feature_Handle handle, int width, int height);
+} LV2UI_Resize;
 
-/** A plugin UI programmer must include a function called "lv2ui_descriptor"
-    with the following function prototype within the shared object
-    file. This function will have C-style linkage (if you are using
-    C++ this is taken care of by the 'extern "C"' clause at the top of
-    the file). This function will be accessed by the UI host using the
-    @c dlsym() function and called to get a LV2UI_UIDescriptor for the
-    wanted plugin.
+/**
+   Port Map Feature (LV2_UI__portMap).
 
-    Just like lv2_descriptor(), this function takes an index parameter. The
-    index should only be used for enumeration and not as any sort of ID number -
-    the host should just iterate from 0 and upwards until the function returns
-    NULL or a descriptor with an URI matching the one the host is looking for.
+   This feature can be used by the UI to get the index for a port with the
+   given symbol.  This makes it possible to implement and distribute a UI
+   separately from the plugin (since symbol is a guaranteed stable port
+   identifier while index is not).
+*/
+typedef struct _LV2UI_Port_Map {
+	/**
+	   Pointer to opaque data which must be passed to ui_resize().
+	*/
+	LV2UI_Feature_Handle handle;
+
+	/**
+	   Get the index for the port with the given @p symbol.
+
+	   @return The index of the port, or LV2_UI_INVALID_PORT_INDEX if no such
+	   port is found.
+	*/
+	uint32_t (*port_index)(LV2UI_Feature_Handle handle, const char* symbol);
+} LV2UI_Port_Map;
+
+/**
+   Port subscription feature (LV2_UI__portSubscribe);
+*/
+typedef struct _LV2UI_Port_Subscribe {
+	/**
+	   Pointer to opaque data which must be passed to ui_resize().
+	*/
+	LV2UI_Feature_Handle handle;
+
+	/**
+	   Subscribe to updates for a port.
+
+	   This means that the host will call the UI's port_event() function when
+	   the port value changes (as defined by protocol).
+
+	   Calling this function with the same @c port_index and @c port_protocol
+	   as an already active subscription has no effect.
+
+	   @param handle The handle field of this struct.
+	   @param port_index The index of the port.
+	   @param port_protocol The URID of the ui:PortProtocol.
+	   @param features Features for this subscription.
+	   @return 0 on success.
+	*/
+	uint32_t (*subscribe)(LV2UI_Feature_Handle      handle,
+	                      uint32_t                  port_index,
+	                      uint32_t                  port_protocol,
+	                      const LV2_Feature* const* features);
+
+	/**
+	   Unsubscribe from updates for a port.
+
+	   This means that the host will cease calling calling port_event() when
+	   the port value changes.
+
+	   Calling this function with a @c port_index and @c port_protocol that
+	   does not refer to an active port subscription has no effect.
+
+	   @param handle The handle field of this struct.
+	   @param port_index The index of the port.
+	   @param port_protocol The URID of the ui:PortProtocol.
+	   @param features Features for this subscription.
+	   @return 0 on success.
+	*/
+	uint32_t (*unsubscribe)(LV2UI_Feature_Handle      handle,
+	                        uint32_t                  port_index,
+	                        uint32_t                  port_protocol,
+	                        const LV2_Feature* const* features);
+} LV2UI_Port_Subscribe;
+
+/**
+   A feature to notify the host the user has grabbed a UI control.
+*/
+typedef struct _LV2UI_Touch {
+	/**
+	   Pointer to opaque data which must be passed to ui_resize().
+	*/
+	LV2UI_Feature_Handle handle;
+
+	/**
+	   Notify the host that a control has been grabbed or released.
+
+	   @param handle The handle field of this struct.
+	   @param port_index The index of the port associated with the control.
+	   @param grabbed If true, the control has been grabbed, otherwise the
+	   control has been released.
+	*/
+	void (*touch)(LV2UI_Feature_Handle handle,
+	              uint32_t             port_index,
+	              bool                 grabbed);
+} LV2UI_Touch;
+
+/**
+   Peak data for a slice of time, the update format for ui:peakProtocol.
+*/
+typedef struct _LV2UI_Peak_Data {
+	/**
+	   The start of the measurement period.  This is just a running counter
+	   that is only meaningful in comparison to previous values and must not be
+	   interpreted as an absolute time.
+	*/
+	uint32_t period_start;
+
+	/**
+	   The size of the measurement period, in the same units as period_start.
+	*/
+	uint32_t period_size;
+
+	/**
+	   The peak value for the measurement period. This should be the maximal
+	   value for abs(sample) over all the samples in the period.
+	*/
+	float peak;
+} LV2UI_Peak_Data;
+
+/**
+   A plugin UI programmer must include a function called "lv2ui_descriptor"
+   with the following function prototype within the shared object file.  This
+   function will have C-style linkage (if you are using C++ this is taken care
+   of by the 'extern "C"' clause at the top of the file).  This function is
+   loaded from the library by the UI host and called to get a
+   LV2UI_Descriptor for the wanted plugin.
+
+   Just like lv2_descriptor(), this function takes an index parameter.  The
+   index should only be used for enumeration and not as any sort of ID number -
+   the host should just iterate from 0 and upwards until the function returns
+   NULL or a descriptor with an URI matching the one the host is looking for.
 */
 const LV2UI_Descriptor* lv2ui_descriptor(uint32_t index);
 
-
-/** This is the type of the lv2ui_descriptor() function. */
+/**
+   The type of the lv2ui_descriptor() function.
+*/
 typedef const LV2UI_Descriptor* (*LV2UI_DescriptorFunction)(uint32_t index);
 
-
-
 #ifdef __cplusplus
 }
 #endif
 
-
-#endif
+#endif /* LV2_UI_H */