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diff --git a/src/snapped-line.cpp b/src/snapped-line.cpp
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/**
+ * \file src/snapped-line.cpp
+ * SnappedLine class.
+ *
+ * Authors:
+ * Diederik van Lierop <mail@diedenrezi.nl>
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include "snapped-line.h"
+
+Inkscape::SnappedLineSegment::SnappedLineSegment(Geom::Point const &snapped_point, Geom::Coord const &snapped_distance, SnapSourceType const &source, long source_num, SnapTargetType const &target, Geom::Coord const &snapped_tolerance, bool const &always_snap, Geom::Point const &start_point_of_line, Geom::Point const &end_point_of_line)
+ : _start_point_of_line(start_point_of_line), _end_point_of_line(end_point_of_line)
+{
+ _point = snapped_point;
+ _source = source;
+ _source_num = source_num;
+ _target = target;
+ _distance = snapped_distance;
+ _tolerance = std::max(snapped_tolerance, 1.0);
+ _always_snap = always_snap;
+ _at_intersection = false;
+ _second_distance = Geom::infinity();
+ _second_tolerance = 1;
+ _second_always_snap = false;
+}
+
+Inkscape::SnappedLineSegment::SnappedLineSegment()
+{
+ _source = SNAPSOURCE_UNDEFINED;
+ _source_num = -1;
+ _target = SNAPTARGET_UNDEFINED;
+ _distance = Geom::infinity();
+ _tolerance = 1;
+ _always_snap = false;
+ _at_intersection = false;
+ _second_distance = Geom::infinity();
+ _second_tolerance = 1;
+ _second_always_snap = false;
+}
+
+
+Inkscape::SnappedLineSegment::~SnappedLineSegment()
+= default;
+
+Inkscape::SnappedPoint Inkscape::SnappedLineSegment::intersect(SnappedLineSegment const &line) const
+{
+ Geom::OptCrossing inters = Geom::OptCrossing(); // empty by default
+ try
+ {
+ inters = Geom::intersection(getLineSegment(), line.getLineSegment());
+ }
+ catch (Geom::InfiniteSolutions &e)
+ {
+ // We're probably dealing with parallel lines, so they don't really cross
+ inters = Geom::OptCrossing();
+ }
+
+ if (inters) {
+ Geom::Point inters_pt = getLineSegment().pointAt((*inters).ta);
+ /* If a snapper has been told to "always snap", then this one should be preferred
+ * over the other, if that other one has not been told so. (The preferred snapper
+ * will be labeled "primary" below)
+ */
+ bool const c1 = this->getAlwaysSnap() && !line.getAlwaysSnap(); //do not use _tolerance directly!
+ /* If neither or both have been told to "always snap", then cast a vote based on
+ * the snapped distance. For this we should consider the distance to the snapped
+ * line, not the distance to the intersection.
+ * See the comment in Inkscape::SnappedLine::intersect
+ */
+ bool const c2 = _distance < line.getSnapDistance();
+ bool const use_this_as_primary = c1 || c2;
+ Inkscape::SnappedLineSegment const *primarySLS = use_this_as_primary ? this : &line;
+ Inkscape::SnappedLineSegment const *secondarySLS = use_this_as_primary ? &line : this;
+ Geom::Coord primaryDist = use_this_as_primary ? Geom::L2(inters_pt - this->getPoint()) : Geom::L2(inters_pt - line.getPoint());
+ Geom::Coord secondaryDist = use_this_as_primary ? Geom::L2(inters_pt - line.getPoint()) : Geom::L2(inters_pt - this->getPoint());
+ return SnappedPoint(inters_pt, SNAPSOURCE_UNDEFINED, primarySLS->getSourceNum(), SNAPTARGET_PATH_INTERSECTION, primaryDist, primarySLS->getTolerance(), primarySLS->getAlwaysSnap(), true, false, true,
+ secondaryDist, secondarySLS->getTolerance(), secondarySLS->getAlwaysSnap());
+ }
+
+ // No intersection
+ return SnappedPoint(Geom::Point(Geom::infinity(), Geom::infinity()), SNAPSOURCE_UNDEFINED, 0, SNAPTARGET_UNDEFINED, Geom::infinity(), 0, false, false, false, false, Geom::infinity(), 0, false);
+};
+
+
+
+Inkscape::SnappedLine::SnappedLine(Geom::Point const &snapped_point, Geom::Coord const &snapped_distance, SnapSourceType const &source, long source_num, SnapTargetType const &target, Geom::Coord const &snapped_tolerance, bool const &always_snap, Geom::Point const &normal_to_line, Geom::Point const &point_on_line)
+ : _normal_to_line(normal_to_line), _point_on_line(point_on_line)
+{
+ _source = source;
+ _source_num = source_num;
+ _target = target;
+ _distance = snapped_distance;
+ _tolerance = std::max(snapped_tolerance, 1.0);
+ _always_snap = always_snap;
+ _second_distance = Geom::infinity();
+ _second_tolerance = 1;
+ _second_always_snap = false;
+ _point = snapped_point;
+ _at_intersection = false;
+}
+
+Inkscape::SnappedLine::SnappedLine()
+{
+ _source = SNAPSOURCE_UNDEFINED;
+ _source_num = -1;
+ _target = SNAPTARGET_UNDEFINED;
+ _distance = Geom::infinity();
+ _tolerance = 1;
+ _always_snap = false;
+ _second_distance = Geom::infinity();
+ _second_tolerance = 1;
+ _second_always_snap = false;
+ _at_intersection = false;
+}
+
+Inkscape::SnappedLine::~SnappedLine()
+= default;
+
+Inkscape::SnappedPoint Inkscape::SnappedLine::intersect(SnappedLine const &line) const
+{
+ // Calculate the intersection of two lines, which are both within snapping range
+ // One could be a grid line, whereas the other could be a guide line
+ // The point of intersection should be considered for snapping, but might be outside the snapping range
+
+ Geom::OptCrossing inters = Geom::OptCrossing(); // empty by default
+ try
+ {
+ inters = Geom::intersection(getLine(), line.getLine());
+ }
+ catch (Geom::InfiniteSolutions &e)
+ {
+ // We're probably dealing with parallel lines, so they don't really cross
+ inters = Geom::OptCrossing();
+ }
+
+ if (inters) {
+ Geom::Point inters_pt = getLine().pointAt((*inters).ta);
+ /* If a snapper has been told to "always snap", then this one should be preferred
+ * over the other, if that other one has not been told so. (The preferred snapper
+ * will be labelled "primary" below)
+ */
+ bool const c1 = this->getAlwaysSnap() && !line.getAlwaysSnap();
+ /* If neither or both have been told to "always snap", then cast a vote based on
+ * the snapped distance. For this we should consider the distance to the snapped
+ * line or to the intersection
+ */
+ bool const c2 = _distance < line.getSnapDistance();
+ bool const use_this_as_primary = c1 || c2;
+ Inkscape::SnappedLine const *primarySL = use_this_as_primary ? this : &line;
+ Inkscape::SnappedLine const *secondarySL = use_this_as_primary ? &line : this;
+ Geom::Coord primaryDist = use_this_as_primary ? Geom::L2(inters_pt - this->getPoint()) : Geom::L2(inters_pt - line.getPoint());
+ Geom::Coord secondaryDist = use_this_as_primary ? Geom::L2(inters_pt - line.getPoint()) : Geom::L2(inters_pt - this->getPoint());
+ return SnappedPoint(inters_pt, Inkscape::SNAPSOURCE_UNDEFINED, primarySL->getSourceNum(), Inkscape::SNAPTARGET_UNDEFINED, primaryDist, primarySL->getTolerance(), primarySL->getAlwaysSnap(), true, false, true,
+ secondaryDist, secondarySL->getTolerance(), secondarySL->getAlwaysSnap());
+ // The type of the snap target is yet undefined, as we cannot tell whether
+ // we're snapping to grid or the guide lines; must be set by on a higher level
+ }
+
+ // No intersection
+ return SnappedPoint(Geom::Point(Geom::infinity(), Geom::infinity()), SNAPSOURCE_UNDEFINED, 0, SNAPTARGET_UNDEFINED, Geom::infinity(), 0, false, false, false, false, Geom::infinity(), 0, false);
+}
+
+// search for the closest snapped line segment
+bool getClosestSLS(std::list<Inkscape::SnappedLineSegment> const &list, Inkscape::SnappedLineSegment &result)
+{
+ bool success = false;
+
+ for (std::list<Inkscape::SnappedLineSegment>::const_iterator i = list.begin(); i != list.end(); ++i) {
+ if ((i == list.begin()) || (*i).getSnapDistance() < result.getSnapDistance()) {
+ result = *i;
+ success = true;
+ }
+ }
+
+ return success;
+}
+
+// search for the closest intersection of two snapped line segments, which are both member of the same collection
+bool getClosestIntersectionSLS(std::list<Inkscape::SnappedLineSegment> const &list, Inkscape::SnappedPoint &result)
+{
+ bool success = false;
+
+ for (std::list<Inkscape::SnappedLineSegment>::const_iterator i = list.begin(); i != list.end(); ++i) {
+ std::list<Inkscape::SnappedLineSegment>::const_iterator j = i;
+ ++j;
+ for (; j != list.end(); ++j) {
+ Inkscape::SnappedPoint sp = (*i).intersect(*j);
+ if (sp.getAtIntersection()) {
+ // if it's the first point
+ bool const c1 = !success;
+ // or, if it's closer
+ bool const c2 = sp.getSnapDistance() < result.getSnapDistance();
+ // or, if it's just then look at the other distance
+ // (only relevant for snapped points which are at an intersection
+ bool const c3 = (sp.getSnapDistance() == result.getSnapDistance()) && (sp.getSecondSnapDistance() < result.getSecondSnapDistance());
+ // then prefer this point over the previous one
+ if (c1 || c2 || c3) {
+ result = sp;
+ success = true;
+ }
+ }
+ }
+ }
+
+ return success;
+}
+
+// search for the closest snapped line
+bool getClosestSL(std::list<Inkscape::SnappedLine> const &list, Inkscape::SnappedLine &result)
+{
+ bool success = false;
+
+ for (std::list<Inkscape::SnappedLine>::const_iterator i = list.begin(); i != list.end(); ++i) {
+ if ((i == list.begin()) || (*i).getSnapDistance() < result.getSnapDistance()) {
+ result = *i;
+ success = true;
+ }
+ }
+
+ return success;
+}
+
+// search for the closest intersection of two snapped lines, which are both member of the same collection
+bool getClosestIntersectionSL(std::list<Inkscape::SnappedLine> const &list, Inkscape::SnappedPoint &result)
+{
+ bool success = false;
+
+ for (std::list<Inkscape::SnappedLine>::const_iterator i = list.begin(); i != list.end(); ++i) {
+ std::list<Inkscape::SnappedLine>::const_iterator j = i;
+ ++j;
+ for (; j != list.end(); ++j) {
+ Inkscape::SnappedPoint sp = (*i).intersect(*j);
+ if (sp.getAtIntersection()) {
+ // if it's the first point
+ bool const c1 = !success;
+ // or, if it's closer
+ bool const c2 = sp.getSnapDistance() < result.getSnapDistance();
+ // or, if it's just then look at the other distance
+ // (only relevant for snapped points which are at an intersection
+ bool const c3 = (sp.getSnapDistance() == result.getSnapDistance()) && (sp.getSecondSnapDistance() < result.getSecondSnapDistance());
+ // then prefer this point over the previous one
+ if (c1 || c2 || c3) {
+ result = sp;
+ success = true;
+ }
+ }
+ }
+ }
+
+ return success;
+}
+
+// search for the closest intersection of two snapped lines, which are in two different collections
+bool getClosestIntersectionSL(std::list<Inkscape::SnappedLine> const &list1, std::list<Inkscape::SnappedLine> const &list2, Inkscape::SnappedPoint &result)
+{
+ bool success = false;
+
+ for (const auto & i : list1) {
+ for (const auto & j : list2) {
+ Inkscape::SnappedPoint sp = i.intersect(j);
+ if (sp.getAtIntersection()) {
+ // if it's the first point
+ bool const c1 = !success;
+ // or, if it's closer
+ bool const c2 = sp.getSnapDistance() < result.getSnapDistance();
+ // or, if it's just then look at the other distance
+ // (only relevant for snapped points which are at an intersection
+ bool const c3 = (sp.getSnapDistance() == result.getSnapDistance()) && (sp.getSecondSnapDistance() < result.getSecondSnapDistance());
+ // then prefer this point over the previous one
+ if (c1 || c2 || c3) {
+ result = sp;
+ success = true;
+ }
+ }
+ }
+ }
+
+ return success;
+}
+
+/*
+ Local Variables:
+ mode:c++
+ c-file-style:"stroustrup"
+ c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+ indent-tabs-mode:nil
+ fill-column:99
+ End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :
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