CrossingSet crossings_among(std::vector<Path> const &p) {
CrossingSet results(p.size(), Crossings());
if(p.empty()) return results;
SimpleCrosser cc;
std::vector<std::vector<unsigned> > cull = sweep_bounds(bounds(p));
for(unsigned i = 0; i < cull.size(); i++) {
Crossings res = self_crossings(p[i]);
for(unsigned k = 0; k < res.size(); k++) { res[k].a = res[k].b = i; }
merge_crossings(results[i], res, i);
flip_crossings(res);
merge_crossings(results[i], res, i);
for(unsigned jx = 0; jx < cull[i].size(); jx++) {
unsigned j = cull[i][jx];
Crossings res = cc.crossings(p[i], p[j]);
for(unsigned k = 0; k < res.size(); k++) { res[k].a = i; res[k].b = j; }
merge_crossings(results[i], res, i);
merge_crossings(results[j], res, j);
}
}
return results;
}
void SPShape::snappoints(std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs) const {
if (this->_curve == NULL) {
return;
}
Geom::PathVector const &pathv = this->_curve->get_pathvector();
if (pathv.empty()) {
return;
}
Geom::Affine const i2dt (this->i2dt_affine ());
if (snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_OBJECT_MIDPOINT)) {
Geom::OptRect bbox = this->desktopVisualBounds();
if (bbox) {
p.push_back(Inkscape::SnapCandidatePoint(bbox->midpoint(), Inkscape::SNAPSOURCE_OBJECT_MIDPOINT, Inkscape::SNAPTARGET_OBJECT_MIDPOINT));
}
}
for(Geom::PathVector::const_iterator path_it = pathv.begin(); path_it != pathv.end(); ++path_it) {
if (snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_NODE_CUSP)) {
// Add the first point of the path
p.push_back(Inkscape::SnapCandidatePoint(path_it->initialPoint() * i2dt, Inkscape::SNAPSOURCE_NODE_CUSP, Inkscape::SNAPTARGET_NODE_CUSP));
}
Geom::Path::const_iterator curve_it1 = path_it->begin(); // incoming curve
Geom::Path::const_iterator curve_it2 = ++(path_it->begin()); // outgoing curve
while (curve_it1 != path_it->end_default())
{
// For each path: consider midpoints of line segments for snapping
if (snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_LINE_MIDPOINT)) {
if (Geom::LineSegment const* line_segment = dynamic_cast<Geom::LineSegment const*>(&(*curve_it1))) {
p.push_back(Inkscape::SnapCandidatePoint(Geom::middle_point(*line_segment) * i2dt, Inkscape::SNAPSOURCE_LINE_MIDPOINT, Inkscape::SNAPTARGET_LINE_MIDPOINT));
}
}
if (curve_it2 == path_it->end_default()) { // Test will only pass for the last iteration of the while loop
if (snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_NODE_CUSP) && !path_it->closed()) {
// Add the last point of the path, but only for open paths
// (for closed paths the first and last point will coincide)
p.push_back(Inkscape::SnapCandidatePoint((*curve_it1).finalPoint() * i2dt, Inkscape::SNAPSOURCE_NODE_CUSP, Inkscape::SNAPTARGET_NODE_CUSP));
}
} else {
/* Test whether to add the node between curve_it1 and curve_it2.
* Loop to end_default (so only iterating through the stroked part); */
Geom::NodeType nodetype = Geom::get_nodetype(*curve_it1, *curve_it2);
bool c1 = snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_NODE_CUSP) && (nodetype == Geom::NODE_CUSP || nodetype == Geom::NODE_NONE);
bool c2 = snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_NODE_SMOOTH) && (nodetype == Geom::NODE_SMOOTH || nodetype == Geom::NODE_SYMM);
if (c1 || c2) {
Inkscape::SnapSourceType sst;
Inkscape::SnapTargetType stt;
switch (nodetype) {
case Geom::NODE_CUSP:
sst = Inkscape::SNAPSOURCE_NODE_CUSP;
stt = Inkscape::SNAPTARGET_NODE_CUSP;
break;
case Geom::NODE_SMOOTH:
case Geom::NODE_SYMM:
sst = Inkscape::SNAPSOURCE_NODE_SMOOTH;
stt = Inkscape::SNAPTARGET_NODE_SMOOTH;
break;
default:
sst = Inkscape::SNAPSOURCE_UNDEFINED;
stt = Inkscape::SNAPTARGET_UNDEFINED;
break;
}
p.push_back(Inkscape::SnapCandidatePoint(curve_it1->finalPoint() * i2dt, sst, stt));
}
}
++curve_it1;
++curve_it2;
}
// Find the internal intersections of each path and consider these for snapping
// (using "Method 1" as described in Inkscape::ObjectSnapper::_collectNodes())
if (snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_PATH_INTERSECTION) || snapprefs->isSourceSnappable(Inkscape::SNAPSOURCE_PATH_INTERSECTION)) {
Geom::Crossings cs;
try {
cs = self_crossings(*path_it); // This can be slow!
if (!cs.empty()) { // There might be multiple intersections...
for (Geom::Crossings::const_iterator i = cs.begin(); i != cs.end(); ++i) {
Geom::Point p_ix = (*path_it).pointAt((*i).ta);
p.push_back(Inkscape::SnapCandidatePoint(p_ix * i2dt, Inkscape::SNAPSOURCE_PATH_INTERSECTION, Inkscape::SNAPTARGET_PATH_INTERSECTION));
}
}
} catch (Geom::RangeError &e) {
// do nothing
// The exception could be Geom::InfiniteSolutions: then no snappoints should be added
}
}
}
}
