/* GStreamer Navigation
* Copyright (C) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
* Copyright (C) 2007-2009 Jan Schmidt <thaytan@noraisin.net>
*
* navigation.c: navigation event virtual class function wrappers
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library 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.
*/
/**
* SECTION:gstnavigation
* @title: GstNavigation
* @short_description: Interface for creating, sending and parsing navigation
* events.
*
* The Navigation interface is used for creating and injecting navigation related
* events such as mouse button presses, cursor motion and key presses. The associated
* library also provides methods for parsing received events, and for sending and
* receiving navigation related bus events. One main usecase is DVD menu navigation.
*
* The main parts of the API are:
*
* * The GstNavigation interface, implemented by elements which provide an application
* with the ability to create and inject navigation events into the pipeline.
* * GstNavigation event handling API. GstNavigation events are created in response to
* calls on a GstNavigation interface implementation, and sent in the pipeline. Upstream
* elements can use the navigation event API functions to parse the contents of received
* messages.
*
* * GstNavigation message handling API. GstNavigation messages may be sent on the message
* bus to inform applications of navigation related changes in the pipeline, such as the
* mouse moving over a clickable region, or the set of available angles changing.
*
* The GstNavigation message functions provide functions for creating and parsing
* custom bus messages for signaling GstNavigation changes.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/video/navigation.h>
#include <gst/video/video-enumtypes.h>
static void gst_navigation_class_init (GstNavigationInterface * iface);
#define GST_NAVIGATION_MESSAGE_NAME "GstNavigationMessage"
#define GST_NAVIGATION_QUERY_NAME "GstNavigationQuery"
#define GST_NAVIGATION_EVENT_NAME "application/x-gst-navigation"
#define WARN_IF_FAIL(exp,msg) if(G_UNLIKELY(!(exp))){g_warning("%s",(msg));}
GType
gst_navigation_get_type (void)
{
static GType gst_navigation_type = 0;
if (!gst_navigation_type) {
static const GTypeInfo gst_navigation_info = {
sizeof (GstNavigationInterface),
(GBaseInitFunc) gst_navigation_class_init,
NULL,
NULL,
NULL,
NULL,
0,
0,
NULL,
};
gst_navigation_type = g_type_register_static (G_TYPE_INTERFACE,
"GstNavigation", &gst_navigation_info, 0);
}
return gst_navigation_type;
}
static void
gst_navigation_class_init (GstNavigationInterface * iface)
{
/* default virtual functions */
iface->send_event = NULL;
}
/* The interface implementer should make sure that the object can handle
* the event. */
void
gst_navigation_send_event (GstNavigation * navigation, GstStructure * structure)
{
GstNavigationInterface *iface = GST_NAVIGATION_GET_INTERFACE (navigation);
if (iface->send_event) {
iface->send_event (navigation, structure);
} else {
gst_structure_free (structure);
}
}
/**
* gst_navigation_send_key_event:
* @navigation: The navigation interface instance
* @event: The type of the key event. Recognised values are "key-press" and
* "key-release"
* @key: Character representation of the key. This is typically as produced
* by XKeysymToString.
*/
void
gst_navigation_send_key_event (GstNavigation * navigation, const char *event,
const char *key)
{
g_return_if_fail (g_strcmp0 (event, "key-press") == 0 ||
g_strcmp0 (event, "key-release") == 0);
gst_navigation_send_event (navigation,
gst_structure_new (GST_NAVIGATION_EVENT_NAME, "event", G_TYPE_STRING,
event, "key", G_TYPE_STRING, key, NULL));
}
/**
* gst_navigation_send_mouse_event:
* @navigation: The navigation interface instance
* @event: The type of mouse event, as a text string. Recognised values are
* "mouse-button-press", "mouse-button-release" and "mouse-move".
* @button: The button number of the button being pressed or released. Pass 0
* for mouse-move events.
* @x: The x coordinate of the mouse event.
* @y: The y coordinate of the mouse event.
*
* Sends a mouse event to the navigation interface. Mouse event coordinates
* are sent relative to the display space of the related output area. This is
* usually the size in pixels of the window associated with the element
* implementing the #GstNavigation interface.
*
*/
void
gst_navigation_send_mouse_event (GstNavigation * navigation, const char *event,
int button, double x, double y)
{
g_return_if_fail (g_strcmp0 (event, "mouse-button-press") == 0 ||
g_strcmp0 (event, "mouse-button-release") == 0 ||
g_strcmp0 (event, "mouse-move") == 0);
gst_navigation_send_event (navigation,
gst_structure_new (GST_NAVIGATION_EVENT_NAME, "event", G_TYPE_STRING,
event, "button", G_TYPE_INT, button, "pointer_x", G_TYPE_DOUBLE, x,
"pointer_y", G_TYPE_DOUBLE, y, NULL));
}
/**
* gst_navigation_send_command:
* @navigation: The navigation interface instance
* @command: The command to issue
*
* Sends the indicated command to the navigation interface.
*/
void
gst_navigation_send_command (GstNavigation * navigation,
GstNavigationCommand command)
{
gst_navigation_send_event (navigation,
gst_structure_new (GST_NAVIGATION_EVENT_NAME, "event", G_TYPE_STRING,
"command", "command-code", G_TYPE_UINT, (guint) command, NULL));
}
/* Navigation Queries */
#define GST_NAVIGATION_QUERY_HAS_TYPE(query,query_type) \
(gst_navigation_query_get_type (query) == GST_NAVIGATION_QUERY_ ## query_type)
/**
* gst_navigation_query_get_type:
* @query: The query to inspect
*
* Inspect a #GstQuery and return the #GstNavigationQueryType associated with
* it if it is a #GstNavigation query.
*
* Returns: The #GstNavigationQueryType of the query, or
* #GST_NAVIGATION_QUERY_INVALID
*/
GstNavigationQueryType
gst_navigation_query_get_type (GstQuery * query)
{
const GstStructure *s;
const gchar *q_type;
if (query == NULL || GST_QUERY_TYPE (query) != GST_QUERY_CUSTOM)
return GST_NAVIGATION_QUERY_INVALID;
s = gst_query_get_structure (query);
if (s == NULL || !gst_structure_has_name (s, GST_NAVIGATION_QUERY_NAME))
return GST_NAVIGATION_QUERY_INVALID;
q_type = gst_structure_get_string (s, "type");
if (q_type == NULL)
return GST_NAVIGATION_QUERY_INVALID;
if (g_str_equal (q_type, "commands"))
return GST_NAVIGATION_QUERY_COMMANDS;
else if (g_str_equal (q_type, "angles"))
return GST_NAVIGATION_QUERY_ANGLES;
return GST_NAVIGATION_QUERY_INVALID;
}
/**
* gst_navigation_query_new_commands:
*
* Create a new #GstNavigation commands query. When executed, it will
* query the pipeline for the set of currently available commands.
*
* Returns: The new query.
*/
GstQuery *
gst_navigation_query_new_commands (void)
{
GstQuery *query;
GstStructure *structure;
structure = gst_structure_new (GST_NAVIGATION_QUERY_NAME,
"type", G_TYPE_STRING, "commands", NULL);
query = gst_query_new_custom (GST_QUERY_CUSTOM, structure);
return query;
}
static void
gst_query_list_add_command (GValue * list, GstNavigationCommand val)
{
GValue item = { 0, };
g_value_init (&item, GST_TYPE_NAVIGATION_COMMAND);
g_value_set_enum (&item, val);
gst_value_list_append_value (list, &item);
g_value_unset (&item);
}
/**
* gst_navigation_query_set_commands:
* @query: a #GstQuery
* @n_cmds: the number of commands to set.
* @...: A list of @GstNavigationCommand values, @n_cmds entries long.
*
* Set the #GstNavigation command query result fields in @query. The number
* of commands passed must be equal to @n_commands.
*/
void
gst_navigation_query_set_commands (GstQuery * query, gint n_cmds, ...)
{
va_list ap;
GValue list = { 0, };
GstStructure *structure;
gint i;
g_return_if_fail (GST_NAVIGATION_QUERY_HAS_TYPE (query, COMMANDS));
g_value_init (&list, GST_TYPE_LIST);
va_start (ap, n_cmds);
for (i = 0; i < n_cmds; i++) {
GstNavigationCommand val = va_arg (ap, GstNavigationCommand);
gst_query_list_add_command (&list, val);
}
va_end (ap);
structure = gst_query_writable_structure (query);
gst_structure_take_value (structure, "commands", &list);
}
/**
* gst_navigation_query_set_commandsv:
* @query: a #GstQuery
* @n_cmds: the number of commands to set.
* @cmds: (array length=n_cmds): An array containing @n_cmds
* @GstNavigationCommand values.
*
* Set the #GstNavigation command query result fields in @query. The number
* of commands passed must be equal to @n_commands.
*/
void
gst_navigation_query_set_commandsv (GstQuery * query, gint n_cmds,
GstNavigationCommand * cmds)
{
GValue list = { 0, };
GstStructure *structure;
gint i;
g_return_if_fail (GST_NAVIGATION_QUERY_HAS_TYPE (query, COMMANDS));
g_value_init (&list, GST_TYPE_LIST);
for (i = 0; i < n_cmds; i++) {
gst_query_list_add_command (&list, cmds[i]);
}
structure = gst_query_writable_structure (query);
gst_structure_take_value (structure, "commands", &list);
}
/**
* gst_navigation_query_parse_commands_length:
* @query: a #GstQuery
* @n_cmds: (out) (optional): the number of commands in this query.
*
* Parse the number of commands in the #GstNavigation commands @query.
*
* Returns: %TRUE if the query could be successfully parsed. %FALSE if not.
*/
gboolean
gst_navigation_query_parse_commands_length (GstQuery * query, guint * n_cmds)
{
const GstStructure *structure;
const GValue *list;
g_return_val_if_fail (GST_NAVIGATION_QUERY_HAS_TYPE (query, COMMANDS), FALSE);
if (n_cmds == NULL)
return TRUE;
structure = gst_query_get_structure (query);
list = gst_structure_get_value (structure, "commands");
if (list == NULL)
*n_cmds = 0;
else
*n_cmds = gst_value_list_get_size (list);
return TRUE;
}
/**
* gst_navigation_query_parse_commands_nth:
* @query: a #GstQuery
* @nth: the nth command to retrieve.
* @cmd: (out) (optional): a pointer to store the nth command into.
*
* Parse the #GstNavigation command query and retrieve the @nth command from
* it into @cmd. If the list contains less elements than @nth, @cmd will be
* set to #GST_NAVIGATION_COMMAND_INVALID.
*
* Returns: %TRUE if the query could be successfully parsed. %FALSE if not.
*/
gboolean
gst_navigation_query_parse_commands_nth (GstQuery * query, guint nth,
GstNavigationCommand * cmd)
{
const GstStructure *structure;
const GValue *list;
g_return_val_if_fail (GST_NAVIGATION_QUERY_HAS_TYPE (query, COMMANDS), FALSE);
if (cmd == NULL)
return TRUE;
structure = gst_query_get_structure (query);
list = gst_structure_get_value (structure, "commands");
if (list == NULL) {
*cmd = GST_NAVIGATION_COMMAND_INVALID;
} else {
if (nth < gst_value_list_get_size (list)) {
*cmd = (GstNavigationCommand)
g_value_get_enum (gst_value_list_get_value (list, nth));
} else
*cmd = GST_NAVIGATION_COMMAND_INVALID;
}
return TRUE;
}
/**
* gst_navigation_query_new_angles:
*
* Create a new #GstNavigation angles query. When executed, it will
* query the pipeline for the set of currently available angles, which may be
* greater than one in a multiangle video.
*
* Returns: The new query.
*/
GstQuery *
gst_navigation_query_new_angles (void)
{
GstQuery *query;
GstStructure *structure;
structure = gst_structure_new (GST_NAVIGATION_QUERY_NAME,
"type", G_TYPE_STRING, "angles", NULL);
query = gst_query_new_custom (GST_QUERY_CUSTOM, structure);
return query;
}
/**
* gst_navigation_query_set_angles:
* @query: a #GstQuery
* @cur_angle: the current viewing angle to set.
* @n_angles: the number of viewing angles to set.
*
* Set the #GstNavigation angles query result field in @query.
*/
void
gst_navigation_query_set_angles (GstQuery * query, guint cur_angle,
guint n_angles)
{
GstStructure *structure;
g_return_if_fail (GST_NAVIGATION_QUERY_HAS_TYPE (query, ANGLES));
structure = gst_query_writable_structure (query);
gst_structure_set (structure,
"angle", G_TYPE_UINT, cur_angle, "angles", G_TYPE_UINT, n_angles, NULL);
}
/**
* gst_navigation_query_parse_angles:
* @query: a #GstQuery
* @cur_angle: (out) (optional): Pointer to a #guint into which to store the
* currently selected angle value from the query, or NULL
* @n_angles: (out) (optional): Pointer to a #guint into which to store the
* number of angles value from the query, or NULL
*
* Parse the current angle number in the #GstNavigation angles @query into the
* #guint pointed to by the @cur_angle variable, and the number of available
* angles into the #guint pointed to by the @n_angles variable.
*
* Returns: %TRUE if the query could be successfully parsed. %FALSE if not.
*/
gboolean
gst_navigation_query_parse_angles (GstQuery * query, guint * cur_angle,
guint * n_angles)
{
const GstStructure *structure;
gboolean ret = TRUE;
g_return_val_if_fail (GST_NAVIGATION_QUERY_HAS_TYPE (query, ANGLES), FALSE);
structure = gst_query_get_structure (query);
if (cur_angle)
ret &= gst_structure_get_uint (structure, "angle", cur_angle);
if (n_angles)
ret &= gst_structure_get_uint (structure, "angles", n_angles);
WARN_IF_FAIL (ret, "Couldn't extract details from angles query");
return ret;
}
/* Navigation Messages */
#define GST_NAVIGATION_MESSAGE_HAS_TYPE(msg,msg_type) \
(gst_navigation_message_get_type (msg) == GST_NAVIGATION_MESSAGE_ ## msg_type)
/**
* gst_navigation_message_get_type:
* @message: A #GstMessage to inspect.
*
* Check a bus message to see if it is a #GstNavigation event, and return
* the #GstNavigationMessageType identifying the type of the message if so.
*
* Returns: The type of the #GstMessage, or
* #GST_NAVIGATION_MESSAGE_INVALID if the message is not a #GstNavigation
* notification.
*/
GstNavigationMessageType
gst_navigation_message_get_type (GstMessage * message)
{
const GstStructure *s;
const gchar *m_type;
if (message == NULL || GST_MESSAGE_TYPE (message) != GST_MESSAGE_ELEMENT)
return GST_NAVIGATION_MESSAGE_INVALID;
s = gst_message_get_structure (message);
if (s == NULL || !gst_structure_has_name (s, GST_NAVIGATION_MESSAGE_NAME))
return GST_NAVIGATION_MESSAGE_INVALID;
m_type = gst_structure_get_string (s, "type");
if (m_type == NULL)
return GST_NAVIGATION_MESSAGE_INVALID;
if (g_str_equal (m_type, "mouse-over"))
return GST_NAVIGATION_MESSAGE_MOUSE_OVER;
else if (g_str_equal (m_type, "commands-changed"))
return GST_NAVIGATION_MESSAGE_COMMANDS_CHANGED;
else if (g_str_equal (m_type, "angles-changed"))
return GST_NAVIGATION_MESSAGE_ANGLES_CHANGED;
else if (g_str_equal (m_type, "event"))
return GST_NAVIGATION_MESSAGE_EVENT;
return GST_NAVIGATION_MESSAGE_INVALID;
}
/**
* gst_navigation_message_new_mouse_over:
* @src: A #GstObject to set as source of the new message.
* @active: %TRUE if the mouse has entered a clickable area of the display.
* %FALSE if it over a non-clickable area.
*
* Creates a new #GstNavigation message with type
* #GST_NAVIGATION_MESSAGE_MOUSE_OVER.
*
* Returns: The new #GstMessage.
*/
GstMessage *
gst_navigation_message_new_mouse_over (GstObject * src, gboolean active)
{
GstStructure *s;
GstMessage *m;
s = gst_structure_new (GST_NAVIGATION_MESSAGE_NAME,
"type", G_TYPE_STRING, "mouse-over", "active", G_TYPE_BOOLEAN, active,
NULL);
m = gst_message_new_custom (GST_MESSAGE_ELEMENT, src, s);
return m;
}
/**
* gst_navigation_message_parse_mouse_over:
* @message: A #GstMessage to inspect.
* @active: (out) (optional): A pointer to a gboolean to receive the
* active/inactive state, or NULL.
*
* Parse a #GstNavigation message of type #GST_NAVIGATION_MESSAGE_MOUSE_OVER
* and extract the active/inactive flag. If the mouse over event is marked
* active, it indicates that the mouse is over a clickable area.
*
* Returns: %TRUE if the message could be successfully parsed. %FALSE if not.
*/
gboolean
gst_navigation_message_parse_mouse_over (GstMessage * message,
gboolean * active)
{
if (!GST_NAVIGATION_MESSAGE_HAS_TYPE (message, MOUSE_OVER))
return FALSE;
if (active) {
const GstStructure *s = gst_message_get_structure (message);
if (!gst_structure_get_boolean (s, "active", active))
return FALSE;
}
return TRUE;
}
/**
* gst_navigation_message_new_event:
* @src: A #GstObject to set as source of the new message.
* @event: (transfer none): A navigation #GstEvent
*
* Creates a new #GstNavigation message with type
* #GST_NAVIGATION_MESSAGE_EVENT.
*
* Returns: The new #GstMessage.
*
* Since: 1.6
*/
GstMessage *
gst_navigation_message_new_event (GstObject * src, GstEvent * event)
{
GstStructure *s;
GstMessage *m;
s = gst_structure_new (GST_NAVIGATION_MESSAGE_NAME,
"type", G_TYPE_STRING, "event", "event", GST_TYPE_EVENT, event, NULL);
m = gst_message_new_custom (GST_MESSAGE_ELEMENT, src, s);
return m;
}
/**
* gst_navigation_message_parse_event:
* @message: A #GstMessage to inspect.
* @event: (out) (optional) (transfer full): a pointer to a #GstEvent to receive
* the contained navigation event.
*
* Parse a #GstNavigation message of type #GST_NAVIGATION_MESSAGE_EVENT
* and extract contained #GstEvent. The caller must unref the @event when done
* with it.
*
* Returns: %TRUE if the message could be successfully parsed. %FALSE if not.
*
* Since: 1.6
*/
gboolean
gst_navigation_message_parse_event (GstMessage * message, GstEvent ** event)
{
if (!GST_NAVIGATION_MESSAGE_HAS_TYPE (message, EVENT))
return FALSE;
if (event) {
const GstStructure *s = gst_message_get_structure (message);
if (!gst_structure_get (s, "event", GST_TYPE_EVENT, event, NULL))
return FALSE;
}
return TRUE;
}
/**
* gst_navigation_message_new_commands_changed:
* @src: A #GstObject to set as source of the new message.
*
* Creates a new #GstNavigation message with type
* #GST_NAVIGATION_MESSAGE_COMMANDS_CHANGED
*
* Returns: The new #GstMessage.
*/
GstMessage *
gst_navigation_message_new_commands_changed (GstObject * src)
{
GstStructure *s;
GstMessage *m;
s = gst_structure_new (GST_NAVIGATION_MESSAGE_NAME,
"type", G_TYPE_STRING, "commands-changed", NULL);
m = gst_message_new_custom (GST_MESSAGE_ELEMENT, src, s);
return m;
}
/**
* gst_navigation_message_new_angles_changed:
* @src: A #GstObject to set as source of the new message.
* @cur_angle: The currently selected angle.
* @n_angles: The number of viewing angles now available.
*
* Creates a new #GstNavigation message with type
* #GST_NAVIGATION_MESSAGE_ANGLES_CHANGED for notifying an application
* that the current angle, or current number of angles available in a
* multiangle video has changed.
*
* Returns: The new #GstMessage.
*/
GstMessage *
gst_navigation_message_new_angles_changed (GstObject * src, guint cur_angle,
guint n_angles)
{
GstStructure *s;
GstMessage *m;
s = gst_structure_new (GST_NAVIGATION_MESSAGE_NAME,
"type", G_TYPE_STRING, "angles-changed",
"angle", G_TYPE_UINT, cur_angle, "angles", G_TYPE_UINT, n_angles, NULL);
m = gst_message_new_custom (GST_MESSAGE_ELEMENT, src, s);
return m;
}
/**
* gst_navigation_message_parse_angles_changed:
* @message: A #GstMessage to inspect.
* @cur_angle: (out) (optional): A pointer to a #guint to receive the new
* current angle number, or NULL
* @n_angles: (out) (optional): A pointer to a #guint to receive the new angle
* count, or NULL.
*
* Parse a #GstNavigation message of type GST_NAVIGATION_MESSAGE_ANGLES_CHANGED
* and extract the @cur_angle and @n_angles parameters.
*
* Returns: %TRUE if the message could be successfully parsed. %FALSE if not.
*/
gboolean
gst_navigation_message_parse_angles_changed (GstMessage * message,
guint * cur_angle, guint * n_angles)
{
const GstStructure *s;
gboolean ret = TRUE;
g_return_val_if_fail (GST_NAVIGATION_MESSAGE_HAS_TYPE (message,
ANGLES_CHANGED), FALSE);
s = gst_message_get_structure (message);
if (cur_angle)
ret &= gst_structure_get_uint (s, "angle", cur_angle);
if (n_angles)
ret &= gst_structure_get_uint (s, "angles", n_angles);
WARN_IF_FAIL (ret, "Couldn't extract details from angles-changed event");
return ret;
}
#define GST_NAVIGATION_EVENT_HAS_TYPE(event,event_type) \
(gst_navigation_event_get_type (event) == GST_NAVIGATION_EVENT_ ## event_type)
/**
* gst_navigation_event_get_type:
* @event: A #GstEvent to inspect.
*
* Inspect a #GstEvent and return the #GstNavigationEventType of the event, or
* #GST_NAVIGATION_EVENT_INVALID if the event is not a #GstNavigation event.
*/
GstNavigationEventType
gst_navigation_event_get_type (GstEvent * event)
{
const GstStructure *s;
const gchar *e_type;
if (event == NULL || GST_EVENT_TYPE (event) != GST_EVENT_NAVIGATION)
return GST_NAVIGATION_EVENT_INVALID;
s = gst_event_get_structure (event);
if (s == NULL || !gst_structure_has_name (s, GST_NAVIGATION_EVENT_NAME))
return GST_NAVIGATION_EVENT_INVALID;
e_type = gst_structure_get_string (s, "event");
if (e_type == NULL)
return GST_NAVIGATION_EVENT_INVALID;
if (g_str_equal (e_type, "mouse-button-press"))
return GST_NAVIGATION_EVENT_MOUSE_BUTTON_PRESS;
else if (g_str_equal (e_type, "mouse-button-release"))
return GST_NAVIGATION_EVENT_MOUSE_BUTTON_RELEASE;
else if (g_str_equal (e_type, "mouse-move"))
return GST_NAVIGATION_EVENT_MOUSE_MOVE;
else if (g_str_equal (e_type, "key-press"))
return GST_NAVIGATION_EVENT_KEY_PRESS;
else if (g_str_equal (e_type, "key-release"))
return GST_NAVIGATION_EVENT_KEY_RELEASE;
else if (g_str_equal (e_type, "command"))
return GST_NAVIGATION_EVENT_COMMAND;
return GST_NAVIGATION_EVENT_INVALID;
}
/**
* gst_navigation_event_parse_key_event:
* @event: A #GstEvent to inspect.
* @key: (out) (optional) (transfer none): A pointer to a location to receive
* the string identifying the key press. The returned string is owned by the
* event, and valid only until the event is unreffed.
*/
gboolean
gst_navigation_event_parse_key_event (GstEvent * event, const gchar ** key)
{
GstNavigationEventType e_type;
const GstStructure *s;
e_type = gst_navigation_event_get_type (event);
g_return_val_if_fail (e_type == GST_NAVIGATION_EVENT_KEY_PRESS ||
e_type == GST_NAVIGATION_EVENT_KEY_RELEASE, FALSE);
if (key) {
s = gst_event_get_structure (event);
*key = gst_structure_get_string (s, "key");
if (*key == NULL)
return FALSE;
}
return TRUE;
}
/**
* gst_navigation_event_parse_mouse_button_event:
* @event: A #GstEvent to inspect.
* @button: (out) (optional): Pointer to a gint that will receive the button
* number associated with the event.
* @x: (out) (optional): Pointer to a gdouble to receive the x coordinate of the
* mouse button event.
* @y: (out) (optional): Pointer to a gdouble to receive the y coordinate of the
* mouse button event.
*
* Retrieve the details of either a #GstNavigation mouse button press event or
* a mouse button release event. Determine which type the event is using
* gst_navigation_event_get_type() to retrieve the #GstNavigationEventType.
*
* Returns: TRUE if the button number and both coordinates could be extracted,
* otherwise FALSE.
*/
gboolean
gst_navigation_event_parse_mouse_button_event (GstEvent * event, gint * button,
gdouble * x, gdouble * y)
{
GstNavigationEventType e_type;
const GstStructure *s;
gboolean ret = TRUE;
e_type = gst_navigation_event_get_type (event);
g_return_val_if_fail (e_type == GST_NAVIGATION_EVENT_MOUSE_BUTTON_PRESS ||
e_type == GST_NAVIGATION_EVENT_MOUSE_BUTTON_RELEASE, FALSE);
s = gst_event_get_structure (event);
if (x)
ret &= gst_structure_get_double (s, "pointer_x", x);
if (y)
ret &= gst_structure_get_double (s, "pointer_y", y);
if (button)
ret &= gst_structure_get_int (s, "button", button);
WARN_IF_FAIL (ret, "Couldn't extract details from mouse button event");
return ret;
}
/**
* gst_navigation_event_parse_mouse_move_event:
* @event: A #GstEvent to inspect.
* @x: (out) (optional): Pointer to a gdouble to receive the x coordinate of the
* mouse movement.
* @y: (out) (optional): Pointer to a gdouble to receive the y coordinate of the
* mouse movement.
*
* Inspect a #GstNavigation mouse movement event and extract the coordinates
* of the event.
*
* Returns: TRUE if both coordinates could be extracted, otherwise FALSE.
*/
gboolean
gst_navigation_event_parse_mouse_move_event (GstEvent * event, gdouble * x,
gdouble * y)
{
const GstStructure *s;
gboolean ret = TRUE;
g_return_val_if_fail (GST_NAVIGATION_EVENT_HAS_TYPE (event, MOUSE_MOVE),
FALSE);
s = gst_event_get_structure (event);
if (x)
ret &= gst_structure_get_double (s, "pointer_x", x);
if (y)
ret &= gst_structure_get_double (s, "pointer_y", y);
WARN_IF_FAIL (ret, "Couldn't extract positions from mouse move event");
return ret;
}
/**
* gst_navigation_event_parse_command:
* @event: A #GstEvent to inspect.
* @command: (out) (optional): Pointer to GstNavigationCommand to receive the
* type of the navigation event.
*
* Inspect a #GstNavigation command event and retrieve the enum value of the
* associated command.
*
* Returns: TRUE if the navigation command could be extracted, otherwise FALSE.
*/
gboolean
gst_navigation_event_parse_command (GstEvent * event,
GstNavigationCommand * command)
{
const GstStructure *s;
gboolean ret = TRUE;
g_return_val_if_fail (GST_NAVIGATION_EVENT_HAS_TYPE (event, COMMAND), FALSE);
if (command) {
s = gst_event_get_structure (event);
ret = gst_structure_get_uint (s, "command-code", (guint *) command);
WARN_IF_FAIL (ret, "Couldn't extract command code from command event");
}
return ret;
}