1 /** @file
2 * Editable node and associated data structures.
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 #ifndef SEEN_UI_TOOL_NODE_H
12 #define SEEN_UI_TOOL_NODE_H
14 #include <glib.h>
15 #include <iterator>
16 #include <iosfwd>
17 #include <stdexcept>
18 #include <tr1/functional>
19 #include <boost/utility.hpp>
20 #include <boost/shared_ptr.hpp>
21 #include <boost/optional.hpp>
22 #include <boost/operators.hpp>
23 #include "snapped-point.h"
24 #include "ui/tool/selectable-control-point.h"
25 #include "ui/tool/node-types.h"
28 namespace Inkscape {
29 namespace UI {
30 template <typename> class NodeIterator;
31 }
32 }
34 namespace std {
35 namespace tr1 {
36 template <typename N> struct hash< Inkscape::UI::NodeIterator<N> >;
37 }
38 }
40 namespace Inkscape {
41 namespace UI {
43 class PathManipulator;
44 class MultiPathManipulator;
46 class Node;
47 class Handle;
48 class NodeList;
49 class SubpathList;
50 template <typename> class NodeIterator;
52 std::ostream &operator<<(std::ostream &, NodeType);
54 /*
55 template <typename T>
56 struct ListMember {
57 T *next;
58 T *prev;
59 };
60 struct SubpathMember : public ListMember<NodeListMember> {
61 Subpath *list;
62 };
63 struct SubpathListMember : public ListMember<SubpathListMember> {
64 SubpathList *list;
65 };
66 */
68 struct ListNode {
69 ListNode *ln_next;
70 ListNode *ln_prev;
71 NodeList *ln_list;
72 };
74 struct NodeSharedData {
75 SPDesktop *desktop;
76 ControlPointSelection *selection;
77 SPCanvasGroup *node_group;
78 SPCanvasGroup *handle_group;
79 SPCanvasGroup *handle_line_group;
80 };
82 class Handle : public ControlPoint {
83 public:
84 virtual ~Handle();
85 inline Geom::Point relativePos();
86 inline double length();
87 bool isDegenerate() { return _degenerate; }
89 virtual void setVisible(bool);
90 virtual void move(Geom::Point const &p);
92 virtual void setPosition(Geom::Point const &p);
93 inline void setRelativePos(Geom::Point const &p);
94 void setLength(double len);
95 void retract();
96 void setDirection(Geom::Point const &from, Geom::Point const &to);
97 void setDirection(Geom::Point const &dir);
98 Node *parent() { return _parent; }
99 Handle *other();
101 static char const *handle_type_to_localized_string(NodeType type);
102 protected:
103 Handle(NodeSharedData const &data, Geom::Point const &initial_pos, Node *parent);
105 virtual bool _eventHandler(GdkEvent *event);
106 virtual void dragged(Geom::Point &, GdkEventMotion *);
107 virtual bool grabbed(GdkEventMotion *);
108 virtual void ungrabbed(GdkEventButton *);
109 virtual bool clicked(GdkEventButton *);
111 virtual Glib::ustring _getTip(unsigned state);
112 virtual Glib::ustring _getDragTip(GdkEventMotion *event);
113 virtual bool _hasDragTips() { return true; }
114 private:
115 inline PathManipulator &_pm();
116 Node *_parent; // the handle's lifetime does not extend beyond that of the parent node,
117 // so a naked pointer is OK and allows setting it during Node's construction
118 SPCanvasItem *_handle_line;
119 bool _degenerate; // this is used often internally so it makes sense to cache this
121 static Geom::Point _saved_other_pos;
122 static double _saved_length;
123 static bool _drag_out;
124 friend class Node;
125 };
127 class Node : ListNode, public SelectableControlPoint {
128 public:
129 Node(NodeSharedData const &data, Geom::Point const &pos);
130 virtual void move(Geom::Point const &p);
131 virtual void transform(Geom::Matrix const &m);
132 virtual Geom::Rect bounds();
134 NodeType type() { return _type; }
135 void setType(NodeType type, bool update_handles = true);
136 void showHandles(bool v);
137 void pickBestType(); // automatically determine the type from handle positions
138 bool isDegenerate() { return _front.isDegenerate() && _back.isDegenerate(); }
139 bool isEndNode();
140 Handle *front() { return &_front; }
141 Handle *back() { return &_back; }
142 Handle *handleToward(Node *to);
143 Node *nodeToward(Handle *h);
144 Handle *handleAwayFrom(Node *to);
145 Node *nodeAwayFrom(Handle *h);
146 NodeList &nodeList() { return *(static_cast<ListNode*>(this)->ln_list); }
147 void sink();
149 static NodeType parse_nodetype(char x);
150 static char const *node_type_to_localized_string(NodeType type);
151 // temporarily public
152 virtual bool _eventHandler(GdkEvent *event);
153 protected:
154 virtual void dragged(Geom::Point &, GdkEventMotion *);
155 virtual bool grabbed(GdkEventMotion *);
156 virtual bool clicked(GdkEventButton *);
158 virtual void _setState(State state);
159 virtual Glib::ustring _getTip(unsigned state);
160 virtual Glib::ustring _getDragTip(GdkEventMotion *event);
161 virtual bool _hasDragTips() { return true; }
162 private:
163 Node(Node const &);
164 void _fixNeighbors(Geom::Point const &old_pos, Geom::Point const &new_pos);
165 void _updateAutoHandles();
166 void _linearGrow(int dir);
167 Node *_next();
168 Node *_prev();
169 Inkscape::SnapSourceType _snapSourceType();
170 Inkscape::SnapTargetType _snapTargetType();
171 inline PathManipulator &_pm();
172 static SPCtrlShapeType _node_type_to_shape(NodeType type);
173 static bool _is_line_segment(Node *first, Node *second);
175 // Handles are always present, but are not visible if they coincide with the node
176 // (are degenerate). A segment that has both handles degenerate is always treated
177 // as a line segment
178 Handle _front; ///< Node handle in the backward direction of the path
179 Handle _back; ///< Node handle in the forward direction of the path
180 NodeType _type; ///< Type of node - cusp, smooth...
181 bool _handles_shown;
182 friend class Handle;
183 friend class NodeList;
184 friend class NodeIterator<Node>;
185 friend class NodeIterator<Node const>;
186 };
188 /// Iterator for editable nodes
189 /** Use this class for all operations that require some knowledge about the node's
190 * neighbors. It is a bidirectional iterator.
191 *
192 * Because paths can be cyclic, node iterators have two different ways to
193 * increment and decrement them. When using ++/--, the end iterator will eventually
194 * be returned. Whent using advance()/retreat(), the end iterator will only be returned
195 * when the path is open. If it's closed, calling advance() will cycle indefinitely.
196 * This is particularly useful for cases where the adjacency of nodes is more important
197 * than their sequence order.
198 *
199 * When @a i is a node iterator, then:
200 * - <code>++i</code> moves the iterator to the next node in sequence order;
201 * - <code>--i</code> moves the iterator to the previous node in sequence order;
202 * - <code>i.next()</code> returns the next node with wrap-around;
203 * - <code>i.prev()</code> returns the previous node with wrap-around;
204 * - <code>i.advance()</code> moves the iterator to the next node with wrap-around;
205 * - <code>i.retreat()</code> moves the iterator to the previous node with wrap-around.
206 *
207 * next() and prev() do not change their iterator. They can return the end iterator
208 * if the path is open.
209 *
210 * Unlike most other iterators, you can check whether you've reached the end of the list
211 * without having access to the iterator's container.
212 * Simply use <code>if (i) { ...</code>
213 * */
214 template <typename N>
215 class NodeIterator
216 : public boost::bidirectional_iterator_helper<NodeIterator<N>, N, std::ptrdiff_t,
217 N *, N &>
218 {
219 public:
220 typedef NodeIterator self;
221 NodeIterator()
222 : _node(0)
223 {}
224 // default copy, default assign
226 self &operator++() {
227 _node = _node->ln_next;
228 return *this;
229 }
230 self &operator--() {
231 _node = _node->ln_prev;
232 return *this;
233 }
234 bool operator==(self const &other) const { return _node == other._node; }
235 N &operator*() const { return *static_cast<N*>(_node); }
236 inline operator bool() const; // define after NodeList
237 /// Get a pointer to the underlying node. Equivalent to <code>&*i</code>.
