Ejemplo n.º 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
                    }
                }
            }
        }
    }
}
void Inkscape::LineSnapper::freeSnap(SnappedConstraints &sc,
                                                    Inkscape::SnapPreferences::PointType const &t,
                                                    Geom::Point const &p,
                                                    bool const &/*f*/,
                                                    Geom::OptRect const &/*bbox_to_snap*/,
                                                    std::vector<SPItem const *> const */*it*/,
                                                    std::vector<Geom::Point> */*unselected_nodes*/) const
{
	if (_snap_enabled == false || _snapmanager->snapprefs.getSnapFrom(t) == false) {
        return;
    }

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

    // std::cout << "snap point " << p << " to: " << std::endl;

    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 = project_on_linesegment(p, p1, p2);
        Geom::Coord const dist = Geom::L2(p_proj - p);
        //Store any line that's within snapping range
        if (dist < getSnapperTolerance()) {
            _addSnappedLine(sc, p_proj, dist, i->first, i->second);
            // std::cout << " -> distance = " << dist;
        }
        // std::cout << std::endl;
    }
}
Ejemplo n.º 3
0
void Inkscape::ObjectSnapper::_snapTranslatingGuide(IntermSnapResults &isr,
                                         Geom::Point const &p,
                                         Geom::Point const &guide_normal) const
{
    // Iterate through all nodes, find out which one is the closest to this guide, and snap to it!
    _collectNodes(SNAPSOURCE_GUIDE, true);

    if (_snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_PATH, SNAPTARGET_PATH_INTERSECTION, SNAPTARGET_BBOX_EDGE, SNAPTARGET_PAGE_BORDER, SNAPTARGET_TEXT_BASELINE)) {
        _collectPaths(p, SNAPSOURCE_GUIDE, true);
        _snapPaths(isr, SnapCandidatePoint(p, SNAPSOURCE_GUIDE), NULL, NULL);
    }

    SnappedPoint s;

    Geom::Coord tol = getSnapperTolerance();

    for (std::vector<SnapCandidatePoint>::const_iterator k = _points_to_snap_to->begin(); k != _points_to_snap_to->end(); ++k) {
        Geom::Point target_pt = (*k).getPoint();
        // Project each node (*k) on the guide line (running through point p)
        Geom::Point p_proj = Geom::projection(target_pt, Geom::Line(p, p + Geom::rot90(guide_normal)));
        Geom::Coord dist = Geom::L2(target_pt - p_proj); // distance from node to the guide
        Geom::Coord dist2 = Geom::L2(p - p_proj); // distance from projection of node on the guide, to the mouse location
        if ((dist < tol && dist2 < tol) || getSnapperAlwaysSnap()) {
            s = SnappedPoint(target_pt, SNAPSOURCE_GUIDE, 0, (*k).getTargetType(), dist, tol, getSnapperAlwaysSnap(), false, true, (*k).getTargetBBox());
            isr.points.push_back(s);
        }
    }
}
Ejemplo n.º 4
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(SnappedConstraints &sc,
                                               Inkscape::SnapPreferences::PointType const &t,
                                               Geom::Point const &p,
                                               bool const &/*f*/,
                                               Geom::OptRect const &/*bbox_to_snap*/,
                                               ConstraintLine const &c,
                                               std::vector<SPItem const *> const */*it*/) const

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

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

    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
            /* Normal to the line we're trying to snap along */
            Geom::Point const n(Geom::rot90(Geom::unit_vector(c.getDirection())));

            Geom::Point const point_on_line = c.hasPoint() ? c.getPoint() : p;

            /* Constant term of the line we're trying to snap along */
            Geom::Coord const q0 = dot(n, point_on_line);
            /* Constant term of the grid or guide line */
            Geom::Coord const q1 = dot(i->first, i->second);

            /* Try to intersect this line with the target line */
            Geom::Point t_2geom(NR_HUGE, NR_HUGE);
            Geom::IntersectorKind const k = Geom::line_intersection(n, q0, i->first, q1, t_2geom);
            Geom::Point t(t_2geom);

            if (k == Geom::intersects) {
                const Geom::Coord dist = L2(t - p);
                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
                    sc.points.push_back(SnappedPoint(t, Inkscape::SNAPTARGET_UNDEFINED, dist, getSnapperTolerance(), getSnapperAlwaysSnap(), true));
                    // The type of the snap target is yet undefined, as we cannot tell whether
                    // we're snapping to grid or the guide lines; must be set by on a higher level
                }
            }
        }
    }
}
Ejemplo n.º 6
0
void Inkscape::ObjectSnapper::_snapNodes(IntermSnapResults &isr,
                                         SnapCandidatePoint const &p,
                                         std::vector<SnapCandidatePoint> *unselected_nodes,
                                         SnapConstraint const &c,
                                         Geom::Point const &p_proj_on_constraint) const
{
    // Iterate through all nodes, find out which one is the closest to p, and snap to it!

    _collectNodes(p.getSourceType(), p.getSourceNum() <= 0);

    if (unselected_nodes != NULL && unselected_nodes->size() > 0) {
        g_assert(_points_to_snap_to != NULL);
        _points_to_snap_to->insert(_points_to_snap_to->end(), unselected_nodes->begin(), unselected_nodes->end());
    }

    SnappedPoint s;
    bool success = false;
    bool strict_snapping = _snapmanager->snapprefs.getStrictSnapping();

    for (std::vector<SnapCandidatePoint>::const_iterator k = _points_to_snap_to->begin(); k != _points_to_snap_to->end(); ++k) {
        if (_allowSourceToSnapToTarget(p.getSourceType(), (*k).getTargetType(), strict_snapping)) {
            Geom::Point target_pt = (*k).getPoint();
            Geom::Coord dist = Geom::infinity();
            if (!c.isUndefined()) {
                // We're snapping to nodes along a constraint only, so find out if this node
                // is at the constraint, while allowing for a small margin
                if (Geom::L2(target_pt - c.projection(target_pt)) > 1e-9) {
                    // The distance from the target point to its projection on the constraint
                    // is too large, so this point is not on the constraint. Skip it!
                    continue;
                }
                dist = Geom::L2(target_pt - p_proj_on_constraint);
            } else {
                // Free (unconstrained) snapping
                dist = Geom::L2(target_pt - p.getPoint());
            }

            if (dist < getSnapperTolerance() && dist < s.getSnapDistance()) {
                s = SnappedPoint(target_pt, p.getSourceType(), p.getSourceNum(), (*k).getTargetType(), dist, getSnapperTolerance(), getSnapperAlwaysSnap(), false, true, (*k).getTargetBBox());
                success = true;
            }
        }
    }

    if (success) {
        isr.points.push_back(s);
    }
}
Ejemplo n.º 7
0
void Inkscape::GuideSnapper::_addSnappedPoint(IntermSnapResults &isr, Geom::Point const &snapped_point, Geom::Coord const &snapped_distance, SnapSourceType const &source, long source_num, bool constrained_snap) const
{
    SnappedPoint dummy = SnappedPoint(snapped_point, source, source_num, Inkscape::SNAPTARGET_GUIDE, snapped_distance, getSnapperTolerance(), getSnapperAlwaysSnap(), constrained_snap, true);
    isr.points.push_back(dummy);
}
Ejemplo n.º 8
0
void Inkscape::GuideSnapper::_addSnappedLine(IntermSnapResults &isr, Geom::Point const &snapped_point, Geom::Coord const &snapped_distance, SnapSourceType const &source, long source_num, Geom::Point const &normal_to_line, Geom::Point const &point_on_line) const
{
    SnappedLine dummy = SnappedLine(snapped_point, snapped_distance, source, source_num, Inkscape::SNAPTARGET_GUIDE, getSnapperTolerance(), getSnapperAlwaysSnap(), normal_to_line, point_on_line);
    isr.guide_lines.push_back(dummy);
}
Ejemplo n.º 9
0
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);
                }
            }
        }
    }
}
Ejemplo n.º 10
0
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;
    }
}
Ejemplo n.º 11
0
void Inkscape::ObjectSnapper::_snapPathsTangPerp(bool snap_tang, bool snap_perp, IntermSnapResults &isr, SnapCandidatePoint const &p, Geom::Curve const *curve, SPDesktop const *dt) const
{
    // Here we will try to snap either tangentially or perpendicularly to a single path; for this we need to know where the origin is located of the line that is currently being rotated,
    // or we need to know the vector of the guide which is currently being translated
    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) {
        Geom::Point origin_or_vector_doc = dt->dt2doc((*it_origin_or_vector).first); // "first" contains a Geom::Point, denoting either a point or vector
        if ((*it_origin_or_vector).second) { // if "second" is true then "first" is a vector, otherwise it's a point
            // So we have a vector, which tells us what tangential or perpendicular direction we're looking for
            if (curve->degreesOfFreedom() <= 2) { // A LineSegment has order one, and therefore 2 DOF
                // When snapping to a point of a line segment that has a specific tangential or normal vector, then either all point
                // along that line will be snapped to or no points at all will be snapped to. This is not very useful, so let's skip
                // any line segments and lets only snap to higher order curves
                continue;
            }
            // The vector is being treated as a point (relative to the origin), and has been translated to document coordinates accordingly
            // We need however to make it a vector again, because also the origin has been transformed
            origin_or_vector_doc -= dt->dt2doc(Geom::Point(0,0));
        }

        Geom::Point point_dt;
        Geom::Coord dist;
        std::vector<double> ts;

        if (snap_tang) { // Find all points that lead to a tangential snap
            if ((*it_origin_or_vector).second) { // if "second" is true then "first" is a vector, otherwise it's a point
                ts = find_tangents_by_vector(origin_or_vector_doc, curve->toSBasis());
            } else {
                ts = find_tangents(origin_or_vector_doc, curve->toSBasis());
            }
            for (std::vector<double>::const_iterator t = ts.begin(); t != ts.end(); ++t) {
                point_dt = dt->doc2dt(curve->pointAt(*t));
                dist = Geom::distance(point_dt, p.getPoint());
                isr.points.push_back(SnappedPoint(point_dt, p.getSourceType(), p.getSourceNum(), SNAPTARGET_PATH_TANGENTIAL, dist, getSnapperTolerance(), getSnapperAlwaysSnap(), false, true));
            }
        }

        if (snap_perp) { // Find all points that lead to a perpendicular snap
            if ((*it_origin_or_vector).second) {
                ts = find_normals_by_vector(origin_or_vector_doc, curve->toSBasis());
            } else {
                ts = find_normals(origin_or_vector_doc, curve->toSBasis());
            }
            for (std::vector<double>::const_iterator t = ts.begin(); t != ts.end(); ++t) {
                point_dt = dt->doc2dt(curve->pointAt(*t));
                dist = Geom::distance(point_dt, p.getPoint());
                isr.points.push_back(SnappedPoint(point_dt, p.getSourceType(), p.getSourceNum(), SNAPTARGET_PATH_PERPENDICULAR, dist, getSnapperTolerance(), getSnapperAlwaysSnap(), false, true));
            }
        }
    }
}
Ejemplo n.º 12
0
void Inkscape::ObjectSnapper::_findCandidates(SPObject* parent,
                                              std::vector<SPItem const *> const *it,
                                              bool const &first_point,
                                              Geom::Rect const &bbox_to_snap,
                                              bool const clip_or_mask,
                                              Geom::Affine const additional_affine) const // transformation of the item being clipped / masked
{
    SPDesktop const *dt = _snapmanager->getDesktop();
    if (dt == NULL) {
        g_warning("desktop == NULL, so we cannot snap; please inform the developers of this bug");
        // Apparently the setup() method from the SnapManager class hasn't been called before trying to snap.
    }

    if (first_point) {
        _candidates->clear();
    }

    Geom::Rect bbox_to_snap_incl = bbox_to_snap; // _incl means: will include the snapper tolerance
    bbox_to_snap_incl.expandBy(getSnapperTolerance()); // see?

    for ( SPObject *o = parent->firstChild(); o; o = o->getNext() ) {
        g_assert(dt != NULL);
        if (SP_IS_ITEM(o) && !(dt->itemIsHidden(SP_ITEM(o)) && !clip_or_mask)) {
            // Snapping to items in a locked layer is allowed
            // Don't snap to hidden objects, unless they're a clipped path or a mask
            /* See if this item is on the ignore list */
            std::vector<SPItem const *>::const_iterator i;
            if (it != NULL) {
                i = it->begin();
                while (i != it->end() && *i != o) {
                    ++i;
                }
            }

            if (it == NULL || i == it->end()) {
                SPItem *item = SP_ITEM(o);
                if (item) {
                    if (!clip_or_mask) { // cannot clip or mask more than once
                        // The current item is not a clipping path or a mask, but might
                        // still be the subject of clipping or masking itself ; if so, then
                        // we should also consider that path or mask for snapping to
                        SPObject *obj = SP_OBJECT(item->clip_ref ? item->clip_ref->getObject() : NULL);
                        if (obj && _snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_PATH_CLIP)) {
                            _findCandidates(obj, it, false, bbox_to_snap, true, item->i2doc_affine());
                        }
                        obj = SP_OBJECT(item->mask_ref ? item->mask_ref->getObject() : NULL);
                        if (obj && _snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_PATH_MASK)) {
                            _findCandidates(obj, it, false, bbox_to_snap, true, item->i2doc_affine());
                        }
                    }
                }

