src/cairo-raster-source-pattern.c - third_party/cairo - Git at Google

 /* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
 /* cairo - a vector graphics library with display and print output
  *
  * Copyright © 2011 Intel Corporation
  *
  * This library is free software; you can redistribute it and/or
  * modify it either under the terms of the GNU Lesser General Public
  * License version 2.1 as published by the Free Software Foundation
  * (the "LGPL") or, at your option, under the terms of the Mozilla
  * Public License Version 1.1 (the "MPL"). If you do not alter this
  * notice, a recipient may use your version of this file under either
  * the MPL or the LGPL.
  *
  * You should have received a copy of the LGPL along with this library
  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
  * You should have received a copy of the MPL along with this library
  * in the file COPYING-MPL-1.1
  *
  * The contents of this file are subject to the Mozilla Public License
  * Version 1.1 (the "License"); you may not use this file except in
  * compliance with the License. You may obtain a copy of the License at
  * http://www.mozilla.org/MPL/
  *
  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
  * the specific language governing rights and limitations.
  *
  * The Original Code is the cairo graphics library.
  *
  * The Initial Developer of the Original Code is Red Hat, Inc.
  *
  * Contributor(s):
  *	Chris Wilson <chris@chris-wilson.co.uk>
  */

 #include "cairoint.h"
 #include "cairo-error-private.h"
 #include "cairo-pattern-private.h"

 /**
  * SECTION:cairo-raster-source
  * @Title: Raster Sources
  * @Short_Description: Supplying arbitrary image data
  * @See_Also: #cairo_pattern_t
  *
  * The raster source provides the ability to supply arbitrary pixel data
  * whilst rendering. The pixels are queried at the time of rasterisation
  * by means of user callback functions, allowing for the ultimate
  * flexibility. For example, in handling compressed image sources, you
  * may keep a MRU cache of decompressed images and decompress sources on the
  * fly and discard old ones to conserve memory.
  *
  * For the raster source to be effective, you must at least specify
  * the acquire and release callbacks which are used to retrieve the pixel
  * data for the region of interest and demark when it can be freed afterwards.
  * Other callbacks are provided for when the pattern is copied temporarily
  * during rasterisation, or more permanently as a snapshot in order to keep
  * the pixel data available for printing.
  **/

 cairo_surface_t *
 _cairo_raster_source_pattern_acquire (const cairo_pattern_t *abstract_pattern,
 				      cairo_surface_t *target,
 				      const cairo_rectangle_int_t *extents)
 {
     cairo_raster_source_pattern_t *pattern =
 	(cairo_raster_source_pattern_t *) abstract_pattern;

     if (pattern->acquire == NULL)
 	return NULL;

     if (extents == NULL)
 	extents = &pattern->extents;

     return pattern->acquire (&pattern->base, pattern->user_data,
 			     target, extents);
 }

 void
 _cairo_raster_source_pattern_release (const cairo_pattern_t *abstract_pattern,
 				      cairo_surface_t *surface)
 {
     cairo_raster_source_pattern_t *pattern =
 	(cairo_raster_source_pattern_t *) abstract_pattern;

     if (pattern->release == NULL)
 	return;

     pattern->release (&pattern->base, pattern->user_data, surface);
 }

 cairo_status_t
 _cairo_raster_source_pattern_init_copy (cairo_pattern_t *abstract_pattern,
 					const cairo_pattern_t *other)
 {
     cairo_raster_source_pattern_t *pattern =
 	(cairo_raster_source_pattern_t *) abstract_pattern;
     cairo_status_t status;

     VG (VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_raster_source_pattern_t)));
     memcpy(pattern, other, sizeof (cairo_raster_source_pattern_t));

     status = CAIRO_STATUS_SUCCESS;
     if (pattern->copy)
 	status = pattern->copy (&pattern->base, pattern->user_data, other);

     return status;
 }

 cairo_status_t
 _cairo_raster_source_pattern_snapshot (cairo_pattern_t *abstract_pattern)
 {
     cairo_raster_source_pattern_t *pattern =
 	(cairo_raster_source_pattern_t *) abstract_pattern;

     if (pattern->snapshot == NULL)
 	return CAIRO_STATUS_SUCCESS;

     return pattern->snapshot (&pattern->base, pattern->user_data);
 }

 void
 _cairo_raster_source_pattern_finish (cairo_pattern_t *abstract_pattern)
 {
     cairo_raster_source_pattern_t *pattern =
 	(cairo_raster_source_pattern_t *) abstract_pattern;

     if (pattern->finish == NULL)
 	return;

     pattern->finish (&pattern->base, pattern->user_data);
 }

 /* Public interface */

 /**
  * cairo_pattern_create_raster_source:
  * @user_data: the user data to be passed to all callbacks
  * @content: content type for the pixel data that will be returned. Knowing
  * the content type ahead of time is used for analysing the operation and
  * picking the appropriate rendering path.
  * @width: maximum size of the sample area
  * @height: maximum size of the sample area
  *
  * Creates a new user pattern for providing pixel data.
  *
  * Use the setter functions to associate callbacks with the returned
  * pattern.  The only mandatory callback is acquire.
  *
  * Return value: a newly created #cairo_pattern_t. Free with
  *  cairo_pattern_destroy() when you are done using it.
  *
  * Since: 1.12
  **/
 cairo_pattern_t *
 cairo_pattern_create_raster_source (void *user_data,
 				    cairo_content_t content,
 				    int width, int height)
 {
     cairo_raster_source_pattern_t *pattern;

     CAIRO_MUTEX_INITIALIZE ();

     if (width < 0 || height < 0)
 	return _cairo_pattern_create_in_error (CAIRO_STATUS_INVALID_SIZE);

     if (! CAIRO_CONTENT_VALID (content))
 	return _cairo_pattern_create_in_error (CAIRO_STATUS_INVALID_CONTENT);

     pattern = calloc (1, sizeof (*pattern));
     if (unlikely (pattern == NULL))
 	return _cairo_pattern_create_in_error (CAIRO_STATUS_NO_MEMORY);

     _cairo_pattern_init (&pattern->base,
 			 CAIRO_PATTERN_TYPE_RASTER_SOURCE);
     CAIRO_REFERENCE_COUNT_INIT (&pattern->base.ref_count, 1);

     pattern->content = content;

     pattern->extents.x = 0;
     pattern->extents.y = 0;
     pattern->extents.width  = width;
     pattern->extents.height = height;

     pattern->user_data = user_data;

     return &pattern->base;
 }

 /**
  * cairo_raster_source_pattern_set_callback_data:
  * @pattern: the pattern to update
  * @data: the user data to be passed to all callbacks
  *
  * Updates the user data that is provided to all callbacks.
  *
  * Since: 1.12
  **/
 void
 cairo_raster_source_pattern_set_callback_data (cairo_pattern_t *abstract_pattern,
 					       void *data)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     pattern->user_data = data;
 }

 /**
  * cairo_raster_source_pattern_get_callback_data:
  * @pattern: the pattern to update
  *
  * Queries the current user data.
  *
  * Return value: the current user-data passed to each callback
  *
  * Since: 1.12
  **/
 void *
 cairo_raster_source_pattern_get_callback_data (cairo_pattern_t *abstract_pattern)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return NULL;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     return pattern->user_data;
 }

 /**
  * cairo_raster_source_pattern_set_acquire:
  * @pattern: the pattern to update
  * @acquire: acquire callback
  * @release: release callback
  *
  * Specifies the callbacks used to generate the image surface for a rendering
  * operation (acquire) and the function used to cleanup that surface afterwards.
  *
  * The @acquire callback should create a surface (preferably an image
  * surface created to match the target using
  * cairo_surface_create_similar_image()) that defines at least the region
  * of interest specified by extents. The surface is allowed to be the entire
  * sample area, but if it does contain a subsection of the sample area,
  * the surface extents should be provided by setting the device offset (along
  * with its width and height) using cairo_surface_set_device_offset().
  *
  * Since: 1.12
  **/
 void
 cairo_raster_source_pattern_set_acquire (cairo_pattern_t *abstract_pattern,
 					 cairo_raster_source_acquire_func_t acquire,
 					 cairo_raster_source_release_func_t release)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     pattern->acquire = acquire;
     pattern->release = release;
 }

 /**
  * cairo_raster_source_pattern_get_acquire:
  * @pattern: the pattern to query
  * @acquire: return value for the current acquire callback
  * @release: return value for the current release callback
  *
  * Queries the current acquire and release callbacks.
  *
  * Since: 1.12
  **/
 void
 cairo_raster_source_pattern_get_acquire (cairo_pattern_t *abstract_pattern,
 					 cairo_raster_source_acquire_func_t *acquire,
 					 cairo_raster_source_release_func_t *release)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     if (acquire)
 	*acquire = pattern->acquire;
     if (release)
 	*release = pattern->release;
 }

 /**
  * cairo_raster_source_pattern_set_snapshot:
  * @pattern: the pattern to update
  * @snapshot: snapshot callback
  *
  * Sets the callback that will be used whenever a snapshot is taken of the
  * pattern, that is whenever the current contents of the pattern should be
  * preserved for later use. This is typically invoked whilst printing.
  *
  * Since: 1.12
  **/
 void
 cairo_raster_source_pattern_set_snapshot (cairo_pattern_t *abstract_pattern,
 					  cairo_raster_source_snapshot_func_t snapshot)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     pattern->snapshot = snapshot;
 }

 /**
  * cairo_raster_source_pattern_get_snapshot:
  * @pattern: the pattern to query
  *
  * Queries the current snapshot callback.
  *
  * Return value: the current snapshot callback
  *
  * Since: 1.12
  **/
 cairo_raster_source_snapshot_func_t
 cairo_raster_source_pattern_get_snapshot (cairo_pattern_t *abstract_pattern)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return NULL;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     return pattern->snapshot;
 }

 /**
  * cairo_raster_source_pattern_set_copy:
  * @pattern: the pattern to update
  * @copy: the copy callback
  *
  * Updates the copy callback which is used whenever a temporary copy of the
  * pattern is taken.
  *
  * Since: 1.12
  **/
 void
 cairo_raster_source_pattern_set_copy (cairo_pattern_t *abstract_pattern,
 				      cairo_raster_source_copy_func_t copy)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     pattern->copy = copy;
 }

 /**
  * cairo_raster_source_pattern_get_copy:
  * @pattern: the pattern to query
  *
  * Queries the current copy callback.
  *
  * Return value: the current copy callback
  *
  * Since: 1.12
  **/
 cairo_raster_source_copy_func_t
 cairo_raster_source_pattern_get_copy (cairo_pattern_t *abstract_pattern)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return NULL;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     return pattern->copy;
 }

 /**
  * cairo_raster_source_pattern_set_finish:
  * @pattern: the pattern to update
  * @finish: the finish callback
  *
  * Updates the finish callback which is used whenever a pattern (or a copy
  * thereof) will no longer be used.
  *
  * Since: 1.12
  **/
 void
 cairo_raster_source_pattern_set_finish (cairo_pattern_t *abstract_pattern,
 					cairo_raster_source_finish_func_t finish)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     pattern->finish = finish;
 }

 /**
  * cairo_raster_source_pattern_get_finish:
  * @pattern: the pattern to query
  *
  * Queries the current finish callback.
  *
  * Return value: the current finish callback
  *
  * Since: 1.12
  **/
 cairo_raster_source_finish_func_t
 cairo_raster_source_pattern_get_finish (cairo_pattern_t *abstract_pattern)
 {
     cairo_raster_source_pattern_t *pattern;

     if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
 	return NULL;

     pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
     return pattern->finish;
 }
	/* -- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -- */
	/* cairo - a vector graphics library with display and print output
	*
	* Copyright © 2011 Intel Corporation
	*
	* This library is free software; you can redistribute it and/or
	* modify it either under the terms of the GNU Lesser General Public
	* License version 2.1 as published by the Free Software Foundation
	* (the "LGPL") or, at your option, under the terms of the Mozilla
	* Public License Version 1.1 (the "MPL"). If you do not alter this
	* notice, a recipient may use your version of this file under either
	* the MPL or the LGPL.
	*
	* You should have received a copy of the LGPL along with this library
	* in the file COPYING-LGPL-2.1; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
	* You should have received a copy of the MPL along with this library
	* in the file COPYING-MPL-1.1
	*
	* The contents of this file are subject to the Mozilla Public License
	* Version 1.1 (the "License"); you may not use this file except in
	* compliance with the License. You may obtain a copy of the License at
	* http://www.mozilla.org/MPL/
	*
	* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
	* OF ANY KIND, either express or implied. See the LGPL or the MPL for
	* the specific language governing rights and limitations.
	*
	* The Original Code is the cairo graphics library.
	*
	* The Initial Developer of the Original Code is Red Hat, Inc.
	*
	* Contributor(s):
	* Chris Wilson <chris@chris-wilson.co.uk>
	*/

	#include "cairoint.h"
	#include "cairo-error-private.h"
	#include "cairo-pattern-private.h"

	/**
	* SECTION:cairo-raster-source
	* @Title: Raster Sources
	* @Short_Description: Supplying arbitrary image data
	* @See_Also: #cairo_pattern_t
	*
	* The raster source provides the ability to supply arbitrary pixel data
	* whilst rendering. The pixels are queried at the time of rasterisation
	* by means of user callback functions, allowing for the ultimate
	* flexibility. For example, in handling compressed image sources, you
	* may keep a MRU cache of decompressed images and decompress sources on the
	* fly and discard old ones to conserve memory.
	*
	* For the raster source to be effective, you must at least specify
	* the acquire and release callbacks which are used to retrieve the pixel
	* data for the region of interest and demark when it can be freed afterwards.
	* Other callbacks are provided for when the pattern is copied temporarily
	* during rasterisation, or more permanently as a snapshot in order to keep
	* the pixel data available for printing.
	**/

	cairo_surface_t *
	_cairo_raster_source_pattern_acquire (const cairo_pattern_t *abstract_pattern,
	cairo_surface_t *target,
	const cairo_rectangle_int_t *extents)
	{
	cairo_raster_source_pattern_t *pattern =
	(cairo_raster_source_pattern_t *) abstract_pattern;

	if (pattern->acquire == NULL)
	return NULL;

	if (extents == NULL)
	extents = &pattern->extents;

	return pattern->acquire (&pattern->base, pattern->user_data,
	target, extents);
	}

	void
	_cairo_raster_source_pattern_release (const cairo_pattern_t *abstract_pattern,
	cairo_surface_t *surface)
	{
	cairo_raster_source_pattern_t *pattern =
	(cairo_raster_source_pattern_t *) abstract_pattern;

	if (pattern->release == NULL)
	return;

	pattern->release (&pattern->base, pattern->user_data, surface);
	}

	cairo_status_t
	_cairo_raster_source_pattern_init_copy (cairo_pattern_t *abstract_pattern,
	const cairo_pattern_t *other)
	{
	cairo_raster_source_pattern_t *pattern =
	(cairo_raster_source_pattern_t *) abstract_pattern;
	cairo_status_t status;

	VG (VALGRIND_MAKE_MEM_UNDEFINED (pattern, sizeof (cairo_raster_source_pattern_t)));
	memcpy(pattern, other, sizeof (cairo_raster_source_pattern_t));

	status = CAIRO_STATUS_SUCCESS;
	if (pattern->copy)
	status = pattern->copy (&pattern->base, pattern->user_data, other);

	return status;
	}

	cairo_status_t
	_cairo_raster_source_pattern_snapshot (cairo_pattern_t *abstract_pattern)
	{
	cairo_raster_source_pattern_t *pattern =
	(cairo_raster_source_pattern_t *) abstract_pattern;

	if (pattern->snapshot == NULL)
	return CAIRO_STATUS_SUCCESS;

	return pattern->snapshot (&pattern->base, pattern->user_data);
	}

	void
	_cairo_raster_source_pattern_finish (cairo_pattern_t *abstract_pattern)
	{
	cairo_raster_source_pattern_t *pattern =
	(cairo_raster_source_pattern_t *) abstract_pattern;

	if (pattern->finish == NULL)
	return;

	pattern->finish (&pattern->base, pattern->user_data);
	}

	/* Public interface */

	/**
	* cairo_pattern_create_raster_source:
	* @user_data: the user data to be passed to all callbacks
	* @content: content type for the pixel data that will be returned. Knowing
	* the content type ahead of time is used for analysing the operation and
	* picking the appropriate rendering path.
	* @width: maximum size of the sample area
	* @height: maximum size of the sample area
	*
	* Creates a new user pattern for providing pixel data.
	*
	* Use the setter functions to associate callbacks with the returned
	* pattern. The only mandatory callback is acquire.
	*
	* Return value: a newly created #cairo_pattern_t. Free with
	* cairo_pattern_destroy() when you are done using it.
	*
	* Since: 1.12
	**/
	cairo_pattern_t *
	cairo_pattern_create_raster_source (void *user_data,
	cairo_content_t content,
	int width, int height)
	{
	cairo_raster_source_pattern_t *pattern;

	CAIRO_MUTEX_INITIALIZE ();

	if (width < 0 \|\| height < 0)
	return _cairo_pattern_create_in_error (CAIRO_STATUS_INVALID_SIZE);

	if (! CAIRO_CONTENT_VALID (content))
	return _cairo_pattern_create_in_error (CAIRO_STATUS_INVALID_CONTENT);

	pattern = calloc (1, sizeof (*pattern));
	if (unlikely (pattern == NULL))
	return _cairo_pattern_create_in_error (CAIRO_STATUS_NO_MEMORY);

	_cairo_pattern_init (&pattern->base,
	CAIRO_PATTERN_TYPE_RASTER_SOURCE);
	CAIRO_REFERENCE_COUNT_INIT (&pattern->base.ref_count, 1);

	pattern->content = content;

	pattern->extents.x = 0;
	pattern->extents.y = 0;
	pattern->extents.width = width;
	pattern->extents.height = height;

	pattern->user_data = user_data;

	return &pattern->base;
	}

	/**
	* cairo_raster_source_pattern_set_callback_data:
	* @pattern: the pattern to update
	* @data: the user data to be passed to all callbacks
	*
	* Updates the user data that is provided to all callbacks.
	*
	* Since: 1.12
	**/
	void
	cairo_raster_source_pattern_set_callback_data (cairo_pattern_t *abstract_pattern,
	void *data)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	pattern->user_data = data;
	}

	/**
	* cairo_raster_source_pattern_get_callback_data:
	* @pattern: the pattern to update
	*
	* Queries the current user data.
	*
	* Return value: the current user-data passed to each callback
	*
	* Since: 1.12
	**/
	void *
	cairo_raster_source_pattern_get_callback_data (cairo_pattern_t *abstract_pattern)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return NULL;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	return pattern->user_data;
	}

	/**
	* cairo_raster_source_pattern_set_acquire:
	* @pattern: the pattern to update
	* @acquire: acquire callback
	* @release: release callback
	*
	* Specifies the callbacks used to generate the image surface for a rendering
	* operation (acquire) and the function used to cleanup that surface afterwards.
	*
	* The @acquire callback should create a surface (preferably an image
	* surface created to match the target using
	* cairo_surface_create_similar_image()) that defines at least the region
	* of interest specified by extents. The surface is allowed to be the entire
	* sample area, but if it does contain a subsection of the sample area,
	* the surface extents should be provided by setting the device offset (along
	* with its width and height) using cairo_surface_set_device_offset().
	*
	* Since: 1.12
	**/
	void
	cairo_raster_source_pattern_set_acquire (cairo_pattern_t *abstract_pattern,
	cairo_raster_source_acquire_func_t acquire,
	cairo_raster_source_release_func_t release)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	pattern->acquire = acquire;
	pattern->release = release;
	}

