Exemple #1
0
void Inkscape::LineSnapper::constrainedSnap(SnappedConstraints &sc,
                                               Inkscape::SnapCandidatePoint const &p,
                                               Geom::OptRect const &/*bbox_to_snap*/,
                                               ConstraintLine const &c,
                                               std::vector<SPItem const *> const */*it*/) const

{
    if (_snap_enabled == false || _snapmanager->snapprefs.getSnapFrom(p.getSourceType()) == false) {
        return;
    }

    /* Get the lines that we will try to snap to */
    const LineList lines = _getSnapLines(p.getPoint());

    for (LineList::const_iterator i = lines.begin(); i != lines.end(); i++) {
        if (Geom::L2(c.getDirection()) > 0) { // Can't do a constrained snap without a constraint
            // constraint line
            Geom::Point const point_on_line = c.hasPoint() ? c.getPoint() : p.getPoint();
            Geom::Line line1(point_on_line, point_on_line + c.getDirection());

            // grid/guide line
            Geom::Point const p1 = i->second; // point at guide/grid line
            Geom::Point const p2 = p1 + Geom::rot90(i->first); // 2nd point at guide/grid line
            Geom::Line line2(p1, p2);

            Geom::OptCrossing inters = Geom::OptCrossing(); // empty by default
            try
            {
                inters = Geom::intersection(line1, line2);
            }
            catch (Geom::InfiniteSolutions e)
            {
                // We're probably dealing with parallel lines, so snapping doesn't make any sense here
                continue; // jump to the next iterator in the for-loop
            }

            if (inters) {
                Geom::Point t = line1.pointAt((*inters).ta);
                const Geom::Coord dist = Geom::L2(t - p.getPoint());
                if (dist < getSnapperTolerance()) {
                    // When doing a constrained snap, we're already at an intersection.
                    // This snappoint is therefore fully constrained, so there's no need
                    // to look for additional intersections; just return the snapped point
                    // and forget about the line
                    _addSnappedPoint(sc, t, dist, p.getSourceType(), p.getSourceNum(), true);
                    // For any line that's within range, we will also look at it's "point on line" p1. For guides
                    // this point coincides with its origin; for grids this is of no use, but we cannot
                    // discern between grids and guides here
                    Geom::Coord const dist_p1 = Geom::L2(p1 - p.getPoint());
                    if (dist_p1 < getSnapperTolerance()) {
                        _addSnappedLinesOrigin(sc, p1, dist_p1, p.getSourceType(), p.getSourceNum(), true);
                        // Only relevant for guides; grids don't have an origin per line
                        // Therefore _addSnappedLinesOrigin() will only be implemented for guides
                    }
                }
            }
        }
    }
}
Exemple #2
0
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;
}
Exemple #3
0
Inkscape::SnappedPoint SnapManager::constrainedAngularSnap(Inkscape::SnapCandidatePoint const &p,
                                                            boost::optional<Geom::Point> 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<Inkscape::Snapper::SnapConstraint> 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;
}
Exemple #4
0
/**
 * 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();
        }
    }
}
Exemple #5
0
void Inkscape::LineSnapper::freeSnap(SnappedConstraints &sc,
                                                    Inkscape::SnapCandidatePoint const &p,
                                                    Geom::OptRect const &/*bbox_to_snap*/,
                                                    std::vector<SPItem const *> const */*it*/,
                                                    std::vector<Inkscape::SnapCandidatePoint> */*unselected_nodes*/) const
{
    if (!(_snap_enabled && _snapmanager->snapprefs.getSnapFrom(p.getSourceType())) ) {
        return;
    }

    /* Get the lines that we will try to snap to */
    const LineList lines = _getSnapLines(p.getPoint());

    for (LineList::const_iterator i = lines.begin(); i != lines.end(); i++) {
        Geom::Point const p1 = i->second; // point at guide/grid line
        Geom::Point const p2 = p1 + Geom::rot90(i->first); // 2nd point at guide/grid line
        // std::cout << "  line through " << i->second << " with normal " << i->first;
        g_assert(i->first != Geom::Point(0,0)); // we cannot project on an linesegment of zero length

        Geom::Point const p_proj = Geom::projection(p.getPoint(), Geom::Line(p1, p2));
        Geom::Coord const dist = Geom::L2(p_proj - p.getPoint());
        //Store any line that's within snapping range
        if (dist < getSnapperTolerance()) {
            _addSnappedLine(sc, p_proj, dist, p.getSourceType(), p.getSourceNum(), i->first, i->second);
            // For any line that's within range, we will also look at it's "point on line" p1. For guides
            // this point coincides with its origin; for grids this is of no use, but we cannot
            // discern between grids and guides here
            Geom::Coord const dist_p1 = Geom::L2(p1 - p.getPoint());
            if (dist_p1 < getSnapperTolerance()) {
                _addSnappedLinesOrigin(sc, p1, dist_p1, p.getSourceType(), p.getSourceNum(), false);
                // Only relevant for guides; grids don't have an origin per line
                // Therefore _addSnappedLinesOrigin() will only be implemented for guides
            }
            // std::cout << " -> distance = " << dist;
        }
        // std::cout << std::endl;
    }
}
void Inkscape::LineSnapper::constrainedSnap(IntermSnapResults &isr,
                                               Inkscape::SnapCandidatePoint const &p,
                                               Geom::OptRect const &/*bbox_to_snap*/,
                                               SnapConstraint const &c,
                                               std::vector<SPItem const *> const */*it*/,
                                               std::vector<SnapCandidatePoint> */*unselected_nodes*/) const

{
    if (_snap_enabled == false || _snapmanager->snapprefs.isSourceSnappable(p.getSourceType()) == false) {
        return;
    }

    // project the mouse pointer onto the constraint. Only the projected point will be considered for snapping
    Geom::Point pp = c.projection(p.getPoint());

    /* Get the lines that we will try to snap to */
    const LineList lines = _getSnapLines(pp);

    for (LineList::const_iterator i = lines.begin(); i != lines.end(); ++i) {
        Geom::Point const point_on_line = c.hasPoint() ? c.getPoint() : pp;
        Geom::Line gridguide_line(i->second, i->second + Geom::rot90(i->first));

        if (c.isCircular()) {
            // Find the intersections between the line and the circular constraint
            // First, project the origin of the circle onto the line
            Geom::Point const origin = c.getPoint();
            Geom::Point const p_proj = Geom::projection(origin, gridguide_line);
            Geom::Coord dist = Geom::L2(p_proj - origin); // distance from circle origin to constraint line
            Geom::Coord radius = c.getRadius();
            if (dist == radius) {
                // Only one point of intersection;
                _addSnappedPoint(isr, p_proj, Geom::L2(pp - p_proj), p.getSourceType(), p.getSourceNum(), true);
            } else if (dist < radius) {
                // Two points of intersection, symmetrical with respect to the projected point
                // Calculate half the length of the linesegment between the two points of intersection
                Geom::Coord l = sqrt(radius*radius - dist*dist);
                Geom::Coord d = Geom::L2(gridguide_line.versor()); // length of versor, needed to normalize the versor
                if (d > 0) {
                    Geom::Point v = l*gridguide_line.versor()/d;
                    _addSnappedPoint(isr, p_proj + v, Geom::L2(p.getPoint() - (p_proj + v)), p.getSourceType(), p.getSourceNum(), true);
                    _addSnappedPoint(isr, p_proj - v, Geom::L2(p.getPoint() - (p_proj - v)), p.getSourceType(), p.getSourceNum(), true);
                }
            }
        } else {
            // Find the intersections between the line and the linear constraint
            Geom::Line constraint_line(point_on_line, point_on_line + c.getDirection());
            Geom::OptCrossing inters = Geom::OptCrossing(); // empty by default
            try
            {
                inters = Geom::intersection(constraint_line, gridguide_line);
            }
            catch (Geom::InfiniteSolutions &e)
            {
                // We're probably dealing with parallel lines, so snapping doesn't make any sense here
                continue; // jump to the next iterator in the for-loop
            }

