1 /**
2 * \file src/snapper.cpp
3 * \brief Snapper class.
4 *
5 * Authors:
6 * Carl Hetherington <inkscape@carlh.net>
7 *
8 * Released under GNU GPL, read the file 'COPYING' for more information.
9 */
11 #include "libnr/nr-values.h"
12 #include "sp-namedview.h"
14 Inkscape::Snapper::PointType const Inkscape::Snapper::BBOX_POINT = 0x1;
15 Inkscape::Snapper::PointType const Inkscape::Snapper::SNAP_POINT = 0x2;
17 /**
18 * Construct new Snapper for named view.
19 * \param nv Named view.
20 * \param d Snap distance.
21 */
22 Inkscape::Snapper::Snapper(SPNamedView const *nv, NR::Coord const d) : _named_view(nv), _distance(d)
23 {
24 g_assert(_named_view != NULL);
25 g_assert(SP_IS_NAMEDVIEW(_named_view));
27 setSnapTo(BBOX_POINT, true);
28 }
30 /**
31 * Set snap distance.
32 * \param d New snap distance (desktop coordinates)
33 */
34 void Inkscape::Snapper::setDistance(NR::Coord const d)
35 {
36 _distance = d;
37 }
39 /**
40 * \return Snap distance (desktop coordinates)
41 */
42 NR::Coord Inkscape::Snapper::getDistance() const
43 {
44 return _distance;
45 }
47 /**
48 * Turn on/off snapping of specific point types.
49 * \param t Point type.
50 * \param s true to snap to this point type, otherwise false;
51 */
52 void Inkscape::Snapper::setSnapTo(PointType t, bool s)
53 {
54 if (s) {
55 _snap_to |= t;
56 } else {
57 _snap_to &= ~t;
58 }
59 }
61 /**
62 * \param t Point type.
63 * \return true if snapper will snap this type of point, otherwise false.
64 */
65 bool Inkscape::Snapper::getSnapTo(PointType t) const
66 {
67 return (_snap_to & t);
68 }
70 /**
71 * \return true if this Snapper will snap at least one kind of point.
72 */
73 bool Inkscape::Snapper::willSnapSomething() const
74 {
75 return (_snap_to != 0);
76 }
80 /**
81 * Try to snap a point to whatever this snapper is interested in. Any
82 * snap that occurs will be to the nearest "interesting" thing (e.g. a
83 * grid or guide line)
84 *
85 * \param t Point type.
86 * \param p Point to snap (desktop coordinates).
87 * \param it Item that should not be snapped to.
88 * \return Snapped point.
89 */
91 Inkscape::SnappedPoint Inkscape::Snapper::freeSnap(PointType t,
92 NR::Point const &p,
93 SPItem const *it) const
94 {
95 std::list<SPItem const *> lit;
96 lit.push_back(it);
97 return freeSnap(t, p, lit);
98 }
101 /**
102 * Try to snap a point to whatever this snapper is interested in. Any
103 * snap that occurs will be to the nearest "interesting" thing (e.g. a
104 * grid or guide line)
105 *
106 * \param t Point type.
107 * \param p Point to snap (desktop coordinates).
108 * \param it Items that should not be snapped to.
109 * \return Snapped point.
110 */
112 Inkscape::SnappedPoint Inkscape::Snapper::freeSnap(PointType t,
113 NR::Point const &p,
114 std::list<SPItem const *> const &it) const
115 {
116 if (getSnapTo(t) == false) {
117 return SnappedPoint(p, NR_HUGE);
118 }
120 return _doFreeSnap(p, it);
121 }
126 /**
127 * Try to snap a point to whatever this snapper is interested in, where
128 * the snap point is constrained to lie along a specified vector from the
129 * original point.
130 *
131 * \param p Point to snap (desktop coordinates).
132 * \param c Vector to constrain the snap to.
133 * \param it Items that should not be snapped to.
134 * \return Snapped point.
135 */
137 Inkscape::SnappedPoint Inkscape::Snapper::constrainedSnap(PointType t,
138 NR::Point const &p,
139 NR::Point const &c,
140 SPItem const *it) const
141 {
142 std::list<SPItem const *> lit;
143 lit.push_back(it);
144 return constrainedSnap(t, p, c, lit);
145 }
148 /**
149 * Try to snap a point to whatever this snapper is interested in, where
150 * the snap point is constrained to lie along a specified vector from the
151 * original point.
152 *
153 * \param p Point to snap (desktop coordinates).
154 * \param c Vector to constrain the snap to.
155 * \param it Items that should not be snapped to.
156 * \return Snapped point.
157 */
159 Inkscape::SnappedPoint Inkscape::Snapper::constrainedSnap(PointType t,
160 NR::Point const &p,
161 NR::Point const &c,
162 std::list<SPItem const *> const &it) const
163 {
164 if (getSnapTo(t) == false) {
165 return SnappedPoint(p, NR_HUGE);
166 }
168 return _doConstrainedSnap(p, c, it);
169 }
171 /*
172 Local Variables:
173 mode:c++
174 c-file-style:"stroustrup"
175 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
176 indent-tabs-mode:nil
177 fill-column:99
178 End:
179 */
180 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :