X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=src%2Fline-snapper.cpp;h=219bc7482d7501c54d6259087a488acce0d64d0f;hb=57eb32794c2df43d60ee8f0a9aa8576567358ce6;hp=383c1fb96725f731c9c62574a00e5422a033d095;hpb=6b15695578f07a3f72c4c9475c1a261a3021472a;p=inkscape.git diff --git a/src/line-snapper.cpp b/src/line-snapper.cpp index 383c1fb96..219bc7482 100644 --- a/src/line-snapper.cpp +++ b/src/line-snapper.cpp @@ -1,71 +1,99 @@ +/** + * \file line-snapper.cpp + * \brief LineSnapper class. + * + * Authors: + * Diederik van Lierop + * And others... + * + * Copyright (C) 1999-2007 Authors + * + * Released under GNU GPL, read the file 'COPYING' for more information + */ + #include "libnr/nr-values.h" #include "libnr/nr-point-fns.h" -#include "geom.h" +#include <2geom/geom.h> #include "line-snapper.h" +#include "snapped-line.h" +#include Inkscape::LineSnapper::LineSnapper(SPNamedView const *nv, NR::Coord const d) : Snapper(nv, d) { } -Inkscape::SnappedPoint Inkscape::LineSnapper::_doFreeSnap(NR::Point const &p, - std::list const &it) const +void Inkscape::LineSnapper::_doFreeSnap(SnappedConstraints &sc, + Inkscape::Snapper::PointType const &t, + NR::Point const &p, + bool const &f, + std::vector &points_to_snap, + std::list const &it, + std::vector *unselected_nodes) const { - /* Snap along x (ie to vertical lines) */ - Inkscape::SnappedPoint const v = _doConstrainedSnap(p, component_vectors[NR::X], it); - /* Snap along y (ie to horizontal lines) */ - Inkscape::SnappedPoint const h = _doConstrainedSnap(p, component_vectors[NR::Y], it); - - /* If we snapped to both, combine the two results. This is so that, for example, - ** we snap nicely to the intersection of two guidelines. - */ - if (v.getDistance() < NR_HUGE && h.getDistance() < NR_HUGE) { - return SnappedPoint(NR::Point(v.getPoint()[NR::X], h.getPoint()[NR::Y]), hypot(v.getDistance(), h.getDistance())); - } + /* Get the lines that we will try to snap to */ + const LineList lines = _getSnapLines(p); - /* If we snapped to a vertical line, return that */ - if (v.getDistance() < NR_HUGE) { - return v; - } + // std::cout << "snap point " << p << " to: " << std::endl; - /* Otherwise just return any horizontal snap; if we didn't snap to that either - ** we haven't snapped to anything. - */ - return h; + for (LineList::const_iterator i = lines.begin(); i != lines.end(); i++) { + NR::Point const p1 = i->second; // point at guide/grid line + NR::Point const p2 = p1 + NR::rot90(i->first); // 2nd point at guide/grid line + // std::cout << " line through " << i->second << " with normal " << i->first; + g_assert(i->first != NR::Point(0,0)); // we cannot project on an linesegment of zero length + + NR::Point const p_proj = project_on_linesegment(p, p1, p2); + NR::Coord const dist = NR::L2(p_proj - p); + //Store any line that's within snapping range + if (dist < getSnapperTolerance()) { + _addSnappedLine(sc, p_proj, dist, i->first, i->second); + // std::cout << " -> distance = " << dist; + } + // std::cout << std::endl; + } } -Inkscape::SnappedPoint Inkscape::LineSnapper::_doConstrainedSnap(NR::Point const &p, - NR::Point const &c, - std::list const &it) const -{ - Inkscape::SnappedPoint s = SnappedPoint(p, NR_HUGE); - - NR::Point const v = NR::unit_vector(c); +void Inkscape::LineSnapper::_doConstrainedSnap(SnappedConstraints &sc, + Inkscape::Snapper::PointType const &/*t*/, + NR::Point const &p, + bool const &/*f*/, + std::vector &/*points_to_snap*/, + ConstraintLine const &c, + std::list const &/*it*/) const +{ /* Get the lines that we will try to snap to */ const LineList lines = _getSnapLines(p); for (LineList::const_iterator i = lines.begin(); i != lines.end(); i++) { - - /* Normal to the line we're trying to snap along */ - NR::Point const n(NR::rot90(v)); - - /* Hence constant term of the line we're trying to snap along */ - NR::Coord const q = dot(n, p); - - /* Try to intersect this line with the target line */ - NR::Point t = p; - IntersectorKind const k = intersector_line_intersection(n, q, component_vectors[i->first], i->second, t); - - if (k == INTERSECTS) { - const NR::Coord dist = L2(t - p); - if (dist < getDistance() && dist < s.getDistance() ) { - s = SnappedPoint(t, dist); + if (NR::L2(c.getDirection()) > 0) { // Can't do a constrained snap without a constraint + /* Normal to the line we're trying to snap along */ + NR::Point const n(NR::rot90(NR::unit_vector(c.getDirection()))); + + NR::Point const point_on_line = c.hasPoint() ? c.getPoint() : p; + + /* Constant term of the line we're trying to snap along */ + NR::Coord const q0 = dot(n, point_on_line); + /* Constant term of the grid or guide line */ + NR::Coord const q1 = dot(i->first, i->second); + + /* Try to intersect this line with the target line */ + Geom::Point t_2geom(NR_HUGE, NR_HUGE); + Geom::IntersectorKind const k = Geom::line_intersection(n.to_2geom(), q0, i->first.to_2geom(), q1, t_2geom); + NR::Point t(t_2geom); + + if (k == Geom::intersects) { + const NR::Coord dist = L2(t - p); + if (dist < getSnapperTolerance()) { + // When doing a constrained snap, we're already at an intersection. + // This snappoint is therefore fully constrained, so there's no need + // to look for additional intersections; just return the snapped point + // and forget about the line + sc.points.push_back(SnappedPoint(t, dist, getSnapperTolerance(), getSnapperAlwaysSnap())); + } } } } - - return s; } /*