1 /* cairo - a vector graphics library with display and print output
2 *
3 * Copyright © 2009 Chris Wilson
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it either under the terms of the GNU Lesser General Public
7 * License version 2.1 as published by the Free Software Foundation
8 * (the "LGPL") or, at your option, under the terms of the Mozilla
9 * Public License Version 1.1 (the "MPL"). If you do not alter this
10 * notice, a recipient may use your version of this file under either
11 * the MPL or the LGPL.
12 *
13 * You should have received a copy of the LGPL along with this library
14 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
16 * You should have received a copy of the MPL along with this library
17 * in the file COPYING-MPL-1.1
18 *
19 * The contents of this file are subject to the Mozilla Public License
20 * Version 1.1 (the "License"); you may not use this file except in
21 * compliance with the License. You may obtain a copy of the License at
22 * http://www.mozilla.org/MPL/
23 *
24 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
25 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
26 * the specific language governing rights and limitations.
27 *
28 * The Original Code is the cairo graphics library.
29 *
30 * The Initial Developer of the Original Code is Red Hat, Inc.
31 *
32 * Contributor(s):
33 * Chris Wilson <chris@chris-wilson.co.uk>
34 */
35
36 #include "cairoint.h"
37
38 #include "cairo-surface-clipper-private.h"
39
40 /* A collection of routines to facilitate vector surface clipping */
41
42 static cairo_status_t
_cairo_surface_clipper_intersect_clip_path_recursive(cairo_surface_clipper_t * clipper,cairo_clip_path_t * clip_path)43 _cairo_surface_clipper_intersect_clip_path_recursive (cairo_surface_clipper_t *clipper,
44 cairo_clip_path_t *clip_path)
45 {
46 cairo_status_t status;
47
48 if (clip_path->prev != NULL) {
49 status =
50 _cairo_surface_clipper_intersect_clip_path_recursive (clipper,
51 clip_path->prev);
52 if (unlikely (status))
53 return status;
54 }
55
56 return clipper->intersect_clip_path (clipper,
57 &clip_path->path,
58 clip_path->fill_rule,
59 clip_path->tolerance,
60 clip_path->antialias);
61 }
62
63 cairo_status_t
_cairo_surface_clipper_set_clip(cairo_surface_clipper_t * clipper,cairo_clip_t * clip)64 _cairo_surface_clipper_set_clip (cairo_surface_clipper_t *clipper,
65 cairo_clip_t *clip)
66 {
67 cairo_status_t status;
68 cairo_bool_t clear;
69
70 /* XXX as we cache a reference to the path, and compare every time,
71 * we may in future need to install a notification if the clip->path
72 * is every modified (e.g. cairo_clip_translate).
73 */
74
75 if (clip == NULL && clipper->clip.path == NULL)
76 return CAIRO_STATUS_SUCCESS;
77
78 if (clip != NULL && clipper->clip.path != NULL &&
79 _cairo_clip_equal (clip, &clipper->clip))
80 {
81 return CAIRO_STATUS_SUCCESS;
82 }
83
84 /* all clipped out state should never propagate this far */
85 assert (clip == NULL || clip->path != NULL);
86
87 /* Check whether this clip is a continuation of the previous.
88 * If not, we have to remove the current clip and rebuild.
89 */
90 clear = clip == NULL || clip->path->prev != clipper->clip.path;
91
92 _cairo_clip_reset (&clipper->clip);
93 _cairo_clip_init_copy (&clipper->clip, clip);
94
95 if (clear) {
96 clipper->is_clipped = FALSE;
97 status = clipper->intersect_clip_path (clipper, NULL, 0, 0, 0);
98 if (unlikely (status))
99 return status;
100
101 if (clip != NULL && clip->path != NULL) {
102 status =
103 _cairo_surface_clipper_intersect_clip_path_recursive (clipper,
104 clip->path);
105 clipper->is_clipped = TRUE;
106 }
107 } else {
108 cairo_clip_path_t *path = clip->path;
109
110 clipper->is_clipped = TRUE;
111 status = clipper->intersect_clip_path (clipper,
112 &path->path,
113 path->fill_rule,
114 path->tolerance,
115 path->antialias);
116 }
117
118 return status;
119 }
120
121 void
_cairo_surface_clipper_init(cairo_surface_clipper_t * clipper,cairo_surface_clipper_intersect_clip_path_func_t func)122 _cairo_surface_clipper_init (cairo_surface_clipper_t *clipper,
123 cairo_surface_clipper_intersect_clip_path_func_t func)
124 {
125 _cairo_clip_init (&clipper->clip);
126 clipper->is_clipped = FALSE;
127 clipper->intersect_clip_path = func;
128 }
129
130 void
_cairo_surface_clipper_reset(cairo_surface_clipper_t * clipper)131 _cairo_surface_clipper_reset (cairo_surface_clipper_t *clipper)
132 {
133 _cairo_clip_reset (&clipper->clip);
134 clipper->is_clipped = FALSE;
135 }
136