            if (inters) {
                Geom::Point t = constraint_line.pointAt((*inters).ta);
                const Geom::Coord dist = Geom::L2(t - p.getPoint());
                if (dist < getSnapperTolerance()) {
                    // When doing a constrained snap, we're already at an intersection.
                    // This snappoint is therefore fully constrained, so there's no need
                    // to look for additional intersections; just return the snapped point
                    // and forget about the line
                    _addSnappedPoint(isr, t, dist, p.getSourceType(), p.getSourceNum(), true);
                }
            }
        }
    }
}
void Inkscape::LineSnapper::freeSnap(IntermSnapResults &isr,
                                                    Inkscape::SnapCandidatePoint const &p,
                                                    Geom::OptRect const &/*bbox_to_snap*/,
                                                    std::vector<SPItem const *> const */*it*/,
                                                    std::vector<Inkscape::SnapCandidatePoint> */*unselected_nodes*/) const
{
    if (!(_snap_enabled && _snapmanager->snapprefs.isSourceSnappable(p.getSourceType())) ) {
        return;
    }

    /* Get the lines that we will try to snap to */
    const LineList lines = _getSnapLines(p.getPoint());

    for (LineList::const_iterator i = lines.begin(); i != lines.end(); ++i) {
        Geom::Point const p1 = i->second; // point at guide/grid line
        Geom::Point const p2 = p1 + Geom::rot90(i->first); // 2nd point at guide/grid line
        // std::cout << "  line through " << i->second << " with normal " << i->first;
        assert(i->first != Geom::Point(0,0)); // we cannot project on an linesegment of zero length

        Geom::Point const p_proj = Geom::projection(p.getPoint(), Geom::Line(p1, p2));
        Geom::Coord const dist = Geom::L2(p_proj - p.getPoint());
        //Store any line that's within snapping range
        if (dist < getSnapperTolerance()) {
            _addSnappedLine(isr, p_proj, dist, p.getSourceType(), p.getSourceNum(), i->first, i->second);
            // For any line that's within range, we will also look at it's "point on line" p1. For guides
            // this point coincides with its origin; for grids this is of no use, but we cannot
            // discern between grids and guides here
            Geom::Coord const dist_p1 = Geom::L2(p1 - p.getPoint());
            if (dist_p1 < getSnapperTolerance()) {
                _addSnappedLinesOrigin(isr, p1, dist_p1, p.getSourceType(), p.getSourceNum(), false);
                // Only relevant for guides; grids don't have an origin per line
                // Therefore _addSnappedLinesOrigin() will only be implemented for guides
            }

            // Here we will try to snap either tangentially or perpendicularly to a grid/guide line
            // For this we need to know where the origin is located of the line that is currently being rotated,
            std::vector<std::pair<Geom::Point, bool> > const origins_and_vectors = p.getOriginsAndVectors();
            // Now we will iterate over all the origins and vectors and see which of these will get use a tangential or perpendicular snap
            for (std::vector<std::pair<Geom::Point, bool> >::const_iterator it_origin_or_vector = origins_and_vectors.begin(); it_origin_or_vector != origins_and_vectors.end(); ++it_origin_or_vector) {
                if ((*it_origin_or_vector).second) { // if "second" is true then "first" is a vector, otherwise it's a point
                    // When snapping a line with a constant vector (constant direction) to a guide or grid line,
                    // then either all points will be perpendicular/tangential or none at all. This is not very useful
                    continue;
                }

                //Geom::Point origin_doc = _snapmanager->getDesktop()->dt2doc((*it_origin_or_vector).first); // "first" contains a Geom::Point, denoting either a point
                Geom::Point origin = (*it_origin_or_vector).first; // "first" contains a Geom::Point, denoting either a point

                // We won't try to snap tangentially; a line being tangential to another line can be achieved by snapping both its endpoints
                // individually to the other line. There's no need to have an explicit tangential snap here, that would be redundant

                if (_snapmanager->snapprefs.getSnapPerp()) { // Find the point that leads to a perpendicular snap
                    Geom::Point const origin_proj = Geom::projection(origin, Geom::Line(p1, p2));
                    Geom::Coord dist = Geom::L2(origin_proj - p.getPoint());
                    if (dist < getSnapperTolerance()) {
                        _addSnappedLinePerpendicularly(isr, origin_proj, dist, p.getSourceType(), p.getSourceNum(), false);
                    }
                }
            }

            // std::cout << " -> distance = " << dist;
        }
        // std::cout << std::endl;
    }
}
Exemple #8
0
Inkscape::SnappedPoint SnapManager::findBestSnap(Inkscape::SnapCandidatePoint const &p,
                                                 IntermSnapResults const &isr,
                                                 bool constrained,
                                                 bool allowOffScreen,
                                                 bool to_path_only) 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<Inkscape::SnappedPoint>::const_iterator i = isr.points.begin(); i != isr.points.end(); i++) {
        _desktop->snapindicator->set_new_debugging_point((*i).getPoint());
    }
    for (std::list<Inkscape::SnappedCurve>::const_iterator i = isr.curves.begin(); i != isr.curves.end(); i++) {
        _desktop->snapindicator->set_new_debugging_point((*i).getPoint());
    }
    for (std::list<Inkscape::SnappedLine>::const_iterator i = isr.grid_lines.begin(); i != isr.grid_lines.end(); i++) {
        _desktop->snapindicator->set_new_debugging_point((*i).getPoint());
    }
    for (std::list<Inkscape::SnappedLine>::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<Inkscape::SnappedPoint> 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);
            }
        }
    }

    // Filter out all snap targets that do NOT include a path; this is useful when we try to insert
    // a node in a path (on doubleclick in the node tool). We don't want to change the shape of the
    // path, so the snapped point must be on a path, and not e.g. on a grid intersection
    if (to_path_only) {
        std::list<Inkscape::SnappedPoint>::iterator i = sp_list.begin();

        while (i != sp_list.end()) {
            Inkscape::SnapTargetType t = (*i).getTarget();
            if (t == Inkscape::SNAPTARGET_LINE_MIDPOINT ||
                t == Inkscape::SNAPTARGET_PATH ||
                t == Inkscape::SNAPTARGET_PATH_PERPENDICULAR ||
                t == Inkscape::SNAPTARGET_PATH_TANGENTIAL ||
                t == Inkscape::SNAPTARGET_PATH_INTERSECTION ||
                t == Inkscape::SNAPTARGET_PATH_GUIDE_INTERSECTION ||
                t == Inkscape::SNAPTARGET_PATH_CLIP ||
                t == Inkscape::SNAPTARGET_PATH_MASK ||
                t == Inkscape::SNAPTARGET_ELLIPSE_QUADRANT_POINT) {
                ++i;
            } else {
                i = sp_list.erase(i);
            }
        }
    }

    // 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<Inkscape::SnappedPoint>::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;
}
Exemple #9
0
Inkscape::SnappedPoint SnapManager::multipleConstrainedSnaps(Inkscape::SnapCandidatePoint const &p,
                                                    std::vector<Inkscape::Snapper::SnapConstraint> 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<Geom::Point> projections;
    for (std::vector<Inkscape::Snapper::SnapConstraint>::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<Inkscape::Snapper::SnapConstraint>::const_iterator c = constraints.begin();
    std::vector<Geom::Point>::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;
}