1
/* cairo - a vector graphics library with display and print output
2
 *
3
 * Copyright © 2005 Red Hat, Inc.
4
 * Copyright © 2006 Red Hat, Inc.
5
 *
6
 * This library is free software; you can redistribute it and/or
7
 * modify it either under the terms of the GNU Lesser General Public
8
 * License version 2.1 as published by the Free Software Foundation
9
 * (the "LGPL") or, at your option, under the terms of the Mozilla
10
 * 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
12
 * the MPL or the LGPL.
13
 *
14
 * You should have received a copy of the LGPL along with this library
15
 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
16
 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
17
 * You should have received a copy of the MPL along with this library
18
 * in the file COPYING-MPL-1.1
19
 *
20
 * The contents of this file are subject to the Mozilla Public License
21
 * Version 1.1 (the "License"); you may not use this file except in
22
 * compliance with the License. You may obtain a copy of the License at
23
 * http://www.mozilla.org/MPL/
24
 *
25
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
26
 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
27
 * the specific language governing rights and limitations.
28
 *
29
 * The Original Code is the cairo graphics library.
30
 *
31
 * The Initial Developer of the Original Code is Red Hat, Inc.
32
 *
33
 * Contributor(s):
34
 *	Carl D. Worth <cworth@redhat.com>
35
 */
36

            
37
#include "cairoint.h"
38

            
39
#include "cairo-private.h"
40
#include "cairo-backend-private.h"
41
#include "cairo-error-private.h"
42
#include "cairo-path-private.h"
43
#include "cairo-path-fixed-private.h"
44

            
45
/**
46
 * SECTION:cairo-paths
47
 * @Title: Paths
48
 * @Short_Description: Creating paths and manipulating path data
49
 *
50
 * Paths are the most basic drawing tools and are primarily used to implicitly
51
 * generate simple masks.
52
 **/
53

            
54
static const cairo_path_t _cairo_path_nil = { CAIRO_STATUS_NO_MEMORY, NULL, 0 };
55

            
56
/* Closure for path interpretation. */
57
typedef struct cairo_path_count {
58
    int count;
59
} cpc_t;
60

            
61
static cairo_status_t
62
768
_cpc_move_to (void *closure,
63
	      const cairo_point_t *point)
64
{
65
768
    cpc_t *cpc = closure;
66

            
67
768
    cpc->count += 2;
68

            
69
768
    return CAIRO_STATUS_SUCCESS;
70
}
71

            
72
static cairo_status_t
73
1200
_cpc_line_to (void *closure,
74
	      const cairo_point_t *point)
75
{
76
1200
    cpc_t *cpc = closure;
77

            
78
1200
    cpc->count += 2;
79

            
80
1200
    return CAIRO_STATUS_SUCCESS;
81
}
82

            
83
static cairo_status_t
84
766
_cpc_curve_to (void		*closure,
85
	       const cairo_point_t	*p1,
86
	       const cairo_point_t	*p2,
87
	       const cairo_point_t	*p3)
88
{
89
766
    cpc_t *cpc = closure;
90

            
91
766
    cpc->count += 4;
92

            
93
766
    return CAIRO_STATUS_SUCCESS;
94
}
95

            
96
static cairo_status_t
97
304
_cpc_close_path (void *closure)
98
{
99
304
    cpc_t *cpc = closure;
100

            
101
304
    cpc->count += 1;
102

            
103
304
    return CAIRO_STATUS_SUCCESS;
104
}
105

            
106
static int
107
456
_cairo_path_count (cairo_path_t		*path,
108
		   cairo_path_fixed_t	*path_fixed,
109
		   double		 tolerance,
110
		   cairo_bool_t		 flatten)
111
{
112
    cairo_status_t status;
113
    cpc_t cpc;
114

            
115
456
    cpc.count = 0;
116

            
117
456
    if (flatten) {
118
12
	status = _cairo_path_fixed_interpret_flat (path_fixed,
119
						   _cpc_move_to,
120
						   _cpc_line_to,
121
						   _cpc_close_path,
122
						   &cpc,
123
						   tolerance);
124
    } else {
125
444
	status = _cairo_path_fixed_interpret (path_fixed,
126
					      _cpc_move_to,
127
					      _cpc_line_to,
128
					      _cpc_curve_to,
129
					      _cpc_close_path,
130
					      &cpc);
131
    }
132

            
133
456
    if (unlikely (status))
134
	return -1;
135

            
136
456
    return cpc.count;
137
}
138

            
139
/* Closure for path interpretation. */
140
typedef struct cairo_path_populate {
141
    cairo_path_data_t *data;
142
    cairo_t *cr;
143
} cpp_t;
144

            
145
static cairo_status_t
146
768
_cpp_move_to (void *closure,
147
	      const cairo_point_t *point)
148
{
149
768
    cpp_t *cpp = closure;
150
768
    cairo_path_data_t *data = cpp->data;
151
    double x, y;
152

            
153
768
    x = _cairo_fixed_to_double (point->x);
154
768
    y = _cairo_fixed_to_double (point->y);
155

            
156
768
    _cairo_backend_to_user (cpp->cr, &x, &y);
157

            
158
768
    data->header.type = CAIRO_PATH_MOVE_TO;
159
768
    data->header.length = 2;
160

            
161
    /* We index from 1 to leave room for data->header */
162
768
    data[1].point.x = x;
163
768
    data[1].point.y = y;
164

            
165
768
    cpp->data += data->header.length;
166

            
167
768
    return CAIRO_STATUS_SUCCESS;
168
}
169

            
170
static cairo_status_t
171
1200
_cpp_line_to (void *closure,
172
	      const cairo_point_t *point)
173
{
174
1200
    cpp_t *cpp = closure;
175
1200
    cairo_path_data_t *data = cpp->data;
176
    double x, y;
177

            
178
1200
    x = _cairo_fixed_to_double (point->x);
179
1200
    y = _cairo_fixed_to_double (point->y);
180

            
181
1200
    _cairo_backend_to_user (cpp->cr, &x, &y);
182

            
183
1200
    data->header.type = CAIRO_PATH_LINE_TO;
184
1200
    data->header.length = 2;
185

            
186
    /* We index from 1 to leave room for data->header */
187
1200
    data[1].point.x = x;
188
1200
    data[1].point.y = y;
189

            
190
1200
    cpp->data += data->header.length;
191

            
192
1200
    return CAIRO_STATUS_SUCCESS;
193
}
194

            
195
static cairo_status_t
196
766
_cpp_curve_to (void			*closure,
197
	       const cairo_point_t	*p1,
198
	       const cairo_point_t	*p2,
199
	       const cairo_point_t	*p3)
200
{
201
766
    cpp_t *cpp = closure;
202
766
    cairo_path_data_t *data = cpp->data;
203
    double x1, y1;
204
    double x2, y2;
205
    double x3, y3;
206

            
207
766
    x1 = _cairo_fixed_to_double (p1->x);
208
766
    y1 = _cairo_fixed_to_double (p1->y);
209
766
    _cairo_backend_to_user (cpp->cr, &x1, &y1);
210

            
211
766
    x2 = _cairo_fixed_to_double (p2->x);
212
766
    y2 = _cairo_fixed_to_double (p2->y);
213
766
    _cairo_backend_to_user (cpp->cr, &x2, &y2);
214

            
215
766
    x3 = _cairo_fixed_to_double (p3->x);
216
766
    y3 = _cairo_fixed_to_double (p3->y);
217
766
    _cairo_backend_to_user (cpp->cr, &x3, &y3);
218

            
219
766
    data->header.type = CAIRO_PATH_CURVE_TO;
220
766
    data->header.length = 4;
221

            
222
    /* We index from 1 to leave room for data->header */
223
766
    data[1].point.x = x1;
224
766
    data[1].point.y = y1;
225

            
226
766
    data[2].point.x = x2;
227
766
    data[2].point.y = y2;
228

            
229
766
    data[3].point.x = x3;
230
766
    data[3].point.y = y3;
231

            
232
766
    cpp->data += data->header.length;
233

            
234
766
    return CAIRO_STATUS_SUCCESS;
235
}
236

            
237
static cairo_status_t
238
304
_cpp_close_path (void *closure)
239
{
240
304
    cpp_t *cpp = closure;
241
304
    cairo_path_data_t *data = cpp->data;
242

            
243
304
    data->header.type = CAIRO_PATH_CLOSE_PATH;
244
304
    data->header.length = 1;
245

            
246
304
    cpp->data += data->header.length;
247

            
248
304
    return CAIRO_STATUS_SUCCESS;
249
}
250

            
251
static cairo_status_t
252
453
_cairo_path_populate (cairo_path_t		*path,
253
		      cairo_path_fixed_t	*path_fixed,
254
		      cairo_t			*cr,
255
		      cairo_bool_t		 flatten)
256
{
257
    cairo_status_t status;
258
    cpp_t cpp;
259

            
260
453
    cpp.data = path->data;
261
453
    cpp.cr = cr;
262

            
263
453
    if (flatten) {
264
12
	status = _cairo_path_fixed_interpret_flat (path_fixed,
265
						   _cpp_move_to,
266
						   _cpp_line_to,
267
						   _cpp_close_path,
268
						   &cpp,
269
						   cairo_get_tolerance (cr));
270
    } else {
271
441
	status = _cairo_path_fixed_interpret (path_fixed,
272
					  _cpp_move_to,
273
					  _cpp_line_to,
274
					  _cpp_curve_to,
275
					  _cpp_close_path,
276
					  &cpp);
277
    }
278

            
279
453
    if (unlikely (status))
280
	return status;
281

            
282
    /* Sanity check the count */
283
453
    assert (cpp.data - path->data == path->num_data);
284

            
285
453
    return CAIRO_STATUS_SUCCESS;
286
}
287

            
288
cairo_path_t *
289
16
_cairo_path_create_in_error (cairo_status_t status)
290
{
291
    cairo_path_t *path;
292

            
293
    /* special case NO_MEMORY so as to avoid allocations */
294
16
    if (status == CAIRO_STATUS_NO_MEMORY)
295
	return (cairo_path_t*) &_cairo_path_nil;
296

            
297
16
    path = _cairo_calloc (sizeof (cairo_path_t));
298
16
    if (unlikely (path == NULL)) {
299
	_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
300
	return (cairo_path_t*) &_cairo_path_nil;
301
    }
302

            
303
16
    path->num_data = 0;
304
16
    path->data = NULL;
305
16
    path->status = status;
306

            
307
16
    return path;
308
}
309

            
310
static cairo_path_t *
311
456
_cairo_path_create_internal (cairo_path_fixed_t *path_fixed,
312
			     cairo_t		*cr,
313
			     cairo_bool_t	 flatten)
314
{
315
    cairo_path_t *path;
316

            
317
456
    path = _cairo_calloc (sizeof (cairo_path_t));
318
456
    if (unlikely (path == NULL)) {
319
	_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
320
	return (cairo_path_t*) &_cairo_path_nil;
321
    }
322

            
323
456
    path->num_data = _cairo_path_count (path, path_fixed,
324
					cairo_get_tolerance (cr),
325
					flatten);
326
456
    if (path->num_data < 0) {
327
	free (path);
328
	return (cairo_path_t*) &_cairo_path_nil;
329
    }
330

            
331
456
    if (path->num_data) {
332
453
	path->data = _cairo_malloc_ab (path->num_data,
333
				       sizeof (cairo_path_data_t));
334
453
	if (unlikely (path->data == NULL)) {
335
	    free (path);
336
	    _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
337
	    return (cairo_path_t*) &_cairo_path_nil;
338
	}
339

            
340
453
	path->status = _cairo_path_populate (path, path_fixed, cr, flatten);
341
    } else {
342
3
	path->data = NULL;
343
3
	path->status = CAIRO_STATUS_SUCCESS;
344
    }
345

            
346
456
    return path;
347
}
348

            
349
/**
350
 * cairo_path_destroy:
351
 * @path: a path previously returned by either cairo_copy_path() or
352
 * cairo_copy_path_flat().
353
 *
354
 * Immediately releases all memory associated with @path. After a call
355
 * to cairo_path_destroy() the @path pointer is no longer valid and
356
 * should not be used further.
357
 *
358
 * Note: cairo_path_destroy() should only be called with a
359
 * pointer to a #cairo_path_t returned by a cairo function. Any path
360
 * that is created manually (ie. outside of cairo) should be destroyed
361
 * manually as well.
362
 *
363
 * Since: 1.0
364
 **/
365
void
366
472
cairo_path_destroy (cairo_path_t *path)
367
{
368
472
    if (path == NULL || path == &_cairo_path_nil)
369
	return;
370

            
371
472
    free (path->data);
372

            
373
472
    free (path);
374
}
375

            
376
/**
377
 * _cairo_path_create:
378
 * @path: a fixed-point, device-space path to be converted and copied
379
 * @cr: the current graphics context
380
 *
381
 * Creates a user-space #cairo_path_t copy of the given device-space
382
 * @path. The @cr parameter provides the inverse CTM for the
383
 * conversion.
384
 *
385
 * Return value: the new copy of the path. If there is insufficient
386
 * memory a pointer to a special static nil #cairo_path_t will be
387
 * returned instead with status==%CAIRO_STATUS_NO_MEMORY and
388
 * data==%NULL.
389
 **/
390
cairo_path_t *
391
444
_cairo_path_create (cairo_path_fixed_t	*path,
392
		    cairo_t		*cr)
393
{
394
444
    return _cairo_path_create_internal (path, cr, FALSE);
395
}
396

            
397
/**
398
 * _cairo_path_create_flat:
399
 * @path: a fixed-point, device-space path to be flattened, converted and copied
400
 * @cr: the current graphics context
401
 *
402
 * Creates a flattened, user-space #cairo_path_t copy of the given
403
 * device-space @path. The @cr parameter provide the inverse CTM
404
 * for the conversion, as well as the tolerance value to control the
405
 * accuracy of the flattening.
406
 *
407
 * Return value: the flattened copy of the path. If there is insufficient
408
 * memory a pointer to a special static nil #cairo_path_t will be
409
 * returned instead with status==%CAIRO_STATUS_NO_MEMORY and
410
 * data==%NULL.
411
 **/
412
cairo_path_t *
413
12
_cairo_path_create_flat (cairo_path_fixed_t *path,
414
			 cairo_t	    *cr)
415
{
416
12
    return _cairo_path_create_internal (path, cr, TRUE);
417
}
418

            
419
/**
420
 * _cairo_path_append_to_context:
421
 * @path: the path data to be appended
422
 * @cr: a cairo context
423
 *
424
 * Append @path to the current path within @cr.
425
 *
426
 * Return value: %CAIRO_STATUS_INVALID_PATH_DATA if the data in @path
427
 * is invalid, and %CAIRO_STATUS_SUCCESS otherwise.
428
 **/
429
cairo_status_t
430
466
_cairo_path_append_to_context (const cairo_path_t	*path,
431
			       cairo_t			*cr)
432
{
433
    const cairo_path_data_t *p, *end;
434

            
435
466
    end = &path->data[path->num_data];
436
3522
    for (p = &path->data[0]; p < end; p += p->header.length) {
437
3057
	switch (p->header.type) {
438
790
	case CAIRO_PATH_MOVE_TO:
439
790
	    if (unlikely (p->header.length < 2))
440
1
		return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
441

            
442
789
	    cairo_move_to (cr, p[1].point.x, p[1].point.y);
443
789
	    break;
444

            
445
1182
	case CAIRO_PATH_LINE_TO:
446
1182
	    if (unlikely (p->header.length < 2))
447
		return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
448

            
449
1182
	    cairo_line_to (cr, p[1].point.x, p[1].point.y);
450
1182
	    break;
451

            
452
766
	case CAIRO_PATH_CURVE_TO:
453
766
	    if (unlikely (p->header.length < 4))
454
		return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
455

            
456
766
	    cairo_curve_to (cr,
457
766
			    p[1].point.x, p[1].point.y,
458
766
			    p[2].point.x, p[2].point.y,
459
766
			    p[3].point.x, p[3].point.y);
460
766
	    break;
461

            
462
319
	case CAIRO_PATH_CLOSE_PATH:
463
319
	    if (unlikely (p->header.length < 1))
464
		return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
465

            
466
319
	    cairo_close_path (cr);
467
319
	    break;
468

            
469
	default:
470
	    return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
471
	}
472

            
473
3056
	if (unlikely (cr->status))
474
	    return cr->status;
475
    }
476

            
477
465
    return CAIRO_STATUS_SUCCESS;
478
}