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diff --git a/src/snap.cpp b/src/snap.cpp
index 537e0cd5248ce21872c061fde01d5990691e0c59..545607889c48e13f21da41c2e05150b2028be135 100644 (file)
--- a/src/snap.cpp
+++ b/src/snap.cpp
#include "desktop.h"
#include "sp-guide.h"
#include "preferences.h"
+#include "event-context.h"
using std::vector;
/**
}
/**
+ * \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
}
/**
+ * \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.
*/
SnapManager::SnapperList
{
SnapperList s;
- //FIXME: this code should actually do this: add new grid snappers that are active for this desktop. now it just adds all gridsnappers
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;
}
/**
- * \return true if one of the snappers will try to snap something.
+ * \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
}
/**
- * \return true if one of the snappers will try to snap something.
+ * \return true if one of the grids might be snapped to.
*/
bool SnapManager::gridSnapperMightSnap() const
}
/**
- * Try to snap a point to any of the specified snappers.
- *
- * \param point_type Type of point.
- * \param p Point.
- * \param first_point If true then this point is the first one from a whole bunch of points
- * \param points_to_snap The whole bunch of points, all from the same selection and having the same transformation
- * \param snappers List of snappers to try to snap to
- * \return Snapped point.
+ * \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 first_point If true then this point is the first one from a set of points, all from the same selection and having the same transformation
+ * \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,
@@ -138,34 +174,39 @@ void SnapManager::freeSnapReturnByRef(Inkscape::SnapPreferences::PointType point
bool first_point,
Geom::OptRect const &bbox_to_snap) const
{
+ //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, first_point, bbox_to_snap);
s.getPoint(p);
}
/**
- * Try to snap a point to any of the specified snappers.
- *
- * \param point_type Type of point.
- * \param p Point.
- * \param first_point If true then this point is the first one from a whole bunch of points
- * \param points_to_snap The whole bunch of points, all from the same selection and having the same transformation
- * \param snappers List of snappers to try to snap to
- * \return Snapped point.
+ * \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 first_point If true then this point is the first one from a set of points, all from the same selection and having the same transformation
+ * \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,
bool first_point,
Geom::OptRect const &bbox_to_snap) const
{
- if (_desktop->canvas->context_snap_delay_active == false) {
- g_warning("context_snap_delay_active has not been set to true by the current context. Please report this!");
- // When the context goes into dragging-mode, then Inkscape should call this: sp_canvas_set_snap_delay_active(desktop->canvas, true);
- }
-
- if (!someSnapperMightSnap()) {
+ if (!someSnapperMightSnap()) {
return Inkscape::SnappedPoint(p, source_type, Inkscape::SNAPTARGET_UNDEFINED, NR_HUGE, 0, false, false);
}
@@ -193,19 +234,30 @@ Inkscape::SnappedPoint SnapManager::freeSnap(Inkscape::SnapPreferences::PointTyp
return findBestSnap(p, source_type, sc, false);
}
-// 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 the 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!
+/**
+ * \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;
- //FIXME: this code should actually do this: add new grid snappers that are active for this desktop. now it just adds all gridsnappers
-
if (_desktop && _desktop->gridsEnabled()) {
bool success = false;
Geom::Point nearest_multiple;
}
/**
- * Try to snap a point to any interested snappers. A snap will only occur along
- * a line described by a Inkscape::Snapper::ConstraintLine.
- *
- * \param point_type Type of point.
- * \param p Point.
- * \param first_point If true then this point is the first one from a whole bunch of points
- * \param points_to_snap The whole bunch of points, all from the same selection and having the same transformation
- * \param constraint Constraint line.
- * \return Snapped point.
+ * \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 first_point If true then this point is the first one from a set of points, all from the same selection and having the same transformation
+ * \param bbox_to_snap Bounding box hulling the set of points, all from the same selection and having the same transformation
*/
void SnapManager::constrainedSnapReturnByRef(Inkscape::SnapPreferences::PointType point_type,
Geom::Point &p,
Inkscape::SnapSourceType const source_type,
Inkscape::Snapper::ConstraintLine const &constraint,
- bool const snap_projection,
bool first_point,
Geom::OptRect const &bbox_to_snap) const
{
- Inkscape::SnappedPoint const s = constrainedSnap(point_type, p, source_type, constraint, snap_projection, first_point, bbox_to_snap);
+ Inkscape::SnappedPoint const s = constrainedSnap(point_type, p, source_type, constraint, first_point, bbox_to_snap);
s.getPoint(p);
}
-
/**
- * Try to snap a point to any interested snappers. A snap will only occur along
- * a line described by a Inkscape::Snapper::ConstraintLine.
- *
- * \param point_type Type of point.
- * \param p Point.
- * \param first_point If true then this point is the first one from a whole bunch of points
- * \param points_to_snap The whole bunch of points, all from the same selection and having the same transformation
- * \param constraint Constraint line.
- * \return Snapped point.
+ * \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 first_point If true then this point is the first one from a set of points, all from the same selection and having the same transformation
+ * \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::SnapPreferences::PointType point_type,
Geom::Point const &p,
Inkscape::SnapSourceType const &source_type,
Inkscape::Snapper::ConstraintLine const &constraint,
- bool snap_projection,
bool first_point,
Geom::OptRect const &bbox_to_snap) const
{
- if (_desktop->canvas->context_snap_delay_active == false) {
- g_warning("context_snap_delay_active has not been set to true by the current context. Please report this!");
- // When the context goes into dragging-mode, then Inkscape should call this: sp_canvas_set_snap_delay_active(desktop->canvas, true);
- }
-
if (!someSnapperMightSnap()) {
return Inkscape::SnappedPoint(p, source_type, Inkscape::SNAPTARGET_UNDEFINED, NR_HUGE, 0, false, false);
}
@@ -312,7 +378,10 @@ Inkscape::SnappedPoint SnapManager::constrainedSnap(Inkscape::SnapPreferences::P
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();
@@ -324,18 +393,23 @@ Inkscape::SnappedPoint SnapManager::constrainedSnap(Inkscape::SnapPreferences::P
delete items_to_ignore;
}
- return findBestSnap(p, source_type, sc, true);
+ return findBestSnap(pp, source_type, sc, true);
}
-void SnapManager::guideSnap(Geom::Point &p, Geom::Point const &guide_normal) 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
{
- // This method is used to snap a guide to nodes or to other guides, while dragging the guide around. Will not snap to grids!
-
- if (_desktop->canvas->context_snap_delay_active == false) {
- g_warning("context_snap_delay_active has not been set to true by the current context. Please report this!");
- // When the context goes into dragging-mode, then Inkscape should call this: sp_canvas_set_snap_delay_active(desktop->canvas, true);
- }
-
if (!snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally()) {
return;
}
@@ -344,39 +418,98 @@ void SnapManager::guideSnap(Geom::Point &p, Geom::Point const &guide_normal) con
return;
}
+ 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.guideSnap(sc, p, guide_normal);
+ object.guideFreeSnap(sc, p, guide_normal);
}
- // Snap to guides
- if (snapprefs.getSnapToGuides()) {
- guide.freeSnap(sc, Inkscape::SnapPreferences::SNAPPOINT_GUIDE, p, Inkscape::SNAPSOURCE_GUIDE, true, Geom::OptRect(), NULL, 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)->freeSnap(sc, Inkscape::SnapPreferences::SNAPPOINT_GUIDE, p, source_type, true, Geom::OptRect(), NULL, NULL);
+ }
- // We won't snap to grids, what's the use?
+ // 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);
- Inkscape::SnappedPoint const s = findBestSnap(p, Inkscape::SNAPSOURCE_GUIDE, sc, false);
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, true, 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, true, Geom::OptRect(), cl, NULL);
+ }
+
+ Inkscape::SnappedPoint const s = findBestSnap(p, source_type, sc, false);
+ s.getPoint(p);
+}
/**
- * Main internal snapping method, which is called by the other, friendlier, public
- * methods. It's a bit hairy as it has lots of parameters, but it saves on a lot
- * of duplicated code.
- *
- * \param type Type of points being snapped.
- * \param points List of points to snap (i.e. untransformed).
- * \param pointer Location of the mouse pointer, at the time when dragging started (i.e. "untransformed")
- * \param constrained true if the snap is constrained.
- * \param constraint Constraint line to use, if `constrained' is true, otherwise undefined.
+ * \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 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.
*/
Inkscape::SnappedPoint SnapManager::_snapTransformed(
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, false, i == points.begin(), bbox);
+ snapped_point = constrainedSnap(type, (*j).first, static_cast<Inkscape::SnapSourceType>((*j).second), dedicated_constraint, i == points.begin(), bbox);
} else {
bool const c1 = fabs(b[Geom::X]) < 1e-6;
bool const c2 = fabs(b[Geom::Y]) < 1e-6;
// 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, false, i == points.begin(), bbox);
+ snapped_point = constrainedSnap(type, (*j).first, static_cast<Inkscape::SnapSourceType>((*j).second), dedicated_constraint, i == points.begin(), bbox);
} else {
snapped_point = freeSnap(type, (*j).first, static_cast<Inkscape::SnapSourceType>((*j).second), i == points.begin(), bbox);
}
/**
- * Try to snap a list of points to any interested snappers after they have undergone
- * a translation.
+ * \brief Apply a translation to a set of points and try to snap freely in 2 degrees-of-freedom
*
- * \param point_type Type of points.
- * \param p Points.
- * \param tr Proposed translation.
- * \return Snapped translation, if a snap occurred, and a flag indicating whether a 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.
*/
Inkscape::SnappedPoint SnapManager::freeSnapTranslation(Inkscape::SnapPreferences::PointType point_type,
@@ -631,17 +764,15 @@ Inkscape::SnappedPoint SnapManager::freeSnapTranslation(Inkscape::SnapPreference
return _snapTransformed(point_type, p, pointer, false, Geom::Point(0,0), TRANSLATION, tr, Geom::Point(0,0), Geom::X, false);
}
-
/**
- * Try to snap a list of points to any interested snappers after they have undergone a
- * translation. A snap will only occur along a line described by a
- * Inkscape::Snapper::ConstraintLine.
- *
- * \param point_type Type of points.
- * \param p Points.
- * \param constraint Constraint line.
- * \param tr Proposed translation.
- * \return Snapped translation, if a snap occurred, and a flag indicating whether a snap occurred.
+ * \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.
*/
Inkscape::SnappedPoint SnapManager::constrainedSnapTranslation(Inkscape::SnapPreferences::PointType point_type,
@@ -659,14 +790,14 @@ Inkscape::SnappedPoint SnapManager::constrainedSnapTranslation(Inkscape::SnapPre
/**
- * Try to snap a list of points to any interested snappers after they have undergone
- * a scale.
- *
- * \param point_type Type of points.
- * \param p Points.
- * \param s Proposed scale.
- * \param o Origin of proposed scale.
- * \return Snapped scale, if a snap occurred, and a flag indicating whether a snap occurred.
+ * \brief Apply a scaling to a set of points and try to snap freely in 2 degrees-of-freedom
+ *
+ * \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::freeSnapScale(Inkscape::SnapPreferences::PointType point_type,
@@ -684,15 +815,14 @@ Inkscape::SnappedPoint SnapManager::freeSnapScale(Inkscape::SnapPreferences::Poi
/**
- * Try to snap a list of points to any interested snappers after they have undergone
- * a scale. A snap will only occur along a line described by a
- * Inkscape::Snapper::ConstraintLine.
- *
- * \param point_type Type of points.
- * \param p Points.
- * \param s Proposed scale.
- * \param o Origin of proposed scale.
- * \return Snapped scale, if a snap occurred, and a flag indicating whether a snap occurred.
+ * \brief Apply a scaling to a set of points and snap such that the aspect ratio of the selection 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 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,
@@ -709,18 +839,17 @@ Inkscape::SnappedPoint SnapManager::constrainedSnapScale(Inkscape::SnapPreferenc
return _snapTransformed(point_type, p, pointer, true, Geom::Point(0,0), SCALE, Geom::Point(s[Geom::X], s[Geom::Y]), o, Geom::X, true);
}
-
/**
- * Try to snap a list of points to any interested snappers after they have undergone
- * a stretch.
+ * \brief Apply a stretch to a set of points and snap such that the direction of the stretch is preserved
*
- * \param point_type Type of points.
- * \param p Points.
- * \param s Proposed stretch.
- * \param o Origin of proposed stretch.
+ * \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 (ie to be applied equally in both dimensions)
- * \return Snapped stretch, if a snap occurred, and a flag indicating whether a snap occurred.
+ * \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.
*/
Inkscape::SnappedPoint SnapManager::constrainedSnapStretch(Inkscape::SnapPreferences::PointType point_type,
@@ -738,17 +867,17 @@ Inkscape::SnappedPoint SnapManager::constrainedSnapStretch(Inkscape::SnapPrefere
return _snapTransformed(point_type, p, pointer, true, Geom::Point(0,0), STRETCH, Geom::Point(s, s), o, d, u);
}
-
/**
- * Try to snap a list of points to any interested snappers after they have undergone
- * a skew.
+ * \brief Apply a skew to a set of points and snap such that the direction of the skew is preserved
*
- * \param point_type Type of points.
- * \param p Points.
- * \param s Proposed skew.
- * \param o Origin of proposed skew.
+ * \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 Snapped skew, if a snap occurred, and a flag indicating whether a snap occurred.
+ * \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,
@@ -761,7 +890,7 @@ Inkscape::SnappedPoint SnapManager::constrainedSnapSkew(Inkscape::SnapPreference
{
// "s" contains skew factor in s[0], and scale factor in s[1]
- // Snapping the nodes of the boundingbox of a selection that is being transformed, will only work if
+ // 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
@@ -775,7 +904,23 @@ Inkscape::SnappedPoint SnapManager::constrainedSnapSkew(Inkscape::SnapPreference
return _snapTransformed(point_type, p, pointer, true, constraint, SKEW, s, o, d, false);
}
-Inkscape::SnappedPoint SnapManager::findBestSnap(Geom::Point const &p, Inkscape::SnapSourceType const source_type, SnappedConstraints &sc, bool constrained) const
+/**
+ * \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
+ *
+ * \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
+ */
+
+Inkscape::SnappedPoint SnapManager::findBestSnap(Geom::Point const &p,
+ Inkscape::SnapSourceType const source_type,
+ SnappedConstraints &sc,
+ bool constrained,
+ bool noCurves) const
{
/*
@@ -797,9 +942,11 @@ Inkscape::SnappedPoint SnapManager::findBestSnap(Geom::Point const &p, Inkscape:
}
// search for the closest snapped curve
- Inkscape::SnappedCurve closestCurve;
- if (getClosestCurve(sc.curves, closestCurve)) {
- sp_list.push_back(Inkscape::SnappedPoint(closestCurve));
+ if (!noCurves) {
+ Inkscape::SnappedCurve closestCurve;
+ if (getClosestCurve(sc.curves, closestCurve)) {
+ sp_list.push_back(Inkscape::SnappedPoint(closestCurve));
+ }
}
if (snapprefs.getSnapIntersectionCS()) {
@@ -886,6 +1033,22 @@ Inkscape::SnappedPoint SnapManager::findBestSnap(Geom::Point const &p, Inkscape:
return bestSnappedPoint;
}
+/**
+ * \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
+ */
+
void SnapManager::setup(SPDesktop const *desktop,
bool snapindicator,
SPItem const *item_to_ignore,
_guide_to_ignore = guide_to_ignore;
}
+/**
+ * \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
+ */
+
void SnapManager::setup(SPDesktop const *desktop,
bool snapindicator,
std::vector<SPItem const *> &items_to_ignore,
return _named_view->document;
}
+/**
+ * \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,
@@ -963,6 +1154,13 @@ Geom::Point SnapManager::_transformPoint(std::pair<Geom::Point, int> const &p,
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();