summaryrefslogtreecommitdiff
path: root/src/cairo-surface-clipper.c
blob: d536f0cbe50b8065709f2b954691bd6e76b64768 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
/* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 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-surface-clipper-private.h"

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

static cairo_status_t
_cairo_surface_clipper_intersect_clip_path_recursive (cairo_surface_clipper_t *clipper,
						      cairo_clip_path_t *clip_path)
{
    cairo_status_t status;

    if (clip_path->prev != NULL) {
	status =
	    _cairo_surface_clipper_intersect_clip_path_recursive (clipper,
								  clip_path->prev);
	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,
				 cairo_clip_t *clip)
{
    cairo_status_t status;
    cairo_bool_t clear;

    /* XXX as we cache a reference to the path, and compare every time,
     * we may in future need to install a notification if the clip->path
     * is every modified (e.g. cairo_clip_translate).
     */

    if (clip == NULL && clipper->clip.path == NULL)
	return CAIRO_STATUS_SUCCESS;

    if (clip != NULL && clip->path == clipper->clip.path)
	return CAIRO_STATUS_SUCCESS;

    if (clip != NULL && clipper->clip.path != NULL &&
	_cairo_path_fixed_equal (&clip->path->path, &clipper->clip.path->path))
    {
	return CAIRO_STATUS_SUCCESS;
    }

    /* all clipped out state should never propagate this far */
    assert (clip == NULL || clip->path != NULL);

    /* Check whether this clip is a continuation of the previous.
     * If not, we have to remove the current clip and rebuild.
     */
    clear = clip == NULL || clip->path->prev != clipper->clip.path;

    _cairo_clip_reset (&clipper->clip);
    _cairo_clip_init_copy (&clipper->clip, clip);

    if (clear) {
	clipper->is_clipped = FALSE;
	status = clipper->intersect_clip_path (clipper, NULL, 0, 0, 0);
	if (unlikely (status))
	    return status;

	if (clip != NULL && clip->path != NULL) {
	    status =
		_cairo_surface_clipper_intersect_clip_path_recursive (clipper,
								      clip->path);
	    clipper->is_clipped = TRUE;
	}
    } else {
	cairo_clip_path_t *path = clip->path;

	clipper->is_clipped = TRUE;
	status = clipper->intersect_clip_path (clipper,
					       &path->path,
					       path->fill_rule,
					       path->tolerance,
					       path->antialias);
    }

    return status;
}

void
_cairo_surface_clipper_init (cairo_surface_clipper_t *clipper,
			     cairo_surface_clipper_intersect_clip_path_func_t func)
{
    _cairo_clip_init (&clipper->clip);
    clipper->is_clipped = FALSE;
    clipper->intersect_clip_path = func;
}

void
_cairo_surface_clipper_reset (cairo_surface_clipper_t *clipper)
{
    _cairo_clip_reset (&clipper->clip);
    clipper->is_clipped = FALSE;
}