1 /** @file
2 * Path manipulator - implementation
3 */
4 /* Authors:
5 * Krzysztof KosiĆski <tweenk.pl@gmail.com>
6 *
7 * Copyright (C) 2009 Authors
8 * Released under GNU GPL, read the file 'COPYING' for more information
9 */
11 #include <string>
12 #include <sstream>
13 #include <deque>
14 #include <stdexcept>
15 #include <boost/shared_ptr.hpp>
16 #include <2geom/bezier-curve.h>
17 #include <2geom/bezier-utils.h>
18 #include <2geom/svg-path.h>
19 #include <glibmm.h>
20 #include <glibmm/i18n.h>
21 #include "ui/tool/path-manipulator.h"
22 #include "desktop.h"
23 #include "desktop-handles.h"
24 #include "display/sp-canvas.h"
25 #include "display/sp-canvas-util.h"
26 #include "display/curve.h"
27 #include "display/canvas-bpath.h"
28 #include "document.h"
29 #include "live_effects/effect.h"
30 #include "live_effects/lpeobject.h"
31 #include "live_effects/parameter/path.h"
32 #include "sp-path.h"
33 #include "helper/geom.h"
34 #include "preferences.h"
35 #include "style.h"
36 #include "ui/tool/control-point-selection.h"
37 #include "ui/tool/curve-drag-point.h"
38 #include "ui/tool/event-utils.h"
39 #include "ui/tool/multi-path-manipulator.h"
40 #include "xml/node.h"
41 #include "xml/node-observer.h"
43 namespace Inkscape {
44 namespace UI {
46 namespace {
47 /// Types of path changes that we must react to.
48 enum PathChange {
49 PATH_CHANGE_D,
50 PATH_CHANGE_TRANSFORM
51 };
53 } // anonymous namespace
55 /**
56 * Notifies the path manipulator when something changes the path being edited
57 * (e.g. undo / redo)
58 */
59 class PathManipulatorObserver : public Inkscape::XML::NodeObserver {
60 public:
61 PathManipulatorObserver(PathManipulator *p) : _pm(p), _blocked(false) {}
62 virtual void notifyAttributeChanged(Inkscape::XML::Node &, GQuark attr,
63 Util::ptr_shared<char>, Util::ptr_shared<char>)
64 {
65 // do nothing if blocked
66 if (_blocked) return;
68 GQuark path_d = g_quark_from_static_string("d");
69 GQuark path_transform = g_quark_from_static_string("transform");
70 GQuark lpe_quark = _pm->_lpe_key.empty() ? 0 : g_quark_from_string(_pm->_lpe_key.data());
72 // only react to "d" (path data) and "transform" attribute changes
73 if (attr == lpe_quark || attr == path_d) {
74 _pm->_externalChange(PATH_CHANGE_D);
75 } else if (attr == path_transform) {
76 _pm->_externalChange(PATH_CHANGE_TRANSFORM);
77 }
78 }
79 void block() { _blocked = true; }
80 void unblock() { _blocked = false; }
81 private:
82 PathManipulator *_pm;
83 bool _blocked;
84 };
86 void build_segment(Geom::PathBuilder &, Node *, Node *);
88 PathManipulator::PathManipulator(MultiPathManipulator &mpm, SPPath *path,
89 Geom::Matrix const &et, guint32 outline_color, Glib::ustring lpe_key)
90 : PointManipulator(mpm._path_data.node_data.desktop, *mpm._path_data.node_data.selection)
91 , _subpaths(*this)
92 , _multi_path_manipulator(mpm)
93 , _path(path)
94 , _spcurve(NULL)
95 , _dragpoint(new CurveDragPoint(*this))
96 , _observer(new PathManipulatorObserver(this))
97 , _edit_transform(et)
98 , _num_selected(0)
99 , _show_handles(true)
100 , _show_outline(false)
101 , _lpe_key(lpe_key)
102 {
103 /* Because curve drag point is always created first, it does not cover nodes */
104 if (_lpe_key.empty()) {
105 _i2d_transform = sp_item_i2d_affine(SP_ITEM(path));
106 } else {
107 _i2d_transform = Geom::identity();
108 }
109 _d2i_transform = _i2d_transform.inverse();
110 _dragpoint->setVisible(false);
112 _getGeometry();
114 _outline = sp_canvas_bpath_new(_multi_path_manipulator._path_data.outline_group, NULL);
115 sp_canvas_item_hide(_outline);
116 sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(_outline), outline_color, 1.0,
117 SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
118 sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(_outline), 0, SP_WIND_RULE_NONZERO);
120 _subpaths.signal_insert_node.connect(
121 sigc::mem_fun(*this, &PathManipulator::_attachNodeHandlers));
122 _subpaths.signal_remove_node.connect(
123 sigc::mem_fun(*this, &PathManipulator::_removeNodeHandlers));
124 _selection.signal_update.connect(
125 sigc::mem_fun(*this, &PathManipulator::update));
126 _selection.signal_point_changed.connect(
127 sigc::mem_fun(*this, &PathManipulator::_selectionChanged));
128 _dragpoint->signal_update.connect(
129 sigc::mem_fun(*this, &PathManipulator::update));
130 _desktop->signal_zoom_changed.connect(
131 sigc::hide( sigc::mem_fun(*this, &PathManipulator::_updateOutlineOnZoomChange)));
133 _createControlPointsFromGeometry();
135 _path->repr->addObserver(*_observer);
136 }
138 PathManipulator::~PathManipulator()
139 {
140 delete _dragpoint;
141 if (_path) _path->repr->removeObserver(*_observer);
142 delete _observer;
143 gtk_object_destroy(_outline);
144 if (_spcurve) _spcurve->unref();
145 clear();
146 }
148 /** Handle motion events to update the position of the curve drag point. */
149 bool PathManipulator::event(GdkEvent *event)
150 {
151 if (empty()) return false;
153 switch (event->type)
154 {
155 case GDK_MOTION_NOTIFY:
156 _updateDragPoint(event_point(event->motion));
157 break;
158 default: break;
159 }
160 return false;
161 }
163 /** Check whether the manipulator has any nodes. */
164 bool PathManipulator::empty() {
165 return !_path || _subpaths.empty();
166 }
168 /** Update the display and the outline of the path. */
169 void PathManipulator::update()
170 {
171 _createGeometryFromControlPoints();
172 }
174 /** Store the changes to the path in XML. */
175 void PathManipulator::writeXML()
176 {
177 if (!_path) return;
178 _observer->block();
179 if (!empty()) {
180 SP_OBJECT(_path)->updateRepr();
181 _getXMLNode()->setAttribute(_nodetypesKey().data(), _createTypeString().data());
182 } else {
183 // this manipulator will have to be destroyed right after this call
184 _getXMLNode()->removeObserver(*_observer);
185 sp_object_ref(_path);
186 _path->deleteObject(true, true);
187 sp_object_unref(_path);
188 _path = 0;
189 }
190 _observer->unblock();
191 }
193 /** Remove all nodes from the path. */
194 void PathManipulator::clear()
195 {
196 // no longer necessary since nodes remove themselves from selection on destruction
197 //_removeNodesFromSelection();
198 _subpaths.clear();
199 }
201 /** Select all nodes in subpaths that have something selected. */
202 void PathManipulator::selectSubpaths()
203 {
204 for (std::list<SubpathPtr>::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
205 NodeList::iterator sp_start = (*i)->begin(), sp_end = (*i)->end();
206 for (NodeList::iterator j = sp_start; j != sp_end; ++j) {
207 if (j->selected()) {
208 // if at least one of the nodes from this subpath is selected,
209 // select all nodes from this subpath
210 for (NodeList::iterator ins = sp_start; ins != sp_end; ++ins)
211 _selection.insert(ins.ptr());
212 continue;
213 }
214 }
215 }
216 }
218 /** Move the selection forward or backward by one node in each subpath, based on the sign
219 * of the parameter. */
220 void PathManipulator::shiftSelection(int dir)
221 {
222 if (dir == 0) return;
223 if (_num_selected == 0) {
224 // select the first node of the path.
225 SubpathList::iterator s = _subpaths.begin();
226 if (s == _subpaths.end()) return;
227 NodeList::iterator n = (*s)->begin();
228 if (n != (*s)->end())
229 _selection.insert(n.ptr());
230 return;
231 }
232 // We cannot do any tricks here, like iterating in different directions based on
233 // the sign and only setting the selection of nodes behind us, because it would break
234 // for closed paths.
235 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
236 std::deque<bool> sels; // I hope this is specialized for bools!
237 unsigned num = 0;
239 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
240 sels.push_back(j->selected());
241 _selection.erase(j.ptr());
242 ++num;
243 }
244 if (num == 0) continue; // should never happen! zero-node subpaths are not allowed
246 num = 0;
247 // In closed subpath, shift the selection cyclically. In an open one,
248 // let the selection 'slide into nothing' at ends.
249 if (dir > 0) {
250 if ((*i)->closed()) {
251 bool last = sels.back();
252 sels.pop_back();
253 sels.push_front(last);
254 } else {
255 sels.push_front(false);
256 }
257 } else {
258 if ((*i)->closed()) {
259 bool first = sels.front();
260 sels.pop_front();
261 sels.push_back(first);
262 } else {
263 sels.push_back(false);
264 num = 1;
265 }
266 }
268 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
269 if (sels[num]) _selection.insert(j.ptr());
270 ++num;
271 }
272 }
273 }
275 /** Invert selection in the selected subpaths. */
276 void PathManipulator::invertSelectionInSubpaths()
277 {
278 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
279 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
280 if (j->selected()) {
281 // found selected node - invert selection in this subpath
282 for (NodeList::iterator k = (*i)->begin(); k != (*i)->end(); ++k) {
283 if (k->selected()) _selection.erase(k.ptr());
284 else _selection.insert(k.ptr());
285 }
286 // next subpath
287 break;
288 }
289 }
290 }
291 }
293 /** Insert a new node in the middle of each selected segment. */
294 void PathManipulator::insertNodes()
295 {
296 if (_num_selected < 2) return;
298 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
299 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
300 NodeList::iterator k = j.next();
301 if (k && j->selected() && k->selected()) {
302 j = subdivideSegment(j, 0.5);
303 _selection.insert(j.ptr());
304 }
305 }
306 }
307 }
309 /** Replace contiguous selections of nodes in each subpath with one node. */
310 void PathManipulator::weldNodes(NodeList::iterator preserve_pos)
311 {
312 if (_num_selected < 2) return;
313 hideDragPoint();
315 bool pos_valid = preserve_pos;
316 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
317 SubpathPtr sp = *i;
318 unsigned num_selected = 0, num_unselected = 0;
319 for (NodeList::iterator j = sp->begin(); j != sp->end(); ++j) {
320 if (j->selected()) ++num_selected;
321 else ++num_unselected;
322 }
323 if (num_selected < 2) continue;
324 if (num_unselected == 0) {
325 // if all nodes in a subpath are selected, the operation doesn't make much sense
326 continue;
327 }
329 // Start from unselected node in closed paths, so that we don't start in the middle
330 // of a selection
331 NodeList::iterator sel_beg = sp->begin(), sel_end;
332 if (sp->closed()) {
333 while (sel_beg->selected()) ++sel_beg;
334 }
336 // Work loop
337 while (num_selected > 0) {
338 // Find selected node
339 while (sel_beg && !sel_beg->selected()) sel_beg = sel_beg.next();
340 if (!sel_beg) throw std::logic_error("Join nodes: end of open path reached, "
341 "but there are still nodes to process!");
343 // note: this is initialized to zero, because the loop below counts sel_beg as well
344 // the loop conditions are simpler that way
345 unsigned num_points = 0;
346 bool use_pos = false;
347 Geom::Point back_pos, front_pos;
348 back_pos = *sel_beg->back();
350 for (sel_end = sel_beg; sel_end && sel_end->selected(); sel_end = sel_end.next()) {
351 ++num_points;
352 front_pos = *sel_end->front();
353 if (pos_valid && sel_end == preserve_pos) use_pos = true;
354 }
355 if (num_points > 1) {
356 Geom::Point joined_pos;
357 if (use_pos) {
358 joined_pos = preserve_pos->position();
359 pos_valid = false;
360 } else {
361 joined_pos = Geom::middle_point(back_pos, front_pos);
362 }
363 sel_beg->setType(NODE_CUSP, false);
364 sel_beg->move(joined_pos);
365 // do not move handles if they aren't degenerate
366 if (!sel_beg->back()->isDegenerate()) {
367 sel_beg->back()->setPosition(back_pos);
368 }
369 if (!sel_end.prev()->front()->isDegenerate()) {
370 sel_beg->front()->setPosition(front_pos);
371 }
372 sel_beg = sel_beg.next();
373 while (sel_beg != sel_end) {
374 NodeList::iterator next = sel_beg.next();
375 sp->erase(sel_beg);
376 sel_beg = next;
377 --num_selected;
378 }
379 }
380 --num_selected; // for the joined node or single selected node
381 }
382 }
383 }
385 /** Remove nodes in the middle of selected segments. */
386 void PathManipulator::weldSegments()
387 {
388 if (_num_selected < 2) return;
389 hideDragPoint();
391 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
392 SubpathPtr sp = *i;
393 unsigned num_selected = 0, num_unselected = 0;
394 for (NodeList::iterator j = sp->begin(); j != sp->end(); ++j) {
395 if (j->selected()) ++num_selected;
396 else ++num_unselected;
397 }
398 if (num_selected < 3) continue;
399 if (num_unselected == 0 && sp->closed()) {
400 // if all nodes in a closed subpath are selected, the operation doesn't make much sense
401 continue;
402 }
404 // Start from unselected node in closed paths, so that we don't start in the middle
405 // of a selection
406 NodeList::iterator sel_beg = sp->begin(), sel_end;
407 if (sp->closed()) {
408 while (sel_beg->selected()) ++sel_beg;
409 }
411 // Work loop
412 while (num_selected > 0) {
413 // Find selected node
414 while (sel_beg && !sel_beg->selected()) sel_beg = sel_beg.next();
415 if (!sel_beg) throw std::logic_error("Join nodes: end of open path reached, "
416 "but there are still nodes to process!");
418 // note: this is initialized to zero, because the loop below counts sel_beg as well
419 // the loop conditions are simpler that way
420 unsigned num_points = 0;
422 // find the end of selected segment
423 for (sel_end = sel_beg; sel_end && sel_end->selected(); sel_end = sel_end.next()) {
424 ++num_points;
425 }
426 if (num_points > 2) {
427 // remove nodes in the middle
428 sel_beg = sel_beg.next();
429 while (sel_beg != sel_end.prev()) {
430 NodeList::iterator next = sel_beg.next();
431 sp->erase(sel_beg);
432 sel_beg = next;
433 }
434 sel_beg = sel_end;
435 }
436 num_selected -= num_points;
437 }
438 }
439 }
441 /** Break the subpath at selected nodes. It also works for single node closed paths. */
442 void PathManipulator::breakNodes()
443 {
444 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
445 SubpathPtr sp = *i;
446 NodeList::iterator cur = sp->begin(), end = sp->end();
447 if (!sp->closed()) {
448 // Each open path must have at least two nodes so no checks are required.
449 // For 2-node open paths, cur == end
450 ++cur;
451 --end;
452 }
453 for (; cur != end; ++cur) {
454 if (!cur->selected()) continue;
455 SubpathPtr ins;
456 bool becomes_open = false;
458 if (sp->closed()) {
459 // Move the node to break at to the beginning of path
460 if (cur != sp->begin())
461 sp->splice(sp->begin(), *sp, cur, sp->end());
462 sp->setClosed(false);
463 ins = sp;
464 becomes_open = true;
465 } else {
466 SubpathPtr new_sp(new NodeList(_subpaths));
467 new_sp->splice(new_sp->end(), *sp, sp->begin(), cur);
468 _subpaths.insert(i, new_sp);
469 ins = new_sp;
470 }
472 Node *n = new Node(_multi_path_manipulator._path_data.node_data, cur->position());
473 ins->insert(ins->end(), n);
474 cur->setType(NODE_CUSP, false);
475 n->back()->setRelativePos(cur->back()->relativePos());
476 cur->back()->retract();
477 n->sink();
479 if (becomes_open) {
480 cur = sp->begin(); // this will be increased to ++sp->begin()
481 end = --sp->end();
482 }
483 }
484 }
485 }
487 /** Delete selected nodes in the path, optionally substituting deleted segments with bezier curves
488 * in a way that attempts to preserve the original shape of the curve. */
489 void PathManipulator::deleteNodes(bool keep_shape)
490 {
491 if (_num_selected == 0) return;
492 hideDragPoint();
494 unsigned const samples_per_segment = 10;
495 double const t_step = 1.0 / samples_per_segment;
497 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end();) {
498 SubpathPtr sp = *i;
500 // If there are less than 2 unselected nodes in an open subpath or no unselected nodes
501 // in a closed one, delete entire subpath.
502 unsigned num_unselected = 0, num_selected = 0;
503 for (NodeList::iterator j = sp->begin(); j != sp->end(); ++j) {
504 if (j->selected()) ++num_selected;
505 else ++num_unselected;
506 }
507 if (num_selected == 0) {
508 ++i;
509 continue;
510 }
511 if (sp->closed() ? (num_unselected < 1) : (num_unselected < 2)) {
512 _subpaths.erase(i++);
513 continue;
514 }
516 // In closed paths, start from an unselected node - otherwise we might start in the middle
517 // of a selected stretch and the resulting bezier fit would be suboptimal
518 NodeList::iterator sel_beg = sp->begin(), sel_end;
519 if (sp->closed()) {
520 while (sel_beg->selected()) ++sel_beg;
521 }
522 sel_end = sel_beg;
524 while (num_selected > 0) {
525 while (!sel_beg->selected()) sel_beg = sel_beg.next();
526 sel_end = sel_beg;
527 unsigned del_len = 0;
528 while (sel_end && sel_end->selected()) {
529 ++del_len;
530 sel_end = sel_end.next();
531 }
533 // set surrounding node types to cusp if:
534 // 1. keep_shape is on, or
535 // 2. we are deleting at the end or beginning of an open path
536 // if !sel_end then sel_beg.prev() must be valid, otherwise the entire subpath
537 // would be deleted before we get here
538 if ((keep_shape || !sel_end) && sel_beg.prev()) sel_beg.prev()->setType(NODE_CUSP, false);
539 if ((keep_shape || !sel_beg.prev()) && sel_end) sel_end->setType(NODE_CUSP, false);
541 if (keep_shape && sel_beg.prev() && sel_end) {
542 // Fill fit data
543 unsigned num_samples = (del_len + 1) * samples_per_segment + 1;
544 Geom::Point *bezier_data = new Geom::Point[num_samples];
545 Geom::Point result[4];
546 unsigned seg = 0;
548 for (NodeList::iterator cur = sel_beg.prev(); cur != sel_end; cur = cur.next()) {
549 Geom::CubicBezier bc(*cur, *cur->front(), *cur.next(), *cur.next()->back());
550 for (unsigned s = 0; s < samples_per_segment; ++s) {
551 bezier_data[seg * samples_per_segment + s] = bc.pointAt(t_step * s);
552 }
553 ++seg;
554 }
555 // Fill last point
556 bezier_data[num_samples - 1] = sel_end->position();
557 // Compute replacement bezier curve
558 // TODO the fitting algorithm sucks - rewrite it to be awesome
559 bezier_fit_cubic(result, bezier_data, num_samples, 0.5);
560 delete[] bezier_data;
562 sel_beg.prev()->front()->setPosition(result[1]);
563 sel_end->back()->setPosition(result[2]);
564 }
565 // We cannot simply use sp->erase(sel_beg, sel_end), because it would break
566 // for cases when the selected stretch crosses the beginning of the path
567 while (sel_beg != sel_end) {
568 NodeList::iterator next = sel_beg.next();
569 sp->erase(sel_beg);
570 sel_beg = next;
571 }
572 num_selected -= del_len;
573 }
574 ++i;
575 }
576 }
578 /** Removes selected segments */
579 void PathManipulator::deleteSegments()
580 {
581 if (_num_selected == 0) return;
582 hideDragPoint();
584 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end();) {
585 SubpathPtr sp = *i;
586 bool has_unselected = false;
587 unsigned num_selected = 0;
588 for (NodeList::iterator j = sp->begin(); j != sp->end(); ++j) {
589 if (j->selected()) {
590 ++num_selected;
591 } else {
592 has_unselected = true;
593 }
594 }
595 if (!has_unselected) {
596 _subpaths.erase(i++);
597 continue;
598 }
600 NodeList::iterator sel_beg = sp->begin();
601 if (sp->closed()) {
602 while (sel_beg && sel_beg->selected()) ++sel_beg;
603 }
604 while (num_selected > 0) {
605 if (!sel_beg->selected()) {
606 sel_beg = sel_beg.next();
607 continue;
608 }
609 NodeList::iterator sel_end = sel_beg;
610 unsigned num_points = 0;
611 while (sel_end && sel_end->selected()) {
612 sel_end = sel_end.next();
613 ++num_points;
614 }
615 if (num_points >= 2) {
616 // Retract end handles
617 sel_end.prev()->setType(NODE_CUSP, false);
618 sel_end.prev()->back()->retract();
619 sel_beg->setType(NODE_CUSP, false);
620 sel_beg->front()->retract();
621 if (sp->closed()) {
622 // In closed paths, relocate the beginning of the path to the last selected
623 // node and then unclose it. Remove the nodes from the first selected node
624 // to the new end of path.
625 if (sel_end.prev() != sp->begin())
626 sp->splice(sp->begin(), *sp, sel_end.prev(), sp->end());
627 sp->setClosed(false);
628 sp->erase(sel_beg.next(), sp->end());
629 } else {
630 // for open paths:
631 // 1. At end or beginning, delete including the node on the end or beginning
632 // 2. In the middle, delete only inner nodes
633 if (sel_beg == sp->begin()) {
634 sp->erase(sp->begin(), sel_end.prev());
635 } else if (sel_end == sp->end()) {
636 sp->erase(sel_beg.next(), sp->end());
637 } else {
638 SubpathPtr new_sp(new NodeList(_subpaths));
639 new_sp->splice(new_sp->end(), *sp, sp->begin(), sel_beg.next());
640 _subpaths.insert(i, new_sp);
641 if (sel_end.prev())
642 sp->erase(sp->begin(), sel_end.prev());
643 }
644 }
645 }
646 sel_beg = sel_end;
647 num_selected -= num_points;
648 }
649 ++i;
650 }
651 }
653 /** Reverse the subpaths that have anything selected. */
654 void PathManipulator::reverseSubpaths()
655 {
656 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
657 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
658 if (j->selected()) {
659 (*i)->reverse();
660 break; // continue with the next subpath
661 }
662 }
663 }
664 }
666 /** Make selected segments curves / lines. */
667 void PathManipulator::setSegmentType(SegmentType type)
668 {
669 if (_num_selected == 0) return;
670 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
671 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
672 NodeList::iterator k = j.next();
673 if (!(k && j->selected() && k->selected())) continue;
674 switch (type) {
675 case SEGMENT_STRAIGHT:
676 if (j->front()->isDegenerate() && k->back()->isDegenerate())
677 break;
678 j->front()->move(*j);
679 k->back()->move(*k);
680 break;
681 case SEGMENT_CUBIC_BEZIER:
682 if (!j->front()->isDegenerate() || !k->back()->isDegenerate())
683 break;
684 j->front()->move(j->position() + (k->position() - j->position()) / 3);
685 k->back()->move(k->position() + (j->position() - k->position()) / 3);
686 break;
687 }
688 }
689 }
690 }
692 /** Set the visibility of handles. */
693 void PathManipulator::showHandles(bool show)
694 {
695 if (show == _show_handles) return;
696 if (show) {
697 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
698 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
699 if (!j->selected()) continue;
700 j->showHandles(true);
701 if (j.prev()) j.prev()->showHandles(true);
702 if (j.next()) j.next()->showHandles(true);
703 }
704 }
705 } else {
706 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
707 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
708 j->showHandles(false);
709 }
710 }
711 }
712 _show_handles = show;
713 }
715 /** Set the visibility of outline. */
716 void PathManipulator::showOutline(bool show)
717 {
718 if (show == _show_outline) return;
719 _show_outline = show;
720 _updateOutline();
721 }
723 void PathManipulator::showPathDirection(bool show)
724 {
725 if (show == _show_path_direction) return;
726 _show_path_direction = show;
727 _updateOutline();
728 }
730 void PathManipulator::setControlsTransform(Geom::Matrix const &tnew)
731 {
732 Geom::Matrix delta = _i2d_transform.inverse() * _edit_transform.inverse() * tnew * _i2d_transform;
733 _edit_transform = tnew;
734 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
735 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
736 j->transform(delta);
737 }
738 }
739 _createGeometryFromControlPoints();
740 }
742 /** Hide the curve drag point until the next motion event.
743 * This should be called at the beginning of every method that can delete nodes.
744 * Otherwise the invalidated iterator in the dragpoint can cause crashes. */
745 void PathManipulator::hideDragPoint()
746 {
747 _dragpoint->setVisible(false);
748 _dragpoint->setIterator(NodeList::iterator());
749 }
751 /** Insert a node in the segment beginning with the supplied iterator,
752 * at the given time value */
753 NodeList::iterator PathManipulator::subdivideSegment(NodeList::iterator first, double t)
754 {
755 if (!first) throw std::invalid_argument("Subdivide after invalid iterator");
756 NodeList &list = NodeList::get(first);
757 NodeList::iterator second = first.next();
758 if (!second) throw std::invalid_argument("Subdivide after last node in open path");
760 // We need to insert the segment after 'first'. We can't simply use 'second'
761 // as the point of insertion, because when 'first' is the last node of closed path,
762 // the new node will be inserted as the first node instead.
763 NodeList::iterator insert_at = first;
764 ++insert_at;
766 NodeList::iterator inserted;
767 if (first->front()->isDegenerate() && second->back()->isDegenerate()) {
768 // for a line segment, insert a cusp node
769 Node *n = new Node(_multi_path_manipulator._path_data.node_data,
770 Geom::lerp(t, first->position(), second->position()));
771 n->setType(NODE_CUSP, false);
772 inserted = list.insert(insert_at, n);
773 } else {
774 // build bezier curve and subdivide
775 Geom::CubicBezier temp(first->position(), first->front()->position(),
776 second->back()->position(), second->position());
777 std::pair<Geom::CubicBezier, Geom::CubicBezier> div = temp.subdivide(t);
778 std::vector<Geom::Point> seg1 = div.first.points(), seg2 = div.second.points();
780 // set new handle positions
781 Node *n = new Node(_multi_path_manipulator._path_data.node_data, seg2[0]);
782 n->back()->setPosition(seg1[2]);
783 n->front()->setPosition(seg2[1]);
784 n->setType(NODE_SMOOTH, false);
785 inserted = list.insert(insert_at, n);
787 first->front()->move(seg1[1]);
788 second->back()->move(seg2[2]);
789 }
790 return inserted;
791 }
793 /** Find the node that is closest/farthest from the origin
794 * @param origin Point of reference
795 * @param search_selected Consider selected nodes
796 * @param search_unselected Consider unselected nodes
797 * @param closest If true, return closest node, if false, return farthest
798 * @return The matching node, or an empty iterator if none found
799 */
800 NodeList::iterator PathManipulator::extremeNode(NodeList::iterator origin, bool search_selected,
801 bool search_unselected, bool closest)
802 {
803 NodeList::iterator match;
804 double extr_dist = closest ? HUGE_VAL : -HUGE_VAL;
805 if (_num_selected == 0 && !search_unselected) return match;
807 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
808 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
809 if(j->selected()) {
810 if (!search_selected) continue;
811 } else {
812 if (!search_unselected) continue;
813 }
814 double dist = Geom::distance(*j, *origin);
815 bool cond = closest ? (dist < extr_dist) : (dist > extr_dist);
816 if (cond) {
817 match = j;
818 extr_dist = dist;
819 }
820 }
821 }
822 return match;
823 }
825 /** Called by the XML observer when something else than us modifies the path. */
826 void PathManipulator::_externalChange(unsigned type)
827 {
828 switch (type) {
829 case PATH_CHANGE_D: {
830 _getGeometry();
832 // ugly: stored offsets of selected nodes in a vector
833 // vector<bool> should be specialized so that it takes only 1 bit per value
834 std::vector<bool> selpos;
835 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
836 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
837 selpos.push_back(j->selected());
838 }
839 }
840 unsigned size = selpos.size(), curpos = 0;
842 _createControlPointsFromGeometry();
844 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
845 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
846 if (curpos >= size) goto end_restore;
847 if (selpos[curpos]) _selection.insert(j.ptr());
848 ++curpos;
849 }
850 }
851 end_restore:
853 _updateOutline();
854 } break;
855 case PATH_CHANGE_TRANSFORM: {
856 Geom::Matrix i2d_change = _d2i_transform;
857 _i2d_transform = sp_item_i2d_affine(SP_ITEM(_path));
858 _d2i_transform = _i2d_transform.inverse();
859 i2d_change *= _i2d_transform;
860 for (SubpathList::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
861 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
862 j->transform(i2d_change);
863 }
864 }
865 _updateOutline();
866 } break;
867 default: break;
868 }
869 }
871 /** Create nodes and handles based on the XML of the edited path. */
872 void PathManipulator::_createControlPointsFromGeometry()
873 {
874 clear();
876 // sanitize pathvector and store it in SPCurve,
877 // so that _updateDragPoint doesn't crash on paths with naked movetos
878 Geom::PathVector pathv = pathv_to_linear_and_cubic_beziers(_spcurve->get_pathvector());
879 for (Geom::PathVector::iterator i = pathv.begin(); i != pathv.end(); ) {
880 if (i->empty()) pathv.erase(i++);
881 else ++i;
882 }
883 _spcurve->set_pathvector(pathv);
885 pathv *= (_edit_transform * _i2d_transform);
887 // in this loop, we know that there are no zero-segment subpaths
888 for (Geom::PathVector::const_iterator pit = pathv.begin(); pit != pathv.end(); ++pit) {
889 // prepare new subpath
890 SubpathPtr subpath(new NodeList(_subpaths));
891 _subpaths.push_back(subpath);
893 Node *previous_node = new Node(_multi_path_manipulator._path_data.node_data, pit->initialPoint());
894 subpath->push_back(previous_node);
895 Geom::Curve const &cseg = pit->back_closed();
896 bool fuse_ends = pit->closed()
897 && Geom::are_near(cseg.initialPoint(), cseg.finalPoint());
899 for (Geom::Path::const_iterator cit = pit->begin(); cit != pit->end_open(); ++cit) {
900 Geom::Point pos = cit->finalPoint();
901 Node *current_node;
902 // if the closing segment is degenerate and the path is closed, we need to move
903 // the handle of the first node instead of creating a new one
904 if (fuse_ends && cit == --(pit->end_open())) {
905 current_node = subpath->begin().get_pointer();
906 } else {
907 /* regardless of segment type, create a new node at the end
908 * of this segment (unless this is the last segment of a closed path
909 * with a degenerate closing segment */
910 current_node = new Node(_multi_path_manipulator._path_data.node_data, pos);
911 subpath->push_back(current_node);
912 }
913 // if this is a bezier segment, move handles appropriately
914 if (Geom::CubicBezier const *cubic_bezier =
915 dynamic_cast<Geom::CubicBezier const*>(&*cit))
916 {
917 std::vector<Geom::Point> points = cubic_bezier->points();
919 previous_node->front()->setPosition(points[1]);
920 current_node ->back() ->setPosition(points[2]);
921 }
922 previous_node = current_node;
923 }
924 // If the path is closed, make the list cyclic
925 if (pit->closed()) subpath->setClosed(true);
926 }
928 // we need to set the nodetypes after all the handles are in place,
929 // so that pickBestType works correctly
930 // TODO maybe migrate to inkscape:node-types?
931 gchar const *nts_raw = _path ? _path->repr->attribute(_nodetypesKey().data()) : 0;
932 std::string nodetype_string = nts_raw ? nts_raw : "";
933 /* Calculate the needed length of the nodetype string.
934 * For closed paths, the entry is duplicated for the starting node,
935 * so we can just use the count of segments including the closing one
936 * to include the extra end node. */
937 std::string::size_type nodetype_len = 0;
938 for (Geom::PathVector::const_iterator i = pathv.begin(); i != pathv.end(); ++i) {
939 if (i->empty()) continue;
940 nodetype_len += i->size_closed();
941 }
942 /* pad the string to required length with a bogus value.
943 * 'b' and any other letter not recognized by the parser causes the best fit to be set
944 * as the node type */
945 if (nodetype_len > nodetype_string.size()) {
946 nodetype_string.append(nodetype_len - nodetype_string.size(), 'b');
947 }
948 std::string::iterator tsi = nodetype_string.begin();
949 for (std::list<SubpathPtr>::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
950 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
951 j->setType(Node::parse_nodetype(*tsi++), false);
952 }
953 if ((*i)->closed()) {
954 // STUPIDITY ALERT: it seems we need to use the duplicate type symbol instead of
955 // the first one to remain backward compatible.
956 (*i)->begin()->setType(Node::parse_nodetype(*tsi++), false);
957 }
958 }
959 }
961 /** Construct the geometric representation of nodes and handles, update the outline
962 * and display */
963 void PathManipulator::_createGeometryFromControlPoints()
964 {
965 Geom::PathBuilder builder;
966 for (std::list<SubpathPtr>::iterator spi = _subpaths.begin(); spi != _subpaths.end(); ) {
967 SubpathPtr subpath = *spi;
968 if (subpath->empty()) {
969 _subpaths.erase(spi++);
970 continue;
971 }
972 NodeList::iterator prev = subpath->begin();
973 builder.moveTo(prev->position());
975 for (NodeList::iterator i = ++subpath->begin(); i != subpath->end(); ++i) {
976 build_segment(builder, prev.ptr(), i.ptr());
977 prev = i;
978 }
979 if (subpath->closed()) {
980 // Here we link the last and first node if the path is closed.
981 // If the last segment is Bezier, we add it.
982 if (!prev->front()->isDegenerate() || !subpath->begin()->back()->isDegenerate()) {
983 build_segment(builder, prev.ptr(), subpath->begin().ptr());
984 }
985 // if that segment is linear, we just call closePath().
986 builder.closePath();
987 }
988 ++spi;
989 }
990 builder.finish();
991 _spcurve->set_pathvector(builder.peek() * (_edit_transform * _i2d_transform).inverse());
992 _updateOutline();
993 _setGeometry();
994 }
996 /** Build one segment of the geometric representation.
997 * @relates PathManipulator */
998 void build_segment(Geom::PathBuilder &builder, Node *prev_node, Node *cur_node)
999 {
1000 if (cur_node->back()->isDegenerate() && prev_node->front()->isDegenerate())
1001 {
1002 // NOTE: It seems like the renderer cannot correctly handle vline / hline segments,
1003 // and trying to display a path using them results in funny artifacts.
1004 builder.lineTo(cur_node->position());
1005 } else {
1006 // this is a bezier segment
1007 builder.curveTo(
1008 prev_node->front()->position(),
1009 cur_node->back()->position(),
1010 cur_node->position());
1011 }
1012 }
1014 /** Construct a node type string to store in the sodipodi:nodetypes attribute. */
1015 std::string PathManipulator::_createTypeString()
1016 {
1017 // precondition: no single-node subpaths
1018 std::stringstream tstr;
1019 for (std::list<SubpathPtr>::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
1020 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
1021 tstr << j->type();
1022 }
1023 // nodestring format peculiarity: first node is counted twice for closed paths
1024 if ((*i)->closed()) tstr << (*i)->begin()->type();
1025 }
1026 return tstr.str();
1027 }
1029 /** Update the path outline. */
1030 void PathManipulator::_updateOutline()
1031 {
1032 if (!_show_outline) {
1033 sp_canvas_item_hide(_outline);
1034 return;
1035 }
1037 Geom::PathVector pv = _spcurve->get_pathvector();
1038 pv *= (_edit_transform * _i2d_transform);
1039 // This SPCurve thing has to be killed with extreme prejudice
1040 SPCurve *_hc = new SPCurve();
1041 if (_show_path_direction) {
1042 // To show the direction, we append additional subpaths which consist of a single
1043 // linear segment that starts at the time value of 0.5 and extends for 10 pixels
1044 // at an angle 150 degrees from the unit tangent. This creates the appearance
1045 // of little 'harpoons' that show the direction of the subpaths.
1046 Geom::PathVector arrows;
1047 for (Geom::PathVector::iterator i = pv.begin(); i != pv.end(); ++i) {
1048 Geom::Path &path = *i;
1049 for (Geom::Path::const_iterator j = path.begin(); j != path.end_default(); ++j) {
1050 Geom::Point at = j->pointAt(0.5);
1051 Geom::Point ut = j->unitTangentAt(0.5);
1052 // rotate the point
1053 ut *= Geom::Rotate(150.0 / 180.0 * M_PI);
1054 Geom::Point arrow_end = _desktop->w2d(
1055 _desktop->d2w(at) + Geom::unit_vector(_desktop->d2w(ut)) * 10.0);
1057 Geom::Path arrow(at);
1058 arrow.appendNew<Geom::LineSegment>(arrow_end);
1059 arrows.push_back(arrow);
1060 }
1061 }
1062 pv.insert(pv.end(), arrows.begin(), arrows.end());
1063 }
1064 _hc->set_pathvector(pv);
1065 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(_outline), _hc);
1066 sp_canvas_item_show(_outline);
1067 _hc->unref();
1068 }
1070 /** Retrieve the geometry of the edited object from the object tree */
1071 void PathManipulator::_getGeometry()
1072 {
1073 using namespace Inkscape::LivePathEffect;
1074 if (!_lpe_key.empty()) {
1075 Effect *lpe = LIVEPATHEFFECT(_path)->get_lpe();
1076 if (lpe) {
1077 PathParam *pathparam = dynamic_cast<PathParam *>(lpe->getParameter(_lpe_key.data()));
1078 if (!_spcurve)
1079 _spcurve = new SPCurve(pathparam->get_pathvector());
1080 else
1081 _spcurve->set_pathvector(pathparam->get_pathvector());
1082 }
1083 } else {
1084 if (_spcurve) _spcurve->unref();
1085 _spcurve = sp_path_get_curve_for_edit(_path);
1086 }
1087 }
1089 /** Set the geometry of the edited object in the object tree, but do not commit to XML */
1090 void PathManipulator::_setGeometry()
1091 {
1092 using namespace Inkscape::LivePathEffect;
1093 if (empty()) return;
1095 if (!_lpe_key.empty()) {
1096 // copied from nodepath.cpp
1097 // NOTE: if we are editing an LPE param, _path is not actually an SPPath, it is
1098 // a LivePathEffectObject. (mad laughter)
1099 Effect *lpe = LIVEPATHEFFECT(_path)->get_lpe();
1100 if (lpe) {
1101 PathParam *pathparam = dynamic_cast<PathParam *>(lpe->getParameter(_lpe_key.data()));
1102 pathparam->set_new_value(_spcurve->get_pathvector(), false);
1103 LIVEPATHEFFECT(_path)->requestModified(SP_OBJECT_MODIFIED_FLAG);
1104 }
1105 } else {
1106 if (_path->repr->attribute("inkscape:original-d"))
1107 sp_path_set_original_curve(_path, _spcurve, true, false);
1108 else
1109 sp_shape_set_curve(SP_SHAPE(_path), _spcurve, false);
1110 }
1111 }
1113 /** Figure out in what attribute to store the nodetype string. */
1114 Glib::ustring PathManipulator::_nodetypesKey()
1115 {
1116 if (_lpe_key.empty()) return "sodipodi:nodetypes";
1117 return _lpe_key + "-nodetypes";
1118 }
1120 /** Return the XML node we are editing.
1121 * This method is wrong but necessary at the moment. */
1122 Inkscape::XML::Node *PathManipulator::_getXMLNode()
1123 {
1124 if (_lpe_key.empty()) return _path->repr;
1125 return LIVEPATHEFFECT(_path)->repr;
1126 }
1128 void PathManipulator::_attachNodeHandlers(Node *node)
1129 {
1130 Handle *handles[2] = { node->front(), node->back() };
1131 for (int i = 0; i < 2; ++i) {
1132 handles[i]->signal_update.connect(
1133 sigc::mem_fun(*this, &PathManipulator::update));
1134 handles[i]->signal_ungrabbed.connect(
1135 sigc::hide(
1136 sigc::mem_fun(*this, &PathManipulator::_handleUngrabbed)));
1137 handles[i]->signal_grabbed.connect(
1138 sigc::bind_return(
1139 sigc::hide(
1140 sigc::mem_fun(*this, &PathManipulator::_handleGrabbed)),
1141 false));
1142 handles[i]->signal_clicked.connect(
1143 sigc::bind<0>(
1144 sigc::mem_fun(*this, &PathManipulator::_handleClicked),
1145 handles[i]));
1146 }
1147 node->signal_clicked.connect(
1148 sigc::bind<0>(
1149 sigc::mem_fun(*this, &PathManipulator::_nodeClicked),
1150 node));
1151 }
1152 void PathManipulator::_removeNodeHandlers(Node *node)
1153 {
1154 // It is safe to assume that nobody else connected to handles' signals after us,
1155 // so we pop our slots from the back. This preserves existing connections
1156 // created by Node and Handle constructors.
1157 Handle *handles[2] = { node->front(), node->back() };
1158 for (int i = 0; i < 2; ++i) {
1159 handles[i]->signal_update.slots().pop_back();
1160 handles[i]->signal_grabbed.slots().pop_back();
1161 handles[i]->signal_ungrabbed.slots().pop_back();
1162 handles[i]->signal_clicked.slots().pop_back();
1163 }
1164 // Same for this one: CPS only connects to grab, drag, and ungrab
1165 node->signal_clicked.slots().pop_back();
1166 }
1168 bool PathManipulator::_nodeClicked(Node *n, GdkEventButton *event)
1169 {
1170 // cycle between node types on ctrl+click
1171 if (event->button != 1 || !held_control(*event)) return false;
1172 /*if (held_alt(*event)) {
1173 // TODO delete nodes with Ctrl+Alt+click
1174 n->list()->erase(NodeList::get_iterator(n));
1175 update();
1176 _commit(_("Delete node"));
1177 } else*/ {
1178 if (n->isEndNode()) {
1179 if (n->type() == NODE_CUSP) {
1180 n->setType(NODE_SMOOTH);
1181 } else {
1182 n->setType(NODE_CUSP);
1183 }
1184 } else {
1185 n->setType(static_cast<NodeType>((n->type() + 1) % NODE_LAST_REAL_TYPE));
1186 }
1187 update();
1188 _commit(_("Cycle node type"));
1189 }
1190 return true;
1191 }
1193 void PathManipulator::_handleGrabbed()
1194 {
1195 _selection.hideTransformHandles();
1196 }
1198 void PathManipulator::_handleUngrabbed()
1199 {
1200 _selection.restoreTransformHandles();
1201 _commit(_("Drag handle"));
1202 }
1204 bool PathManipulator::_handleClicked(Handle *h, GdkEventButton *event)
1205 {
1206 // retracting by Ctrl+click
1207 if (event->button == 1 && held_control(*event)) {
1208 h->move(h->parent()->position());
1209 update();
1210 _commit(_("Retract handle"));
1211 return true;
1212 }
1213 return false;
1214 }
1216 void PathManipulator::_selectionChanged(SelectableControlPoint *p, bool selected)
1217 {
1218 // don't do anything if we do not show handles
1219 if (!_show_handles) return;
1221 // only do something if a node changed selection state
1222 Node *node = dynamic_cast<Node*>(p);
1223 if (!node) return;
1225 // update handle display
1226 NodeList::iterator iters[5];
1227 iters[2] = NodeList::get_iterator(node);
1228 iters[1] = iters[2].prev();
1229 iters[3] = iters[2].next();
1230 if (selected) {
1231 // selection - show handles on this node and adjacent ones
1232 node->showHandles(true);
1233 if (iters[1]) iters[1]->showHandles(true);
1234 if (iters[3]) iters[3]->showHandles(true);
1235 } else {
1236 /* Deselection is more complex.
1237 * The change might affect 3 nodes - this one and two adjacent.
1238 * If the node and both its neighbors are deselected, hide handles.
1239 * Otherwise, leave as is. */
1240 if (iters[1]) iters[0] = iters[1].prev();
1241 if (iters[3]) iters[4] = iters[3].next();
1242 bool nodesel[5];
1243 for (int i = 0; i < 5; ++i) {
1244 nodesel[i] = iters[i] && iters[i]->selected();
1245 }
1246 for (int i = 1; i < 4; ++i) {
1247 if (iters[i] && !nodesel[i-1] && !nodesel[i] && !nodesel[i+1]) {
1248 iters[i]->showHandles(false);
1249 }
1250 }
1251 }
1253 if (selected) ++_num_selected;
1254 else --_num_selected;
1255 }
1257 /** Removes all nodes belonging to this manipulator from the control pont selection */
1258 void PathManipulator::_removeNodesFromSelection()
1259 {
1260 // remove this manipulator's nodes from selection
1261 for (std::list<SubpathPtr>::iterator i = _subpaths.begin(); i != _subpaths.end(); ++i) {
1262 for (NodeList::iterator j = (*i)->begin(); j != (*i)->end(); ++j) {
1263 _selection.erase(j.get_pointer());
1264 }
1265 }
1266 }
1268 /** Update the XML representation and put the specified annotation on the undo stack */
1269 void PathManipulator::_commit(Glib::ustring const &annotation)
1270 {
1271 writeXML();
1272 sp_document_done(sp_desktop_document(_desktop), SP_VERB_CONTEXT_NODE, annotation.data());
1273 }
1275 /** Update the position of the curve drag point such that it is over the nearest
1276 * point of the path. */
1277 void PathManipulator::_updateDragPoint(Geom::Point const &evp)
1278 {
1279 // TODO find a way to make this faster (no transform required)
1280 Geom::PathVector pv = _spcurve->get_pathvector() * (_edit_transform * _i2d_transform);
1281 boost::optional<Geom::PathVectorPosition> pvp
1282 = Geom::nearestPoint(pv, _desktop->w2d(evp));
1283 if (!pvp) return;
1284 Geom::Point nearest_point = _desktop->d2w(pv.at(pvp->path_nr).pointAt(pvp->t));
1286 double fracpart;
1287 std::list<SubpathPtr>::iterator spi = _subpaths.begin();
1288 for (unsigned i = 0; i < pvp->path_nr; ++i, ++spi) {}
1289 NodeList::iterator first = (*spi)->before(pvp->t, &fracpart);
1291 double stroke_tolerance = _getStrokeTolerance();
1292 if (Geom::distance(evp, nearest_point) < stroke_tolerance) {
1293 _dragpoint->setVisible(true);
1294 _dragpoint->setPosition(_desktop->w2d(nearest_point));
1295 _dragpoint->setSize(2 * stroke_tolerance);
1296 _dragpoint->setTimeValue(fracpart);
1297 _dragpoint->setIterator(first);
1298 } else {
1299 _dragpoint->setVisible(false);
1300 }
1301 }
1303 /// This is called on zoom change to update the direction arrows
1304 void PathManipulator::_updateOutlineOnZoomChange()
1305 {
1306 if (_show_path_direction) _updateOutline();
1307 }
1309 /** Compute the radius from the edge of the path where clicks chould initiate a curve drag
1310 * or segment selection, in window coordinates. */
1311 double PathManipulator::_getStrokeTolerance()
1312 {
1313 /* Stroke event tolerance is equal to half the stroke's width plus the global
1314 * drag tolerance setting. */
1315 Inkscape::Preferences *prefs = Inkscape::Preferences::get();
1316 double ret = prefs->getIntLimited("/options/dragtolerance/value", 2, 0, 100);
1317 if (_path && !SP_OBJECT_STYLE(_path)->stroke.isNone()) {
1318 ret += SP_OBJECT_STYLE(_path)->stroke_width.computed * 0.5
1319 * (_edit_transform * _i2d_transform).descrim() // scale to desktop coords
1320 * _desktop->current_zoom(); // == _d2w.descrim() - scale to window coords
1321 }
1322 return ret;
1323 }
1325 } // namespace UI
1326 } // namespace Inkscape
1328 /*
1329 Local Variables:
1330 mode:c++
1331 c-file-style:"stroustrup"
1332 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
1333 indent-tabs-mode:nil
1334 fill-column:99
1335 End:
1336 */
1337 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :