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diff --git a/src/snapper.h b/src/snapper.h
index 1801f309c807790fc701a77f55925080ff90489f..91784d3aefa539adf5751e1b58795a3b0f7e6dae 100644 (file)
--- a/src/snapper.h
+++ b/src/snapper.h
#include <map>
#include <list>
#include <boost/optional.hpp>
+#include <glib.h> // for g_assert
#include "snapped-point.h"
#include "snapped-line.h"
#include "snapped-curve.h"
#include "snap-preferences.h"
+#include "snap-candidate.h"
struct SnappedConstraints {
std::list<Inkscape::SnappedPoint> points;
namespace Inkscape
{
-
/// Parent for classes that can snap points to something
class Snapper
{
public:
- Snapper() {}
- Snapper(SnapManager *sm, ::Geom::Coord const t);
- virtual ~Snapper() {}
+ Snapper() {}
+ Snapper(SnapManager *sm, ::Geom::Coord const t);
+ virtual ~Snapper() {}
virtual Geom::Coord getSnapperTolerance() const = 0; //returns the tolerance of the snapper in screen pixels (i.e. independent of zoom)
virtual bool getSnapperAlwaysSnap() const = 0; //if true, then the snapper will always snap, regardless of its tolerance
// These four methods are only used for grids, for which snapping can be enabled individually
void setEnabled(bool s);
- void setSnapVisibleOnly(bool s);
+ void setSnapVisibleOnly(bool s);
bool getEnabled() const {return _snap_enabled;}
bool getSnapVisibleOnly() const {return _snap_visible_only;}
virtual void freeSnap(SnappedConstraints &/*sc*/,
- SnapPreferences::PointType const &/*t*/,
- Geom::Point const &/*p*/,
- SnapSourceType const &/*source_type*/,
- bool const &/*first_point*/,
+ Inkscape::SnapCandidatePoint const &/*p*/,
Geom::OptRect const &/*bbox_to_snap*/,
std::vector<SPItem const *> const */*it*/,
- std::vector<std::pair<Geom::Point, int> > */*unselected_nodes*/) const {};
-
- class ConstraintLine
+ std::vector<SnapCandidatePoint> */*unselected_nodes*/) const {};
+
+ // Class for storing the constraint for constrained snapping; can be
+ // - a line (infinite line with origin, running through _point pointing in _direction)
+ // - a direction (infinite line without origin, i.e. only a direction vector, stored in _direction)
+ // - a circle (_point denotes the center, _radius doesn't need an explanation, _direction contains
+ // the vector from the origin to the original untransformed point);
+ class SnapConstraint
{
- public:
- ConstraintLine(Geom::Point const &d) : _has_point(false), _direction(d) {}
- ConstraintLine(Geom::Point const &p, Geom::Point const &d) : _has_point(true), _point(p), _direction(d) {}
- ConstraintLine(Geom::Line const &l) : _has_point(true), _point(l.origin()), _direction(l.versor()) {}
+ private:
+ enum SnapConstraintType {LINE, DIRECTION, CIRCLE, UNDEFINED};
- bool hasPoint() const {
- return _has_point;
- }
+ public:
+ // Constructs a direction constraint, e.g. horizontal or vertical but without a specified point
+ SnapConstraint(Geom::Point const &d) : _direction(d), _type(DIRECTION) {}
+ // Constructs a linear constraint
+ SnapConstraint(Geom::Point const &p, Geom::Point const &d) : _point(p), _direction(d), _type(LINE) {}
+ SnapConstraint(Geom::Line const &l) : _point(l.origin()), _direction(l.versor()), _type(LINE) {}
+ // Constructs a circular constraint
+ SnapConstraint(Geom::Point const &p, Geom::Point const &d, Geom::Coord const &r) : _point(p), _direction(d), _radius(r), _type(CIRCLE) {}
+ // Undefined, or empty constraint
+ SnapConstraint() : _type(UNDEFINED) {}
+
+ bool hasPoint() const {return _type != DIRECTION && _type != UNDEFINED;}
Geom::Point getPoint() const {
+ g_assert(_type != DIRECTION && _type != UNDEFINED);
return _point;
}
return _direction;
}
- void setPoint(Geom::Point const &p) {
- _point = p;
- _has_point = true;
+ Geom::Coord getRadius() const {
+ g_assert(_type == CIRCLE);
+ return _radius;
}
- Geom::Point projection(Geom::Point const &p) const { // returns the projection of p on this constraintline
- Geom::Point const p1_on_cl = _has_point ? _point : p;
- Geom::Point const p2_on_cl = p1_on_cl + _direction;
- return Geom::projection(p, Geom::Line(p1_on_cl, p2_on_cl));
+ bool isCircular() const { return _type == CIRCLE; }
+ bool isLinear() const { return _type == LINE; }
+ bool isDirection() const { return _type == DIRECTION; }
+ bool isUndefined() const { return _type == UNDEFINED; }
+
+ Geom::Point projection(Geom::Point const &p) const { // returns the projection of p on this constraint
+ if (_type == CIRCLE) {
+ // project on to a circular constraint
+ Geom::Point v_orig = p - _point;
+ Geom::Coord l = Geom::L2(v_orig);
+ if (l > 0) {
+ return _point + _radius * v_orig/l; // Length of _direction is equal to the radius
+ } else {
+ // point to be projected is exactly at the center of the circle, so any point on the circle is a projection
+ return _point + Geom::Point(_radius, 0);
+ }
+ } else if (_type != UNDEFINED){
+ // project on to a linear constraint
+ Geom::Point const p1_on_cl = (_type == LINE) ? _point : p;
+ Geom::Point const p2_on_cl = p1_on_cl + _direction;
+ return Geom::projection(p, Geom::Line(p1_on_cl, p2_on_cl));
+ } else {
+ g_warning("Bug: trying to find the projection onto an undefined constraint");
+ return Geom::Point();
+ }
}
private:
-
- bool _has_point;
Geom::Point _point;
Geom::Point _direction;
+ Geom::Coord _radius;
+ SnapConstraintType _type;
};
virtual void constrainedSnap(SnappedConstraints &/*sc*/,
- SnapPreferences::PointType const &/*t*/,
- Geom::Point const &/*p*/,
- SnapSourceType const &/*source_type*/,
- bool const &/*first_point*/,
+ Inkscape::SnapCandidatePoint const &/*p*/,
Geom::OptRect const &/*bbox_to_snap*/,
- ConstraintLine const &/*c*/,
- std::vector<SPItem const *> const */*it*/) const {};
+ SnapConstraint const &/*c*/,
+ std::vector<SPItem const *> const */*it*/,
+ std::vector<SnapCandidatePoint> */*unselected_nodes*/) const {};
protected:
- SnapManager *_snapmanager;
+ SnapManager *_snapmanager;
- // This is only used for grids, for which snapping can be enabled individually
- bool _snap_enabled; ///< true if this snapper is enabled, otherwise false
- bool _snap_visible_only;
+ // This is only used for grids, for which snapping can be enabled individually
+ bool _snap_enabled; ///< true if this snapper is enabled, otherwise false
+ bool _snap_visible_only;
};
}