238 N *get_pointer() const { return static_cast<N*>(_node); }
239 /// @see get_pointer()
240 N *ptr() const { return static_cast<N*>(_node); }
242 self next() const {
243 self r(*this);
244 r.advance();
245 return r;
246 }
247 self prev() const {
248 self r(*this);
249 r.retreat();
250 return r;
251 }
252 self &advance();
253 self &retreat();
254 private:
255 NodeIterator(ListNode const *n)
256 : _node(const_cast<ListNode*>(n))
257 {}
258 ListNode *_node;
259 friend class NodeList;
260 };
262 class NodeList : ListNode, boost::noncopyable, public boost::enable_shared_from_this<NodeList> {
263 public:
264 typedef std::size_t size_type;
265 typedef Node &reference;
266 typedef Node const &const_reference;
267 typedef Node *pointer;
268 typedef Node const *const_pointer;
269 typedef Node value_type;
270 typedef NodeIterator<value_type> iterator;
271 typedef NodeIterator<value_type const> const_iterator;
273 // TODO Lame. Make this private and make SubpathList a factory
274 NodeList(SubpathList &_list);
275 ~NodeList();
277 // iterators
278 iterator begin() { return iterator(ln_next); }
279 iterator end() { return iterator(this); }
280 const_iterator begin() const { return const_iterator(ln_next); }
281 const_iterator end() const { return const_iterator(this); }
283 // size
284 bool empty();
285 size_type size();
287 // extra node-specific methods
288 bool closed();
289 bool degenerate();
290 void setClosed(bool c) { _closed = c; }
291 iterator before(double t, double *fracpart = NULL);
292 const_iterator before(double t, double *fracpart = NULL) const {
293 return const_iterator(before(t, fracpart)._node);
294 }
296 // list operations
297 iterator insert(iterator pos, Node *x);
298 template <class InputIterator>
299 void insert(iterator pos, InputIterator first, InputIterator last) {
300 for (; first != last; ++first) insert(pos, *first);
301 }
302 void splice(iterator pos, NodeList &list);
303 void splice(iterator pos, NodeList &list, iterator i);
304 void splice(iterator pos, NodeList &list, iterator first, iterator last);
305 void reverse();
306 void shift(int n);
307 void push_front(Node *x) { insert(begin(), x); }
308 void pop_front() { erase(begin()); }
309 void push_back(Node *x) { insert(end(), x); }
310 void pop_back() { erase(--end()); }
311 void clear();
312 iterator erase(iterator pos);
313 iterator erase(iterator first, iterator last) {
314 NodeList::iterator ret = first;
315 while (first != last) ret = erase(first++);
316 return ret;
317 }
319 // member access - undefined results when the list is empty
320 Node &front() { return *static_cast<Node*>(ln_next); }
321 Node &back() { return *static_cast<Node*>(ln_prev); }
323 // HACK remove this subpath from its path. This will be removed later.
324 void kill();
325 SubpathList &subpathList() { return _list; }
327 static iterator get_iterator(Node *n) { return iterator(n); }
328 static const_iterator get_iterator(Node const *n) { return const_iterator(n); }
329 static NodeList &get(Node *n);
330 static NodeList &get(iterator const &i);
331 private:
332 // no copy or assign
333 NodeList(NodeList const &);
334 void operator=(NodeList const &);
336 SubpathList &_list;
337 bool _closed;
339 friend class Node;
340 friend class Handle; // required to access handle and handle line groups
341 friend class NodeIterator<Node>;
342 friend class NodeIterator<Node const>;
343 };
345 /** List of node lists. Represents an editable path. */
346 class SubpathList : public std::list< boost::shared_ptr<NodeList> > {
347 public:
348 typedef std::list< boost::shared_ptr<NodeList> > list_type;
350 SubpathList(PathManipulator &pm) : _path_manipulator(pm) {}
351 PathManipulator &pm() { return _path_manipulator; }
353 private:
354 list_type _nodelists;
355 PathManipulator &_path_manipulator;
356 friend class NodeList;
357 friend class Node;
358 friend class Handle;
359 };
363 // define inline Handle funcs after definition of Node
364 inline Geom::Point Handle::relativePos() {
365 return position() - _parent->position();
366 }
367 inline void Handle::setRelativePos(Geom::Point const &p) {
368 setPosition(_parent->position() + p);
369 }
370 inline double Handle::length() {
371 return relativePos().length();
372 }
373 inline PathManipulator &Handle::_pm() {
374 return _parent->_pm();
375 }
376 inline PathManipulator &Node::_pm() {
377 return nodeList().subpathList().pm();
378 }
380 // definitions for node iterator
381 template <typename N>
382 NodeIterator<N>::operator bool() const {
383 return _node && static_cast<ListNode*>(_node->ln_list) != _node;
384 }
385 template <typename N>
386 NodeIterator<N> &NodeIterator<N>::advance() {
387 ++(*this);
388 if (G_UNLIKELY(!*this) && _node->ln_list->closed()) ++(*this);
389 return *this;
390 }
391 template <typename N>
392 NodeIterator<N> &NodeIterator<N>::retreat() {
393 --(*this);
394 if (G_UNLIKELY(!*this) && _node->ln_list->closed()) --(*this);
395 return *this;
396 }
398 } // namespace UI
399 } // namespace Inkscape
401 #endif
403 /*
404 Local Variables:
405 mode:c++
406 c-file-style:"stroustrup"
407 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
408 indent-tabs-mode:nil
409 fill-column:99
410 End:
411 */
412 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :