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/* Gnome-Streamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_EXAMPLE_H__
#define __GST_EXAMPLE_H__
#include <gst/gst.h>
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/* This is the definition of the element's object structure. */
typedef struct _GstExample GstExample;
/* The structure itself is derived from GstElement, as can be seen by the
* fact that there's a complete instance of the GstElement structure at
* the beginning of the object. This allows the element to be cast to
* an Element or even an Object.
*/
struct _GstExample {
GstElement element;
/* We need to keep track of our pads, so we do so here. */
GstPad *sinkpad,*srcpad;
/* We'll use this to decide whether to do anything to the data we get. */
gboolean active;
};
/* The other half of the object is its class. The class also derives from
* the same parent, though it must be the class structure this time.
* Function pointers for polymophic methods and signals are placed in this
* structure. */
typedef struct _GstExampleClass GstExampleClass;
struct _GstExampleClass {
GstElementClass parent_class;
/* signals */
void (*asdf) (GstElement *element, GstExample *example);
};
/* Five standard preprocessing macros are used in the Gtk+ object system.
* The first uses the object's _get_type function to return the GtkType
* of the object.
*/
#define GST_TYPE_EXAMPLE \
(gst_example_get_type())
/* The second is a checking cast to the correct type. If the object passed
* is not the right type, a warning will be generated on stderr.
*/
#define GST_EXAMPLE(obj) \
(GTK_CHECK_CAST((obj),GST_TYPE_EXAMPLE,GstExample))
/* The third is a checking cast of the class instead of the object. */
#define GST_EXAMPLE_CLASS(klass) \
(GTK_CHECK_CLASS_CAST((klass),GST_TYPE_EXAMPLE,GstExample))
/* The last two simply check to see if the passed pointer is an object or
* class of the correct type. */
#define GST_IS_EXAMPLE(obj) \
(GTK_CHECK_TYPE((obj),GST_TYPE_EXAMPLE))
#define GST_IS_EXAMPLE_CLASS(obj) \
(GTK_CHECK_CLASS_TYPE((klass),GST_TYPE_EXAMPLE))
/* This is the only prototype needed, because it is used in the above
* GST_TYPE_EXAMPLE macro.
*/
GtkType gst_example_get_type(void);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __GST_EXAMPLE_H__ */
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