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diff --git a/src/snapped-line.cpp b/src/snapped-line.cpp
index 7ae94e4f4b79181834cc5d0a36e8f4b5aa6af8e8..b6a5c2f9f5986f5b71692a808fad6a525cf26a80 100644 (file)
--- a/src/snapped-line.cpp
+++ b/src/snapped-line.cpp
#include <2geom/geom.h>
#include "libnr/nr-values.h"
-Inkscape::SnappedLineSegment::SnappedLineSegment(NR::Point snapped_point, NR::Coord snapped_distance, NR::Point start_point_of_line, NR::Point end_point_of_line)
+Inkscape::SnappedLineSegment::SnappedLineSegment(NR::Point snapped_point, NR::Coord snapped_distance, NR::Coord snapped_tolerance, bool always_snap, NR::Point start_point_of_line, NR::Point end_point_of_line)
: _start_point_of_line(start_point_of_line), _end_point_of_line(end_point_of_line)
{
- _distance = snapped_distance;
_point = snapped_point;
+ _distance = snapped_distance;
+ _tolerance = snapped_tolerance;
+ _always_snap = always_snap;
_at_intersection = false;
+ _second_distance = NR_HUGE;
+ _second_tolerance = 0;
+ _second_always_snap = false;
}
Inkscape::SnappedLineSegment::SnappedLineSegment()
{
_start_point_of_line = NR::Point(0,0);
_end_point_of_line = NR::Point(0,0);
- _distance = NR_HUGE;
_point = NR::Point(0,0);
+ _distance = NR_HUGE;
+ _tolerance = 0;
+ _always_snap = false;
_at_intersection = false;
+ _second_distance = NR_HUGE;
+ _second_tolerance = 0;
+ _second_always_snap = false;
}
Inkscape::SnappedPoint Inkscape::SnappedLineSegment::intersect(SnappedLineSegment const &line) const
{
Geom::Point intersection_2geom(NR_HUGE, NR_HUGE);
- NR::Coord distance = NR_HUGE;
-
Geom::IntersectorKind result = segment_intersect(_start_point_of_line.to_2geom(), _end_point_of_line.to_2geom(),
line._start_point_of_line.to_2geom(), line._end_point_of_line.to_2geom(),
intersection_2geom);
NR::Point intersection(intersection_2geom);
if (result == Geom::intersects) {
- /* The relevant snapped distance is the distance to the closest snapped line, not the
- distance to the intersection. See the comment in Inkscape::SnappedLine::intersect
+ /* 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(); //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
*/
- distance = std::min(_distance, line.getDistance());
+ bool const c2 = _distance < line.getDistance();
+ 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;
+ return SnappedPoint(intersection, primarySLS->getDistance(), primarySLS->getTolerance(), primarySLS->getAlwaysSnap(), true,
+ secondarySLS->getDistance(), secondarySLS->getTolerance(), secondarySLS->getAlwaysSnap());
}
- return SnappedPoint(intersection, distance, result == Geom::intersects);
+
+ // No intersection
+ return SnappedPoint(intersection, NR_HUGE, 0, false, false, NR_HUGE, 0, false);
};
-Inkscape::SnappedLine::SnappedLine(NR::Point snapped_point, NR::Coord snapped_distance, NR::Point normal_to_line, NR::Point point_on_line)
+Inkscape::SnappedLine::SnappedLine(NR::Point snapped_point, NR::Coord snapped_distance, NR::Coord snapped_tolerance, bool always_snap, NR::Point normal_to_line, NR::Point point_on_line)
: _normal_to_line(normal_to_line), _point_on_line(point_on_line)
{
_distance = snapped_distance;
+ _tolerance = snapped_tolerance;
+ _always_snap = always_snap;
+ _second_distance = NR_HUGE;
+ _second_tolerance = 0;
+ _second_always_snap = false;
_point = snapped_point;
_at_intersection = false;
}
_normal_to_line = NR::Point(0,0);
_point_on_line = NR::Point(0,0);
_distance = NR_HUGE;
+ _tolerance = 0;
+ _always_snap = false;
+ _second_distance = NR_HUGE;
+ _second_tolerance = 0;
+ _second_always_snap = false;
_point = NR::Point(0,0);
_at_intersection = false;
}
Inkscape::SnappedPoint Inkscape::SnappedLine::intersect(SnappedLine const &line) const
{
- // Calculate the intersection of to lines, which are both within snapping range
+ // 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::Point intersection_2geom(NR_HUGE, NR_HUGE);
- NR::Coord distance = NR_HUGE;
-
- Geom::IntersectorKind result = Geom::line_intersection(getNormal().to_2geom(), getConstTerm(),
+ Geom::IntersectorKind result = Geom::line_intersection(getNormal().to_2geom(), getConstTerm(),
line.getNormal().to_2geom(), line.getConstTerm(), intersection_2geom);
NR::Point intersection(intersection_2geom);
if (result == Geom::intersects) {
- /* The relevant snapped distance is the distance to the closest snapped line, not the
- distance to the intersection. For example, when a box is almost aligned with a grid
- in both horizontal and vertical directions, the distance to the intersection of the
- grid lines will always be larger then the distance to a grid line. We will be snapping
- to the closest snapped point however, so if we ever want to snap to the intersection
- then the distance to it should at least be equal to the other distance, not greater
- than it, as that would rule the intersection out
- */
- distance = std::min(_distance, line.getDistance());
- }
-
- return SnappedPoint(intersection, distance, result == Geom::intersects);
+ /* 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, not the distance to the intersection.
+ *
+ * The relevant snapped distance is the distance to the closest snapped line, not the
+ * distance to the intersection. For example, when a box is almost aligned with a grid
+ * in both horizontal and vertical directions, the distance to the intersection of the
+ * grid lines will always be larger then the distance to a grid line. We will be snapping
+ * to the closest snapped point however, so if we ever want to snap to the intersection
+ * then the distance to it should at least be equal to the other distance, not greater
+ * than it, as that would rule the intersection out when comparing it with regular snappoint,
+ * as the latter will always be closer
+ */
+ bool const c2 = _distance < line.getDistance();
+ 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;
+ return SnappedPoint(intersection, primarySL->getDistance(), primarySL->getTolerance(), primarySL->getAlwaysSnap(), true,
+ secondarySL->getDistance(), secondarySL->getTolerance(), secondarySL->getAlwaysSnap());
+ }
+
+ // No intersection
+ return SnappedPoint(intersection, NR_HUGE, 0, false, false, NR_HUGE, 0, false);
}
// search for the closest snapped line segment
@@ -129,8 +176,15 @@ bool getClosestIntersectionSLS(std::list<Inkscape::SnappedLineSegment> &list, In
for (; j != list.end(); j++) {
Inkscape::SnappedPoint sp = (*i).intersect(*j);
if (sp.getAtIntersection()) {
- if (!success || sp.getDistance() < result.getDistance()) {
- // !success because the first intersection cannot be compared to a previous one
+ // if it's the first point
+ bool const c1 = !success;
+ // or, if it's closer
+ bool const c2 = sp.getDistance() < result.getDistance();
+ // 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.getDistance() == result.getDistance()) && (sp.getSecondDistance() < result.getSecondDistance());
+ // then prefer this point over the previous one
+ if (c1 || c2 || c3) {
result = sp;
success = true;
}
@@ -167,8 +221,15 @@ bool getClosestIntersectionSL(std::list<Inkscape::SnappedLine> &list, Inkscape::
for (; j != list.end(); j++) {
Inkscape::SnappedPoint sp = (*i).intersect(*j);
if (sp.getAtIntersection()) {
- if (!success || sp.getDistance() < result.getDistance()) {
- // !success because the first intersection cannot be compared to a previous one
+ // if it's the first point
+ bool const c1 = !success;
+ // or, if it's closer
+ bool const c2 = sp.getDistance() < result.getDistance();
+ // 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.getDistance() == result.getDistance()) && (sp.getSecondDistance() < result.getSecondDistance());
+ // then prefer this point over the previous one
+ if (c1 || c2 || c3) {
result = sp;
success = true;
}
@@ -188,8 +249,15 @@ bool getClosestIntersectionSL(std::list<Inkscape::SnappedLine> &list1, std::list
for (std::list<Inkscape::SnappedLine>::const_iterator j = list2.begin(); j != list2.end(); j++) {
Inkscape::SnappedPoint sp = (*i).intersect(*j);
if (sp.getAtIntersection()) {
- if (!success || sp.getDistance() < result.getDistance()) {
- // !success because the first intersection cannot be compared to a previous one
+ // if it's the first point
+ bool const c1 = !success;
+ // or, if it's closer
+ bool const c2 = sp.getDistance() < result.getDistance();
+ // 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.getDistance() == result.getDistance()) && (sp.getSecondDistance() < result.getSecondDistance());
+ // then prefer this point over the previous one
+ if (c1 || c2 || c3) {
result = sp;
success = true;
}