1 #ifndef SEEN_SNAPPER_H
2 #define SEEN_SNAPPER_H
4 /**
5 * \file src/snapper.h
6 * \brief Snapper class.
7 *
8 * Authors:
9 * Carl Hetherington <inkscape@carlh.net>
10 * Diederik van Lierop <mail@diedenrezi.nl>
11 *
12 * Released under GNU GPL, read the file 'COPYING' for more information.
13 */
15 #include <map>
16 #include <list>
17 #include "libnr/nr-coord.h"
18 #include "libnr/nr-point.h"
19 #include <boost/optional.hpp>
21 #include "snapped-point.h"
22 #include "snapped-line.h"
23 #include "snapped-curve.h"
24 #include "snap-preferences.h"
26 struct SnappedConstraints {
27 std::list<Inkscape::SnappedPoint> points;
28 std::list<Inkscape::SnappedLineSegment> lines;
29 std::list<Inkscape::SnappedLine> grid_lines;
30 std::list<Inkscape::SnappedLine> guide_lines;
31 std::list<Inkscape::SnappedCurve> curves;
32 };
34 class SnapManager;
35 struct SPItem;
37 namespace Inkscape
38 {
40 /// Parent for classes that can snap points to something
41 class Snapper
42 {
43 public:
44 Snapper() {}
45 Snapper(SnapManager *sm, ::Geom::Coord const t);
46 virtual ~Snapper() {}
48 virtual Geom::Coord getSnapperTolerance() const = 0; //returns the tolerance of the snapper in screen pixels (i.e. independent of zoom)
49 virtual bool getSnapperAlwaysSnap() const = 0; //if true, then the snapper will always snap, regardless of its tolerance
51 /**
52 * \return true if this Snapper will snap at least one kind of point.
53 */
54 virtual bool ThisSnapperMightSnap() const {return _snap_enabled;} // will likely be overridden by derived classes
56 void setEnabled(bool s); // This is only used for grids, for which snapping can be enabled individually
57 bool getEnabled() const {return _snap_enabled;}
59 virtual void freeSnap(SnappedConstraints &/*sc*/,
60 SnapPreferences::PointType const &/*t*/,
61 Geom::Point const &/*p*/,
62 SnapSourceType const &/*source_type*/,
63 bool const &/*first_point*/,
64 Geom::OptRect const &/*bbox_to_snap*/,
65 std::vector<SPItem const *> const */*it*/,
66 std::vector<std::pair<Geom::Point, int> > */*unselected_nodes*/) const {};
68 class ConstraintLine
69 {
70 public:
71 ConstraintLine(Geom::Point const &d) : _has_point(false), _direction(d) {}
72 ConstraintLine(Geom::Point const &p, Geom::Point const &d) : _has_point(true), _point(p), _direction(d) {}
74 bool hasPoint() const {
75 return _has_point;
76 }
78 Geom::Point getPoint() const {
79 return _point;
80 }
82 Geom::Point getDirection() const {
83 return _direction;
84 }
86 void setPoint(Geom::Point const &p) {
87 _point = p;
88 _has_point = true;
89 }
91 private:
93 bool _has_point;
94 Geom::Point _point;
95 Geom::Point _direction;
96 };
98 virtual void constrainedSnap(SnappedConstraints &/*sc*/,
99 SnapPreferences::PointType const &/*t*/,
100 Geom::Point const &/*p*/,
101 SnapSourceType const &/*source_type*/,
102 bool const &/*first_point*/,
103 Geom::OptRect const &/*bbox_to_snap*/,
104 ConstraintLine const &/*c*/,
105 std::vector<SPItem const *> const */*it*/) const {};
107 protected:
108 SnapManager *_snapmanager;
110 bool _snap_enabled; ///< true if this snapper is enabled, otherwise false
111 // This is only used for grids, for which snapping can be enabled individually
112 };
114 }
116 #endif /* !SEEN_SNAPPER_H */
118 /*
119 Local Variables:
120 mode:c++
121 c-file-style:"stroustrup"
122 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
123 indent-tabs-mode:nil
124 fill-column:99
125 End:
126 */
127 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :