|  |  |  | GStreamer 0.10 Core Reference Manual |  | 
|---|---|---|---|---|
| Top | Description | Object Hierarchy | ||||
#include <gst/gst.h>
                    GstGhostPad;
GstPad*             gst_ghost_pad_new                   (const gchar *name,
                                                         GstPad *target);
GstPad*             gst_ghost_pad_new_no_target         (const gchar *name,
                                                         GstPadDirection dir);
GstPad*             gst_ghost_pad_new_from_template     (const gchar *name,
                                                         GstPad *target,
                                                         GstPadTemplate *templ);
GstPad*             gst_ghost_pad_new_no_target_from_template
                                                        (const gchar *name,
                                                         GstPadTemplate *templ);
gboolean            gst_ghost_pad_set_target            (GstGhostPad *gpad,
                                                         GstPad *newtarget);
GstPad*             gst_ghost_pad_get_target            (GstGhostPad *gpad);
gboolean            gst_ghost_pad_construct             (GstGhostPad *gpad);
GhostPads are useful when organizing pipelines with GstBin like elements. The idea here is to create hierarchical element graphs. The bin element contains a sub-graph. Now one would like to treat the bin-element like any other GstElement. This is where GhostPads come into play. A GhostPad acts as a proxy for another pad. Thus the bin can have sink and source ghost-pads that are associated with sink and source pads of the child elements.
If the target pad is known at creation time, gst_ghost_pad_new() is the
function to use to get a ghost-pad. Otherwise one can use gst_ghost_pad_new_no_target()
to create the ghost-pad and use gst_ghost_pad_set_target() to establish the
association later on.
Note that GhostPads add overhead to the data processing of a pipeline.
Last reviewed on 2005-11-18 (0.9.5)
GstPad* gst_ghost_pad_new (const gchar *name,GstPad *target);
Create a new ghostpad with target as the target. The direction will be taken
from the target pad. target must be unlinked.
Will ref the target.
| 
 | the name of the new pad, or NULL to assign a default name. | 
| 
 | the pad to ghost. | 
| Returns : | a new GstPad, or NULL in case of an error. | 
GstPad* gst_ghost_pad_new_no_target (const gchar *name,GstPadDirection dir);
Create a new ghostpad without a target with the given direction.
A target can be set on the ghostpad later with the
gst_ghost_pad_set_target() function.
The created ghostpad will not have a padtemplate.
| 
 | the name of the new pad, or NULL to assign a default name. | 
| 
 | the direction of the ghostpad | 
| Returns : | a new GstPad, or NULL in case of an error. | 
GstPad* gst_ghost_pad_new_from_template (const gchar *name,GstPad *target,GstPadTemplate *templ);
Create a new ghostpad with target as the target. The direction will be taken
from the target pad. The template used on the ghostpad will be template.
Will ref the target.
| 
 | the name of the new pad, or NULL to assign a default name. | 
| 
 | the pad to ghost. | 
| 
 | the GstPadTemplate to use on the ghostpad. | 
| Returns : | a new GstPad, or NULL in case of an error. | 
Since 0.10.10
GstPad* gst_ghost_pad_new_no_target_from_template (const gchar *name,GstPadTemplate *templ);
Create a new ghostpad based on templ, without setting a target. The
direction will be taken from the templ.
| 
 | the name of the new pad, or NULL to assign a default name. | 
| 
 | the GstPadTemplate to create the ghostpad from. | 
| Returns : | a new GstPad, or NULL in case of an error. | 
Since 0.10.10
gboolean gst_ghost_pad_set_target (GstGhostPad *gpad,GstPad *newtarget);
Set the new target of the ghostpad gpad. Any existing target
is unlinked and links to the new target are established. if newtarget is
NULL the target will be cleared.
| 
 | the GstGhostPad | 
| 
 | the new pad target | 
| Returns : | TRUE if the new target could be set. This function can return FALSE when the internal pads could not be linked. | 
GstPad*             gst_ghost_pad_get_target            (GstGhostPad *gpad);
Get the target pad of gpad. Unref target pad after usage.
| 
 | the GstGhostPad | 
| Returns : | the target GstPad, can be NULL if the ghostpad has no target set. Unref target pad after usage. | 
gboolean            gst_ghost_pad_construct             (GstGhostPad *gpad);
Finish initialization of a newly allocated ghost pad.
This function is most useful in language bindings and when subclassing
GstGhostPad; plugin and application developers normally will not call this
function. Call this function directly after a call to g_object_new
(GST_TYPE_GHOST_PAD, "direction", dir, ..., NULL).
Since 0.10.22