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/* cairo - a vector graphics library with display and print output
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 *
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 * Copyright © 2009 Chris Wilson
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it either under the terms of the GNU Lesser General Public
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 * License version 2.1 as published by the Free Software Foundation
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 * (the "LGPL") or, at your option, under the terms of the Mozilla
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 * Public License Version 1.1 (the "MPL"). If you do not alter this
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 * notice, a recipient may use your version of this file under either
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 * the MPL or the LGPL.
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 *
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 * You should have received a copy of the LGPL along with this library
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 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
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 * You should have received a copy of the MPL along with this library
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 * in the file COPYING-MPL-1.1
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 *
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 * The contents of this file are subject to the Mozilla Public License
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 * Version 1.1 (the "License"); you may not use this file except in
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 * compliance with the License. You may obtain a copy of the License at
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 * http://www.mozilla.org/MPL/
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 *
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 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
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 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
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 * the specific language governing rights and limitations.
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 *
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 * The Original Code is the cairo graphics library.
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 *
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 * The Initial Developer of the Original Code is Red Hat, Inc.
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 *
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 * Contributor(s):
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 *      Chris Wilson <chris@chris-wilson.co.uk>
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 */
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#include "cairoint.h"
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#include "cairo-clip-inline.h"
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#include "cairo-surface-clipper-private.h"
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/* A collection of routines to facilitate vector surface clipping */
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/* XXX Eliminate repeated paths and nested clips */
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static cairo_status_t
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_cairo_path_fixed_add_box (cairo_path_fixed_t *path,
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			   const cairo_box_t *box)
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{
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    cairo_status_t status;
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    status = _cairo_path_fixed_move_to (path, box->p1.x, box->p1.y);
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    if (unlikely (status))
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	return status;
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    status = _cairo_path_fixed_line_to (path, box->p2.x, box->p1.y);
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    if (unlikely (status))
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	return status;
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    status = _cairo_path_fixed_line_to (path, box->p2.x, box->p2.y);
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    if (unlikely (status))
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	return status;
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    status = _cairo_path_fixed_line_to (path, box->p1.x, box->p2.y);
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    if (unlikely (status))
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	return status;
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    return _cairo_path_fixed_close_path (path);
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}
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static cairo_status_t
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_cairo_surface_clipper_intersect_clip_boxes (cairo_surface_clipper_t *clipper,
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					     const cairo_clip_t *clip)
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{
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    cairo_path_fixed_t path;
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    cairo_status_t status;
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    int i;
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    if (clip->num_boxes == 0)
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	return CAIRO_STATUS_SUCCESS;
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    /* Reconstruct the path for the clip boxes.
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     * XXX maybe a new clipper callback?
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     */
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    _cairo_path_fixed_init (&path);
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    for (i = 0; i < clip->num_boxes; i++) {
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	status = _cairo_path_fixed_add_box (&path, &clip->boxes[i]);
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	if (unlikely (status)) {
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	    _cairo_path_fixed_fini (&path);
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	    return status;
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	}
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    }
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    status = clipper->intersect_clip_path (clipper, &path,
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					   CAIRO_FILL_RULE_WINDING,
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					   0.,
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					   CAIRO_ANTIALIAS_DEFAULT);
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    _cairo_path_fixed_fini (&path);
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    return status;
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}
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static cairo_status_t
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_cairo_surface_clipper_intersect_clip_path_recursive (cairo_surface_clipper_t *clipper,
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						      cairo_clip_path_t *clip_path,
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						      cairo_clip_path_t *end)
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{
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    cairo_status_t status;
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    if (clip_path->prev != end) {
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	status =
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	    _cairo_surface_clipper_intersect_clip_path_recursive (clipper,
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								  clip_path->prev,
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								  end);
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	if (unlikely (status))
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	    return status;
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    }
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    return clipper->intersect_clip_path (clipper,
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					 &clip_path->path,
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					 clip_path->fill_rule,
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					 clip_path->tolerance,
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					 clip_path->antialias);
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}
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cairo_status_t
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_cairo_surface_clipper_set_clip (cairo_surface_clipper_t *clipper,
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				 const cairo_clip_t *clip)
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{
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    cairo_status_t status;
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    cairo_bool_t incremental = FALSE;
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    if (_cairo_clip_equal (clip, clipper->clip))
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	return CAIRO_STATUS_SUCCESS;
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    /* all clipped out state should never propagate this far */
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    assert (!_cairo_clip_is_all_clipped (clip));
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    /* XXX Is this an incremental clip? */
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    if (clipper->clip && clip &&
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	clip->num_boxes == clipper->clip->num_boxes &&
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	memcmp (clip->boxes, clipper->clip->boxes,
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		sizeof (cairo_box_t) * clip->num_boxes) == 0)
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    {
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	cairo_clip_path_t *clip_path = clip->path;
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	while (clip_path != NULL && clip_path != clipper->clip->path)
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	    clip_path = clip_path->prev;
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	if (clip_path) {
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	    incremental = TRUE;
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	    status = _cairo_surface_clipper_intersect_clip_path_recursive (clipper,
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									   clip->path,
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									   clipper->clip->path);
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	}
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    }
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    _cairo_clip_destroy (clipper->clip);
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    clipper->clip = _cairo_clip_copy (clip);
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    if (incremental)
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	return status;
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    status = clipper->intersect_clip_path (clipper, NULL, 0, 0, 0);
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    if (unlikely (status))
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	return status;
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    if (clip == NULL)
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	return CAIRO_STATUS_SUCCESS;
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    status = _cairo_surface_clipper_intersect_clip_boxes (clipper, clip);
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    if (unlikely (status))
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	return status;
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    if (clip->path != NULL) {
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	    status = _cairo_surface_clipper_intersect_clip_path_recursive (clipper,
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									   clip->path,
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									   NULL);
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    }
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    return status;
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}
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void
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_cairo_surface_clipper_init (cairo_surface_clipper_t *clipper,
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			     cairo_surface_clipper_intersect_clip_path_func_t func)
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{
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    clipper->clip = NULL;
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    clipper->intersect_clip_path = func;
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}
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void
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_cairo_surface_clipper_reset (cairo_surface_clipper_t *clipper)
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{
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    _cairo_clip_destroy (clipper->clip);
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    clipper->clip = NULL;
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}