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

 *

 * Copyright © 2009 Chris Wilson

 *

 * 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 

 */

#include "cairoint.h"

#include "cairo-clip-inline.h"

#include "cairo-surface-clipper-private.h"

/* A collection of routines to facilitate vector surface clipping */

/* XXX Eliminate repeated paths and nested clips */

static cairo_status_t

_cairo_path_fixed_add_box (cairo_path_fixed_t *path,

			   const cairo_box_t *box)

{

    cairo_status_t status;

    status = _cairo_path_fixed_move_to (path, box->p1.x, box->p1.y);

    if (unlikely (status))

	return status;

    status = _cairo_path_fixed_line_to (path, box->p2.x, box->p1.y);

    if (unlikely (status))

	return status;

    status = _cairo_path_fixed_line_to (path, box->p2.x, box->p2.y);

    if (unlikely (status))

	return status;

    status = _cairo_path_fixed_line_to (path, box->p1.x, box->p2.y);

    if (unlikely (status))

	return status;

    return _cairo_path_fixed_close_path (path);

}

static cairo_status_t

_cairo_surface_clipper_intersect_clip_boxes (cairo_surface_clipper_t *clipper,

					     const cairo_clip_t *clip)

{

    cairo_path_fixed_t path;

    cairo_status_t status;

    int i;

    if (clip->num_boxes == 0)

	return CAIRO_STATUS_SUCCESS;

    /* Reconstruct the path for the clip boxes.

     * XXX maybe a new clipper callback?

     */

    _cairo_path_fixed_init (&path);

    for (i = 0; i < clip->num_boxes; i++) {

	status = _cairo_path_fixed_add_box (&path, &clip->boxes[i]);

	if (unlikely (status)) {

	    _cairo_path_fixed_fini (&path);

	    return status;

	}

    }

    status = clipper->intersect_clip_path (clipper, &path,

					   CAIRO_FILL_RULE_WINDING,

					   0.,

					   CAIRO_ANTIALIAS_DEFAULT);

    _cairo_path_fixed_fini (&path);

    return status;

}

static cairo_status_t

_cairo_surface_clipper_intersect_clip_path_recursive (cairo_surface_clipper_t *clipper,

						      cairo_clip_path_t *clip_path,

						      cairo_clip_path_t *end)

{

    cairo_status_t status;

    if (clip_path->prev != end) {

	status =

	    _cairo_surface_clipper_intersect_clip_path_recursive (clipper,

								  clip_path->prev,

								  end);

	if (unlikely (status))

	    return status;

    }

    return clipper->intersect_clip_path (clipper,

					 &clip_path->path,

					 clip_path->fill_rule,

					 clip_path->tolerance,

					 clip_path->antialias);

}

cairo_status_t

_cairo_surface_clipper_set_clip (cairo_surface_clipper_t *clipper,

				 const cairo_clip_t *clip)

{

    cairo_status_t status;

    cairo_bool_t incremental = FALSE;

    if (_cairo_clip_equal (clip, clipper->clip))

	return CAIRO_STATUS_SUCCESS;

    /* all clipped out state should never propagate this far */

    assert (!_cairo_clip_is_all_clipped (clip));

    /* XXX Is this an incremental clip? */

    if (clipper->clip && clip &&

	clip->num_boxes == clipper->clip->num_boxes &&

	memcmp (clip->boxes, clipper->clip->boxes,

		sizeof (cairo_box_t) * clip->num_boxes) == 0)

    {

	cairo_clip_path_t *clip_path = clip->path;

	while (clip_path != NULL && clip_path != clipper->clip->path)

	    clip_path = clip_path->prev;

	if (clip_path) {

	    incremental = TRUE;

	    status = _cairo_surface_clipper_intersect_clip_path_recursive (clipper,

									   clip->path,

									   clipper->clip->path);

	}

    }

    _cairo_clip_destroy (clipper->clip);

    clipper->clip = _cairo_clip_copy (clip);

    if (incremental)

	return status;

    status = clipper->intersect_clip_path (clipper, NULL, 0, 0, 0);

    if (unlikely (status))

	return status;

    if (clip == NULL)

	return CAIRO_STATUS_SUCCESS;

    status = _cairo_surface_clipper_intersect_clip_boxes (clipper, clip);

    if (unlikely (status))

	return status;

    if (clip->path != NULL) {

	    status = _cairo_surface_clipper_intersect_clip_path_recursive (clipper,

									   clip->path,

									   NULL);

    }

    return status;

}

void

_cairo_surface_clipper_init (cairo_surface_clipper_t *clipper,

			     cairo_surface_clipper_intersect_clip_path_func_t func)

{

    clipper->clip = NULL;

    clipper->intersect_clip_path = func;

}

void

_cairo_surface_clipper_reset (cairo_surface_clipper_t *clipper)

{

    _cairo_clip_destroy (clipper->clip);

    clipper->clip = NULL;

}