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/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */

/* cairo - a vector graphics library with display and print output

 *

 * Copyright © 2005 Red Hat, Inc.

 *

 * 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):

 *	Owen Taylor 

 *      Vladimir Vukicevic 

 *      Søren Sandmann 

 */

#include "cairoint.h"

#include "cairo-error-private.h"

#include "cairo-region-private.h"

/* XXX need to update pixman headers to be const as appropriate */

#define CONST_CAST (pixman_region32_t *)

/**

 * SECTION:cairo-region

 * @Title: Regions

 * @Short_Description: Representing a pixel-aligned area

 *

 * Regions are a simple graphical data type representing an area of

 * integer-aligned rectangles. They are often used on raster surfaces

 * to track areas of interest, such as change or clip areas.

 **/

static const cairo_region_t _cairo_region_nil = {

    CAIRO_REFERENCE_COUNT_INVALID,	/* ref_count */

    CAIRO_STATUS_NO_MEMORY,		/* status */

};

cairo_region_t *

_cairo_region_create_in_error (cairo_status_t status)

{

    switch (status) {

    case CAIRO_STATUS_NO_MEMORY:

	return (cairo_region_t *) &_cairo_region_nil;

    case CAIRO_STATUS_SUCCESS:

    case CAIRO_STATUS_LAST_STATUS:

	ASSERT_NOT_REACHED;

	/* fall-through */

    case CAIRO_STATUS_SURFACE_TYPE_MISMATCH:

    case CAIRO_STATUS_INVALID_STATUS:

    case CAIRO_STATUS_INVALID_CONTENT:

    case CAIRO_STATUS_INVALID_FORMAT:

    case CAIRO_STATUS_INVALID_VISUAL:

    case CAIRO_STATUS_READ_ERROR:

    case CAIRO_STATUS_WRITE_ERROR:

    case CAIRO_STATUS_FILE_NOT_FOUND:

    case CAIRO_STATUS_TEMP_FILE_ERROR:

    case CAIRO_STATUS_INVALID_STRIDE:

    case CAIRO_STATUS_INVALID_SIZE:

    case CAIRO_STATUS_DEVICE_TYPE_MISMATCH:

    case CAIRO_STATUS_DEVICE_ERROR:

    case CAIRO_STATUS_INVALID_RESTORE:

    case CAIRO_STATUS_INVALID_POP_GROUP:

    case CAIRO_STATUS_NO_CURRENT_POINT:

    case CAIRO_STATUS_INVALID_MATRIX:

    case CAIRO_STATUS_NULL_POINTER:

    case CAIRO_STATUS_INVALID_STRING:

    case CAIRO_STATUS_INVALID_PATH_DATA:

    case CAIRO_STATUS_SURFACE_FINISHED:

    case CAIRO_STATUS_PATTERN_TYPE_MISMATCH:

    case CAIRO_STATUS_INVALID_DASH:

    case CAIRO_STATUS_INVALID_DSC_COMMENT:

    case CAIRO_STATUS_INVALID_INDEX:

    case CAIRO_STATUS_CLIP_NOT_REPRESENTABLE:

    case CAIRO_STATUS_FONT_TYPE_MISMATCH:

    case CAIRO_STATUS_USER_FONT_IMMUTABLE:

    case CAIRO_STATUS_USER_FONT_ERROR:

    case CAIRO_STATUS_NEGATIVE_COUNT:

    case CAIRO_STATUS_INVALID_CLUSTERS:

    case CAIRO_STATUS_INVALID_SLANT:

    case CAIRO_STATUS_INVALID_WEIGHT:

    case CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED:

    case CAIRO_STATUS_INVALID_MESH_CONSTRUCTION:

    case CAIRO_STATUS_DEVICE_FINISHED:

    default:

	_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);

	return (cairo_region_t *) &_cairo_region_nil;

    }

}

/**

 * _cairo_region_set_error:

 * @region: a region

 * @status: a status value indicating an error

 *

 * Atomically sets region->status to @status and calls _cairo_error;

 * Does nothing if status is %CAIRO_STATUS_SUCCESS or any of the internal

 * status values.

 *

 * All assignments of an error status to region->status should happen

 * through _cairo_region_set_error(). Note that due to the nature of

 * the atomic operation, it is not safe to call this function on the

 * nil objects.

 *

 * The purpose of this function is to allow the user to set a

 * breakpoint in _cairo_error() to generate a stack trace for when the

 * user causes cairo to detect an error.

 *

 * Return value: the error status.

 **/

static cairo_status_t

_cairo_region_set_error (cairo_region_t *region,

			 cairo_status_t status)

{

    if (status == CAIRO_STATUS_SUCCESS)

        return CAIRO_STATUS_SUCCESS;

    /* Don't overwrite an existing error. This preserves the first

     * error, which is the most significant. */

    _cairo_status_set_error (®ion->status, status);

    return _cairo_error (status);

}

void

_cairo_region_init (cairo_region_t *region)

{

    VG (VALGRIND_MAKE_MEM_UNDEFINED (region, sizeof (cairo_region_t)));

    region->status = CAIRO_STATUS_SUCCESS;

    CAIRO_REFERENCE_COUNT_INIT (®ion->ref_count, 0);

    pixman_region32_init (®ion->rgn);

}

void

_cairo_region_init_rectangle (cairo_region_t *region,

			      const cairo_rectangle_int_t *rectangle)

{

    VG (VALGRIND_MAKE_MEM_UNDEFINED (region, sizeof (cairo_region_t)));

    region->status = CAIRO_STATUS_SUCCESS;

    CAIRO_REFERENCE_COUNT_INIT (®ion->ref_count, 0);

    pixman_region32_init_rect (®ion->rgn,

			       rectangle->x, rectangle->y,

			       rectangle->width, rectangle->height);

}

void

_cairo_region_fini (cairo_region_t *region)

{

    assert (! CAIRO_REFERENCE_COUNT_HAS_REFERENCE (®ion->ref_count));

    pixman_region32_fini (®ion->rgn);

    VG (VALGRIND_MAKE_MEM_NOACCESS (region, sizeof (cairo_region_t)));

}

/**

 * cairo_region_create:

 *

 * Allocates a new empty region object.

 *

 * Return value: A newly allocated #cairo_region_t. Free with

 *   cairo_region_destroy(). This function always returns a

 *   valid pointer; if memory cannot be allocated, then a special

 *   error object is returned where all operations on the object do nothing.

 *   You can check for this with cairo_region_status().

 *

 * Since: 1.10

 **/

cairo_region_t *

cairo_region_create (void)

{

    cairo_region_t *region;

    region = _cairo_malloc (sizeof (cairo_region_t));

    if (region == NULL)

	return (cairo_region_t *) &_cairo_region_nil;

    region->status = CAIRO_STATUS_SUCCESS;

    CAIRO_REFERENCE_COUNT_INIT (®ion->ref_count, 1);

    pixman_region32_init (®ion->rgn);

    return region;

}

slim_hidden_def (cairo_region_create);

/**

 * cairo_region_create_rectangles:

 * @rects: an array of @count rectangles

 * @count: number of rectangles

 *

 * Allocates a new region object containing the union of all given @rects.

 *

 * Return value: A newly allocated #cairo_region_t. Free with

 *   cairo_region_destroy(). This function always returns a

 *   valid pointer; if memory cannot be allocated, then a special

 *   error object is returned where all operations on the object do nothing.

 *   You can check for this with cairo_region_status().

 *

 * Since: 1.10

 **/

cairo_region_t *

cairo_region_create_rectangles (const cairo_rectangle_int_t *rects,

				int count)

{

    pixman_box32_t stack_pboxes[CAIRO_STACK_ARRAY_LENGTH (pixman_box32_t)];

    pixman_box32_t *pboxes = stack_pboxes;

    cairo_region_t *region;

    int i;

    region = _cairo_malloc (sizeof (cairo_region_t));

    if (unlikely (region == NULL))

	return _cairo_region_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

    CAIRO_REFERENCE_COUNT_INIT (®ion->ref_count, 1);

    region->status = CAIRO_STATUS_SUCCESS;

    if (count == 1) {

	pixman_region32_init_rect (®ion->rgn,

				   rects->x, rects->y,

				   rects->width, rects->height);

	return region;

    }

    if (count > ARRAY_LENGTH (stack_pboxes)) {

	pboxes = _cairo_malloc_ab (count, sizeof (pixman_box32_t));

	if (unlikely (pboxes == NULL)) {

	    free (region);

	    return _cairo_region_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

	}

    }

    for (i = 0; i < count; i++) {

	pboxes[i].x1 = rects[i].x;

	pboxes[i].y1 = rects[i].y;

	pboxes[i].x2 = rects[i].x + rects[i].width;

	pboxes[i].y2 = rects[i].y + rects[i].height;

    }

    i = pixman_region32_init_rects (®ion->rgn, pboxes, count);

    if (pboxes != stack_pboxes)

	free (pboxes);

    if (unlikely (i == 0)) {

	free (region);

	return _cairo_region_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

    }

    return region;

}

slim_hidden_def (cairo_region_create_rectangles);

cairo_region_t *

_cairo_region_create_from_boxes (const cairo_box_t *boxes, int count)

{

    cairo_region_t *region;

    region = _cairo_malloc (sizeof (cairo_region_t));

    if (unlikely (region == NULL))

	return _cairo_region_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

    CAIRO_REFERENCE_COUNT_INIT (®ion->ref_count, 1);

    region->status = CAIRO_STATUS_SUCCESS;

    if (! pixman_region32_init_rects (®ion->rgn,

				      (pixman_box32_t *)boxes, count)) {

	free (region);

	return _cairo_region_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

    }

    return region;

}

cairo_box_t *

_cairo_region_get_boxes (const cairo_region_t *region, int *nbox)

{

    if (region->status) {

	nbox = 0;

	return NULL;

    }

    return (cairo_box_t *) pixman_region32_rectangles (CONST_CAST ®ion->rgn, nbox);

}

/**

 * cairo_region_create_rectangle:

 * @rectangle: a #cairo_rectangle_int_t

 *

 * Allocates a new region object containing @rectangle.

 *

 * Return value: A newly allocated #cairo_region_t. Free with

 *   cairo_region_destroy(). This function always returns a

 *   valid pointer; if memory cannot be allocated, then a special

 *   error object is returned where all operations on the object do nothing.

 *   You can check for this with cairo_region_status().

 *

 * Since: 1.10

 **/

cairo_region_t *

cairo_region_create_rectangle (const cairo_rectangle_int_t *rectangle)

{

    cairo_region_t *region;

    region = _cairo_malloc (sizeof (cairo_region_t));

    if (unlikely (region == NULL))

	return (cairo_region_t *) &_cairo_region_nil;

    region->status = CAIRO_STATUS_SUCCESS;

    CAIRO_REFERENCE_COUNT_INIT (®ion->ref_count, 1);

    pixman_region32_init_rect (®ion->rgn,

			       rectangle->x, rectangle->y,

			       rectangle->width, rectangle->height);

    return region;

}

slim_hidden_def (cairo_region_create_rectangle);

/**

 * cairo_region_copy:

 * @original: a #cairo_region_t

 *

 * Allocates a new region object copying the area from @original.

 *

 * Return value: A newly allocated #cairo_region_t. Free with

 *   cairo_region_destroy(). This function always returns a

 *   valid pointer; if memory cannot be allocated, then a special

 *   error object is returned where all operations on the object do nothing.

 *   You can check for this with cairo_region_status().

 *

 * Since: 1.10

 **/

cairo_region_t *

cairo_region_copy (const cairo_region_t *original)

{

    cairo_region_t *copy;

    if (original != NULL && original->status)

	return (cairo_region_t *) &_cairo_region_nil;

    copy = cairo_region_create ();

    if (unlikely (copy->status))

	return copy;

    if (original != NULL &&

	! pixman_region32_copy (©->rgn, CONST_CAST &original->rgn))

    {

	cairo_region_destroy (copy);

	return (cairo_region_t *) &_cairo_region_nil;

    }

    return copy;

}

slim_hidden_def (cairo_region_copy);

/**

 * cairo_region_reference:

 * @region: a #cairo_region_t

 *

 * Increases the reference count on @region by one. This prevents

 * @region from being destroyed until a matching call to

 * cairo_region_destroy() is made.

 *

 * Return value: the referenced #cairo_region_t.

 *

 * Since: 1.10

 **/

cairo_region_t *

cairo_region_reference (cairo_region_t *region)

{

    if (region == NULL || CAIRO_REFERENCE_COUNT_IS_INVALID (®ion->ref_count))

	return NULL;

    assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE (®ion->ref_count));

    _cairo_reference_count_inc (®ion->ref_count);

    return region;

}

slim_hidden_def (cairo_region_reference);

/**

 * cairo_region_destroy:

 * @region: a #cairo_region_t

 *

 * Destroys a #cairo_region_t object created with

 * cairo_region_create(), cairo_region_copy(), or

 * or cairo_region_create_rectangle().

 *

 * Since: 1.10

 **/

void

cairo_region_destroy (cairo_region_t *region)

{

    if (region == NULL || CAIRO_REFERENCE_COUNT_IS_INVALID (®ion->ref_count))

	return;

    assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE (®ion->ref_count));

    if (! _cairo_reference_count_dec_and_test (®ion->ref_count))

	return;

    _cairo_region_fini (region);

    free (region);

}

slim_hidden_def (cairo_region_destroy);

/**

 * cairo_region_num_rectangles:

 * @region: a #cairo_region_t

 *

 * Returns the number of rectangles contained in @region.

 *

 * Return value: The number of rectangles contained in @region.

 *

 * Since: 1.10

 **/

int

cairo_region_num_rectangles (const cairo_region_t *region)

{

    if (region->status)

	return 0;

    return pixman_region32_n_rects (CONST_CAST ®ion->rgn);

}

slim_hidden_def (cairo_region_num_rectangles);

/**

 * cairo_region_get_rectangle:

 * @region: a #cairo_region_t

 * @nth: a number indicating which rectangle should be returned

 * @rectangle: return location for a #cairo_rectangle_int_t

 *

 * Stores the @nth rectangle from the region in @rectangle.

 *

 * Since: 1.10

 **/

void

cairo_region_get_rectangle (const cairo_region_t *region,

			    int nth,

			    cairo_rectangle_int_t *rectangle)

{

    pixman_box32_t *pbox;

    if (region->status) {

	rectangle->x = rectangle->y = 0;

	rectangle->width = rectangle->height = 0;

	return;

    }

    pbox = pixman_region32_rectangles (CONST_CAST ®ion->rgn, NULL) + nth;

    rectangle->x = pbox->x1;

    rectangle->y = pbox->y1;

    rectangle->width = pbox->x2 - pbox->x1;

    rectangle->height = pbox->y2 - pbox->y1;

}

slim_hidden_def (cairo_region_get_rectangle);

/**

 * cairo_region_get_extents:

 * @region: a #cairo_region_t

 * @extents: rectangle into which to store the extents

 *

 * Gets the bounding rectangle of @region as a #cairo_rectangle_int_t

 *

 * Since: 1.10

 **/

void

cairo_region_get_extents (const cairo_region_t *region,

			  cairo_rectangle_int_t *extents)

{

    pixman_box32_t *pextents;

    if (region->status) {

	extents->x = extents->y = 0;

	extents->width = extents->height = 0;

	return;

    }

    pextents = pixman_region32_extents (CONST_CAST ®ion->rgn);

    extents->x = pextents->x1;

    extents->y = pextents->y1;

    extents->width = pextents->x2 - pextents->x1;

    extents->height = pextents->y2 - pextents->y1;

}

slim_hidden_def (cairo_region_get_extents);

/**

 * cairo_region_status:

 * @region: a #cairo_region_t

 *

 * Checks whether an error has previous occurred for this

 * region object.

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_status (const cairo_region_t *region)

{

    return region->status;

}

slim_hidden_def (cairo_region_status);

/**

 * cairo_region_subtract:

 * @dst: a #cairo_region_t

 * @other: another #cairo_region_t

 *

 * Subtracts @other from @dst and places the result in @dst

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_subtract (cairo_region_t *dst, const cairo_region_t *other)

{

    if (dst->status)

	return dst->status;

    if (other->status)

	return _cairo_region_set_error (dst, other->status);

    if (! pixman_region32_subtract (&dst->rgn,

				    &dst->rgn,

				    CONST_CAST &other->rgn))

    {

	return _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    }

    return CAIRO_STATUS_SUCCESS;

}

slim_hidden_def (cairo_region_subtract);

/**

 * cairo_region_subtract_rectangle:

 * @dst: a #cairo_region_t

 * @rectangle: a #cairo_rectangle_int_t

 *

 * Subtracts @rectangle from @dst and places the result in @dst

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_subtract_rectangle (cairo_region_t *dst,

				 const cairo_rectangle_int_t *rectangle)

{

    cairo_status_t status = CAIRO_STATUS_SUCCESS;

    pixman_region32_t region;

    if (dst->status)

	return dst->status;

    pixman_region32_init_rect (®ion,

			       rectangle->x, rectangle->y,

			       rectangle->width, rectangle->height);

    if (! pixman_region32_subtract (&dst->rgn, &dst->rgn, ®ion))

	status = _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    pixman_region32_fini (®ion);

    return status;

}

slim_hidden_def (cairo_region_subtract_rectangle);

/**

 * cairo_region_intersect:

 * @dst: a #cairo_region_t

 * @other: another #cairo_region_t

 *

 * Computes the intersection of @dst with @other and places the result in @dst

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_intersect (cairo_region_t *dst, const cairo_region_t *other)

{

    if (dst->status)

	return dst->status;

    if (other->status)

	return _cairo_region_set_error (dst, other->status);

    if (! pixman_region32_intersect (&dst->rgn, &dst->rgn, CONST_CAST &other->rgn))

	return _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    return CAIRO_STATUS_SUCCESS;

}

slim_hidden_def (cairo_region_intersect);

/**

 * cairo_region_intersect_rectangle:

 * @dst: a #cairo_region_t

 * @rectangle: a #cairo_rectangle_int_t

 *

 * Computes the intersection of @dst with @rectangle and places the

 * result in @dst

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_intersect_rectangle (cairo_region_t *dst,

				  const cairo_rectangle_int_t *rectangle)

{

    cairo_status_t status = CAIRO_STATUS_SUCCESS;

    pixman_region32_t region;

    if (dst->status)

	return dst->status;

    pixman_region32_init_rect (®ion,

			       rectangle->x, rectangle->y,

			       rectangle->width, rectangle->height);

    if (! pixman_region32_intersect (&dst->rgn, &dst->rgn, ®ion))

	status = _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    pixman_region32_fini (®ion);

    return status;

}

slim_hidden_def (cairo_region_intersect_rectangle);

/**

 * cairo_region_union:

 * @dst: a #cairo_region_t

 * @other: another #cairo_region_t

 *

 * Computes the union of @dst with @other and places the result in @dst

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_union (cairo_region_t *dst,

		    const cairo_region_t *other)

{

    if (dst->status)

	return dst->status;

    if (other->status)

	return _cairo_region_set_error (dst, other->status);

    if (! pixman_region32_union (&dst->rgn, &dst->rgn, CONST_CAST &other->rgn))

	return _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    return CAIRO_STATUS_SUCCESS;

}

slim_hidden_def (cairo_region_union);

/**

 * cairo_region_union_rectangle:

 * @dst: a #cairo_region_t

 * @rectangle: a #cairo_rectangle_int_t

 *

 * Computes the union of @dst with @rectangle and places the result in @dst.

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_union_rectangle (cairo_region_t *dst,

			      const cairo_rectangle_int_t *rectangle)

{

    cairo_status_t status = CAIRO_STATUS_SUCCESS;

    pixman_region32_t region;

    if (dst->status)

	return dst->status;

    pixman_region32_init_rect (®ion,

			       rectangle->x, rectangle->y,

			       rectangle->width, rectangle->height);

    if (! pixman_region32_union (&dst->rgn, &dst->rgn, ®ion))

	status = _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    pixman_region32_fini (®ion);

    return status;

}

slim_hidden_def (cairo_region_union_rectangle);

/**

 * cairo_region_xor:

 * @dst: a #cairo_region_t

 * @other: another #cairo_region_t

 *

 * Computes the exclusive difference of @dst with @other and places the

 * result in @dst. That is, @dst will be set to contain all areas that

 * are either in @dst or in @other, but not in both.

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_xor (cairo_region_t *dst, const cairo_region_t *other)

{

    cairo_status_t status = CAIRO_STATUS_SUCCESS;

    pixman_region32_t tmp;

    if (dst->status)

	return dst->status;

    if (other->status)

	return _cairo_region_set_error (dst, other->status);

    pixman_region32_init (&tmp);

    /* XXX: get an xor function into pixman */

    if (! pixman_region32_subtract (&tmp, CONST_CAST &other->rgn, &dst->rgn) ||

        ! pixman_region32_subtract (&dst->rgn, &dst->rgn, CONST_CAST &other->rgn) ||

        ! pixman_region32_union (&dst->rgn, &dst->rgn, &tmp))

	status = _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    pixman_region32_fini (&tmp);

    return status;

}

slim_hidden_def (cairo_region_xor);

/**

 * cairo_region_xor_rectangle:

 * @dst: a #cairo_region_t

 * @rectangle: a #cairo_rectangle_int_t

 *

 * Computes the exclusive difference of @dst with @rectangle and places the

 * result in @dst. That is, @dst will be set to contain all areas that are

 * either in @dst or in @rectangle, but not in both.

 *

 * Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY

 *

 * Since: 1.10

 **/

cairo_status_t

cairo_region_xor_rectangle (cairo_region_t *dst,

			    const cairo_rectangle_int_t *rectangle)

{

    cairo_status_t status = CAIRO_STATUS_SUCCESS;

    pixman_region32_t region, tmp;

    if (dst->status)

	return dst->status;

    pixman_region32_init_rect (®ion,

			       rectangle->x, rectangle->y,

			       rectangle->width, rectangle->height);

    pixman_region32_init (&tmp);

    /* XXX: get an xor function into pixman */

    if (! pixman_region32_subtract (&tmp, ®ion, &dst->rgn) ||

        ! pixman_region32_subtract (&dst->rgn, &dst->rgn, ®ion) ||

        ! pixman_region32_union (&dst->rgn, &dst->rgn, &tmp))

	status = _cairo_region_set_error (dst, CAIRO_STATUS_NO_MEMORY);

    pixman_region32_fini (&tmp);

    pixman_region32_fini (®ion);

    return status;

}

slim_hidden_def (cairo_region_xor_rectangle);

/**

 * cairo_region_is_empty:

 * @region: a #cairo_region_t

 *

 * Checks whether @region is empty.

 *

 * Return value: %TRUE if @region is empty, %FALSE if it isn't.

 *

 * Since: 1.10

 **/

cairo_bool_t

cairo_region_is_empty (const cairo_region_t *region)

{

    if (region->status)

	return TRUE;

    return ! pixman_region32_not_empty (CONST_CAST ®ion->rgn);

}

slim_hidden_def (cairo_region_is_empty);

/**

 * cairo_region_translate:

 * @region: a #cairo_region_t

 * @dx: Amount to translate in the x direction

 * @dy: Amount to translate in the y direction

 *

 * Translates @region by (@dx, @dy).

 *

 * Since: 1.10

 **/

void

cairo_region_translate (cairo_region_t *region,

			int dx, int dy)

{

    if (region->status)

	return;

    pixman_region32_translate (®ion->rgn, dx, dy);

}

slim_hidden_def (cairo_region_translate);

/**

 * cairo_region_overlap_t:

 * @CAIRO_REGION_OVERLAP_IN: The contents are entirely inside the region. (Since 1.10)

 * @CAIRO_REGION_OVERLAP_OUT: The contents are entirely outside the region. (Since 1.10)

 * @CAIRO_REGION_OVERLAP_PART: The contents are partially inside and

 *     partially outside the region. (Since 1.10)

 *

 * Used as the return value for cairo_region_contains_rectangle().

 *

 * Since: 1.10

 **/

/**

 * cairo_region_contains_rectangle:

 * @region: a #cairo_region_t

 * @rectangle: a #cairo_rectangle_int_t

 *

 * Checks whether @rectangle is inside, outside or partially contained

 * in @region

 *

 * Return value:

 *   %CAIRO_REGION_OVERLAP_IN if @rectangle is entirely inside @region,

 *   %CAIRO_REGION_OVERLAP_OUT if @rectangle is entirely outside @region, or

 *   %CAIRO_REGION_OVERLAP_PART if @rectangle is partially inside and partially outside @region.

 *

 * Since: 1.10

 **/

cairo_region_overlap_t

cairo_region_contains_rectangle (const cairo_region_t *region,

				 const cairo_rectangle_int_t *rectangle)

{

    pixman_box32_t pbox;

    pixman_region_overlap_t poverlap;

    if (region->status)

	return CAIRO_REGION_OVERLAP_OUT;

    pbox.x1 = rectangle->x;

    pbox.y1 = rectangle->y;

    pbox.x2 = rectangle->x + rectangle->width;

    pbox.y2 = rectangle->y + rectangle->height;

    poverlap = pixman_region32_contains_rectangle (CONST_CAST ®ion->rgn,

						   &pbox);

    switch (poverlap) {

    default:

    case PIXMAN_REGION_OUT:  return CAIRO_REGION_OVERLAP_OUT;

    case PIXMAN_REGION_IN:   return CAIRO_REGION_OVERLAP_IN;

    case PIXMAN_REGION_PART: return CAIRO_REGION_OVERLAP_PART;

    }

}

slim_hidden_def (cairo_region_contains_rectangle);

/**

 * cairo_region_contains_point:

 * @region: a #cairo_region_t

 * @x: the x coordinate of a point

 * @y: the y coordinate of a point

 *

 * Checks whether (@x, @y) is contained in @region.

 *

 * Return value: %TRUE if (@x, @y) is contained in @region, %FALSE if it is not.

 *

 * Since: 1.10

 **/

cairo_bool_t

cairo_region_contains_point (const cairo_region_t *region,

			     int x, int y)

{

    pixman_box32_t box;

    if (region->status)

	return FALSE;

    return pixman_region32_contains_point (CONST_CAST ®ion->rgn, x, y, &box);

}

slim_hidden_def (cairo_region_contains_point);

/**

 * cairo_region_equal:

 * @a: a #cairo_region_t or %NULL

 * @b: a #cairo_region_t or %NULL

 *

 * Compares whether region_a is equivalent to region_b. %NULL as an argument

 * is equal to itself, but not to any non-%NULL region.

 *

 * Return value: %TRUE if both regions contained the same coverage,

 * %FALSE if it is not or any region is in an error status.

 *

 * Since: 1.10

 **/

cairo_bool_t

cairo_region_equal (const cairo_region_t *a,

		    const cairo_region_t *b)

{

    /* error objects are never equal */

    if ((a != NULL && a->status) || (b != NULL && b->status))

	return FALSE;

    if (a == b)

	return TRUE;

    if (a == NULL || b == NULL)

	return FALSE;

    return pixman_region32_equal (CONST_CAST &a->rgn, CONST_CAST &b->rgn);

}

slim_hidden_def (cairo_region_equal);