/* * SnapManager class. * * Authors: * Lauris Kaplinski * Frank Felfe * Nathan Hurst * Carl Hetherington * Diederik van Lierop * * Copyright (C) 2006-2007 Johan Engelen * Copyrigth (C) 2004 Nathan Hurst * Copyright (C) 1999-2012 Authors * * Released under GNU GPL, read the file 'COPYING' for more information */ #include #include <2geom/transforms.h> #include "sp-namedview.h" #include "snap.h" #include "snap-enums.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 "selection.h" #include "sp-guide.h" #include "preferences.h" #include "ui/tools/tool-base.h" #include "helper/mathfns.h" using std::vector; using Inkscape::Util::round_to_upper_multiple_plus; using Inkscape::Util::round_to_lower_multiple_plus; SnapManager::SnapManager(SPNamedView const *v) : guide(this, 0), object(this, 0), snapprefs(), _named_view(v), _rotation_center_source_items(NULL), _guide_to_ignore(NULL), _desktop(NULL), _snapindicator(true), _unselected_nodes(NULL) { } SnapManager::SnapperList SnapManager::getSnappers() const { SnapManager::SnapperList s; s.push_back(&guide); s.push_back(&object); SnapManager::SnapperList gs = getGridSnappers(); s.splice(s.begin(), gs); return s; } SnapManager::SnapperList SnapManager::getGridSnappers() const { SnapperList s; if (_desktop && _desktop->gridsEnabled() && snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_GRID)) { 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; } bool SnapManager::someSnapperMightSnap(bool immediately) const { if ( !snapprefs.getSnapEnabledGlobally() ) { return false; } // If we're asking if some snapper might snap RIGHT NOW (without the snap being postponed)... if ( immediately && snapprefs.getSnapPostponedGlobally() ) { return false; } SnapperList const s = getSnappers(); SnapperList::const_iterator i = s.begin(); while (i != s.end() && (*i)->ThisSnapperMightSnap() == false) { ++i; } return (i != s.end()); } bool SnapManager::gridSnapperMightSnap() const { if ( !snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally() ) { return false; } SnapperList const s = getGridSnappers(); SnapperList::const_iterator i = s.begin(); while (i != s.end() && (*i)->ThisSnapperMightSnap() == false) { ++i; } return (i != s.end()); } void SnapManager::freeSnapReturnByRef(Geom::Point &p, Inkscape::SnapSourceType const source_type, Geom::OptRect const &bbox_to_snap) const { Inkscape::SnappedPoint const s = freeSnap(Inkscape::SnapCandidatePoint(p, source_type, Inkscape::SNAPTARGET_PATH), bbox_to_snap); s.getPointIfSnapped(p); } Inkscape::SnappedPoint SnapManager::freeSnap(Inkscape::SnapCandidatePoint const &p, Geom::OptRect const &bbox_to_snap) const { if (!someSnapperMightSnap()) { return Inkscape::SnappedPoint(p, Inkscape::SNAPTARGET_UNDEFINED, Geom::infinity(), 0, false, false, false); } IntermSnapResults isr; SnapperList const snappers = getSnappers(); for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); ++i) { (*i)->freeSnap(isr, p, bbox_to_snap, &_items_to_ignore, _unselected_nodes); } return findBestSnap(p, isr, false); } void SnapManager::preSnap(Inkscape::SnapCandidatePoint const &p) { // setup() must have been called before calling this method! if (_snapindicator) { _snapindicator = false; // prevent other methods from drawing a snap indicator; we want to control this here Inkscape::SnappedPoint s = freeSnap(p); g_assert(_desktop != NULL); if (s.getSnapped()) { _desktop->snapindicator->set_new_snaptarget(s, true); } else { _desktop->snapindicator->remove_snaptarget(true); } _snapindicator = true; // restore the original value } } Geom::Point SnapManager::multipleOfGridPitch(Geom::Point const &t, Geom::Point const &origin) { if (!snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally()) return t; if (_desktop && _desktop->gridsEnabled()) { bool success = false; Geom::Point nearest_multiple; Geom::Coord nearest_distance = Geom::infinity(); Inkscape::SnappedPoint bestSnappedPoint(t); // 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; IntermSnapResults isr; // Only the first three parameters are being used for grid snappers snapper->freeSnap(isr, Inkscape::SnapCandidatePoint(t_offset, Inkscape::SNAPSOURCE_GRID_PITCH),Geom::OptRect(), NULL, NULL); // Find the best snap for this grid, including intersections of the grid-lines bool old_val = _snapindicator; _snapindicator = false; Inkscape::SnappedPoint s = findBestSnap(Inkscape::SnapCandidatePoint(t_offset, Inkscape::SNAPSOURCE_GRID_PITCH), isr, false, true); _snapindicator = old_val; 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() - grid->origin; nearest_distance = s.getSnapDistance(); bestSnappedPoint = s; } } } if (success) { bestSnappedPoint.setPoint(origin + nearest_multiple); _desktop->snapindicator->set_new_snaptarget(bestSnappedPoint); return nearest_multiple; } } return t; } void SnapManager::constrainedSnapReturnByRef(Geom::Point &p, Inkscape::SnapSourceType const source_type, Inkscape::Snapper::SnapConstraint const &constraint, Geom::OptRect const &bbox_to_snap) const { Inkscape::SnappedPoint const s = constrainedSnap(Inkscape::SnapCandidatePoint(p, source_type), constraint, bbox_to_snap); p = s.getPoint(); // If we didn't snap, then we will return the point projected onto the constraint } Inkscape::SnappedPoint SnapManager::constrainedSnap(Inkscape::SnapCandidatePoint const &p, Inkscape::Snapper::SnapConstraint const &constraint, Geom::OptRect const &bbox_to_snap) const { // First project the mouse pointer onto the constraint Geom::Point pp = constraint.projection(p.getPoint()); Inkscape::SnappedPoint no_snap = Inkscape::SnappedPoint(pp, p.getSourceType(), p.getSourceNum(), Inkscape::SNAPTARGET_CONSTRAINT, Geom::infinity(), 0, false, true, false); if (!someSnapperMightSnap()) { // Always return point on constraint return no_snap; } Inkscape::SnappedPoint result = no_snap; Inkscape::Preferences *prefs = Inkscape::Preferences::get(); if ((prefs->getBool("/options/snapmousepointer/value", false)) && p.isSingleHandle()) { // Snapping the mouse pointer instead of the constrained position of the knot allows // to snap to things which don't intersect with the constraint line; this is basically // then just a freesnap with the constraint applied afterwards // We'll only do this if we're dragging a single handle, and for example not when transforming an object in the selector tool result = freeSnap(p, bbox_to_snap); if (result.getSnapped()) { // only change the snap indicator if we really snapped to something if (_snapindicator && _desktop) { _desktop->snapindicator->set_new_snaptarget(result); } // Apply the constraint result.setPoint(constraint.projection(result.getPoint())); return result; } return no_snap; } IntermSnapResults isr; SnapperList const snappers = getSnappers(); for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); ++i) { (*i)->constrainedSnap(isr, p, bbox_to_snap, constraint, &_items_to_ignore, _unselected_nodes); } result = findBestSnap(p, isr, true); if (result.getSnapped()) { // only change the snap indicator if we really snapped to something if (_snapindicator && _desktop) { _desktop->snapindicator->set_new_snaptarget(result); } return result; } return no_snap; } /* See the documentation for constrainedSnap() directly above for more details. * The difference is that multipleConstrainedSnaps() will take a list of constraints instead of a single one, * and will try to snap the SnapCandidatePoint to only the closest constraint * \param p Source point to be snapped * \param constraints List of directions or lines along which snapping must occur * \param dont_snap If true then we will only apply the constraint, without snapping * \param bbox_to_snap Bounding box hulling the set of points, all from the same selection and having the same transformation */ Inkscape::SnappedPoint SnapManager::multipleConstrainedSnaps(Inkscape::SnapCandidatePoint const &p, std::vector const &constraints, bool dont_snap, Geom::OptRect const &bbox_to_snap) const { Inkscape::SnappedPoint no_snap = Inkscape::SnappedPoint(p.getPoint(), p.getSourceType(), p.getSourceNum(), Inkscape::SNAPTARGET_CONSTRAINT, Geom::infinity(), 0, false, true, false); if (constraints.size() == 0) { return no_snap; } // We haven't tried to snap yet; we will first determine which constraint is closest to where we are now, // i.e. lets find out which of the constraints yields the closest projection of point p // Project the mouse pointer on each of the constraints std::vector projections; for (std::vector::const_iterator c = constraints.begin(); c != constraints.end(); ++c) { // Project the mouse pointer onto the constraint; In case we don't snap then we will // return the projection onto the constraint, such that the constraint is always enforced Geom::Point pp = (*c).projection(p.getPoint()); projections.push_back(pp); } // Select the closest constraint no_snap.setPoint(projections.front()); Inkscape::Snapper::SnapConstraint cc = constraints.front(); //closest constraint std::vector::const_iterator c = constraints.begin(); std::vector::iterator pp = projections.begin(); for (; pp != projections.end(); ++pp) { if (Geom::L2(*pp - p.getPoint()) < Geom::L2(no_snap.getPoint() - p.getPoint())) { no_snap.setPoint(*pp); // Remember the projection onto the closest constraint cc = *c; // Remember the closest constraint itself } ++c; } if (!someSnapperMightSnap() || dont_snap) { return no_snap; } IntermSnapResults isr; SnapperList const snappers = getSnappers(); Inkscape::Preferences *prefs = Inkscape::Preferences::get(); bool snap_mouse = prefs->getBool("/options/snapmousepointer/value", false); Inkscape::SnappedPoint result = no_snap; if (snap_mouse && p.isSingleHandle()) { // Snapping the mouse pointer instead of the constrained position of the knot allows // to snap to things which don't intersect with the constraint line; this is basically // then just a freesnap with the constraint applied afterwards // We'll only to this if we're dragging a single handle, and for example not when transforming an object in the selector tool result = freeSnap(p, bbox_to_snap); // Now apply the constraint afterwards result.setPoint(cc.projection(result.getPoint())); } else { // Try to snap along the closest constraint for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); ++i) { (*i)->constrainedSnap(isr, p, bbox_to_snap, cc, &_items_to_ignore,_unselected_nodes); } result = findBestSnap(p, isr, true); } return result.getSnapped() ? result : no_snap; } Inkscape::SnappedPoint SnapManager::constrainedAngularSnap(Inkscape::SnapCandidatePoint const &p, boost::optional const &p_ref, Geom::Point const &o, unsigned const snaps) const { Inkscape::SnappedPoint sp; if (snaps > 0) { // 0 means no angular snapping // p is at an arbitrary angle. Now we should snap this angle to specific increments. // For this we'll calculate the closest two angles, one at each side of the current angle Geom::Line y_axis(Geom::Point(0, 0), Geom::Point(0, 1)); Geom::Line p_line(o, p.getPoint()); double angle = Geom::angle_between(y_axis, p_line); double angle_incr = M_PI / snaps; double angle_offset = 0; if (p_ref) { Geom::Line p_line_ref(o, *p_ref); angle_offset = Geom::angle_between(y_axis, p_line_ref); } double angle_ceil = round_to_upper_multiple_plus(angle, angle_incr, angle_offset); double angle_floor = round_to_lower_multiple_plus(angle, angle_incr, angle_offset); // We have two angles now. The constrained snapper will try each of them and return the closest // Now do the snapping... std::vector constraints; constraints.push_back(Inkscape::Snapper::SnapConstraint(Geom::Line(o, angle_ceil - M_PI/2))); constraints.push_back(Inkscape::Snapper::SnapConstraint(Geom::Line(o, angle_floor - M_PI/2))); sp = multipleConstrainedSnaps(p, constraints); // Constraints will always be applied, even if we didn't snap if (!sp.getSnapped()) { // If we haven't snapped then we only had the constraint applied; sp.setTarget(Inkscape::SNAPTARGET_CONSTRAINED_ANGLE); } } else { sp = freeSnap(p); } return sp; } void SnapManager::guideFreeSnap(Geom::Point &p, Geom::Point &origin_or_vector, bool origin, bool freeze_angle) const { if (freeze_angle && origin) { g_warning("Dear developer, when snapping guides you shouldn't ask me to freeze the guide's vector when you haven't specified one"); // You've supplied me with an origin instead of a vector } if (!snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally() || !snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_GUIDE)) { return; } Inkscape::SnapCandidatePoint candidate(p, Inkscape::SNAPSOURCE_GUIDE); if (origin) { candidate.addOrigin(origin_or_vector); } else { candidate = Inkscape::SnapCandidatePoint(p, Inkscape::SNAPSOURCE_GUIDE_ORIGIN); candidate.addVector(Geom::rot90(origin_or_vector)); } IntermSnapResults isr; SnapperList snappers = getSnappers(); for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); ++i) { (*i)->freeSnap(isr, candidate, Geom::OptRect(), NULL, NULL); } Inkscape::SnappedPoint const s = findBestSnap(candidate, isr, false); s.getPointIfSnapped(p); if (!freeze_angle && s.getSnapped()) { if (!Geom::are_near(s.getTangent(), Geom::Point(0,0))) { // If the tangent has been set ... origin_or_vector = Geom::rot90(s.getTangent()); // then use it to update the normal of the guide // PS: The tangent might not have been set if we snapped for example to a node } } } void SnapManager::guideConstrainedSnap(Geom::Point &p, SPGuide const &guideline) const { if (!snapprefs.getSnapEnabledGlobally() || snapprefs.getSnapPostponedGlobally() || !snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_GUIDE)) { return; } Inkscape::SnapCandidatePoint candidate(p, Inkscape::SNAPSOURCE_GUIDE_ORIGIN, Inkscape::SNAPTARGET_UNDEFINED); IntermSnapResults isr; Inkscape::Snapper::SnapConstraint cl(guideline.getPoint(), Geom::rot90(guideline.getNormal())); SnapperList snappers = getSnappers(); for (SnapperList::const_iterator i = snappers.begin(); i != snappers.end(); ++i) { (*i)->constrainedSnap(isr, candidate, Geom::OptRect(), cl, NULL, NULL); } Inkscape::SnappedPoint const s = findBestSnap(candidate, isr, false); s.getPointIfSnapped(p); } Inkscape::SnappedPoint SnapManager::_snapTransformed( std::vector const &points, Geom::Point const &pointer, bool constrained, Inkscape::Snapper::SnapConstraint const &constraint, Transformation transformation_type, Geom::Point const &transformation, Geom::Point const &origin, Geom::Dim2 dim, bool uniform) { /* 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'. */ if (points.size() == 0) { return Inkscape::SnappedPoint(pointer); } std::vector transformed_points; Geom::Rect bbox; long source_num = 0; for (std::vector::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(Inkscape::SnapCandidatePoint(transformed, (*i).getSourceType(), source_num, Inkscape::SNAPTARGET_UNDEFINED, Geom::OptRect())); source_num++; } /* The current best transformation */ Geom::Point best_transformation = transformation; /* The current best metric for the best transformation; lower is better, Geom::infinity() ** means that we haven't snapped anything. */ Inkscape::SnappedPoint best_snapped_point; g_assert(best_snapped_point.getAlwaysSnap() == false); // Check initialization of snapped point g_assert(best_snapped_point.getAtIntersection() == false); // Warnings for the devs if (constrained && transformation_type == SCALE && !uniform) { g_warning("Non-uniform constrained scaling is not supported!"); } if (!constrained && transformation_type == ROTATE) { // We do not yet allow for simultaneous rotation and scaling g_warning("Unconstrained rotation is not supported!"); } // We will try to snap a set of points, but we don't want to have a snap indicator displayed // for each of them. That's why it's temporarily disabled here, and re-enabled again after we // have finished calling the freeSnap() and constrainedSnap() methods bool _orig_snapindicator_status = _snapindicator; _snapindicator = false; std::vector::iterator j = transformed_points.begin(); // std::cout << std::endl; bool first_free_snap = true; for (std::vector::const_iterator i = points.begin(); i != points.end(); ++i) { /* Snap it */ Inkscape::SnappedPoint snapped_point; Inkscape::Snapper::SnapConstraint dedicated_constraint = constraint; Geom::Point const b = ((*i).getPoint() - origin); // vector to original point (not the transformed point! required for rotations!) 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::SnapConstraint(origin, b); } else if (transformation_type == ROTATE) { Geom::Coord r = Geom::L2(b); // the radius of the circular constraint dedicated_constraint = Inkscape::Snapper::SnapConstraint(origin, b, r); } else if (transformation_type == STRETCH) { // when non-uniform stretching { Geom::Point cvec; cvec[dim] = 1.; dedicated_constraint = Inkscape::Snapper::SnapConstraint((*i).getPoint(), cvec); } else if (transformation_type == TRANSLATE) { // 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 specify the point through // which the constraint-line runs here, for each point individually. (we could also have done this // earlier on, e.g. in seltrans.cpp but we're being lazy there and don't want to add an iteration loop) dedicated_constraint = Inkscape::Snapper::SnapConstraint((*i).getPoint(), constraint.getDirection()); } // else: leave the original constraint, e.g. for skewing snapped_point = constrainedSnap(*j, dedicated_constraint, 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 Geom::Point cvec; cvec[c1] = 1.; dedicated_constraint = Inkscape::Snapper::SnapConstraint(origin, cvec); snapped_point = constrainedSnap(*j, dedicated_constraint, bbox); } else { // If we have a collection of SnapCandidatePoints, with mixed constrained snapping and free snapping // requirements, then freeSnap might never see the SnapCandidatePoint with source_num == 0. The freeSnap() // method in the object snapper depends on this, because only for source-num == 0 the target nodes will // be collected. Therefore we enforce that the first SnapCandidatePoint that is to be freeSnapped always // has source_num == 0; // TODO: This is a bit ugly so fix this; do we need sourcenum for anything else? if we don't then get rid // of it and explicitly communicate to the object snapper that this is a first point if (first_free_snap) { (*j).setSourceNum(0); first_free_snap = false; } snapped_point = freeSnap(*j, bbox); } } // std::cout << "dist = " << snapped_point.getSnapDistance() << std::endl; snapped_point.setPointerDistance(Geom::L2(pointer - (*i).getPoint())); // Allow the snapindicator to be displayed again _snapindicator = _orig_snapindicator_status; Geom::Point result; /*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 TRANSLATE: result = snapped_point.getPoint() - (*i).getPoint(); /* 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 over 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 to an intersection 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(Geom::infinity(), Geom::infinity()); // 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 of course) for (int index = 0; index < 2; index++) { if (fabs(b[index]) > 1e-4) { // if SCALING CAN occur in this direction if (fabs(fabs(a[index]/b[index]) - fabs(transformation[index])) > 1e-7) { // if SNAPPING DID occur in this direction result[index] = a[index] / b[index]; // then calculate it! } // we might have left result[1-index] = Geom::infinity() // if scaling didn't occur in the other direction } } if (uniform) { if (fabs(result[0]) < fabs(result[1])) { result[1] = result[0]; } else { result[0] = result[1]; } } // Compare the resulting scaling with the desired scaling Geom::Point scale_metric = result - transformation; // One or both of its components might be Geom::infinity() scale_metric[0] = fabs(scale_metric[0]); scale_metric[1] = fabs(scale_metric[1]); if (scale_metric[0] == Geom::infinity() || scale_metric[1] == Geom::infinity()) { snapped_point.setSnapDistance(std::min(scale_metric[0], scale_metric[1])); } else { snapped_point.setSnapDistance(Geom::L2(scale_metric)); } snapped_point.setSecondSnapDistance(Geom::infinity()); break; } case STRETCH: result = Geom::Point(Geom::infinity(), Geom::infinity()); 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(Geom::infinity()); break; case SKEW: result[0] = (snapped_point.getPoint()[dim] - ((*i).getPoint())[dim]) / b[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(Geom::infinity()); break; case ROTATE: // a is vector to snapped point; b is vector to original point; now lets calculate angle between a and b result[0] = atan2(Geom::dot(Geom::rot90(b), a), Geom::dot(b, a)); result[1] = result[0]; // dummy value; how else should we store an angle in a point ;-) if (Geom::L2(b) < 1e-9) { // points too close to the rotation center will not move. Don't try to snap these // as they will always yield a perfect snap result if they're already snapped beforehand (e.g. // when the transformation center has been snapped to a grid intersection in the selector tool) snapped_point.setSnapDistance(Geom::infinity()); // PS1: Apparently we don't have to do this for skewing, but why? // PS2: We cannot easily filter these points upstream, e.g. in the grab() method (seltrans.cpp) // because the rotation center will change when pressing shift, and grab() won't be recalled. // Filtering could be done in handleRequest() (again in seltrans.cpp), by iterating through // the snap candidates. But hey, we're iterating here anyway. } else { snapped_point.setSnapDistance(std::abs(result[0] - transformation[0])); } snapped_point.setSecondSnapDistance(Geom::infinity()); break; default: g_assert_not_reached(); } if (snapped_point.getSnapped()) { // We snapped; keep track of the best snap if (best_snapped_point.isOtherSnapBetter(snapped_point, true)) { best_transformation = result; best_snapped_point = snapped_point; } } else { // So we didn't snap for this point if (!best_snapped_point.getSnapped()) { // ... and none of the points before snapped either // We might still need to apply a constraint though, if we tried a constrained snap. And // in case of a free snap we might have use for the transformed point, so let's return that // point, whether it's constrained or not if (best_snapped_point.isOtherSnapBetter(snapped_point, true) || points.size() == 1) { // .. so we must keep track of the best non-snapped constrained point best_transformation = result; best_snapped_point = snapped_point; } } } ++j; } Geom::Coord best_metric; if (transformation_type == SCALE) { // When scaling, don't ever exit with one of scaling components uninitialized for (int index = 0; index < 2; index++) { if (fabs(best_transformation[index]) == Geom::infinity()) { if (uniform && fabs(best_transformation[1-index]) < Geom::infinity()) { best_transformation[index] = best_transformation[1-index]; } else { best_transformation[index] = transformation[index]; } } } } best_metric = best_snapped_point.getSnapDistance(); best_snapped_point.setTransformation(best_transformation); // Using " < 1e6" instead of " < Geom::infinity()" 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 : Geom::infinity()); if (_snapindicator) { if (best_snapped_point.getSnapped()) { _desktop->snapindicator->set_new_snaptarget(best_snapped_point); } else { _desktop->snapindicator->remove_snaptarget(); } } return best_snapped_point; } Inkscape::SnappedPoint SnapManager::freeSnapTranslate(std::vector const &p, Geom::Point const &pointer, Geom::Point const &tr) { Inkscape::SnappedPoint result = _snapTransformed(p, pointer, false, Geom::Point(0,0), TRANSLATE, tr, Geom::Point(0,0), Geom::X, false); if (p.size() == 1) { displaySnapsource(Inkscape::SnapCandidatePoint(result.getPoint(), p.at(0).getSourceType())); } return result; } Inkscape::SnappedPoint SnapManager::constrainedSnapTranslate(std::vector const &p, Geom::Point const &pointer, Inkscape::Snapper::SnapConstraint const &constraint, Geom::Point const &tr) { Inkscape::SnappedPoint result = _snapTransformed(p, pointer, true, constraint, TRANSLATE, tr, Geom::Point(0,0), Geom::X, false); if (p.size() == 1) { displaySnapsource(Inkscape::SnapCandidatePoint(result.getPoint(), p.at(0).getSourceType())); } return result; } Inkscape::SnappedPoint SnapManager::freeSnapScale(std::vector const &p, Geom::Point const &pointer, Geom::Scale const &s, Geom::Point const &o) { Inkscape::SnappedPoint result = _snapTransformed(p, pointer, false, Geom::Point(0,0), SCALE, Geom::Point(s[Geom::X], s[Geom::Y]), o, Geom::X, false); if (p.size() == 1) { displaySnapsource(Inkscape::SnapCandidatePoint(result.getPoint(), p.at(0).getSourceType())); } return result; } Inkscape::SnappedPoint SnapManager::constrainedSnapScale(std::vector const &p, Geom::Point const &pointer, Geom::Scale const &s, Geom::Point const &o) { // When constrained scaling, only uniform scaling is supported. Inkscape::SnappedPoint result = _snapTransformed(p, pointer, true, Geom::Point(0,0), SCALE, Geom::Point(s[Geom::X], s[Geom::Y]), o, Geom::X, true); if (p.size() == 1) { displaySnapsource(Inkscape::SnapCandidatePoint(result.getPoint(), p.at(0).getSourceType())); } return result; } Inkscape::SnappedPoint SnapManager::constrainedSnapStretch(std::vector const &p, Geom::Point const &pointer, Geom::Coord const &s, Geom::Point const &o, Geom::Dim2 d, bool u) { Inkscape::SnappedPoint result = _snapTransformed(p, pointer, true, Geom::Point(0,0), STRETCH, Geom::Point(s, s), o, d, u); if (p.size() == 1) { displaySnapsource(Inkscape::SnapCandidatePoint(result.getPoint(), p.at(0).getSourceType())); } return result; } Inkscape::SnappedPoint SnapManager::constrainedSnapSkew(std::vector const &p, Geom::Point const &pointer, Inkscape::Snapper::SnapConstraint const &constraint, Geom::Point const &s, Geom::Point const &o, Geom::Dim2 d) { // "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. if (!p.empty()) { g_assert(!(p.at(0).getSourceType() & Inkscape::SNAPSOURCE_BBOX_CATEGORY)); } Inkscape::SnappedPoint result = _snapTransformed(p, pointer, true, constraint, SKEW, s, o, d, false); if (p.size() == 1) { displaySnapsource(Inkscape::SnapCandidatePoint(result.getPoint(), p.at(0).getSourceType())); } return result; } Inkscape::SnappedPoint SnapManager::constrainedSnapRotate(std::vector const &p, Geom::Point const &pointer, Geom::Coord const &angle, Geom::Point const &o) { // 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. Inkscape::SnappedPoint result = _snapTransformed(p, pointer, true, Geom::Point(0,0), ROTATE, Geom::Point(angle, angle), o, Geom::X, false); if (p.size() == 1) { displaySnapsource(Inkscape::SnapCandidatePoint(result.getPoint(), p.at(0).getSourceType())); } return result; } Inkscape::SnappedPoint SnapManager::findBestSnap(Inkscape::SnapCandidatePoint const &p, IntermSnapResults const &isr, bool constrained, bool allowOffScreen) const { g_assert(_desktop != NULL); /* std::cout << "Type and number of snapped constraints: " << std::endl; std::cout << " Points : " << isr.points.size() << std::endl; std::cout << " Grid lines : " << isr.grid_lines.size()<< std::endl; std::cout << " Guide lines : " << isr.guide_lines.size()<< std::endl; std::cout << " Curves : " << isr.curves.size()<< std::endl; */ /* // Display all snap candidates on the canvas _desktop->snapindicator->remove_debugging_points(); for (std::list::const_iterator i = isr.points.begin(); i != isr.points.end(); i++) { _desktop->snapindicator->set_new_debugging_point((*i).getPoint()); } for (std::list::const_iterator i = isr.curves.begin(); i != isr.curves.end(); i++) { _desktop->snapindicator->set_new_debugging_point((*i).getPoint()); } for (std::list::const_iterator i = isr.grid_lines.begin(); i != isr.grid_lines.end(); i++) { _desktop->snapindicator->set_new_debugging_point((*i).getPoint()); } for (std::list::const_iterator i = isr.guide_lines.begin(); i != isr.guide_lines.end(); i++) { _desktop->snapindicator->set_new_debugging_point((*i).getPoint()); } */ // Store all snappoints std::list sp_list; // search for the closest snapped point Inkscape::SnappedPoint closestPoint; if (getClosestSP(isr.points, closestPoint)) { sp_list.push_back(closestPoint); } // search for the closest snapped curve Inkscape::SnappedCurve closestCurve; // We might have collected the paths only to snap to their intersection, without the intention to snap to the paths themselves // Therefore we explicitly check whether the paths should be considered as snap targets themselves bool exclude_paths = !snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_PATH); if (getClosestCurve(isr.curves, closestCurve, exclude_paths)) { sp_list.push_back(Inkscape::SnappedPoint(closestCurve)); } // search for the closest snapped grid line Inkscape::SnappedLine closestGridLine; if (getClosestSL(isr.grid_lines, closestGridLine)) { sp_list.push_back(Inkscape::SnappedPoint(closestGridLine)); } // search for the closest snapped guide line Inkscape::SnappedLine closestGuideLine; if (getClosestSL(isr.guide_lines, closestGuideLine)) { sp_list.push_back(Inkscape::SnappedPoint(closestGuideLine)); } // 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) { if (snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_PATH_INTERSECTION)) { // search for the closest snapped intersection of curves Inkscape::SnappedPoint closestCurvesIntersection; if (getClosestIntersectionCS(isr.curves, p.getPoint(), closestCurvesIntersection, _desktop->dt2doc())) { closestCurvesIntersection.setSource(p.getSourceType()); sp_list.push_back(closestCurvesIntersection); } } if (snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_PATH_GUIDE_INTERSECTION)) { // search for the closest snapped intersection of a guide with a curve Inkscape::SnappedPoint closestCurveGuideIntersection; if (getClosestIntersectionCL(isr.curves, isr.guide_lines, p.getPoint(), closestCurveGuideIntersection, _desktop->dt2doc())) { closestCurveGuideIntersection.setSource(p.getSourceType()); sp_list.push_back(closestCurveGuideIntersection); } } // search for the closest snapped intersection of grid lines Inkscape::SnappedPoint closestGridPoint; if (getClosestIntersectionSL(isr.grid_lines, closestGridPoint)) { closestGridPoint.setSource(p.getSourceType()); closestGridPoint.setTarget(Inkscape::SNAPTARGET_GRID_INTERSECTION); sp_list.push_back(closestGridPoint); } // search for the closest snapped intersection of guide lines Inkscape::SnappedPoint closestGuidePoint; if (getClosestIntersectionSL(isr.guide_lines, closestGuidePoint)) { closestGuidePoint.setSource(p.getSourceType()); closestGuidePoint.setTarget(Inkscape::SNAPTARGET_GUIDE_INTERSECTION); sp_list.push_back(closestGuidePoint); } // search for the closest snapped intersection of grid with guide lines if (snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_GRID_GUIDE_INTERSECTION)) { Inkscape::SnappedPoint closestGridGuidePoint; if (getClosestIntersectionSL(isr.grid_lines, isr.guide_lines, closestGridGuidePoint)) { closestGridGuidePoint.setSource(p.getSourceType()); closestGridGuidePoint.setTarget(Inkscape::SNAPTARGET_GRID_GUIDE_INTERSECTION); sp_list.push_back(closestGridGuidePoint); } } } // now let's see which snapped point gets a thumbs up Inkscape::SnappedPoint bestSnappedPoint(p.getPoint()); // std::cout << "Finding the best snap..." << std::endl; for (std::list::const_iterator i = sp_list.begin(); i != sp_list.end(); ++i) { // std::cout << "sp = " << (*i).getPoint() << " | source = " << (*i).getSource() << " | target = " << (*i).getTarget(); bool onScreen = _desktop->get_display_area().contains((*i).getPoint()); if (onScreen || allowOffScreen) { // Only snap to points which are not off the screen if ((*i).getSnapDistance() <= (*i).getTolerance()) { // Only snap to points within snapping range // 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; } // 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; } void SnapManager::setup(SPDesktop const *desktop, bool snapindicator, SPItem const *item_to_ignore, std::vector *unselected_nodes, SPGuide *guide_to_ignore) { g_assert(desktop != NULL); if (_desktop != NULL) { g_warning("The snapmanager has been set up before, but unSetup() hasn't been called afterwards. It possibly held invalid pointers"); } _items_to_ignore.clear(); _items_to_ignore.push_back(item_to_ignore); _desktop = desktop; _snapindicator = snapindicator; _unselected_nodes = unselected_nodes; _guide_to_ignore = guide_to_ignore; _rotation_center_source_items = NULL; } void SnapManager::setup(SPDesktop const *desktop, bool snapindicator, std::vector &items_to_ignore, std::vector *unselected_nodes, SPGuide *guide_to_ignore) { g_assert(desktop != NULL); if (_desktop != NULL) { g_warning("The snapmanager has been set up before, but unSetup() hasn't been called afterwards. It possibly held invalid pointers"); } _items_to_ignore = items_to_ignore; _desktop = desktop; _snapindicator = snapindicator; _unselected_nodes = unselected_nodes; _guide_to_ignore = guide_to_ignore; _rotation_center_source_items = NULL; } /// Setup, taking the list of items to ignore from the desktop's selection. void SnapManager::setupIgnoreSelection(SPDesktop const *desktop, bool snapindicator, std::vector *unselected_nodes, SPGuide *guide_to_ignore) { g_assert(desktop != NULL); if (_desktop != NULL) { // Someone has been naughty here! This is dangerous g_warning("The snapmanager has been set up before, but unSetup() hasn't been called afterwards. It possibly held invalid pointers"); } _desktop = desktop; _snapindicator = snapindicator; _unselected_nodes = unselected_nodes; _guide_to_ignore = guide_to_ignore; _rotation_center_source_items = NULL; _items_to_ignore.clear(); Inkscape::Selection *sel = _desktop->selection; GSList const *items = sel->itemList(); for (GSList *i = const_cast(items); i; i = i->next) { _items_to_ignore.push_back(static_cast(i->data)); } } SPDocument *SnapManager::getDocument() const { return _named_view->document; } Geom::Point SnapManager::_transformPoint(Inkscape::SnapCandidatePoint 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 TRANSLATE: transformed = p.getPoint() + transformation; break; case SCALE: transformed = (p.getPoint() - 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.getPoint() - origin) * s) + origin; break; } case SKEW: // Apply the skew factor transformed[dim] = (p.getPoint())[dim] + transformation[0] * ((p.getPoint())[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.getPoint() - origin)[1 - dim] * transformation[1] + origin[1 - dim]; break; case ROTATE: // for rotations: transformation[0] stores the angle in radians transformed = (p.getPoint() - origin) * Geom::Rotate(transformation[0]) + origin; break; default: g_assert_not_reached(); } return transformed; } /** * 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::SnapCandidatePoint const &p) const { Inkscape::Preferences *prefs = Inkscape::Preferences::get(); if (prefs->getBool("/options/snapclosestonly/value")) { Inkscape::SnapSourceType t = p.getSourceType(); bool p_is_a_node = t & Inkscape::SNAPSOURCE_NODE_CATEGORY; bool p_is_a_bbox = t & Inkscape::SNAPSOURCE_BBOX_CATEGORY; bool p_is_other = (t & Inkscape::SNAPSOURCE_OTHERS_CATEGORY) || (t & Inkscape::SNAPSOURCE_DATUMS_CATEGORY); g_assert(_desktop != NULL); if (snapprefs.getSnapEnabledGlobally() && (p_is_other || (p_is_a_node && snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_NODE_CATEGORY)) || (p_is_a_bbox && snapprefs.isTargetSnappable(Inkscape::SNAPTARGET_BBOX_CATEGORY)))) { _desktop->snapindicator->set_new_snapsource(p); } else { _desktop->snapindicator->remove_snapsource(); } } } /* Local Variables: mode:c++ c-file-style:"stroustrup" c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) indent-tabs-mode:nil fill-column:99 End: */ // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :