1 /**
2 * \file guide-snapper.cpp
3 * \brief Snapping things to guides.
4 *
5 * Authors:
6 * Lauris Kaplinski <lauris@kaplinski.com>
7 * Frank Felfe <innerspace@iname.com>
8 * Carl Hetherington <inkscape@carlh.net>
9 *
10 * Copyright (C) 1999-2002 Authors
11 *
12 * Released under GNU GPL, read the file 'COPYING' for more information
13 */
15 #include "libnr/nr-values.h"
16 #include "libnr/nr-point-fns.h"
17 #include "sp-namedview.h"
18 #include "desktop.h"
19 #include "sp-guide.h"
21 Inkscape::GuideSnapper::GuideSnapper(SnapManager *sm, Geom::Coord const d) : LineSnapper(sm, d)
22 {
24 }
26 /**
27 * \return Snap tolerance (desktop coordinates); depends on current zoom so that it's always the same in screen pixels
28 */
29 Geom::Coord Inkscape::GuideSnapper::getSnapperTolerance() const
30 {
31 SPDesktop const *dt = _snapmanager->getDesktop();
32 double const zoom = dt ? dt->current_zoom() : 1;
33 return _snapmanager->snapprefs.getGuideTolerance() / zoom;
34 }
36 bool Inkscape::GuideSnapper::getSnapperAlwaysSnap() const
37 {
38 return _snapmanager->snapprefs.getGuideTolerance() == 10000; //TODO: Replace this threshold of 10000 by a constant; see also tolerance-slider.cpp
39 }
41 Inkscape::GuideSnapper::LineList Inkscape::GuideSnapper::_getSnapLines(Geom::Point const &/*p*/) const
42 {
43 LineList s;
45 if ( NULL == _snapmanager->getNamedView() || ThisSnapperMightSnap() == false) {
46 return s;
47 }
49 for (GSList const *l = _snapmanager->getNamedView()->guides; l != NULL; l = l->next) {
50 SPGuide const *g = SP_GUIDE(l->data);
51 s.push_back(std::make_pair(g->normal_to_line, g->point_on_line));
52 }
54 return s;
55 }
57 /**
58 * \return true if this Snapper will snap at least one kind of point.
59 */
60 bool Inkscape::GuideSnapper::ThisSnapperMightSnap() const
61 {
62 if (_snapmanager->getNamedView() == NULL) {
63 return false;
64 }
66 return (_snap_enabled && _snapmanager->snapprefs.getSnapToGuides() && _snapmanager->snapprefs.getSnapModeBBoxOrNodes() && _snapmanager->getNamedView()->showguides);
67 }
69 void Inkscape::GuideSnapper::_addSnappedLine(SnappedConstraints &sc, Geom::Point const snapped_point, Geom::Coord const snapped_distance, Geom::Point const normal_to_line, Geom::Point const point_on_line) const
70 {
71 SnappedLine dummy = SnappedLine(snapped_point, snapped_distance, getSnapperTolerance(), getSnapperAlwaysSnap(), normal_to_line, point_on_line);
72 sc.guide_lines.push_back(dummy);
73 }
75 /*
76 Local Variables:
77 mode:c++
78 c-file-style:"stroustrup"
79 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
80 indent-tabs-mode:nil
81 fill-column:99
82 End:
83 */
84 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :