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diff --git a/src/snap.cpp b/src/snap.cpp
index 940d4c77208c6f17f898423baf692080a67892d0..2e38e4f146d9db8bc610ff049e10cb93e82ce35b 100644 (file)
--- a/src/snap.cpp
+++ b/src/snap.cpp
/**
* \file snap.cpp
- *
- * \brief Various snapping methods
+ * \brief SnapManager class.
*
* Authors:
* Lauris Kaplinski <lauris@kaplinski.com>
* Frank Felfe <innerspace@iname.com>
+ * Nathan Hurst <njh@njhurst.com>
* Carl Hetherington <inkscape@carlh.net>
+ * Diederik van Lierop <mail@diedenrezi.nl>
*
- * Copyright (C) 1999-2002 Authors
+ * Copyright (C) 2006-2007 Johan Engelen <johan@shouraizou.nl>
+ * Copyrigth (C) 2004 Nathan Hurst
+ * Copyright (C) 1999-2009 Authors
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
+#include <utility>
+
#include "sp-namedview.h"
#include "snap.h"
-#include <libnr/nr-point-fns.h>
-#include <libnr/nr-scale-ops.h>
-#include <libnr/nr-values.h>
+#include "snapped-line.h"
+#include "snapped-curve.h"
+
+#include "display/canvas-grid.h"
+#include "display/snap-indicator.h"
+
+#include "inkscape.h"
+#include "desktop.h"
+#include "sp-guide.h"
+#include "preferences.h"
+#include "event-context.h"
+using std::vector;
+
+/**
+ * Construct a SnapManager for a SPNamedView.
+ *
+ * \param v `Owning' SPNamedView.
+ */
-SnapManager::SnapperList SnapManager::getSnappers() const
+SnapManager::SnapManager(SPNamedView const *v) :
+ guide(this, 0),
+ object(this, 0),
+ snapprefs(),
+ _named_view(v)
+{
+}
+
+/**
+ * \brief Return a list of snappers
+ *
+ * Inkscape snaps to objects, grids, and guides. For each of these snap targets a
+ * separate class is used, which has been derived from the base Snapper class. The
+ * getSnappers() method returns a list of pointers to instances of this class. This
+ * list contains exactly one instance of the guide snapper and of the object snapper
+ * class, but any number of grid snappers (because each grid has its own snapper
+ * instance)
+ *
+ * \return List of snappers that we use.
+ */
+SnapManager::SnapperList
+SnapManager::getSnappers() const
{
SnapManager::SnapperList s;
- s.push_back(&grid);
s.push_back(&guide);
s.push_back(&object);
+
+ SnapManager::SnapperList gs = getGridSnappers();
+ s.splice(s.begin(), gs);
+
return s;
}
/**
- * \return true if one of the snappers will try to snap something.
+ * \brief Return a list of gridsnappers
+ *
+ * Each grid has its own instance of the snapper class. This way snapping can
+ * be enabled per grid individually. A list will be returned containing the
+ * pointers to these instances, but only for grids that are being displayed
+ * and for which snapping is enabled.
+ *
+ * \return List of gridsnappers that we use.
*/
-bool SnapManager::willSnapSomething() const
+SnapManager::SnapperList
+SnapManager::getGridSnappers() const
{
+ SnapperList s;
+
+ if (_desktop && _desktop->gridsEnabled() && snapprefs.getSnapToGrids()) {
+ for ( GSList const *l = _named_view->grids; l != NULL; l = l->next) {
+ Inkscape::CanvasGrid *grid = (Inkscape::CanvasGrid*) l->data;
+ s.push_back(grid->snapper);
+ }
+ }
+
+ return s;
+}
+
+/**
+ * \brief Return true if any snapping might occur, whether its to grids, guides or objects
+ *
+ * Each snapper instance handles its own snapping target, e.g. grids, guides or
+ * objects. This method iterates through all these snapper instances and returns
+ * true if any of the snappers might possible snap, considering only the relevant
+ * snapping preferences.
+ *
+ * \return true if one of the snappers will try to snap to something.
+ */
+
+bool SnapManager::someSnapperMightSnap() const
+{
+ if ( !snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally() ) {
+ return false;
+ }
+
SnapperList const s = getSnappers();
SnapperList::const_iterator i = s.begin();
- while (i != s.end() && (*i)->willSnapSomething() == false) {
+ while (i != s.end() && (*i)->ThisSnapperMightSnap() == false) {
i++;
}
return (i != s.end());
}
+/**
+ * \return true if one of the grids might be snapped to.
+ */
-/* FIXME: lots of cut-and-paste here. This needs some
-** functor voodoo to cut it all down a bit.
-*/
+bool SnapManager::gridSnapperMightSnap() const
+{
+ if ( !snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally() ) {
+ return false;
+ }
-Inkscape::SnappedPoint SnapManager::freeSnap(Inkscape::Snapper::PointType t,
- NR::Point const &p,
- SPItem const *it) const
+ SnapperList const s = getGridSnappers();
+ SnapperList::const_iterator i = s.begin();
+ while (i != s.end() && (*i)->ThisSnapperMightSnap() == false) {
+ i++;
+ }
+
+ return (i != s.end());
+}
+/**
+ * \brief Try to snap a point to grids, guides or objects.
+ *
+ * Try to snap a point to grids, guides or objects, in two degrees-of-freedom,
+ * i.e. snap in any direction on the two dimensional canvas to the nearest
+ * snap target. freeSnapReturnByRef() is equal in snapping behavior to
+ * freeSnap(), but the former returns the snapped point trough the referenced
+ * parameter p. This parameter p initially contains the position of the snap
+ * source and will we overwritten by the target position if snapping has occurred.
+ * This makes snapping transparent to the calling code. If this is not desired
+ * because either the calling code must know whether snapping has occurred, or
+ * because the original position should not be touched, then freeSnap() should be
+ * called instead.
+ *
+ * PS: SnapManager::setup() must have been called before calling this method,
+ * but only once for a set of points
+ *
+ * \param point_type Category of points to which the source point belongs: node, guide or bounding box
+ * \param p Current position of the snap source; will be overwritten by the position of the snap target if snapping has occurred
+ * \param source_type Detailed description of the source type, will be used by the snap indicator
+ * \param source_num Sequence number of the source point within the set of points that is to be snapped. Starting at zero
+ * \param bbox_to_snap Bounding box hulling the set of points, all from the same selection and having the same transformation
+ */
+
+void SnapManager::freeSnapReturnByRef(Inkscape::SnapPreferences::PointType point_type,
+ Geom::Point &p,
+ Inkscape::SnapSourceType const source_type,
+ long source_num,
+ Geom::OptRect const &bbox_to_snap) const
{
- std::list<SPItem const *> lit;
- lit.push_back(it);
- return freeSnap(t, p, lit);
+ //TODO: PointType and source_type are somewhat redundant; can't we get rid of the point_type parameter?
+ Inkscape::SnappedPoint const s = freeSnap(point_type, p, source_type, source_num, bbox_to_snap);
+ s.getPoint(p);
}
-Inkscape::SnappedPoint SnapManager::freeSnap(Inkscape::Snapper::PointType t,
- NR::Point const &p,
- std::list<SPItem const *> const &it) const
+/**
+ * \brief Try to snap a point to grids, guides or objects.
+ *
+ * Try to snap a point to grids, guides or objects, in two degrees-of-freedom,
+ * i.e. snap in any direction on the two dimensional canvas to the nearest
+ * snap target. freeSnap() is equal in snapping behavior to
+ * freeSnapReturnByRef(). Please read the comments of the latter for more details
+ *
+ * PS: SnapManager::setup() must have been called before calling this method,
+ * but only once for a set of points
+ *
+ * \param point_type Category of points to which the source point belongs: node, guide or bounding box
+ * \param p Current position of the snap source
+ * \param source_type Detailed description of the source type, will be used by the snap indicator
+ * \param source_num Sequence number of the source point within the set of points that is to be snapped. Starting at zero
+ * \param bbox_to_snap Bounding box hulling the set of points, all from the same selection and having the same transformation
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics
+ */
+
+
+Inkscape::SnappedPoint SnapManager::freeSnap(Inkscape::SnapPreferences::PointType point_type,
+ Geom::Point const &p,
+ Inkscape::SnapSourceType const &source_type,
+ long source_num,
+ Geom::OptRect const &bbox_to_snap) const
{
- Inkscape::SnappedPoint r(p, NR_HUGE);
+ if (!someSnapperMightSnap()) {
+ return Inkscape::SnappedPoint(p, source_type, 0, Inkscape::SNAPTARGET_UNDEFINED, NR_HUGE, 0, false, false);
+ }
+ std::vector<SPItem const *> *items_to_ignore;
+ if (_item_to_ignore) { // If we have only a single item to ignore
+ // then build a list containing this single item;
+ // This single-item list will prevail over any other _items_to_ignore list, should that exist
+ items_to_ignore = new std::vector<SPItem const *>;
+ items_to_ignore->push_back(_item_to_ignore);
+ } else {
+ items_to_ignore = _items_to_ignore;
+ }
+
+ SnappedConstraints sc;
SnapperList const snappers = getSnappers();
+
for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); i++) {
- Inkscape::SnappedPoint const s = (*i)->freeSnap(t, p, it);
- if (s.getDistance() < r.getDistance()) {
- r = s;
+ (*i)->freeSnap(sc, point_type, p, source_type, source_num, bbox_to_snap, items_to_ignore, _unselected_nodes);
+ }
+
+ if (_item_to_ignore) {
+ delete items_to_ignore;
+ }
+
+ return findBestSnap(p, source_type, sc, false);
+}
+
+/**
+ * \brief Snap to the closest multiple of a grid pitch
+ *
+ * When pasting, we would like to snap to the grid. Problem is that we don't know which
+ * nodes were aligned to the grid at the time of copying, so we don't know which nodes
+ * to snap. If we'd snap an unaligned node to the grid, previously aligned nodes would
+ * become unaligned. That's undesirable. Instead we will make sure that the offset
+ * between the source and its pasted copy is a multiple of the grid pitch. If the source
+ * was aligned, then the copy will therefore also be aligned.
+ *
+ * PS: Whether we really find a multiple also depends on the snapping range! Most users
+ * will have "always snap" enabled though, in which case a multiple will always be found.
+ * PS2: When multiple grids are present then the result will become ambiguous. There is no
+ * way to control to which grid this method will snap.
+ *
+ * \param t Vector that represents the offset of the pasted copy with respect to the original
+ * \return Offset vector after snapping to the closest multiple of a grid pitch
+ */
+
+Geom::Point SnapManager::multipleOfGridPitch(Geom::Point const &t) const
+{
+ if (!snapprefs.getSnapEnabledGlobally()) // No need to check for snapprefs.getSnapPostponedGlobally() here
+ return t;
+
+ if (_desktop && _desktop->gridsEnabled()) {
+ bool success = false;
+ Geom::Point nearest_multiple;
+ Geom::Coord nearest_distance = NR_HUGE;
+
+ // It will snap to the grid for which we find the closest snap. This might be a different
+ // grid than to which the objects were initially aligned. I don't see an easy way to fix
+ // this, so when using multiple grids one can get unexpected results
+
+ // Cannot use getGridSnappers() because we need both the grids AND their snappers
+ // Therefore we iterate through all grids manually
+ for (GSList const *l = _named_view->grids; l != NULL; l = l->next) {
+ Inkscape::CanvasGrid *grid = (Inkscape::CanvasGrid*) l->data;
+ const Inkscape::Snapper* snapper = grid->snapper;
+ if (snapper && snapper->ThisSnapperMightSnap()) {
+ // To find the nearest multiple of the grid pitch for a given translation t, we
+ // will use the grid snapper. Simply snapping the value t to the grid will do, but
+ // only if the origin of the grid is at (0,0). If it's not then compensate for this
+ // in the translation t
+ Geom::Point const t_offset = t + grid->origin;
+ SnappedConstraints sc;
+ // Only the first three parameters are being used for grid snappers
+ snapper->freeSnap(sc, Inkscape::SnapPreferences::SNAPPOINT_NODE, t_offset, Inkscape::SNAPSOURCE_UNDEFINED, 0, Geom::OptRect(), NULL, NULL);
+ // Find the best snap for this grid, including intersections of the grid-lines
+ Inkscape::SnappedPoint s = findBestSnap(t_offset, Inkscape::SNAPSOURCE_UNDEFINED, sc, false);
+ if (s.getSnapped() && (s.getSnapDistance() < nearest_distance)) {
+ // use getSnapDistance() instead of getWeightedDistance() here because the pointer's position
+ // doesn't tell us anything about which node to snap
+ success = true;
+ nearest_multiple = s.getPoint() - to_2geom(grid->origin);
+ nearest_distance = s.getSnapDistance();
+ }
+ }
}
+
+ if (success)
+ return nearest_multiple;
}
- return r;
+ return t;
}
+/**
+ * \brief Try to snap a point along a constraint line to grids, guides or objects.
+ *
+ * Try to snap a point to grids, guides or objects, in only one degree-of-freedom,
+ * i.e. snap in a specific direction on the two dimensional canvas to the nearest
+ * snap target.
+ *
+ * constrainedSnapReturnByRef() is equal in snapping behavior to
+ * constrainedSnap(), but the former returns the snapped point trough the referenced
+ * parameter p. This parameter p initially contains the position of the snap
+ * source and will we overwritten by the target position if snapping has occurred.
+ * This makes snapping transparent to the calling code. If this is not desired
+ * because either the calling code must know whether snapping has occurred, or
+ * because the original position should not be touched, then constrainedSnap() should
+ * be called instead.
+ *
+ * PS: SnapManager::setup() must have been called before calling this method,
+ * but only once for a set of points
+ *
+ * \param point_type Category of points to which the source point belongs: node, guide or bounding box
+ * \param p Current position of the snap source; will be overwritten by the position of the snap target if snapping has occurred
+ * \param source_type Detailed description of the source type, will be used by the snap indicator
+ * \param constraint The direction or line along which snapping must occur
+ * \param source_num Sequence number of the source point within the set of points that is to be snapped. Starting at zero
+ * \param bbox_to_snap Bounding box hulling the set of points, all from the same selection and having the same transformation
+ */
-Inkscape::SnappedPoint SnapManager::constrainedSnap(Inkscape::Snapper::PointType t,
- NR::Point const &p,
- NR::Point const &c,
- SPItem const *it) const
+void SnapManager::constrainedSnapReturnByRef(Inkscape::SnapPreferences::PointType point_type,
+ Geom::Point &p,
+ Inkscape::SnapSourceType const source_type,
+ Inkscape::Snapper::ConstraintLine const &constraint,
+ long source_num,
+ Geom::OptRect const &bbox_to_snap) const
{
- std::list<SPItem const *> lit;
- lit.push_back(it);
- return constrainedSnap(t, p, c, lit);
+ Inkscape::SnappedPoint const s = constrainedSnap(point_type, p, source_type, constraint, source_num, bbox_to_snap);
+ s.getPoint(p);
}
+/**
+ * \brief Try to snap a point along a constraint line to grids, guides or objects.
+ *
+ * Try to snap a point to grids, guides or objects, in only one degree-of-freedom,
+ * i.e. snap in a specific direction on the two dimensional canvas to the nearest
+ * snap target. constrainedSnap is equal in snapping behavior to
+ * constrainedSnapReturnByRef(). Please read the comments of the latter for more details.
+ *
+ * PS: SnapManager::setup() must have been called before calling this method,
+ * but only once for a set of points
+ *
+ * \param point_type Category of points to which the source point belongs: node, guide or bounding box
+ * \param p Current position of the snap source
+ * \param source_type Detailed description of the source type, will be used by the snap indicator
+ * \param constraint The direction or line along which snapping must occur
+ * \param source_num Sequence number of the source point within the set of points that is to be snapped. Starting at zero
+ * \param bbox_to_snap Bounding box hulling the set of points, all from the same selection and having the same transformation
+ */
-Inkscape::SnappedPoint SnapManager::constrainedSnap(Inkscape::Snapper::PointType t,
- NR::Point const &p,
- NR::Point const &c,
- std::list<SPItem const *> const &it) const
+Inkscape::SnappedPoint SnapManager::constrainedSnap(Inkscape::SnapPreferences::PointType point_type,
+ Geom::Point const &p,
+ Inkscape::SnapSourceType const &source_type,
+ Inkscape::Snapper::ConstraintLine const &constraint,
+ long source_num,
+ Geom::OptRect const &bbox_to_snap) const
{
- Inkscape::SnappedPoint r(p, NR_HUGE);
+ if (!someSnapperMightSnap()) {
+ return Inkscape::SnappedPoint(p, source_type, 0, Inkscape::SNAPTARGET_UNDEFINED, NR_HUGE, 0, false, false);
+ }
+ std::vector<SPItem const *> *items_to_ignore;
+ if (_item_to_ignore) { // If we have only a single item to ignore
+ // then build a list containing this single item;
+ // This single-item list will prevail over any other _items_to_ignore list, should that exist
+ items_to_ignore = new std::vector<SPItem const *>;
+ items_to_ignore->push_back(_item_to_ignore);
+ } else {
+ items_to_ignore = _items_to_ignore;
+ }
+
+
+ // First project the mouse pointer onto the constraint
+ Geom::Point pp = constraint.projection(p);
+ // Then try to snap the projected point
+
+ SnappedConstraints sc;
SnapperList const snappers = getSnappers();
for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); i++) {
- Inkscape::SnappedPoint const s = (*i)->constrainedSnap(t, p, c, it);
- if (s.getDistance() < r.getDistance()) {
- r = s;
- }
+ (*i)->constrainedSnap(sc, point_type, pp, source_type, source_num, bbox_to_snap, constraint, items_to_ignore);
}
- return r;
-}
+ if (_item_to_ignore) {
+ delete items_to_ignore;
+ }
+ return findBestSnap(pp, source_type, sc, true);
+}
-std::pair<NR::Point, bool> SnapManager::freeSnapTranslation(Inkscape::Snapper::PointType t,
- std::vector<NR::Point> const &p,
- std::list<SPItem const *> const &it,
- NR::Point const &tr) const
+/**
+ * \brief Try to snap a point of a guide to another guide or to a node
+ *
+ * Try to snap a point of a guide to another guide or to a node in two degrees-
+ * of-freedom, i.e. snap in any direction on the two dimensional canvas to the
+ * nearest snap target. This method is used when dragging or rotating a guide
+ *
+ * PS: SnapManager::setup() must have been called before calling this method,
+ *
+ * \param p Current position of the point on the guide that is to be snapped; will be overwritten by the position of the snap target if snapping has occurred
+ * \param guide_normal Vector normal to the guide line
+ */
+void SnapManager::guideFreeSnap(Geom::Point &p, Geom::Point const &guide_normal, SPGuideDragType drag_type) const
{
- if (willSnapSomething() == false) {
- return std::make_pair(tr, false);
+ if (!snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally()) {
+ return;
}
- NR::Point best_translation = tr;
- NR::Coord best_distance = NR_HUGE;
+ if (!(object.GuidesMightSnap() || snapprefs.getSnapToGuides())) {
+ return;
+ }
- for (std::vector<NR::Point>::const_iterator i = p.begin(); i != p.end(); i++) {
- /* Translated version of this point */
- NR::Point const q = *i + tr;
- /* Snap it */
- Inkscape::SnappedPoint s = freeSnap(t, q, it);
- if (s.getDistance() < NR_HUGE) {
- /* Resulting translation */
- NR::Point const r = s.getPoint() - *i;
- NR::Coord const d = NR::L2(r);
- if (d < best_distance) {
- best_distance = d;
- best_translation = r;
- }
- }
+ Inkscape::SnapSourceType source_type = Inkscape::SNAPSOURCE_GUIDE_ORIGIN;
+ if (drag_type == SP_DRAG_ROTATE) {
+ source_type = Inkscape::SNAPSOURCE_GUIDE;
+ }
+
+ // Snap to nodes
+ SnappedConstraints sc;
+ if (object.GuidesMightSnap()) {
+ object.guideFreeSnap(sc, p, guide_normal);
+ }
+
+ // Snap to guides & grid lines
+ SnapperList snappers = getGridSnappers();
+ snappers.push_back(&guide);
+ for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); i++) {
+ (*i)->freeSnap(sc, Inkscape::SnapPreferences::SNAPPOINT_GUIDE, p, source_type, 0, Geom::OptRect(), NULL, NULL);
}
- return std::make_pair(best_translation, best_distance < NR_HUGE);
+ // Snap to intersections of curves, but not to the curves themselves! (see _snapTranslatingGuideToNodes in object-snapper.cpp)
+ Inkscape::SnappedPoint const s = findBestSnap(p, source_type, sc, false, true);
+
+ s.getPoint(p);
}
+/**
+ * \brief Try to snap a point on a guide to the intersection with another guide or a path
+ *
+ * Try to snap a point on a guide to the intersection of that guide with another
+ * guide or with a path. The snapped point will lie somewhere on the guide-line,
+ * making this is a constrained snap, i.e. in only one degree-of-freedom.
+ * This method is used when dragging the origin of the guide along the guide itself.
+ *
+ * PS: SnapManager::setup() must have been called before calling this method,
+ *
+ * \param p Current position of the point on the guide that is to be snapped; will be overwritten by the position of the snap target if snapping has occurred
+ * \param guide_normal Vector normal to the guide line
+ */
+void SnapManager::guideConstrainedSnap(Geom::Point &p, SPGuide const &guideline) const
+{
+ if (!snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally()) {
+ return;
+ }
+
+ if (!(object.ThisSnapperMightSnap() || snapprefs.getSnapToGuides())) {
+ return;
+ }
+
+ Inkscape::SnapSourceType source_type = Inkscape::SNAPSOURCE_GUIDE_ORIGIN;
+
+ // Snap to nodes or paths
+ SnappedConstraints sc;
+ Inkscape::Snapper::ConstraintLine cl(guideline.point_on_line, Geom::rot90(guideline.normal_to_line));
+ if (object.ThisSnapperMightSnap()) {
+ object.constrainedSnap(sc, Inkscape::SnapPreferences::SNAPPOINT_GUIDE, p, source_type, 0, Geom::OptRect(), cl, NULL);
+ }
+
+ // Snap to guides & grid lines
+ SnapperList snappers = getGridSnappers();
+ snappers.push_back(&guide);
+ for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); i++) {
+ (*i)->constrainedSnap(sc, Inkscape::SnapPreferences::SNAPPOINT_GUIDE, p, source_type, 0, Geom::OptRect(), cl, NULL);
+ }
+
+ Inkscape::SnappedPoint const s = findBestSnap(p, source_type, sc, false);
+ s.getPoint(p);
+}
+
+/**
+ * \brief Method for snapping sets of points while they are being transformed
+ *
+ * Method for snapping sets of points while they are being transformed, when using
+ * for example the selector tool. This method is for internal use only, and should
+ * not have to be called directly. Use freeSnapTransalation(), constrainedSnapScale(),
+ * etc. instead.
+ *
+ * This is what is being done in this method: transform each point, find out whether
+ * a free snap or constrained snap is more appropriate, do the snapping, calculate
+ * some metrics to quantify the snap "distance", and see if it's better than the
+ * previous snap. Finally, the best ("nearest") snap from all these points is returned.
+ *
+ * \param type Category of points to which the source point belongs: node or bounding box.
+ * \param points Collection of points to snap (snap sources), at their untransformed position, all points undergoing the same transformation. Paired with an identifier of the type of the snap source.
+ * \param pointer Location of the mouse pointer at the time dragging started (i.e. when the selection was still untransformed).
+ * \param constrained true if the snap is constrained, e.g. for stretching or for purely horizontal translation.
+ * \param constraint The direction or line along which snapping must occur, if 'constrained' is true; otherwise undefined.
+ * \param transformation_type Type of transformation to apply to points before trying to snap them.
+ * \param transformation Description of the transformation; details depend on the type.
+ * \param origin Origin of the transformation, if applicable.
+ * \param dim Dimension to which the transformation applies, if applicable.
+ * \param uniform true if the transformation should be uniform; only applicable for stretching and scaling.
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics.
+ */
-std::pair<NR::Point, bool> SnapManager::constrainedSnapTranslation(Inkscape::Snapper::PointType t,
- std::vector<NR::Point> const &p,
- NR::Point const &c,
- std::list<SPItem const *> const &it,
- NR::Point const &tr) const
+Inkscape::SnappedPoint SnapManager::_snapTransformed(
+ Inkscape::SnapPreferences::PointType type,
+ std::vector<std::pair<Geom::Point, int> > const &points,
+ Geom::Point const &pointer,
+ bool constrained,
+ Inkscape::Snapper::ConstraintLine const &constraint,
+ Transformation transformation_type,
+ Geom::Point const &transformation,
+ Geom::Point const &origin,
+ Geom::Dim2 dim,
+ bool uniform) const
{
- if (willSnapSomething() == false) {
- return std::make_pair(tr, false);
+ /* We have a list of points, which we are proposing to transform in some way. We need to see
+ ** if any of these points, when transformed, snap to anything. If they do, we return the
+ ** appropriate transformation with `true'; otherwise we return the original scale with `false'.
+ */
+
+ /* Quick check to see if we have any snappers that are enabled
+ ** Also used to globally disable all snapping
+ */
+ if (someSnapperMightSnap() == false) {
+ return Inkscape::SnappedPoint();
}
- NR::Point best_translation = tr;
- NR::Coord best_distance = NR_HUGE;
+ std::vector<std::pair<Geom::Point, int> > transformed_points;
+ Geom::Rect bbox;
- for (std::vector<NR::Point>::const_iterator i = p.begin(); i != p.end(); i++) {
- /* Translated version of this point */
- NR::Point const q = *i + tr;
- /* Snap it */
- Inkscape::SnappedPoint s = constrainedSnap(t, q, c, it);
- if (s.getDistance() < NR_HUGE) {
- /* Resulting translation */
- NR::Point const r = s.getPoint() - *i;
- NR::Coord const d = NR::L2(r);
- if (d < best_distance) {
- best_distance = d;
- best_translation = r;
- }
+ for (std::vector<std::pair<Geom::Point, int> >::const_iterator i = points.begin(); i != points.end(); i++) {
+
+ /* Work out the transformed version of this point */
+ Geom::Point transformed = _transformPoint(*i, transformation_type, transformation, origin, dim, uniform);
+
+ // add the current transformed point to the box hulling all transformed points
+ if (i == points.begin()) {
+ bbox = Geom::Rect(transformed, transformed);
+ } else {
+ bbox.expandTo(transformed);
}
+
+ transformed_points.push_back(std::make_pair(transformed, (*i).second));
}
- return std::make_pair(best_translation, best_distance < NR_HUGE);
-}
+ /* The current best transformation */
+ Geom::Point best_transformation = transformation;
+ /* The current best metric for the best transformation; lower is better, NR_HUGE
+ ** means that we haven't snapped anything.
+ */
+ Geom::Point best_scale_metric(NR_HUGE, NR_HUGE);
+ Inkscape::SnappedPoint best_snapped_point;
+ g_assert(best_snapped_point.getAlwaysSnap() == false); // Check initialization of snapped point
+ g_assert(best_snapped_point.getAtIntersection() == false);
+ std::vector<std::pair<Geom::Point, int> >::const_iterator j = transformed_points.begin();
+ long source_num = 0;
+ // std::cout << std::endl;
+ for (std::vector<std::pair<Geom::Point, int> >::const_iterator i = points.begin(); i != points.end(); i++) {
+ /* Snap it */
+ Inkscape::SnappedPoint snapped_point;
+ Inkscape::Snapper::ConstraintLine dedicated_constraint = constraint;
+ Geom::Point const b = ((*i).first - origin); // vector to original point
+
+ if (constrained) {
+ if ((transformation_type == SCALE || transformation_type == STRETCH) && uniform) {
+ // When uniformly scaling, each point will have its own unique constraint line,
+ // running from the scaling origin to the original untransformed point. We will
+ // calculate that line here
+ dedicated_constraint = Inkscape::Snapper::ConstraintLine(origin, b);
+ } else if (transformation_type == STRETCH) { // when non-uniform stretching {
+ dedicated_constraint = Inkscape::Snapper::ConstraintLine((*i).first, component_vectors[dim]);
+ } else if (transformation_type == TRANSLATION) {
+ // When doing a constrained translation, all points will move in the same direction, i.e.
+ // either horizontally or vertically. The lines along which they move are therefore all
+ // parallel, but might not be colinear. Therefore we will have to set the point through
+ // which the constraint-line runs here, for each point individually.
+ dedicated_constraint.setPoint((*i).first);
+ } // else: leave the original constraint, e.g. for skewing
+ if (transformation_type == SCALE && !uniform) {
+ g_warning("Non-uniform constrained scaling is not supported!");
+ }
+ snapped_point = constrainedSnap(type, (*j).first, static_cast<Inkscape::SnapSourceType>((*j).second), dedicated_constraint, source_num, bbox);
+ } else {
+ bool const c1 = fabs(b[Geom::X]) < 1e-6;
+ bool const c2 = fabs(b[Geom::Y]) < 1e-6;
+ if (transformation_type == SCALE && (c1 || c2) && !(c1 && c2)) {
+ // When scaling, a point aligned either horizontally or vertically with the origin can only
+ // move in that specific direction; therefore it should only snap in that direction, otherwise
+ // we will get snapped points with an invalid transformation
+ dedicated_constraint = Inkscape::Snapper::ConstraintLine(origin, component_vectors[c1]);
+ snapped_point = constrainedSnap(type, (*j).first, static_cast<Inkscape::SnapSourceType>((*j).second), dedicated_constraint, source_num, bbox);
+ } else {
+ snapped_point = freeSnap(type, (*j).first, static_cast<Inkscape::SnapSourceType>((*j).second), source_num, bbox);
+ }
+ }
+ // std::cout << "dist = " << snapped_point.getSnapDistance() << std::endl;
+ snapped_point.setPointerDistance(Geom::L2(pointer - (*i).first));
+
+ Geom::Point result;
+ Geom::Point scale_metric(NR_HUGE, NR_HUGE);
+
+ if (snapped_point.getSnapped()) {
+ /* We snapped. Find the transformation that describes where the snapped point has
+ ** ended up, and also the metric for this transformation.
+ */
+ Geom::Point const a = (snapped_point.getPoint() - origin); // vector to snapped point
+ //Geom::Point const b = (*i - origin); // vector to original point
+
+ switch (transformation_type) {
+ case TRANSLATION:
+ result = snapped_point.getPoint() - (*i).first;
+ /* Consider the case in which 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 single grid
+ * line. If we prefer snapping to an intersection instead of to a single
+ * grid line, then we cannot use "metric = Geom::L2(result)". Therefore the
+ * snapped distance will be used as a metric. Please note that the snapped
+ * distance is defined as the distance to the nearest line of the intersection,
+ * and not to the intersection itself!
+ */
+ // Only for translations, the relevant metric will be the real snapped distance,
+ // so we don't have to do anything special here
+ break;
+ case SCALE:
+ {
+ result = Geom::Point(NR_HUGE, NR_HUGE);
+ // If this point *i is horizontally or vertically aligned with
+ // the origin of the scaling, then it will scale purely in X or Y
+ // We can therefore only calculate the scaling in this direction
+ // and the scaling factor for the other direction should remain
+ // untouched (unless scaling is uniform ofcourse)
+ for (int index = 0; index < 2; index++) {
+ if (fabs(b[index]) > 1e-6) { // if SCALING CAN occur in this direction
+ if (fabs(fabs(a[index]/b[index]) - fabs(transformation[index])) > 1e-12) { // if SNAPPING DID occur in this direction
+ result[index] = a[index] / b[index]; // then calculate it!
+ }
+ // we might leave result[1-index] = NR_HUGE
+ // if scaling didn't occur in the other direction
+ }
+ }
+ // Compare the resulting scaling with the desired scaling
+ scale_metric = result - transformation; // One or both of its components might be NR_HUGE
+ break;
+ }
+ case STRETCH:
+ result = Geom::Point(NR_HUGE, NR_HUGE);
+ if (fabs(b[dim]) > 1e-6) { // if STRETCHING will occur for this point
+ result[dim] = a[dim] / b[dim];
+ result[1-dim] = uniform ? result[dim] : 1;
+ } else { // STRETCHING might occur for this point, but only when the stretching is uniform
+ if (uniform && fabs(b[1-dim]) > 1e-6) {
+ result[1-dim] = a[1-dim] / b[1-dim];
+ result[dim] = result[1-dim];
+ }
+ }
+ // Store the metric for this transformation as a virtual distance
+ snapped_point.setSnapDistance(std::abs(result[dim] - transformation[dim]));
+ snapped_point.setSecondSnapDistance(NR_HUGE);
+ break;
+ case SKEW:
+ result[0] = (snapped_point.getPoint()[dim] - ((*i).first)[dim]) / (((*i).first)[1 - dim] - origin[1 - dim]); // skew factor
+ result[1] = transformation[1]; // scale factor
+ // Store the metric for this transformation as a virtual distance
+ snapped_point.setSnapDistance(std::abs(result[0] - transformation[0]));
+ snapped_point.setSecondSnapDistance(NR_HUGE);
+ break;
+ default:
+ g_assert_not_reached();
+ }
+ // When scaling, we're considering the best transformation in each direction separately. We will have a metric in each
+ // direction, whereas for all other transformation we only a single one-dimensional metric. That's why we need to handle
+ // the scaling metric differently
+ if (transformation_type == SCALE) {
+ for (int index = 0; index < 2; index++) {
+ if (fabs(scale_metric[index]) < fabs(best_scale_metric[index])) {
+ best_transformation[index] = result[index];
+ best_scale_metric[index] = fabs(scale_metric[index]);
+ // When scaling, we're considering the best transformation in each direction separately
+ // Therefore two different snapped points might together make a single best transformation
+ // We will however return only a single snapped point (e.g. to display the snapping indicator)
+ best_snapped_point = snapped_point;
+ // std::cout << "SEL ";
+ } // else { std::cout << " ";}
+ }
+ if (uniform) {
+ if (best_scale_metric[0] < best_scale_metric[1]) {
+ best_transformation[1] = best_transformation[0];
+ best_scale_metric[1] = best_scale_metric[0];
+ } else {
+ best_transformation[0] = best_transformation[1];
+ best_scale_metric[0] = best_scale_metric[1];
+ }
+ }
+ } else { // For all transformations other than scaling
+ if (best_snapped_point.isOtherSnapBetter(snapped_point, true)) {
+ best_transformation = result;
+ best_snapped_point = snapped_point;
+ }
+ }
+ }
+
+ j++;
+ source_num++;
+ }
+
+ Geom::Coord best_metric;
+ if (transformation_type == SCALE) {
+ // When scaling, don't ever exit with one of scaling components set to NR_HUGE
+ for (int index = 0; index < 2; index++) {
+ if (best_transformation[index] == NR_HUGE) {
+ if (uniform && best_transformation[1-index] < NR_HUGE) {
+ best_transformation[index] = best_transformation[1-index];
+ } else {
+ best_transformation[index] = transformation[index];
+ }
+ }
+ }
+ best_metric = std::min(best_scale_metric[0], best_scale_metric[1]);
+ } else { // For all transformations other than scaling
+ best_metric = best_snapped_point.getSnapDistance();
+ }
+
+ best_snapped_point.setTransformation(best_transformation);
+ // Using " < 1e6" instead of " < NR_HUGE" for catching some rounding errors
+ // These rounding errors might be caused by NRRects, see bug #1584301
+ best_snapped_point.setSnapDistance(best_metric < 1e6 ? best_metric : NR_HUGE);
+ return best_snapped_point;
+}
-/// Minimal distance to norm before point is considered for snap.
-static const double MIN_DIST_NORM = 1.0;
/**
- * Try to snap \a req in one dimension.
+ * \brief Apply a translation to a set of points and try to snap freely in 2 degrees-of-freedom
*
- * \param nv NamedView to use.
- * \param req Point to snap; updated to the snapped point if a snap occurred.
- * \param dim Dimension to snap in.
- * \return Distance to the snap point along the \a dim axis, or \c NR_HUGE
- * if no snap occurred.
+ * \param point_type Category of points to which the source point belongs: node or bounding box.
+ * \param p Collection of points to snap (snap sources), at their untransformed position, all points undergoing the same transformation. Paired with an identifier of the type of the snap source.
+ * \param pointer Location of the mouse pointer at the time dragging started (i.e. when the selection was still untransformed).
+ * \param tr Proposed translation; the final translation can only be calculated after snapping has occurred
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics.
*/
-NR::Coord namedview_dim_snap(SPNamedView const *nv, Inkscape::Snapper::PointType t, NR::Point &req,
- NR::Dim2 const dim, SPItem const *it)
-{
- return namedview_vector_snap(nv, t, req, component_vectors[dim], it);
-}
-NR::Coord namedview_dim_snap(SPNamedView const *nv, Inkscape::Snapper::PointType t, NR::Point &req,
- NR::Dim2 const dim, std::list<SPItem const *> const &it)
+Inkscape::SnappedPoint SnapManager::freeSnapTranslation(Inkscape::SnapPreferences::PointType point_type,
+ std::vector<std::pair<Geom::Point, int> > const &p,
+ Geom::Point const &pointer,
+ Geom::Point const &tr) const
{
- return namedview_vector_snap(nv, t, req, component_vectors[dim], it);
+ if (p.size() == 1) {
+ _displaySnapsource(point_type, std::make_pair(_transformPoint(p.at(0), TRANSLATION, tr, Geom::Point(0,0), Geom::X, false), (p.at(0)).second));
+ }
+
+ return _snapTransformed(point_type, p, pointer, false, Geom::Point(0,0), TRANSLATION, tr, Geom::Point(0,0), Geom::X, false);
}
+/**
+ * \brief Apply a translation to a set of points and try to snap along a constraint
+ *
+ * \param point_type Category of points to which the source point belongs: node or bounding box.
+ * \param p Collection of points to snap (snap sources), at their untransformed position, all points undergoing the same transformation. Paired with an identifier of the type of the snap source.
+ * \param pointer Location of the mouse pointer at the time dragging started (i.e. when the selection was still untransformed).
+ * \param constraint The direction or line along which snapping must occur.
+ * \param tr Proposed translation; the final translation can only be calculated after snapping has occurred.
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics.
+ */
-NR::Coord namedview_vector_snap(SPNamedView const *nv, Inkscape::Snapper::PointType t,
- NR::Point &req, NR::Point const &d,
- SPItem const *it)
+Inkscape::SnappedPoint SnapManager::constrainedSnapTranslation(Inkscape::SnapPreferences::PointType point_type,
+ std::vector<std::pair<Geom::Point, int> > const &p,
+ Geom::Point const &pointer,
+ Inkscape::Snapper::ConstraintLine const &constraint,
+ Geom::Point const &tr) const
{
- std::list<SPItem const *> lit;
- lit.push_back(it);
- return namedview_vector_snap(nv, t, req, d, lit);
+ if (p.size() == 1) {
+ _displaySnapsource(point_type, std::make_pair(_transformPoint(p.at(0), TRANSLATION, tr, Geom::Point(0,0), Geom::X, false), (p.at(0)).second));
+ }
+
+ return _snapTransformed(point_type, p, pointer, true, constraint, TRANSLATION, tr, Geom::Point(0,0), Geom::X, false);
}
+
/**
- * Look for snap point along the line described by the point \a req
- * and the direction vector \a d.
- * Modifies req to the snap point, if one is found.
- * \return The distance from \a req to the snap point along the vector \a d,
- * or \c NR_HUGE if no snap point was found.
+ * \brief Apply a scaling to a set of points and try to snap freely in 2 degrees-of-freedom
*
- * \pre d \81â\89\81 (0, 0).
+ * \param point_type Category of points to which the source point belongs: node or bounding box.
+ * \param p Collection of points to snap (snap sources), at their untransformed position, all points undergoing the same transformation. Paired with an identifier of the type of the snap source.
+ * \param pointer Location of the mouse pointer at the time dragging started (i.e. when the selection was still untransformed).
+ * \param s Proposed scaling; the final scaling can only be calculated after snapping has occurred
+ * \param o Origin of the scaling
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics.
*/
-NR::Coord namedview_vector_snap(SPNamedView const *nv, Inkscape::Snapper::PointType t,
- NR::Point &req, NR::Point const &d,
- std::list<SPItem const *> const &it)
-{
- g_assert(nv != NULL);
- g_assert(SP_IS_NAMEDVIEW(nv));
- SnapManager::SnapperList const snappers = nv->snap_manager.getSnappers();
-
- NR::Coord best = NR_HUGE;
- for (SnapManager::SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); i++) {
- Inkscape::SnappedPoint const s = (*i)->constrainedSnap(t, req, d, it);
- if (s.getDistance() < best) {
- req = s.getPoint();
- best = s.getDistance();
- }
+Inkscape::SnappedPoint SnapManager::freeSnapScale(Inkscape::SnapPreferences::PointType point_type,
+ std::vector<std::pair<Geom::Point, int> > const &p,
+ Geom::Point const &pointer,
+ Geom::Scale const &s,
+ Geom::Point const &o) const
+{
+ if (p.size() == 1) {
+ _displaySnapsource(point_type, std::make_pair(_transformPoint(p.at(0), SCALE, Geom::Point(s[Geom::X], s[Geom::Y]), o, Geom::X, false), (p.at(0)).second));
}
- return best;
+ return _snapTransformed(point_type, p, pointer, false, Geom::Point(0,0), SCALE, Geom::Point(s[Geom::X], s[Geom::Y]), o, Geom::X, false);
}
-/*
- * functions for lists of points
+/**
+ * \brief Apply a scaling to a set of points and snap such that the aspect ratio of the selection is preserved
*
- * All functions take a list of NR::Point and parameter indicating the proposed transformation.
- * They return the updated transformation parameter.
+ * \param point_type Category of points to which the source point belongs: node or bounding box.
+ * \param p Collection of points to snap (snap sources), at their untransformed position, all points undergoing the same transformation. Paired with an identifier of the type of the snap source.
+ * \param pointer Location of the mouse pointer at the time dragging started (i.e. when the selection was still untransformed).
+ * \param s Proposed scaling; the final scaling can only be calculated after snapping has occurred
+ * \param o Origin of the scaling
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics.
*/
+Inkscape::SnappedPoint SnapManager::constrainedSnapScale(Inkscape::SnapPreferences::PointType point_type,
+ std::vector<std::pair<Geom::Point, int> > const &p,
+ Geom::Point const &pointer,
+ Geom::Scale const &s,
+ Geom::Point const &o) const
+{
+ // When constrained scaling, only uniform scaling is supported.
+ if (p.size() == 1) {
+ _displaySnapsource(point_type, std::make_pair(_transformPoint(p.at(0), SCALE, Geom::Point(s[Geom::X], s[Geom::Y]), o, Geom::X, true), (p.at(0)).second));
+ }
+
+ return _snapTransformed(point_type, p, pointer, true, Geom::Point(0,0), SCALE, Geom::Point(s[Geom::X], s[Geom::Y]), o, Geom::X, true);
+}
+
/**
- * Snap list of points in two dimensions.
+ * \brief Apply a stretch to a set of points and snap such that the direction of the stretch is preserved
+ *
+ * \param point_type Category of points to which the source point belongs: node or bounding box.
+ * \param p Collection of points to snap (snap sources), at their untransformed position, all points undergoing the same transformation. Paired with an identifier of the type of the snap source.
+ * \param pointer Location of the mouse pointer at the time dragging started (i.e. when the selection was still untransformed).
+ * \param s Proposed stretch; the final stretch can only be calculated after snapping has occurred
+ * \param o Origin of the stretching
+ * \param d Dimension in which to apply proposed stretch.
+ * \param u true if the stretch should be uniform (i.e. to be applied equally in both dimensions)
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics.
*/
-std::pair<double, bool> namedview_vector_snap_list(SPNamedView const *nv, Inkscape::Snapper::PointType t,
- const std::vector<NR::Point> &p, NR::Point const &norm,
- NR::scale const &s, std::list<SPItem const *> const &it)
+
+Inkscape::SnappedPoint SnapManager::constrainedSnapStretch(Inkscape::SnapPreferences::PointType point_type,
+ std::vector<std::pair<Geom::Point, int> > const &p,
+ Geom::Point const &pointer,
+ Geom::Coord const &s,
+ Geom::Point const &o,
+ Geom::Dim2 d,
+ bool u) const
{
- using NR::X;
- using NR::Y;
-
- SnapManager const &m = nv->snap_manager;
-
- if (m.willSnapSomething() == false) {
- return std::make_pair(s[X], false);
- }
-
- NR::Coord dist = NR_HUGE;
- double ratio = fabs(s[X]);
- for (std::vector<NR::Point>::const_iterator i = p.begin(); i != p.end(); i++) {
- NR::Point const &q = *i;
- NR::Point check = ( q - norm ) * s + norm;
- if (NR::LInfty( q - norm ) > MIN_DIST_NORM) {
- NR::Coord d = namedview_vector_snap(nv, t, check, check - norm, it);
- if (d < dist) {
- dist = d;
- NR::Dim2 const dominant = ( ( fabs( q[X] - norm[X] ) >
- fabs( q[Y] - norm[Y] ) )
- ? X
- : Y );
- ratio = ( ( check[dominant] - norm[dominant] )
- / ( q[dominant] - norm[dominant] ) );
- }
- }
+ if (p.size() == 1) {
+ _displaySnapsource(point_type, std::make_pair(_transformPoint(p.at(0), STRETCH, Geom::Point(s, s), o, d, u), (p.at(0)).second));
}
- return std::make_pair(ratio, dist < NR_HUGE);
+ return _snapTransformed(point_type, p, pointer, true, Geom::Point(0,0), STRETCH, Geom::Point(s, s), o, d, u);
}
+/**
+ * \brief Apply a skew to a set of points and snap such that the direction of the skew is preserved
+ *
+ * \param point_type Category of points to which the source point belongs: node or bounding box.
+ * \param p Collection of points to snap (snap sources), at their untransformed position, all points undergoing the same transformation. Paired with an identifier of the type of the snap source.
+ * \param pointer Location of the mouse pointer at the time dragging started (i.e. when the selection was still untransformed).
+ * \param constraint The direction or line along which snapping must occur.
+ * \param s Proposed skew; the final skew can only be calculated after snapping has occurred
+ * \param o Origin of the proposed skew
+ * \param d Dimension in which to apply proposed skew.
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics.
+ */
+
+Inkscape::SnappedPoint SnapManager::constrainedSnapSkew(Inkscape::SnapPreferences::PointType point_type,
+ std::vector<std::pair<Geom::Point, int> > const &p,
+ Geom::Point const &pointer,
+ Inkscape::Snapper::ConstraintLine const &constraint,
+ Geom::Point const &s,
+ Geom::Point const &o,
+ Geom::Dim2 d) const
+{
+ // "s" contains skew factor in s[0], and scale factor in s[1]
+
+ // Snapping the nodes of the bounding box of a selection that is being transformed, will only work if
+ // the transformation of the bounding box is equal to the transformation of the individual nodes. This is
+ // NOT the case for example when rotating or skewing. The bounding box itself cannot possibly rotate or skew,
+ // so it's corners have a different transformation. The snappers cannot handle this, therefore snapping
+ // of bounding boxes is not allowed here.
+ g_assert(!(point_type & Inkscape::SnapPreferences::SNAPPOINT_BBOX));
+
+ if (p.size() == 1) {
+ _displaySnapsource(point_type, std::make_pair(_transformPoint(p.at(0), SKEW, s, o, d, false), (p.at(0)).second));
+ }
+
+ return _snapTransformed(point_type, p, pointer, true, constraint, SKEW, s, o, d, false);
+}
/**
- * Try to snap points in \a p after they have been scaled by \a sx with respect to
- * the origin \a norm. The best snap is the one that changes the scale least.
+ * \brief Given a set of possible snap targets, find the best target (which is not necessarily
+ * also the nearest target), and show the snap indicator if requested
*
- * \return Pair containing snapped scale and a flag which is true if a snap was made.
+ * \param p Current position of the snap source
+ * \param source_type Detailed description of the source type, will be used by the snap indicator
+ * \param sc A structure holding all snap targets that have been found so far
+ * \param constrained True if the snap is constrained, e.g. for stretching or for purely horizontal translation.
+ * \param noCurves If true, then do consider snapping to intersections of curves, but not to the curves themself
+ * \return An instance of the SnappedPoint class, which holds data on the snap source, snap target, and various metrics
*/
-std::pair<double, bool> namedview_dim_snap_list_scale(SPNamedView const *nv, Inkscape::Snapper::PointType t,
- const std::vector<NR::Point> &p, NR::Point const &norm,
- double const sx, NR::Dim2 dim,
- std::list<const SPItem *> const &it)
+
+Inkscape::SnappedPoint SnapManager::findBestSnap(Geom::Point const &p,
+ Inkscape::SnapSourceType const source_type,
+ SnappedConstraints &sc,
+ bool constrained,
+ bool noCurves) const
{
- SnapManager const &m = nv->snap_manager;
- if (m.willSnapSomething() == false) {
- return std::make_pair(sx, false);
+
+ /*
+ std::cout << "Type and number of snapped constraints: " << std::endl;
+ std::cout << " Points : " << sc.points.size() << std::endl;
+ std::cout << " Lines : " << sc.lines.size() << std::endl;
+ std::cout << " Grid lines : " << sc.grid_lines.size()<< std::endl;
+ std::cout << " Guide lines : " << sc.guide_lines.size()<< std::endl;
+ std::cout << " Curves : " << sc.curves.size()<< std::endl;
+ */
+
+ // Store all snappoints
+ std::list<Inkscape::SnappedPoint> sp_list;
+
+ // search for the closest snapped point
+ Inkscape::SnappedPoint closestPoint;
+ if (getClosestSP(sc.points, closestPoint)) {
+ sp_list.push_back(closestPoint);
+ }
+
+ // search for the closest snapped curve
+ if (!noCurves) {
+ Inkscape::SnappedCurve closestCurve;
+ if (getClosestCurve(sc.curves, closestCurve)) {
+ sp_list.push_back(Inkscape::SnappedPoint(closestCurve));
+ }
+ }
+
+ if (snapprefs.getSnapIntersectionCS()) {
+ // search for the closest snapped intersection of curves
+ Inkscape::SnappedPoint closestCurvesIntersection;
+ if (getClosestIntersectionCS(sc.curves, p, closestCurvesIntersection, _desktop->dt2doc())) {
+ closestCurvesIntersection.setSource(source_type);
+ sp_list.push_back(closestCurvesIntersection);
+ }
}
- g_assert(dim < 2);
+ // search for the closest snapped grid line
+ Inkscape::SnappedLine closestGridLine;
+ if (getClosestSL(sc.grid_lines, closestGridLine)) {
+ sp_list.push_back(Inkscape::SnappedPoint(closestGridLine));
+ }
- NR::Coord dist = NR_HUGE;
- double scale = sx;
+ // search for the closest snapped guide line
+ Inkscape::SnappedLine closestGuideLine;
+ if (getClosestSL(sc.guide_lines, closestGuideLine)) {
+ sp_list.push_back(Inkscape::SnappedPoint(closestGuideLine));
+ }
- for (std::vector<NR::Point>::const_iterator i = p.begin(); i != p.end(); i++) {
- NR::Point q = *i;
- NR::Point check = q;
+ // When freely snapping to a grid/guide/path, only one degree of freedom is eliminated
+ // Therefore we will try get fully constrained by finding an intersection with another grid/guide/path
+
+ // When doing a constrained snap however, we're already at an intersection of the constrained line and
+ // the grid/guide/path we're snapping to. This snappoint is therefore fully constrained, so there's
+ // no need to look for additional intersections
+ if (!constrained) {
+ // search for the closest snapped intersection of grid lines
+ Inkscape::SnappedPoint closestGridPoint;
+ if (getClosestIntersectionSL(sc.grid_lines, closestGridPoint)) {
+ closestGridPoint.setSource(source_type);
+ closestGridPoint.setTarget(Inkscape::SNAPTARGET_GRID_INTERSECTION);
+ sp_list.push_back(closestGridPoint);
+ }
- /* Scaled version of the point we are looking at */
- check[dim] = (sx * (q - norm) + norm)[dim];
+ // search for the closest snapped intersection of guide lines
+ Inkscape::SnappedPoint closestGuidePoint;
+ if (getClosestIntersectionSL(sc.guide_lines, closestGuidePoint)) {
+ closestGuidePoint.setSource(source_type);
+ closestGuidePoint.setTarget(Inkscape::SNAPTARGET_GUIDE_INTERSECTION);
+ sp_list.push_back(closestGuidePoint);
+ }
- if (fabs (q[dim] - norm[dim]) > MIN_DIST_NORM) {
- /* Snap this point */
- const NR::Coord d = namedview_dim_snap (nv, t, check, dim, it);
- /* Work out the resulting scale factor */
- double snapped_scale = (check[dim] - norm[dim]) / (q[dim] - norm[dim]);
+ // search for the closest snapped intersection of grid with guide lines
+ if (snapprefs.getSnapIntersectionGG()) {
+ Inkscape::SnappedPoint closestGridGuidePoint;
+ if (getClosestIntersectionSL(sc.grid_lines, sc.guide_lines, closestGridGuidePoint)) {
+ closestGridGuidePoint.setSource(source_type);
+ closestGridGuidePoint.setTarget(Inkscape::SNAPTARGET_GRID_GUIDE_INTERSECTION);
+ sp_list.push_back(closestGridGuidePoint);
+ }
+ }
+ }
- if (dist == NR_HUGE || fabs(snapped_scale - sx) < fabs(scale - sx)) {
- /* This is either the first point, or the snapped scale
- ** is the closest yet to the original.
- */
- scale = snapped_scale;
- dist = d;
+ // now let's see which snapped point gets a thumbs up
+ Inkscape::SnappedPoint bestSnappedPoint = Inkscape::SnappedPoint(p, Inkscape::SNAPSOURCE_UNDEFINED, 0, Inkscape::SNAPTARGET_UNDEFINED, NR_HUGE, 0, false, false);
+ // std::cout << "Finding the best snap..." << std::endl;
+ for (std::list<Inkscape::SnappedPoint>::const_iterator i = sp_list.begin(); i != sp_list.end(); i++) {
+ // first find out if this snapped point is within snapping range
+ // std::cout << "sp = " << from_2geom((*i).getPoint());
+ if ((*i).getSnapDistance() <= (*i).getTolerance()) {
+ // if it's the first point, or if it is closer than the best snapped point so far
+ if (i == sp_list.begin() || bestSnappedPoint.isOtherSnapBetter(*i, false)) {
+ // then prefer this point over the previous one
+ bestSnappedPoint = *i;
}
}
+ // std::cout << std::endl;
}
- return std::make_pair(scale, dist < NR_HUGE);
+ // Update the snap indicator, if requested
+ if (_snapindicator) {
+ if (bestSnappedPoint.getSnapped()) {
+ _desktop->snapindicator->set_new_snaptarget(bestSnappedPoint);
+ } else {
+ _desktop->snapindicator->remove_snaptarget();
+ }
+ }
+
+ // std::cout << "findBestSnap = " << bestSnappedPoint.getPoint() << " | dist = " << bestSnappedPoint.getSnapDistance() << std::endl;
+ return bestSnappedPoint;
}
/**
- * Try to snap points after they have been skewed.
+ * \brief Prepare the snap manager for the actual snapping, which includes building a list of snap targets
+ * to ignore and toggling the snap indicator
+ *
+ * There are two overloaded setup() methods, of which this one only allows for a single item to be ignored
+ * whereas the other one will take a list of items to ignore
+ *
+ * \param desktop Reference to the desktop to which this snap manager is attached
+ * \param snapindicator If true then a snap indicator will be displayed automatically (when enabled in the preferences)
+ * \param item_to_ignore This item will not be snapped to, e.g. the item that is currently being dragged. This avoids "self-snapping"
+ * \param unselected_nodes Stationary nodes of the path that is currently being edited in the node tool and
+ * that can be snapped too. Nodes not in this list will not be snapped to, to avoid "self-snapping". Of each
+ * unselected node both the position (Geom::Point) and the type (Inkscape::SnapTargetType) will be stored
+ * \param guide_to_ignore Guide that is currently being dragged and should not be snapped to
*/
-double namedview_dim_snap_list_skew(SPNamedView const *nv, Inkscape::Snapper::PointType t,
- const std::vector<NR::Point> &p, NR::Point const &norm,
- double const sx, NR::Dim2 const dim)
+
+void SnapManager::setup(SPDesktop const *desktop,
+ bool snapindicator,
+ SPItem const *item_to_ignore,
+ std::vector<std::pair<Geom::Point, int> > *unselected_nodes,
+ SPGuide *guide_to_ignore)
{
- SnapManager const &m = nv->snap_manager;
+ g_assert(desktop != NULL);
+ _item_to_ignore = item_to_ignore;
+ _items_to_ignore = NULL;
+ _desktop = desktop;
+ _snapindicator = snapindicator;
+ _unselected_nodes = unselected_nodes;
+ _guide_to_ignore = guide_to_ignore;
+}
- if (m.willSnapSomething() == false) {
- return sx;
- }
+/**
+ * \brief Prepare the snap manager for the actual snapping, which includes building a list of snap targets
+ * to ignore and toggling the snap indicator
+ *
+ * There are two overloaded setup() methods, of which the other one only allows for a single item to be ignored
+ * whereas this one will take a list of items to ignore
+ *
+ * \param desktop Reference to the desktop to which this snap manager is attached
+ * \param snapindicator If true then a snap indicator will be displayed automatically (when enabled in the preferences)
+ * \param items_to_ignore These items will not be snapped to, e.g. the items that are currently being dragged. This avoids "self-snapping"
+ * \param unselected_nodes Stationary nodes of the path that is currently being edited in the node tool and
+ * that can be snapped too. Nodes not in this list will not be snapped to, to avoid "self-snapping". Of each
+ * unselected node both the position (Geom::Point) and the type (Inkscape::SnapTargetType) will be stored
+ * \param guide_to_ignore Guide that is currently being dragged and should not be snapped to
+ */
- g_assert(dim < 2);
+void SnapManager::setup(SPDesktop const *desktop,
+ bool snapindicator,
+ std::vector<SPItem const *> &items_to_ignore,
+ std::vector<std::pair<Geom::Point, int> > *unselected_nodes,
+ SPGuide *guide_to_ignore)
+{
+ g_assert(desktop != NULL);
+ _item_to_ignore = NULL;
+ _items_to_ignore = &items_to_ignore;
+ _desktop = desktop;
+ _snapindicator = snapindicator;
+ _unselected_nodes = unselected_nodes;
+ _guide_to_ignore = guide_to_ignore;
+}
- gdouble dist = NR_HUGE;
- gdouble skew = sx;
+SPDocument *SnapManager::getDocument() const
+{
+ return _named_view->document;
+}
- for (std::vector<NR::Point>::const_iterator i = p.begin(); i != p.end(); i++) {
- NR::Point q = *i;
- NR::Point check = q;
- // apply shear
- check[dim] += sx * (q[!dim] - norm[!dim]);
- if (fabs (q[!dim] - norm[!dim]) > MIN_DIST_NORM) {
- const gdouble d = namedview_dim_snap (nv, t, check, dim, NULL);
- if (d < fabs (dist)) {
- dist = d;
- skew = (check[dim] - q[dim]) / (q[!dim] - norm[!dim]);
+/**
+ * \brief Takes an untransformed point, applies the given transformation, and returns the transformed point. Eliminates lots of duplicated code
+ *
+ * \param p The untransformed position of the point, paired with an identifier of the type of the snap source.
+ * \param transformation_type Type of transformation to apply.
+ * \param transformation Mathematical description of the transformation; details depend on the type.
+ * \param origin Origin of the transformation, if applicable.
+ * \param dim Dimension to which the transformation applies, if applicable.
+ * \param uniform true if the transformation should be uniform; only applicable for stretching and scaling.
+ * \return The position of the point after transformation
+ */
+
+Geom::Point SnapManager::_transformPoint(std::pair<Geom::Point, int> const &p,
+ Transformation const transformation_type,
+ Geom::Point const &transformation,
+ Geom::Point const &origin,
+ Geom::Dim2 const dim,
+ bool const uniform) const
+{
+ /* Work out the transformed version of this point */
+ Geom::Point transformed;
+ switch (transformation_type) {
+ case TRANSLATION:
+ transformed = p.first + transformation;
+ break;
+ case SCALE:
+ transformed = (p.first - origin) * Geom::Scale(transformation[Geom::X], transformation[Geom::Y]) + origin;
+ break;
+ case STRETCH:
+ {
+ Geom::Scale s(1, 1);
+ if (uniform)
+ s[Geom::X] = s[Geom::Y] = transformation[dim];
+ else {
+ s[dim] = transformation[dim];
+ s[1 - dim] = 1;
}
+ transformed = ((p.first - origin) * s) + origin;
+ break;
}
+ case SKEW:
+ // Apply the skew factor
+ transformed[dim] = (p.first)[dim] + transformation[0] * ((p.first)[1 - dim] - origin[1 - dim]);
+ // While skewing, mirroring and scaling (by integer multiples) in the opposite direction is also allowed.
+ // Apply that scale factor here
+ transformed[1-dim] = (p.first - origin)[1 - dim] * transformation[1] + origin[1 - dim];
+ break;
+ default:
+ g_assert_not_reached();
}
- return skew;
+ return transformed;
}
+/**
+ * \brief Mark the location of the snap source (not the snap target!) on the canvas by drawing a symbol
+ *
+ * \param point_type Category of points to which the source point belongs: node, guide or bounding box
+ * \param p The transformed position of the source point, paired with an identifier of the type of the snap source.
+ */
+
+void SnapManager::_displaySnapsource(Inkscape::SnapPreferences::PointType point_type, std::pair<Geom::Point, int> const &p) const {
+
+ Inkscape::Preferences *prefs = Inkscape::Preferences::get();
+ if (prefs->getBool("/options/snapclosestonly/value")) {
+ bool p_is_a_node = point_type & Inkscape::SnapPreferences::SNAPPOINT_NODE;
+ bool p_is_a_bbox = point_type & Inkscape::SnapPreferences::SNAPPOINT_BBOX;
+ if (snapprefs.getSnapEnabledGlobally() && ((p_is_a_node && snapprefs.getSnapModeNode()) || (p_is_a_bbox && snapprefs.getSnapModeBBox()))) {
+ _desktop->snapindicator->set_new_snapsource(p);
+ } else {
+ _desktop->snapindicator->remove_snapsource();
+ }
+ }
+}
/*
Local Variables: