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diff --git a/src/snapper.h b/src/snapper.h
index 21e96b019e10820e87e25574c7a9ff5e4078f11d..91784d3aefa539adf5751e1b58795a3b0f7e6dae 100644 (file)
--- a/src/snapper.h
+++ b/src/snapper.h
*
* Authors:
* Carl Hetherington <inkscape@carlh.net>
+ * Diederik van Lierop <mail@diedenrezi.nl>
*
* Released under GNU GPL, read the file 'COPYING' for more information.
*/
#include <map>
#include <list>
-#include "libnr/nr-coord.h"
-#include "libnr/nr-point.h"
+#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;
+ std::list<Inkscape::SnappedLineSegment> lines;
+ std::list<Inkscape::SnappedLine> grid_lines;
+ std::list<Inkscape::SnappedLine> guide_lines;
+ std::list<Inkscape::SnappedCurve> curves;
+};
-struct SPNamedView;
+class SnapManager;
struct SPItem;
namespace Inkscape
{
-
/// Parent for classes that can snap points to something
class Snapper
{
public:
Snapper() {}
- Snapper(SPNamedView const *nv, ::NR::Coord const d);
+ Snapper(SnapManager *sm, ::Geom::Coord const t);
virtual ~Snapper() {}
- /// Point types to snap.
- typedef int PointType;
- static const PointType SNAP_POINT;
- static const PointType BBOX_POINT;
-
- typedef std::pair<PointType, NR::Point> PointWithType;
-
- void setSnapTo(PointType t, bool s);
- void setDistance(::NR::Coord d);
-
- bool getSnapTo(PointType t) const;
- ::NR::Coord getDistance() const;
+ 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
/**
* \return true if this Snapper will snap at least one kind of point.
*/
- virtual bool willSnapSomething() const {return (_enabled && _snap_to != 0);} // will likely be overridden by derived classes
-
+ virtual bool ThisSnapperMightSnap() const {return _snap_enabled;} // will likely be overridden by derived classes
+ // These four methods are only used for grids, for which snapping can be enabled individually
void setEnabled(bool s);
-
- SnappedPoint freeSnap(PointType t,
- NR::Point const &p,
- SPItem const *it) const;
-
- SnappedPoint freeSnap(PointType t,
- NR::Point const &p,
- std::list<SPItem const *> const &it) const;
-
- class ConstraintLine
+ void setSnapVisibleOnly(bool s);
+ bool getEnabled() const {return _snap_enabled;}
+ bool getSnapVisibleOnly() const {return _snap_visible_only;}
+
+ virtual void freeSnap(SnappedConstraints &/*sc*/,
+ Inkscape::SnapCandidatePoint const &/*p*/,
+ Geom::OptRect const &/*bbox_to_snap*/,
+ std::vector<SPItem const *> const */*it*/,
+ 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
{
+ private:
+ enum SnapConstraintType {LINE, DIRECTION, CIRCLE, UNDEFINED};
+
public:
- ConstraintLine(NR::Point const &d) : _has_point(false), _direction(d) {}
- ConstraintLine(NR::Point const &p, NR::Point const &d) : _has_point(true), _point(p), _direction(d) {}
+ // 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;
+ }
- bool hasPoint() const {
- return _has_point;
+ Geom::Point getDirection() const {
+ return _direction;
}
- NR::Point getPoint() const {
- return _point;
+ Geom::Coord getRadius() const {
+ g_assert(_type == CIRCLE);
+ return _radius;
}
- NR::Point getDirection() const {
- return _direction;
+ 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;
- NR::Point _point;
- NR::Point _direction;
+ private:
+ Geom::Point _point;
+ Geom::Point _direction;
+ Geom::Coord _radius;
+ SnapConstraintType _type;
};
- SnappedPoint constrainedSnap(PointType t,
- NR::Point const &p,
- ConstraintLine const &c,
- SPItem const *it) const;
+ virtual void constrainedSnap(SnappedConstraints &/*sc*/,
+ Inkscape::SnapCandidatePoint const &/*p*/,
+ Geom::OptRect const &/*bbox_to_snap*/,
+ SnapConstraint const &/*c*/,
+ std::vector<SPItem const *> const */*it*/,
+ std::vector<SnapCandidatePoint> */*unselected_nodes*/) const {};
- SnappedPoint constrainedSnap(PointType t,
- NR::Point const &p,
- ConstraintLine const &c,
- std::list<SPItem const *> const &it) const;
protected:
- SPNamedView const *_named_view;
- int _snap_to; ///< bitmap of point types that we will snap to
- bool _enabled; ///< true if this snapper is enabled, otherwise false
-
-private:
+ SnapManager *_snapmanager;
- /**
- * Try to snap a point to whatever this snapper is interested in. Any
- * snap that occurs will be to the nearest "interesting" thing (e.g. a
- * grid or guide line)
- *
- * \param p Point to snap (desktop coordinates).
- * \param it Items that should not be snapped to.
- * \return Snapped point.
- */
- virtual SnappedPoint _doFreeSnap(NR::Point const &p,
- std::list<SPItem const *> const &it) const = 0;
-
- /**
- * Try to snap a point to whatever this snapper is interested in, where
- * the snap point is constrained to lie along a specified vector from the
- * original point.
- *
- * \param p Point to snap (desktop coordinates).
- * \param c Vector to constrain the snap to.
- * \param it Items that should not be snapped to.
- * \return Snapped point.
- */
- virtual SnappedPoint _doConstrainedSnap(NR::Point const &p,
- ConstraintLine const &c,
- std::list<SPItem const *> const &it) const = 0;
-
- ::NR::Coord _distance; ///< snap distance (desktop coordinates)
+ // 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;
};
}