	/**
	* cairo_raster_source_pattern_get_acquire:
	* @pattern: the pattern to query
	* @acquire: return value for the current acquire callback
	* @release: return value for the current release callback
	*
	* Queries the current acquire and release callbacks.
	*
	* Since: 1.12
	**/
	void
	cairo_raster_source_pattern_get_acquire (cairo_pattern_t *abstract_pattern,
	cairo_raster_source_acquire_func_t *acquire,
	cairo_raster_source_release_func_t *release)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	if (acquire)
	*acquire = pattern->acquire;
	if (release)
	*release = pattern->release;
	}

	/**
	* cairo_raster_source_pattern_set_snapshot:
	* @pattern: the pattern to update
	* @snapshot: snapshot callback
	*
	* Sets the callback that will be used whenever a snapshot is taken of the
	* pattern, that is whenever the current contents of the pattern should be
	* preserved for later use. This is typically invoked whilst printing.
	*
	* Since: 1.12
	**/
	void
	cairo_raster_source_pattern_set_snapshot (cairo_pattern_t *abstract_pattern,
	cairo_raster_source_snapshot_func_t snapshot)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	pattern->snapshot = snapshot;
	}

	/**
	* cairo_raster_source_pattern_get_snapshot:
	* @pattern: the pattern to query
	*
	* Queries the current snapshot callback.
	*
	* Return value: the current snapshot callback
	*
	* Since: 1.12
	**/
	cairo_raster_source_snapshot_func_t
	cairo_raster_source_pattern_get_snapshot (cairo_pattern_t *abstract_pattern)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return NULL;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	return pattern->snapshot;
	}

	/**
	* cairo_raster_source_pattern_set_copy:
	* @pattern: the pattern to update
	* @copy: the copy callback
	*
	* Updates the copy callback which is used whenever a temporary copy of the
	* pattern is taken.
	*
	* Since: 1.12
	**/
	void
	cairo_raster_source_pattern_set_copy (cairo_pattern_t *abstract_pattern,
	cairo_raster_source_copy_func_t copy)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	pattern->copy = copy;
	}

	/**
	* cairo_raster_source_pattern_get_copy:
	* @pattern: the pattern to query
	*
	* Queries the current copy callback.
	*
	* Return value: the current copy callback
	*
	* Since: 1.12
	**/
	cairo_raster_source_copy_func_t
	cairo_raster_source_pattern_get_copy (cairo_pattern_t *abstract_pattern)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return NULL;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	return pattern->copy;
	}

	/**
	* cairo_raster_source_pattern_set_finish:
	* @pattern: the pattern to update
	* @finish: the finish callback
	*
	* Updates the finish callback which is used whenever a pattern (or a copy
	* thereof) will no longer be used.
	*
	* Since: 1.12
	**/
	void
	cairo_raster_source_pattern_set_finish (cairo_pattern_t *abstract_pattern,
	cairo_raster_source_finish_func_t finish)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	pattern->finish = finish;
	}

	/**
	* cairo_raster_source_pattern_get_finish:
	* @pattern: the pattern to query
	*
	* Queries the current finish callback.
	*
	* Return value: the current finish callback
	*
	* Since: 1.12
	**/
	cairo_raster_source_finish_func_t
	cairo_raster_source_pattern_get_finish (cairo_pattern_t *abstract_pattern)
	{
	cairo_raster_source_pattern_t *pattern;

	if (abstract_pattern->type != CAIRO_PATTERN_TYPE_RASTER_SOURCE)
	return NULL;

	pattern = (cairo_raster_source_pattern_t *) abstract_pattern;
	return pattern->finish;
	}