1 /*
2 * <sodipodi:star> implementation
3 *
4 * Authors:
5 * Mitsuru Oka <oka326@parkcity.ne.jp>
6 * Lauris Kaplinski <lauris@kaplinski.com>
7 * bulia byak <buliabyak@users.sf.net>
8 * Abhishek Sharma
9 *
10 * Copyright (C) 1999-2002 Lauris Kaplinski
11 * Copyright (C) 2000-2001 Ximian, Inc.
12 *
13 * Released under GNU GPL, read the file 'COPYING' for more information
14 */
16 #ifdef HAVE_CONFIG_H
17 # include "config.h"
18 #endif
20 #include <cstring>
21 #include <string>
22 #include <glibmm/i18n.h>
24 #include "svg/svg.h"
25 #include "attributes.h"
26 #include "display/curve.h"
27 #include "xml/repr.h"
28 #include "document.h"
30 #include <2geom/pathvector.h>
32 #include "sp-star.h"
34 static void sp_star_class_init (SPStarClass *klass);
35 static void sp_star_init (SPStar *star);
37 static void sp_star_build (SPObject * object, SPDocument * document, Inkscape::XML::Node * repr);
38 static Inkscape::XML::Node *sp_star_write (SPObject *object, Inkscape::XML::Document *doc, Inkscape::XML::Node *repr, guint flags);
39 static void sp_star_set (SPObject *object, unsigned int key, const gchar *value);
40 static void sp_star_update (SPObject *object, SPCtx *ctx, guint flags);
42 static gchar * sp_star_description (SPItem * item);
43 static void sp_star_snappoints(SPItem const *item, std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs);
45 static void sp_star_set_shape (SPShape *shape);
46 static void sp_star_update_patheffect (SPLPEItem *lpeitem, bool write);
48 static SPShapeClass *parent_class;
50 GType
51 sp_star_get_type (void)
52 {
53 static GType type = 0;
55 if (!type) {
56 GTypeInfo info = {
57 sizeof (SPStarClass),
58 NULL, NULL,
59 (GClassInitFunc) sp_star_class_init,
60 NULL, NULL,
61 sizeof (SPStar),
62 16,
63 (GInstanceInitFunc) sp_star_init,
64 NULL, /* value_table */
65 };
66 type = g_type_register_static (SP_TYPE_SHAPE, "SPStar", &info, (GTypeFlags)0);
67 }
68 return type;
69 }
71 static void
72 sp_star_class_init (SPStarClass *klass)
73 {
74 GObjectClass * gobject_class;
75 SPObjectClass * sp_object_class;
76 SPItemClass * item_class;
77 SPLPEItemClass * lpe_item_class;
78 SPShapeClass * shape_class;
80 gobject_class = (GObjectClass *) klass;
81 sp_object_class = (SPObjectClass *) klass;
82 item_class = (SPItemClass *) klass;
83 lpe_item_class = (SPLPEItemClass *) klass;
84 shape_class = (SPShapeClass *) klass;
86 parent_class = (SPShapeClass *)g_type_class_ref (SP_TYPE_SHAPE);
88 sp_object_class->build = sp_star_build;
89 sp_object_class->write = sp_star_write;
90 sp_object_class->set = sp_star_set;
91 sp_object_class->update = sp_star_update;
93 item_class->description = sp_star_description;
94 item_class->snappoints = sp_star_snappoints;
96 lpe_item_class->update_patheffect = sp_star_update_patheffect;
98 shape_class->set_shape = sp_star_set_shape;
99 }
101 static void
102 sp_star_init (SPStar * star)
103 {
104 star->sides = 5;
105 star->center = Geom::Point(0, 0);
106 star->r[0] = 1.0;
107 star->r[1] = 0.001;
108 star->arg[0] = star->arg[1] = 0.0;
109 star->flatsided = 0;
110 star->rounded = 0.0;
111 star->randomized = 0.0;
112 }
114 static void
115 sp_star_build (SPObject * object, SPDocument * document, Inkscape::XML::Node * repr)
116 {
117 if (((SPObjectClass *) parent_class)->build)
118 ((SPObjectClass *) parent_class)->build (object, document, repr);
120 object->readAttr( "sodipodi:cx" );
121 object->readAttr( "sodipodi:cy" );
122 object->readAttr( "sodipodi:sides" );
123 object->readAttr( "sodipodi:r1" );
124 object->readAttr( "sodipodi:r2" );
125 object->readAttr( "sodipodi:arg1" );
126 object->readAttr( "sodipodi:arg2" );
127 object->readAttr( "inkscape:flatsided" );
128 object->readAttr( "inkscape:rounded" );
129 object->readAttr( "inkscape:randomized" );
130 }
132 static Inkscape::XML::Node *
133 sp_star_write (SPObject *object, Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags)
134 {
135 SPStar *star = SP_STAR (object);
137 if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
138 repr = xml_doc->createElement("svg:path");
139 }
141 if (flags & SP_OBJECT_WRITE_EXT) {
142 repr->setAttribute("sodipodi:type", "star");
143 sp_repr_set_int (repr, "sodipodi:sides", star->sides);
144 sp_repr_set_svg_double(repr, "sodipodi:cx", star->center[Geom::X]);
145 sp_repr_set_svg_double(repr, "sodipodi:cy", star->center[Geom::Y]);
146 sp_repr_set_svg_double(repr, "sodipodi:r1", star->r[0]);
147 sp_repr_set_svg_double(repr, "sodipodi:r2", star->r[1]);
148 sp_repr_set_svg_double(repr, "sodipodi:arg1", star->arg[0]);
149 sp_repr_set_svg_double(repr, "sodipodi:arg2", star->arg[1]);
150 sp_repr_set_boolean (repr, "inkscape:flatsided", star->flatsided);
151 sp_repr_set_svg_double(repr, "inkscape:rounded", star->rounded);
152 sp_repr_set_svg_double(repr, "inkscape:randomized", star->randomized);
153 }
155 sp_star_set_shape ((SPShape *) star);
156 char *d = sp_svg_write_path (((SPShape *) star)->curve->get_pathvector());
157 repr->setAttribute("d", d);
158 g_free (d);
160 if (((SPObjectClass *) (parent_class))->write)
161 ((SPObjectClass *) (parent_class))->write (object, xml_doc, repr, flags);
163 return repr;
164 }
166 static void
167 sp_star_set (SPObject *object, unsigned int key, const gchar *value)
168 {
169 SVGLength::Unit unit;
171 SPStar *star = SP_STAR (object);
173 /* fixme: we should really collect updates */
174 switch (key) {
175 case SP_ATTR_SODIPODI_SIDES:
176 if (value) {
177 star->sides = atoi (value);
178 star->sides = NR_CLAMP(star->sides, 3, 1024);
179 } else {
180 star->sides = 5;
181 }
182 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
183 break;
184 case SP_ATTR_SODIPODI_CX:
185 if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->center[Geom::X]) ||
186 (unit == SVGLength::EM) ||
187 (unit == SVGLength::EX) ||
188 (unit == SVGLength::PERCENT)) {
189 star->center[Geom::X] = 0.0;
190 }
191 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
192 break;
193 case SP_ATTR_SODIPODI_CY:
194 if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->center[Geom::Y]) ||
195 (unit == SVGLength::EM) ||
196 (unit == SVGLength::EX) ||
197 (unit == SVGLength::PERCENT)) {
198 star->center[Geom::Y] = 0.0;
199 }
200 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
201 break;
202 case SP_ATTR_SODIPODI_R1:
203 if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->r[0]) ||
204 (unit == SVGLength::EM) ||
205 (unit == SVGLength::EX) ||
206 (unit == SVGLength::PERCENT)) {
207 star->r[0] = 1.0;
208 }
209 /* fixme: Need CLAMP (Lauris) */
210 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
211 break;
212 case SP_ATTR_SODIPODI_R2:
213 if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->r[1]) ||
214 (unit == SVGLength::EM) ||
215 (unit == SVGLength::EX) ||
216 (unit == SVGLength::PERCENT)) {
217 star->r[1] = 0.0;
218 }
219 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
220 return;
221 case SP_ATTR_SODIPODI_ARG1:
222 if (value) {
223 star->arg[0] = g_ascii_strtod (value, NULL);
224 } else {
225 star->arg[0] = 0.0;
226 }
227 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
228 break;
229 case SP_ATTR_SODIPODI_ARG2:
230 if (value) {
231 star->arg[1] = g_ascii_strtod (value, NULL);
232 } else {
233 star->arg[1] = 0.0;
234 }
235 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
236 break;
237 case SP_ATTR_INKSCAPE_FLATSIDED:
238 if (value && !strcmp (value, "true"))
239 star->flatsided = true;
240 else star->flatsided = false;
241 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
242 break;
243 case SP_ATTR_INKSCAPE_ROUNDED:
244 if (value) {
245 star->rounded = g_ascii_strtod (value, NULL);
246 } else {
247 star->rounded = 0.0;
248 }
249 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
250 break;
251 case SP_ATTR_INKSCAPE_RANDOMIZED:
252 if (value) {
253 star->randomized = g_ascii_strtod (value, NULL);
254 } else {
255 star->randomized = 0.0;
256 }
257 object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
258 break;
259 default:
260 if (((SPObjectClass *) parent_class)->set)
261 ((SPObjectClass *) parent_class)->set (object, key, value);
262 break;
263 }
264 }
266 static void
267 sp_star_update (SPObject *object, SPCtx *ctx, guint flags)
268 {
269 if (flags & (SP_OBJECT_MODIFIED_FLAG |
270 SP_OBJECT_STYLE_MODIFIED_FLAG |
271 SP_OBJECT_VIEWPORT_MODIFIED_FLAG)) {
272 ((SPShape *) object)->setShape ();
273 }
275 if (((SPObjectClass *) parent_class)->update)
276 ((SPObjectClass *) parent_class)->update (object, ctx, flags);
277 }
279 static void
280 sp_star_update_patheffect(SPLPEItem *lpeitem, bool write)
281 {
282 SPShape *shape = (SPShape *) lpeitem;
283 sp_star_set_shape(shape);
285 if (write) {
286 Inkscape::XML::Node *repr = SP_OBJECT_REPR(shape);
287 if ( shape->curve != NULL ) {
288 gchar *str = sp_svg_write_path(shape->curve->get_pathvector());
289 repr->setAttribute("d", str);
290 g_free(str);
291 } else {
292 repr->setAttribute("d", NULL);
293 }
294 }
296 ((SPObject *)shape)->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
297 }
299 static gchar *
300 sp_star_description (SPItem *item)
301 {
302 SPStar *star = SP_STAR (item);
304 // while there will never be less than 3 vertices, we still need to
305 // make calls to ngettext because the pluralization may be different
306 // for various numbers >=3. The singular form is used as the index.
307 if (star->flatsided == false )
308 return g_strdup_printf (ngettext("<b>Star</b> with %d vertex",
309 "<b>Star</b> with %d vertices",
310 star->sides), star->sides);
311 else
312 return g_strdup_printf (ngettext("<b>Polygon</b> with %d vertex",
313 "<b>Polygon</b> with %d vertices",
314 star->sides), star->sides);
315 }
317 /**
318 Returns a unit-length vector at 90 degrees to the direction from o to n
319 */
320 static Geom::Point
321 rot90_rel (Geom::Point o, Geom::Point n)
322 {
323 return ((1/Geom::L2(n - o)) * Geom::Point ((n - o)[Geom::Y], (o - n)[Geom::X]));
324 }
326 /**
327 Returns a unique 32 bit int for a given point.
328 Obvious (but acceptable for my purposes) limits to uniqueness:
329 - returned value for x,y repeats for x+n*1024,y+n*1024
330 - returned value is unchanged when the point is moved by less than 1/1024 of px
331 */
332 static guint32
333 point_unique_int (Geom::Point o)
334 {
335 return ((guint32)
336 65536 *
337 (((int) floor (o[Geom::X] * 64)) % 1024 + ((int) floor (o[Geom::X] * 1024)) % 64)
338 +
339 (((int) floor (o[Geom::Y] * 64)) % 1024 + ((int) floor (o[Geom::Y] * 1024)) % 64)
340 );
341 }
343 /**
344 Returns the next pseudorandom value using the Linear Congruential Generator algorithm (LCG)
345 with the parameters (m = 2^32, a = 69069, b = 1). These parameters give a full-period generator,
346 i.e. it is guaranteed to go through all integers < 2^32 (see http://random.mat.sbg.ac.at/~charly/server/server.html)
347 */
348 static inline guint32
349 lcg_next(guint32 const prev)
350 {
351 return (guint32) ( 69069 * prev + 1 );
352 }
354 /**
355 Returns a random number in the range [-0.5, 0.5) from the given seed, stepping the given number of steps from the seed.
356 */
357 static double
358 rnd (guint32 const seed, unsigned steps) {
359 guint32 lcg = seed;
360 for (; steps > 0; steps --)
361 lcg = lcg_next (lcg);
363 return ( lcg / 4294967296. ) - 0.5;
364 }
366 static Geom::Point
367 sp_star_get_curvepoint (SPStar *star, SPStarPoint point, gint index, bool previ)
368 {
369 // the point whose neighboring curve handle we're calculating
370 Geom::Point o = sp_star_get_xy (star, point, index);
372 // indices of previous and next points
373 gint pi = (index > 0)? (index - 1) : (star->sides - 1);
374 gint ni = (index < star->sides - 1)? (index + 1) : 0;
376 // the other point type
377 SPStarPoint other = (point == SP_STAR_POINT_KNOT2? SP_STAR_POINT_KNOT1 : SP_STAR_POINT_KNOT2);
379 // the neighbors of o; depending on flatsided, they're either the same type (polygon) or the other type (star)
380 Geom::Point prev = (star->flatsided? sp_star_get_xy (star, point, pi) : sp_star_get_xy (star, other, point == SP_STAR_POINT_KNOT2? index : pi));
381 Geom::Point next = (star->flatsided? sp_star_get_xy (star, point, ni) : sp_star_get_xy (star, other, point == SP_STAR_POINT_KNOT1? index : ni));
383 // prev-next midpoint
384 Geom::Point mid = 0.5 * (prev + next);
386 // point to which we direct the bissector of the curve handles;
387 // it's far enough outside the star on the perpendicular to prev-next through mid
388 Geom::Point biss = mid + 100000 * rot90_rel (mid, next);
390 // lengths of vectors to prev and next
391 gdouble prev_len = Geom::L2 (prev - o);
392 gdouble next_len = Geom::L2 (next - o);
394 // unit-length vector perpendicular to o-biss
395 Geom::Point rot = rot90_rel (o, biss);
397 // multiply rot by star->rounded coefficient and the distance to the star point; flip for next
398 Geom::Point ret;
399 if (previ) {
400 ret = (star->rounded * prev_len) * rot;
401 } else {
402 ret = (star->rounded * next_len * -1) * rot;
403 }
405 if (star->randomized == 0) {
406 // add the vector to o to get the final curvepoint
407 return o + ret;
408 } else {
409 // the seed corresponding to the exact point
410 guint32 seed = point_unique_int (o);
412 // randomly rotate (by step 3 from the seed) and scale (by step 4) the vector
413 ret = ret * Geom::Matrix (Geom::Rotate (star->randomized * M_PI * rnd (seed, 3)));
414 ret *= ( 1 + star->randomized * rnd (seed, 4));
416 // the randomized corner point
417 Geom::Point o_randomized = sp_star_get_xy (star, point, index, true);
419 return o_randomized + ret;
420 }
421 }
424 #define NEXT false
425 #define PREV true
427 static void
428 sp_star_set_shape (SPShape *shape)
429 {
430 SPStar *star = SP_STAR (shape);
432 // perhaps we should convert all our shapes into LPEs without source path
433 // and with knotholders for parameters, then this situation will be handled automatically
434 // by disabling the entire stack (including the shape LPE)
435 if (sp_lpe_item_has_broken_path_effect(SP_LPE_ITEM(shape))) {
436 g_warning ("The star shape has unknown LPE on it! Convert to path to make it editable preserving the appearance; editing it as star will remove the bad LPE");
437 if (SP_OBJECT_REPR(shape)->attribute("d")) {
438 // unconditionally read the curve from d, if any, to preserve appearance
439 Geom::PathVector pv = sp_svg_read_pathv(SP_OBJECT_REPR(shape)->attribute("d"));
440 SPCurve *cold = new SPCurve(pv);
441 shape->setCurveInsync( cold, TRUE);
442 cold->unref();
443 }
444 return;
445 }
447 SPCurve *c = new SPCurve ();
449 gint sides = star->sides;
450 bool not_rounded = (fabs (star->rounded) < 1e-4);
452 // note that we pass randomized=true to sp_star_get_xy, because the curve must be randomized;
453 // other places that call that function (e.g. the knotholder) need the exact point
455 // draw 1st segment
456 c->moveto(sp_star_get_xy (star, SP_STAR_POINT_KNOT1, 0, true));
457 if (star->flatsided == false) {
458 if (not_rounded) {
459 c->lineto(sp_star_get_xy (star, SP_STAR_POINT_KNOT2, 0, true));
460 } else {
461 c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, 0, NEXT),
462 sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, 0, PREV),
463 sp_star_get_xy (star, SP_STAR_POINT_KNOT2, 0, true));
464 }
465 }
467 // draw all middle segments
468 for (gint i = 1; i < sides; i++) {
469 if (not_rounded) {
470 c->lineto(sp_star_get_xy (star, SP_STAR_POINT_KNOT1, i, true));
471 } else {
472 if (star->flatsided == false) {
473 c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, i - 1, NEXT),
474 sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i, PREV),
475 sp_star_get_xy (star, SP_STAR_POINT_KNOT1, i, true));
476 } else {
477 c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i - 1, NEXT),
478 sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i, PREV),
479 sp_star_get_xy (star, SP_STAR_POINT_KNOT1, i, true));
480 }
481 }
482 if (star->flatsided == false) {
484 if (not_rounded) {
485 c->lineto(sp_star_get_xy (star, SP_STAR_POINT_KNOT2, i, true));
486 } else {
487 c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i, NEXT),
488 sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, i, PREV),
489 sp_star_get_xy (star, SP_STAR_POINT_KNOT2, i, true));
490 }
491 }
492 }
494 // draw last segment
495 if (!not_rounded) {
496 if (star->flatsided == false) {
497 c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, sides - 1, NEXT),
498 sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, 0, PREV),
499 sp_star_get_xy (star, SP_STAR_POINT_KNOT1, 0, true));
500 } else {
501 c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, sides - 1, NEXT),
502 sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, 0, PREV),
503 sp_star_get_xy (star, SP_STAR_POINT_KNOT1, 0, true));
504 }
505 }
507 c->closepath();
509 /* Reset the shape'scurve to the "original_curve"
510 * This is very important for LPEs to work properly! (the bbox might be recalculated depending on the curve in shape)*/
511 shape->setCurveInsync( c, TRUE);
512 if (sp_lpe_item_has_path_effect(SP_LPE_ITEM(shape)) && sp_lpe_item_path_effects_enabled(SP_LPE_ITEM(shape))) {
513 SPCurve *c_lpe = c->copy();
514 bool success = sp_lpe_item_perform_path_effect(SP_LPE_ITEM (shape), c_lpe);
515 if (success) {
516 shape->setCurveInsync( c_lpe, TRUE);
517 }
518 c_lpe->unref();
519 }
520 c->unref();
521 }
523 void
524 sp_star_position_set (SPStar *star, gint sides, Geom::Point center, gdouble r1, gdouble r2, gdouble arg1, gdouble arg2, bool isflat, double rounded, double randomized)
525 {
526 g_return_if_fail (star != NULL);
527 g_return_if_fail (SP_IS_STAR (star));
529 star->sides = NR_CLAMP(sides, 3, 1024);
530 star->center = center;
531 star->r[0] = MAX (r1, 0.001);
532 if (isflat == false) {
533 star->r[1] = NR_CLAMP(r2, 0.0, star->r[0]);
534 } else {
535 star->r[1] = NR_CLAMP( r1*cos(M_PI/sides) ,0.0, star->r[0] );
536 }
537 star->arg[0] = arg1;
538 star->arg[1] = arg2;
539 star->flatsided = isflat;
540 star->rounded = rounded;
541 star->randomized = randomized;
542 SP_OBJECT(star)->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
543 }
545 static void sp_star_snappoints(SPItem const *item, std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs)
546 {
547 // We will determine the star's midpoint ourselves, instead of trusting on the base class
548 // Therefore setSnapObjectMidpoints() is set to false temporarily
549 Inkscape::SnapPreferences local_snapprefs = *snapprefs;
550 local_snapprefs.setSnapObjectMidpoints(false);
552 if (((SPItemClass *) parent_class)->snappoints) {
553 ((SPItemClass *) parent_class)->snappoints (item, p, &local_snapprefs);
554 }
556 // Help enforcing strict snapping, i.e. only return nodes when we're snapping nodes to nodes or a guide to nodes
557 if (!(snapprefs->getSnapModeNode() || snapprefs->getSnapModeGuide())) {
558 return;
559 }
561 if (snapprefs->getSnapObjectMidpoints()) {
562 Geom::Matrix const i2d (item->i2d_affine ());
563 p.push_back(Inkscape::SnapCandidatePoint(SP_STAR(item)->center * i2d,Inkscape::SNAPSOURCE_OBJECT_MIDPOINT, Inkscape::SNAPTARGET_OBJECT_MIDPOINT));
564 }
565 }
567 /**
568 * sp_star_get_xy: Get X-Y value as item coordinate system
569 * @star: star item
570 * @point: point type to obtain X-Y value
571 * @index: index of vertex
572 * @p: pointer to store X-Y value
573 * @randomized: false (default) if you want to get exact, not randomized point
574 *
575 * Initial item coordinate system is same as document coordinate system.
576 */
578 Geom::Point
579 sp_star_get_xy (SPStar *star, SPStarPoint point, gint index, bool randomized)
580 {
581 gdouble darg = 2.0 * M_PI / (double) star->sides;
583 double arg = star->arg[point];
584 arg += index * darg;
586 Geom::Point xy = star->r[point] * Geom::Point(cos(arg), sin(arg)) + star->center;
588 if (!randomized || star->randomized == 0) {
589 // return the exact point
590 return xy;
591 } else { // randomize the point
592 // find out the seed, unique for this point so that randomization is the same so long as the original point is stationary
593 guint32 seed = point_unique_int (xy);
594 // the full range (corresponding to star->randomized == 1.0) is equal to the star's diameter
595 double range = 2 * MAX (star->r[0], star->r[1]);
596 // find out the random displacement; x is controlled by step 1 from the seed, y by the step 2
597 Geom::Point shift (star->randomized * range * rnd (seed, 1), star->randomized * range * rnd (seed, 2));
598 // add the shift to the exact point
599 return xy + shift;
600 }
601 }
603 /*
604 Local Variables:
605 mode:c++
606 c-file-style:"stroustrup"
607 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
608 indent-tabs-mode:nil
609 fill-column:99
610 End:
611 */
612 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :