diff --git a/src/line-snapper.cpp b/src/line-snapper.cpp
index 72a6cc33d54d5a7b1a2b784bbbf16732abd6e823..5d5a772809d10163018394d3c8a7ea0b0028466f 100644 (file)
--- a/src/line-snapper.cpp
+++ b/src/line-snapper.cpp
* Released under GNU GPL, read the file 'COPYING' for more information
*/
-#include "libnr/nr-values.h"
-#include "libnr/nr-point-fns.h"
-#include <2geom/geom.h>
+#include <2geom/line.h>
#include "line-snapper.h"
#include "snapped-line.h"
-#include <gtk/gtk.h>
+//#include <gtk/gtk.h>
#include "snap.h"
Inkscape::LineSnapper::LineSnapper(SnapManager *sm, Geom::Coord const d) : Snapper(sm, d)
std::vector<SPItem const *> const */*it*/,
std::vector<std::pair<Geom::Point, int> > */*unselected_nodes*/) const
{
- if (!(_snap_enabled && _snapmanager->snapprefs.getSnapFrom(t)) ) {
+ if (!(_snap_enabled && _snapmanager->snapprefs.getSnapFrom(t)) ) {
return;
}
// std::cout << " line through " << i->second << " with normal " << i->first;
g_assert(i->first != Geom::Point(0,0)); // we cannot project on an linesegment of zero length
- Geom::Point const p_proj = project_on_linesegment(p, p1, p2);
+ Geom::Point const p_proj = Geom::projection(p, Geom::Line(p1, p2));
Geom::Coord const dist = Geom::L2(p_proj - p);
//Store any line that's within snapping range
if (dist < getSnapperTolerance()) {
_addSnappedLine(sc, p_proj, dist, source_type, i->first, i->second);
+ // For any line that's within range, we will also look at it's "point on line" p1. For guides
+ // this point coincides with its origin; for grids this is of no use, but we cannot
+ // discern between grids and guides here
+ Geom::Coord const dist_p1 = Geom::L2(p1 - p);
+ if (dist_p1 < getSnapperTolerance()) {
+ _addSnappedLinesOrigin(sc, p1, dist_p1, source_type);
+ // Only relevant for guides; grids don't have an origin per line
+ // Therefore _addSnappedLinesOrigin() will only be implemented for guides
+ }
// std::cout << " -> distance = " << dist;
}
// std::cout << std::endl;
for (LineList::const_iterator i = lines.begin(); i != lines.end(); i++) {
if (Geom::L2(c.getDirection()) > 0) { // Can't do a constrained snap without a constraint
- /* Normal to the line we're trying to snap along */
- Geom::Point const n(Geom::rot90(Geom::unit_vector(c.getDirection())));
-
+ // constraint line
Geom::Point const point_on_line = c.hasPoint() ? c.getPoint() : p;
+ Geom::Line line1(point_on_line, point_on_line + c.getDirection());
- /* Constant term of the line we're trying to snap along */
- Geom::Coord const q0 = dot(n, point_on_line);
- /* Constant term of the grid or guide line */
- Geom::Coord const q1 = dot(i->first, i->second);
+ // grid/guide line
+ Geom::Point const p1 = i->second; // point at guide/grid line
+ Geom::Point const p2 = p1 + Geom::rot90(i->first); // 2nd point at guide/grid line
+ Geom::Line line2(p1, p2);
- /* 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, q0, i->first, q1, t_2geom);
- Geom::Point t(t_2geom);
+ Geom::OptCrossing inters = Geom::OptCrossing(); // empty by default
+ try
+ {
+ inters = Geom::intersection(line1, line2);
+ }
+ catch (Geom::InfiniteSolutions e)
+ {
+ // We're probably dealing with parallel lines, so snapping doesn't make any sense here
+ continue; // jump to the next iterator in the for-loop
+ }
- if (k == Geom::intersects) {
- const Geom::Coord dist = L2(t - p);
+ if (inters) {
+ Geom::Point t = line1.pointAt((*inters).ta);
+ const Geom::Coord dist = Geom::L2(t - p);
if (dist < getSnapperTolerance()) {
- // When doing a constrained snap, we're already at an intersection.
+ // 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
_addSnappedPoint(sc, t, dist, source_type);
+ // For any line that's within range, we will also look at it's "point on line" p1. For guides
+ // this point coincides with its origin; for grids this is of no use, but we cannot
+ // discern between grids and guides here
+ Geom::Coord const dist_p1 = Geom::L2(p1 - p);
+ if (dist_p1 < getSnapperTolerance()) {
+ _addSnappedLinesOrigin(sc, p1, dist_p1, source_type);
+ // Only relevant for guides; grids don't have an origin per line
+ // Therefore _addSnappedLinesOrigin() will only be implemented for guides
+ }
}
}
}
}
}
+// Will only be overridden in the guide-snapper class, because grid lines don't have an origin; the
+// grid-snapper classes will use this default empty method
+void Inkscape::LineSnapper::_addSnappedLinesOrigin(SnappedConstraints &/*sc*/, Geom::Point const /*origin*/, Geom::Coord const /*snapped_distance*/, SnapSourceType const &/*source_type*/) const
+{
+}
+
/*
Local Variables:
mode:c++