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[libsvgtiny.git] / src / svgtiny_gradient.c
1 /*
2 * This file is part of Libsvgtiny
3 * Licensed under the MIT License,
4 * http://opensource.org/licenses/mit-license.php
5 * Copyright 2008 James Bursa <james@semichrome.net>
6 */
7
8 #include <assert.h>
9 #include <math.h>
10 #include <string.h>
11 #include "svgtiny.h"
12 #include "svgtiny_internal.h"
13
14 #undef GRADIENT_DEBUG
15
16 static svgtiny_code svgtiny_parse_linear_gradient(xmlNode *linear,
17 struct svgtiny_parse_state *state);
18 static float svgtiny_parse_gradient_offset(const char *s);
19 static void svgtiny_path_bbox(float *p, unsigned int n,
20 float *x0, float *y0, float *x1, float *y1);
21 static void svgtiny_invert_matrix(float *m, float *inv);
22
23
24 /**
25 * Find a gradient by id and parse it.
26 */
27
28 void svgtiny_find_gradient(const char *id, struct svgtiny_parse_state *state)
29 {
30 xmlNode *gradient;
31
32 fprintf(stderr, "svgtiny_find_gradient: id \"%s\"\n", id);
33
34 state->linear_gradient_stop_count = 0;
35 state->gradient_x1 = "0%";
36 state->gradient_y1 = "0%";
37 state->gradient_x2 = "100%";
38 state->gradient_y2 = "0%";
39 state->gradient_user_space_on_use = false;
40 state->gradient_transform.a = 1;
41 state->gradient_transform.b = 0;
42 state->gradient_transform.c = 0;
43 state->gradient_transform.d = 1;
44 state->gradient_transform.e = 0;
45 state->gradient_transform.f = 0;
46
47 gradient = svgtiny_find_element_by_id(
48 (xmlNode *) state->document, id);
49 fprintf(stderr, "gradient %p\n", (void *) gradient);
50 if (!gradient) {
51 fprintf(stderr, "gradient \"%s\" not found\n", id);
52 return;
53 }
54
55 fprintf(stderr, "gradient name \"%s\"\n", gradient->name);
56 if (strcmp((const char *) gradient->name, "linearGradient") == 0) {
57 svgtiny_parse_linear_gradient(gradient, state);
58 }
59 }
60
61
62 /**
63 * Parse a <linearGradient> element node.
64 *
65 * http://www.w3.org/TR/SVG11/pservers#LinearGradients
66 */
67
68 svgtiny_code svgtiny_parse_linear_gradient(xmlNode *linear,
69 struct svgtiny_parse_state *state)
70 {
71 unsigned int i = 0;
72 xmlNode *stop;
73 xmlAttr *attr;
74 xmlAttr *href = xmlHasProp(linear, (const xmlChar *) "href");
75 if (href && href->children->content[0] == '#')
76 svgtiny_find_gradient((const char *) href->children->content
77 + 1, state);
78
79 for (attr = linear->properties; attr; attr = attr->next) {
80 const char *name = (const char *) attr->name;
81 const char *content = (const char *) attr->children->content;
82 if (strcmp(name, "x1") == 0)
83 state->gradient_x1 = content;
84 else if (strcmp(name, "y1") == 0)
85 state->gradient_y1 = content;
86 else if (strcmp(name, "x2") == 0)
87 state->gradient_x2 = content;
88 else if (strcmp(name, "y2") == 0)
89 state->gradient_y2 = content;
90 else if (strcmp(name, "gradientUnits") == 0)
91 state->gradient_user_space_on_use =
92 strcmp(content, "userSpaceOnUse") == 0;
93 else if (strcmp(name, "gradientTransform") == 0) {
94 float a = 1, b = 0, c = 0, d = 1, e = 0, f = 0;
95 char *s = strdup(content);
96 if (!s)
97 return svgtiny_OUT_OF_MEMORY;
98 svgtiny_parse_transform(s, &a, &b, &c, &d, &e, &f);
99 free(s);
100 fprintf(stderr, "transform %g %g %g %g %g %g\n",
101 a, b, c, d, e, f);
102 state->gradient_transform.a = a;
103 state->gradient_transform.b = b;
104 state->gradient_transform.c = c;
105 state->gradient_transform.d = d;
106 state->gradient_transform.e = e;
107 state->gradient_transform.f = f;
108 }
109 }
110
111 for (stop = linear->children; stop; stop = stop->next) {
112 float offset = -1;
113 svgtiny_colour color = svgtiny_TRANSPARENT;
114
115 if (stop->type != XML_ELEMENT_NODE)
116 continue;
117 if (strcmp((const char *) stop->name, "stop") != 0)
118 continue;
119
120 for (attr = stop->properties; attr;
121 attr = attr->next) {
122 const char *name = (const char *) attr->name;
123 const char *content =
124 (const char *) attr->children->content;
125 if (strcmp(name, "offset") == 0)
126 offset = svgtiny_parse_gradient_offset(content);
127 else if (strcmp(name, "stop-color") == 0)
128 svgtiny_parse_color(content, &color, state);
129 else if (strcmp(name, "style") == 0) {
130 const char *s;
131 char *value;
132 if ((s = strstr(content, "stop-color:"))) {
133 s += 11;
134 while (*s == ' ')
135 s++;
136 value = strndup(s, strcspn(s, "; "));
137 svgtiny_parse_color(value, &color,
138 state);
139 free(value);
140 }
141 }
142 }
143
144 if (offset != -1 && color != svgtiny_TRANSPARENT) {
145 fprintf(stderr, "stop %g %x\n", offset, color);
146 state->gradient_stop[i].offset = offset;
147 state->gradient_stop[i].color = color;
148 i++;
149 }
150
151 if (i == svgtiny_MAX_STOPS)
152 break;
153 }
154
155 if (i)
156 state->linear_gradient_stop_count = i;
157
158 return svgtiny_OK;
159 }
160
161
162 float svgtiny_parse_gradient_offset(const char *s)
163 {
164 int num_length = strspn(s, "0123456789+-.");
165 const char *unit = s + num_length;
166 float n = atof((const char *) s);
167
168 if (unit[0] == 0)
169 ;
170 else if (unit[0] == '%')
171 n /= 100.0;
172 else
173 return -1;
174
175 if (n < 0)
176 n = 0;
177 if (1 < n)
178 n = 1;
179 return n;
180 }
181
182
183 /**
184 * Add a path with a linear gradient fill to the svgtiny_diagram.
185 */
186
187 svgtiny_code svgtiny_add_path_linear_gradient(float *p, unsigned int n,
188 struct svgtiny_parse_state *state)
189 {
190 struct grad_point {
191 float x, y, r;
192 };
193 float object_x0, object_y0, object_x1, object_y1;
194 float gradient_x0, gradient_y0, gradient_x1, gradient_y1,
195 gradient_dx, gradient_dy;
196 float trans[6];
197 unsigned int steps = 10;
198 float x0 = 0, y0 = 0, x0_trans, y0_trans, r0; /* segment start point */
199 float x1, y1, x1_trans, y1_trans, r1; /* segment end point */
200 /* segment control points (beziers only) */
201 float c0x = 0, c0y = 0, c1x = 0, c1y = 0;
202 float gradient_norm_squared;
203 struct svgtiny_list *pts;
204 float min_r = 1000;
205 unsigned int min_pt = 0;
206 unsigned int j;
207 unsigned int stop_count;
208 unsigned int current_stop;
209 float last_stop_r;
210 float current_stop_r;
211 int red0, green0, blue0, red1, green1, blue1;
212 unsigned int t, a, b;
213
214 /* determine object bounding box */
215 svgtiny_path_bbox(p, n, &object_x0, &object_y0, &object_x1, &object_y1);
216 #ifdef GRADIENT_DEBUG
217 fprintf(stderr, "object bbox: (%g %g) (%g %g)\n",
218 object_x0, object_y0, object_x1, object_y1);
219 #endif
220
221 /* compute gradient vector */
222 fprintf(stderr, "x1 %s, y1 %s, x2 %s, y2 %s\n",
223 state->gradient_x1, state->gradient_y1,
224 state->gradient_x2, state->gradient_y2);
225 if (!state->gradient_user_space_on_use) {
226 gradient_x0 = object_x0 +
227 svgtiny_parse_length(state->gradient_x1,
228 object_x1 - object_x0, *state);
229 gradient_y0 = object_y0 +
230 svgtiny_parse_length(state->gradient_y1,
231 object_y1 - object_y0, *state);
232 gradient_x1 = object_x0 +
233 svgtiny_parse_length(state->gradient_x2,
234 object_x1 - object_x0, *state);
235 gradient_y1 = object_y0 +
236 svgtiny_parse_length(state->gradient_y2,
237 object_y1 - object_y0, *state);
238 } else {
239 gradient_x0 = svgtiny_parse_length(state->gradient_x1,
240 state->viewport_width, *state);
241 gradient_y0 = svgtiny_parse_length(state->gradient_y1,
242 state->viewport_height, *state);
243 gradient_x1 = svgtiny_parse_length(state->gradient_x2,
244 state->viewport_width, *state);
245 gradient_y1 = svgtiny_parse_length(state->gradient_y2,
246 state->viewport_height, *state);
247 }
248 gradient_dx = gradient_x1 - gradient_x0;
249 gradient_dy = gradient_y1 - gradient_y0;
250 #ifdef GRADIENT_DEBUG
251 fprintf(stderr, "gradient vector: (%g %g) => (%g %g)\n",
252 gradient_x0, gradient_y0, gradient_x1, gradient_y1);
253 #endif
254
255 /* show theoretical gradient strips for debugging */
256 /*unsigned int strips = 10;
257 for (unsigned int z = 0; z != strips; z++) {
258 float f0, fd, strip_x0, strip_y0, strip_dx, strip_dy;
259 f0 = (float) z / (float) strips;
260 fd = (float) 1 / (float) strips;
261 strip_x0 = gradient_x0 + f0 * gradient_dx;
262 strip_y0 = gradient_y0 + f0 * gradient_dy;
263 strip_dx = fd * gradient_dx;
264 strip_dy = fd * gradient_dy;
265 fprintf(stderr, "strip %i vector: (%g %g) + (%g %g)\n",
266 z, strip_x0, strip_y0, strip_dx, strip_dy);
267
268 float *p = malloc(13 * sizeof p[0]);
269 if (!p)
270 return svgtiny_OUT_OF_MEMORY;
271 p[0] = svgtiny_PATH_MOVE;
272 p[1] = strip_x0 + (strip_dy * 3);
273 p[2] = strip_y0 - (strip_dx * 3);
274 p[3] = svgtiny_PATH_LINE;
275 p[4] = p[1] + strip_dx;
276 p[5] = p[2] + strip_dy;
277 p[6] = svgtiny_PATH_LINE;
278 p[7] = p[4] - (strip_dy * 6);
279 p[8] = p[5] + (strip_dx * 6);
280 p[9] = svgtiny_PATH_LINE;
281 p[10] = p[7] - strip_dx;
282 p[11] = p[8] - strip_dy;
283 p[12] = svgtiny_PATH_CLOSE;
284 svgtiny_transform_path(p, 13, state);
285 struct svgtiny_shape *shape = svgtiny_add_shape(state);
286 if (!shape) {
287 free(p);
288 return svgtiny_OUT_OF_MEMORY;
289 }
290 shape->path = p;
291 shape->path_length = 13;
292 shape->fill = svgtiny_TRANSPARENT;
293 shape->stroke = svgtiny_RGB(0, 0xff, 0);
294 state->diagram->shape_count++;
295 }*/
296
297 /* invert gradient transform for applying to vertices */
298 svgtiny_invert_matrix(&state->gradient_transform.a, trans);
299 fprintf(stderr, "inverse transform %g %g %g %g %g %g\n",
300 trans[0], trans[1], trans[2], trans[3],
301 trans[4], trans[5]);
302
303 /* compute points on the path for triangle vertices */
304 /* r, r0, r1 are distance along gradient vector */
305 gradient_norm_squared = gradient_dx * gradient_dx +
306 gradient_dy * gradient_dy;
307 pts = svgtiny_list_create(
308 sizeof (struct grad_point));
309 if (!pts)
310 return svgtiny_OUT_OF_MEMORY;
311 for (j = 0; j != n; ) {
312 int segment_type = (int) p[j];
313 struct grad_point *point;
314 unsigned int z;
315
316 if (segment_type == svgtiny_PATH_MOVE) {
317 x0 = p[j + 1];
318 y0 = p[j + 2];
319 j += 3;
320 continue;
321 }
322
323 assert(segment_type == svgtiny_PATH_CLOSE ||
324 segment_type == svgtiny_PATH_LINE ||
325 segment_type == svgtiny_PATH_BEZIER);
326
327 /* start point (x0, y0) */
328 x0_trans = trans[0]*x0 + trans[2]*y0 + trans[4];
329 y0_trans = trans[1]*x0 + trans[3]*y0 + trans[5];
330 r0 = ((x0_trans - gradient_x0) * gradient_dx +
331 (y0_trans - gradient_y0) * gradient_dy) /
332 gradient_norm_squared;
333 point = svgtiny_list_push(pts);
334 if (!point) {
335 svgtiny_list_free(pts);
336 return svgtiny_OUT_OF_MEMORY;
337 }
338 point->x = x0;
339 point->y = y0;
340 point->r = r0;
341 if (r0 < min_r) {
342 min_r = r0;
343 min_pt = svgtiny_list_size(pts) - 1;
344 }
345
346 /* end point (x1, y1) */
347 if (segment_type == svgtiny_PATH_LINE) {
348 x1 = p[j + 1];
349 y1 = p[j + 2];
350 j += 3;
351 } else if (segment_type == svgtiny_PATH_CLOSE) {
352 x1 = p[1];
353 y1 = p[2];
354 j++;
355 } else /* svgtiny_PATH_BEZIER */ {
356 c0x = p[j + 1];
357 c0y = p[j + 2];
358 c1x = p[j + 3];
359 c1y = p[j + 4];
360 x1 = p[j + 5];
361 y1 = p[j + 6];
362 j += 7;
363 }
364 x1_trans = trans[0]*x1 + trans[2]*y1 + trans[4];
365 y1_trans = trans[1]*x1 + trans[3]*y1 + trans[5];
366 r1 = ((x1_trans - gradient_x0) * gradient_dx +
367 (y1_trans - gradient_y0) * gradient_dy) /
368 gradient_norm_squared;
369
370 /* determine steps from change in r */
371 steps = ceilf(fabsf(r1 - r0) / 0.05);
372 if (steps == 0)
373 steps = 1;
374 fprintf(stderr, "r0 %g, r1 %g, steps %i\n",
375 r0, r1, steps);
376
377 /* loop through intermediate points */
378 for (z = 1; z != steps; z++) {
379 float t, x, y, x_trans, y_trans, r;
380 struct grad_point *point;
381 t = (float) z / (float) steps;
382 if (segment_type == svgtiny_PATH_BEZIER) {
383 x = (1-t) * (1-t) * (1-t) * x0 +
384 3 * t * (1-t) * (1-t) * c0x +
385 3 * t * t * (1-t) * c1x +
386 t * t * t * x1;
387 y = (1-t) * (1-t) * (1-t) * y0 +
388 3 * t * (1-t) * (1-t) * c0y +
389 3 * t * t * (1-t) * c1y +
390 t * t * t * y1;
391 } else {
392 x = (1-t) * x0 + t * x1;
393 y = (1-t) * y0 + t * y1;
394 }
395 x_trans = trans[0]*x + trans[2]*y + trans[4];
396 y_trans = trans[1]*x + trans[3]*y + trans[5];
397 r = ((x_trans - gradient_x0) * gradient_dx +
398 (y_trans - gradient_y0) * gradient_dy) /
399 gradient_norm_squared;
400 fprintf(stderr, "(%g %g [%g]) ", x, y, r);
401 point = svgtiny_list_push(pts);
402 if (!point) {
403 svgtiny_list_free(pts);
404 return svgtiny_OUT_OF_MEMORY;
405 }
406 point->x = x;
407 point->y = y;
408 point->r = r;
409 if (r < min_r) {
410 min_r = r;
411 min_pt = svgtiny_list_size(pts) - 1;
412 }
413 }
414 fprintf(stderr, "\n");
415
416 /* next segment start point is this segment end point */
417 x0 = x1;
418 y0 = y1;
419 }
420 fprintf(stderr, "pts size %i, min_pt %i, min_r %.3f\n",
421 svgtiny_list_size(pts), min_pt, min_r);
422
423 /* render triangles */
424 stop_count = state->linear_gradient_stop_count;
425 assert(2 <= stop_count);
426 current_stop = 0;
427 last_stop_r = 0;
428 current_stop_r = state->gradient_stop[0].offset;
429 red0 = red1 = svgtiny_RED(state->gradient_stop[0].color);
430 green0 = green1 = svgtiny_GREEN(state->gradient_stop[0].color);
431 blue0 = blue1 = svgtiny_BLUE(state->gradient_stop[0].color);
432 t = min_pt;
433 a = (min_pt + 1) % svgtiny_list_size(pts);
434 b = min_pt == 0 ? svgtiny_list_size(pts) - 1 : min_pt - 1;
435 while (a != b) {
436 struct grad_point *point_t = svgtiny_list_get(pts, t);
437 struct grad_point *point_a = svgtiny_list_get(pts, a);
438 struct grad_point *point_b = svgtiny_list_get(pts, b);
439 float mean_r = (point_t->r + point_a->r + point_b->r) / 3;
440 float *p;
441 struct svgtiny_shape *shape;
442 /*fprintf(stderr, "triangle: t %i %.3f a %i %.3f b %i %.3f "
443 "mean_r %.3f\n",
444 t, pts[t].r, a, pts[a].r, b, pts[b].r,
445 mean_r);*/
446 while (current_stop != stop_count && current_stop_r < mean_r) {
447 current_stop++;
448 if (current_stop == stop_count)
449 break;
450 red0 = red1;
451 green0 = green1;
452 blue0 = blue1;
453 red1 = svgtiny_RED(state->
454 gradient_stop[current_stop].color);
455 green1 = svgtiny_GREEN(state->
456 gradient_stop[current_stop].color);
457 blue1 = svgtiny_BLUE(state->
458 gradient_stop[current_stop].color);
459 last_stop_r = current_stop_r;
460 current_stop_r = state->
461 gradient_stop[current_stop].offset;
462 }
463 p = malloc(10 * sizeof p[0]);
464 if (!p)
465 return svgtiny_OUT_OF_MEMORY;
466 p[0] = svgtiny_PATH_MOVE;
467 p[1] = point_t->x;
468 p[2] = point_t->y;
469 p[3] = svgtiny_PATH_LINE;
470 p[4] = point_a->x;
471 p[5] = point_a->y;
472 p[6] = svgtiny_PATH_LINE;
473 p[7] = point_b->x;
474 p[8] = point_b->y;
475 p[9] = svgtiny_PATH_CLOSE;
476 svgtiny_transform_path(p, 10, state);
477 shape = svgtiny_add_shape(state);
478 if (!shape) {
479 free(p);
480 return svgtiny_OUT_OF_MEMORY;
481 }
482 shape->path = p;
483 shape->path_length = 10;
484 /*shape->fill = svgtiny_TRANSPARENT;*/
485 if (current_stop == 0)
486 shape->fill = state->gradient_stop[0].color;
487 else if (current_stop == stop_count)
488 shape->fill = state->
489 gradient_stop[stop_count - 1].color;
490 else {
491 float stop_r = (mean_r - last_stop_r) /
492 (current_stop_r - last_stop_r);
493 shape->fill = svgtiny_RGB(
494 (int) ((1 - stop_r) * red0 + stop_r * red1),
495 (int) ((1 - stop_r) * green0 + stop_r * green1),
496 (int) ((1 - stop_r) * blue0 + stop_r * blue1));
497 }
498 shape->stroke = svgtiny_TRANSPARENT;
499 #ifdef GRADIENT_DEBUG
500 shape->stroke = svgtiny_RGB(0, 0, 0xff);
501 #endif
502 state->diagram->shape_count++;
503 if (point_a->r < point_b->r) {
504 t = a;
505 a = (a + 1) % svgtiny_list_size(pts);
506 } else {
507 t = b;
508 b = b == 0 ? svgtiny_list_size(pts) - 1 : b - 1;
509 }
510 }
511
512 /* render gradient vector for debugging */
513 #ifdef GRADIENT_DEBUG
514 {
515 float *p = malloc(7 * sizeof p[0]);
516 if (!p)
517 return svgtiny_OUT_OF_MEMORY;
518 p[0] = svgtiny_PATH_MOVE;
519 p[1] = gradient_x0;
520 p[2] = gradient_y0;
521 p[3] = svgtiny_PATH_LINE;
522 p[4] = gradient_x1;
523 p[5] = gradient_y1;
524 p[6] = svgtiny_PATH_CLOSE;
525 svgtiny_transform_path(p, 7, state);
526 struct svgtiny_shape *shape = svgtiny_add_shape(state);
527 if (!shape) {
528 free(p);
529 return svgtiny_OUT_OF_MEMORY;
530 }
531 shape->path = p;
532 shape->path_length = 7;
533 shape->fill = svgtiny_TRANSPARENT;
534 shape->stroke = svgtiny_RGB(0xff, 0, 0);
535 state->diagram->shape_count++;
536 }
537 #endif
538
539 /* render triangle vertices with r values for debugging */
540 #ifdef GRADIENT_DEBUG
541 for (unsigned int i = 0; i != pts->size; i++) {
542 struct grad_point *point = svgtiny_list_get(pts, i);
543 struct svgtiny_shape *shape = svgtiny_add_shape(state);
544 if (!shape)
545 return svgtiny_OUT_OF_MEMORY;
546 char *text = malloc(20);
547 if (!text)
548 return svgtiny_OUT_OF_MEMORY;
549 sprintf(text, "%i=%.3f", i, point->r);
550 shape->text = text;
551 shape->text_x = state->ctm.a * point->x +
552 state->ctm.c * point->y + state->ctm.e;
553 shape->text_y = state->ctm.b * point->x +
554 state->ctm.d * point->y + state->ctm.f;
555 shape->fill = svgtiny_RGB(0, 0, 0);
556 shape->stroke = svgtiny_TRANSPARENT;
557 state->diagram->shape_count++;
558 }
559 #endif
560
561 /* plot actual path outline */
562 if (state->stroke != svgtiny_TRANSPARENT) {
563 struct svgtiny_shape *shape;
564 svgtiny_transform_path(p, n, state);
565
566 shape = svgtiny_add_shape(state);
567 if (!shape) {
568 free(p);
569 return svgtiny_OUT_OF_MEMORY;
570 }
571 shape->path = p;
572 shape->path_length = n;
573 shape->fill = svgtiny_TRANSPARENT;
574 state->diagram->shape_count++;
575 } else {
576 free(p);
577 }
578
579 svgtiny_list_free(pts);
580
581 return svgtiny_OK;
582 }
583
584
585 /**
586 * Get the bounding box of path.
587 */
588
589 void svgtiny_path_bbox(float *p, unsigned int n,
590 float *x0, float *y0, float *x1, float *y1)
591 {
592 unsigned int j;
593
594 *x0 = *x1 = p[1];
595 *y0 = *y1 = p[2];
596
597 for (j = 0; j != n; ) {
598 unsigned int points = 0;
599 unsigned int k;
600 switch ((int) p[j]) {
601 case svgtiny_PATH_MOVE:
602 case svgtiny_PATH_LINE:
603 points = 1;
604 break;
605 case svgtiny_PATH_CLOSE:
606 points = 0;
607 break;
608 case svgtiny_PATH_BEZIER:
609 points = 3;
610 break;
611 default:
612 assert(0);
613 }
614 j++;
615 for (k = 0; k != points; k++) {
616 float x = p[j], y = p[j + 1];
617 if (x < *x0)
618 *x0 = x;
619 else if (*x1 < x)
620 *x1 = x;
621 if (y < *y0)
622 *y0 = y;
623 else if (*y1 < y)
624 *y1 = y;
625 j += 2;
626 }
627 }
628 }
629
630
631 /**
632 * Invert a transformation matrix.
633 */
634 void svgtiny_invert_matrix(float *m, float *inv)
635 {
636 float determinant = m[0]*m[3] - m[1]*m[2];
637 inv[0] = m[3] / determinant;
638 inv[1] = -m[1] / determinant;
639 inv[2] = -m[2] / determinant;
640 inv[3] = m[0] / determinant;
641 inv[4] = (m[2]*m[5] - m[3]*m[4]) / determinant;
642 inv[5] = (m[1]*m[4] - m[0]*m[5]) / determinant;
643 }
644
645
646 /**
647 * Find an element in the document by id.
648 */
649
650 xmlNode *svgtiny_find_element_by_id(xmlNode *node, const char *id)
651 {
652 xmlNode *child;
653 xmlNode *found;
654
655 for (child = node->children; child; child = child->next) {
656 xmlAttr *attr;
657 if (child->type != XML_ELEMENT_NODE)
658 continue;
659 attr = xmlHasProp(child, (const xmlChar *) "id");
660 if (attr && strcmp(id, (const char *) attr->children->content)
661 == 0)
662 return child;
663 found = svgtiny_find_element_by_id(child, id);
664 if (found)
665 return found;
666 }
667
668 return 0;
669 }
670
Development fork of https://git.netsurf-browser.org/libsvgtiny.git