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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
|
/* cairo - a vector graphics library with display and print output
*
* Copyright © 2002 University of Southern California
*
* 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 University of Southern
* California.
*
* Contributor(s):
* Carl D. Worth <cworth@cworth.org>
*/
#include "cairoint.h"
/* private functions */
static cairo_status_t
_cairo_polygon_grow (cairo_polygon_t *polygon);
void
_cairo_polygon_init (cairo_polygon_t *polygon)
{
polygon->status = CAIRO_STATUS_SUCCESS;
polygon->num_edges = 0;
polygon->edges_size = 0;
polygon->edges = NULL;
polygon->has_current_point = FALSE;
}
void
_cairo_polygon_fini (cairo_polygon_t *polygon)
{
if (polygon->edges && polygon->edges != polygon->edges_embedded)
free (polygon->edges);
polygon->edges = NULL;
polygon->edges_size = 0;
polygon->num_edges = 0;
polygon->has_current_point = FALSE;
}
cairo_status_t
_cairo_polygon_status (cairo_polygon_t *polygon)
{
return polygon->status;
}
/* make room for at least one more edge */
static cairo_status_t
_cairo_polygon_grow (cairo_polygon_t *polygon)
{
cairo_edge_t *new_edges;
int old_size = polygon->edges_size;
int embedded_size = ARRAY_LENGTH (polygon->edges_embedded);
int new_size = 2 * MAX (old_size, 16);
/* we have a local buffer at polygon->edges_embedded. try to fulfill the request
* from there. */
if (old_size < embedded_size) {
polygon->edges = polygon->edges_embedded;
polygon->edges_size = embedded_size;
return CAIRO_STATUS_SUCCESS;
}
assert (polygon->num_edges <= polygon->edges_size);
if (polygon->edges == polygon->edges_embedded) {
new_edges = _cairo_malloc_ab (new_size, sizeof (cairo_edge_t));
if (new_edges)
memcpy (new_edges, polygon->edges, old_size * sizeof (cairo_edge_t));
} else {
new_edges = _cairo_realloc_ab (polygon->edges,
new_size, sizeof (cairo_edge_t));
}
if (new_edges == NULL) {
_cairo_error (CAIRO_STATUS_NO_MEMORY);
return CAIRO_STATUS_NO_MEMORY;
}
polygon->edges = new_edges;
polygon->edges_size = new_size;
return CAIRO_STATUS_SUCCESS;
}
void
_cairo_polygon_add_edge (cairo_polygon_t *polygon, cairo_point_t *p1, cairo_point_t *p2)
{
cairo_edge_t *edge;
if (polygon->status)
return;
/* drop horizontal edges */
if (p1->y == p2->y)
goto DONE;
if (polygon->num_edges >= polygon->edges_size) {
polygon->status = _cairo_polygon_grow (polygon);
if (polygon->status)
return;
}
edge = &polygon->edges[polygon->num_edges];
if (p1->y < p2->y) {
edge->edge.p1 = *p1;
edge->edge.p2 = *p2;
edge->clockWise = 1;
} else {
edge->edge.p1 = *p2;
edge->edge.p2 = *p1;
edge->clockWise = 0;
}
polygon->num_edges++;
DONE:
_cairo_polygon_move_to (polygon, p2);
}
void
_cairo_polygon_move_to (cairo_polygon_t *polygon, cairo_point_t *point)
{
if (polygon->status)
return;
if (! polygon->has_current_point)
polygon->first_point = *point;
polygon->current_point = *point;
polygon->has_current_point = TRUE;
}
void
_cairo_polygon_line_to (cairo_polygon_t *polygon, cairo_point_t *point)
{
if (polygon->status)
return;
if (polygon->has_current_point) {
_cairo_polygon_add_edge (polygon, &polygon->current_point, point);
} else {
_cairo_polygon_move_to (polygon, point);
}
}
void
_cairo_polygon_close (cairo_polygon_t *polygon)
{
if (polygon->status)
return;
if (polygon->has_current_point) {
_cairo_polygon_add_edge (polygon,
&polygon->current_point,
&polygon->first_point);
polygon->has_current_point = FALSE;
}
}
|