                if (SP_IS_GROUP(o)) {
                    _findCandidates(o, it, false, bbox_to_snap, clip_or_mask, additional_affine);
                } else {
                    Geom::OptRect bbox_of_item;
                    Preferences *prefs = Preferences::get();
                    int prefs_bbox = prefs->getBool("/tools/bounding_box", 0);
                    // We'll only need to obtain the visual bounding box if the user preferences tell
                    // us to, AND if we are snapping to the bounding box itself. If we're snapping to
                    // paths only, then we can just as well use the geometric bounding box (which is faster)
                    SPItem::BBoxType bbox_type = (!prefs_bbox && _snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_BBOX_CATEGORY)) ?
                        SPItem::VISUAL_BBOX : SPItem::GEOMETRIC_BBOX;
                    if (clip_or_mask) {
                        // Oh oh, this will get ugly. We cannot use sp_item_i2d_affine directly because we need to
                        // insert an additional transformation in document coordinates (code copied from sp_item_i2d_affine)
                        bbox_of_item = item->bounds(bbox_type, item->i2doc_affine() * additional_affine * dt->doc2dt());
                    } else {
                        bbox_of_item = item->desktopBounds(bbox_type);
                    }
                    if (bbox_of_item) {
                        // See if the item is within range
                        if (bbox_to_snap_incl.intersects(*bbox_of_item)
                                || (_snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_ROTATION_CENTER) && bbox_to_snap_incl.contains(item->getCenter()))) { // rotation center might be outside of the bounding box
                            // This item is within snapping range, so record it as a candidate
                            _candidates->push_back(SnapCandidateItem(item, clip_or_mask, additional_affine));
                            // For debugging: print the id of the candidate to the console
                            // SPObject *obj = (SPObject*)item;
                            // std::cout << "Snap candidate added: " << obj->getId() << std::endl;
                        }
                    }
                }
            }
        }
    }
}
Ejemplo n.º 13
0
void Inkscape::ObjectSnapper::_snapPathsConstrained(IntermSnapResults &isr,
                                     SnapCandidatePoint const &p,
                                     SnapConstraint const &c,
                                     Geom::Point const &p_proj_on_constraint) const
{

    _collectPaths(p_proj_on_constraint, p.getSourceType(), p.getSourceNum() <= 0);

    // Now we can finally do the real snapping, using the paths collected above

    SPDesktop const *dt = _snapmanager->getDesktop();
    g_assert(dt != NULL);

    Geom::Point direction_vector = c.getDirection();
    if (!is_zero(direction_vector)) {
        direction_vector = Geom::unit_vector(direction_vector);
    }

    // The intersection point of the constraint line with any path, must lie within two points on the
    // SnapConstraint: p_min_on_cl and p_max_on_cl. The distance between those points is twice the snapping tolerance
    Geom::Point const p_min_on_cl = dt->dt2doc(p_proj_on_constraint - getSnapperTolerance() * direction_vector);
    Geom::Point const p_max_on_cl = dt->dt2doc(p_proj_on_constraint + getSnapperTolerance() * direction_vector);
    Geom::Coord tolerance = getSnapperTolerance();

    // PS: Because the paths we're about to snap to are all expressed relative to document coordinate system, we will have
    // to convert the snapper coordinates from the desktop coordinates to document coordinates

    std::vector<Geom::Path> constraint_path;
    if (c.isCircular()) {
        Geom::Circle constraint_circle(dt->dt2doc(c.getPoint()), c.getRadius());
        constraint_circle.getPath(constraint_path);
    } else {
        Geom::Path constraint_line;
        constraint_line.start(p_min_on_cl);
        constraint_line.appendNew<Geom::LineSegment>(p_max_on_cl);
        constraint_path.push_back(constraint_line);
    }
    // Length of constraint_path will always be one

    bool strict_snapping = _snapmanager->snapprefs.getStrictSnapping();

    // Find all intersections of the constrained path with the snap target candidates
    std::vector<Geom::Point> intersections;
    for (std::vector<SnapCandidatePath >::const_iterator k = _paths_to_snap_to->begin(); k != _paths_to_snap_to->end(); ++k) {
        if (k->path_vector && _allowSourceToSnapToTarget(p.getSourceType(), (*k).target_type, strict_snapping)) {
            // Do the intersection math
            Geom::CrossingSet cs = Geom::crossings(constraint_path, *(k->path_vector));
            // Store the results as intersection points
            unsigned int index = 0;
            for (Geom::CrossingSet::const_iterator i = cs.begin(); i != cs.end(); ++i) {
                if (index >= constraint_path.size()) {
                    break;
                }
                // Reconstruct and store the points of intersection
                for (Geom::Crossings::const_iterator m = (*i).begin(); m != (*i).end(); ++m) {
                    intersections.push_back(constraint_path[index].pointAt((*m).ta));
                }
                index++;
            }

            //Geom::crossings will not consider the closing segment apparently, so we'll handle that separately here
            //TODO: This should have been fixed in rev. #9859, which makes this workaround obsolete
            for(Geom::PathVector::iterator it_pv = k->path_vector->begin(); it_pv != k->path_vector->end(); ++it_pv) {
                if (it_pv->closed()) {
                    // Get the closing linesegment and convert it to a path
                    Geom::Path cls;
                    cls.close(false);
                    cls.append(it_pv->back_closed());
                    // Intersect that closing path with the constrained path
                    Geom::Crossings cs = Geom::crossings(constraint_path.front(), cls);
                    // Reconstruct and store the points of intersection
                    index = 0; // assuming the constraint path vector has only one path
                    for (Geom::Crossings::const_iterator m = cs.begin(); m != cs.end(); ++m) {
                        intersections.push_back(constraint_path[index].pointAt((*m).ta));
                    }
                }
            }

            // Convert the collected points of intersection to snapped points
            for (std::vector<Geom::Point>::iterator p_inters = intersections.begin(); p_inters != intersections.end(); ++p_inters) {
                // Convert to desktop coordinates
                (*p_inters) = dt->doc2dt(*p_inters);
                // Construct a snapped point
                Geom::Coord dist = Geom::L2(p.getPoint() - *p_inters);
                SnappedPoint s = SnappedPoint(*p_inters, p.getSourceType(), p.getSourceNum(), k->target_type, dist, getSnapperTolerance(), getSnapperAlwaysSnap(), true, k->target_bbox);;
                // Store the snapped point
                if (dist <= tolerance) { // If the intersection is within snapping range, then we might snap to it
                    isr.points.push_back(s);
                }
            }
        }
    }
}
Ejemplo n.º 14
0
void Inkscape::ObjectSnapper::_snapPaths(IntermSnapResults &isr,
                                     SnapCandidatePoint const &p,
                                     std::vector<SnapCandidatePoint> *unselected_nodes,
                                     SPPath const *selected_path) const
{
    _collectPaths(p.getPoint(), p.getSourceType(), p.getSourceNum() <= 0);
    // Now we can finally do the real snapping, using the paths collected above

    SPDesktop const *dt = _snapmanager->getDesktop();
    g_assert(dt != NULL);
    Geom::Point const p_doc = dt->dt2doc(p.getPoint());

    bool const node_tool_active = _snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_PATH, SNAPTARGET_PATH_INTERSECTION) && selected_path != NULL;

    if (p.getSourceNum() <= 0) {
        /* findCandidates() is used for snapping to both paths and nodes. It ignores the path that is
         * currently being edited, because that path requires special care: when snapping to nodes
         * only the unselected nodes of that path should be considered, and these will be passed on separately.
         * This path must not be ignored however when snapping to the paths, so we add it here
         * manually when applicable.
         * */
        if (node_tool_active) {
            // TODO fix the function to be const correct:
            SPCurve *curve = curve_for_item(const_cast<SPPath*>(selected_path));
            if (curve) {
                Geom::PathVector *pathv = pathvector_for_curve(const_cast<SPPath*>(selected_path),
                                                               curve,
                                                               true,
                                                               true,
                                                               Geom::identity(),
                                                               Geom::identity()); // We will get our own copy of the path, which must be freed at some point
                _paths_to_snap_to->push_back(SnapCandidatePath(pathv, SNAPTARGET_PATH, Geom::OptRect(), true));
                curve->unref();
            }
        }
    }

    int num_path = 0; // _paths_to_snap_to contains multiple path_vectors, each containing multiple paths.
                      // num_path will count the paths, and will not be zeroed for each path_vector. It will
                      // continue counting

    bool strict_snapping = _snapmanager->snapprefs.getStrictSnapping();
    bool snap_perp = _snapmanager->snapprefs.getSnapPerp();
    bool snap_tang = _snapmanager->snapprefs.getSnapTang();

    //dt->snapindicator->remove_debugging_points();
    for (std::vector<SnapCandidatePath >::const_iterator it_p = _paths_to_snap_to->begin(); it_p != _paths_to_snap_to->end(); ++it_p) {
        if (_allowSourceToSnapToTarget(p.getSourceType(), (*it_p).target_type, strict_snapping)) {
            bool const being_edited = node_tool_active && (*it_p).currently_being_edited;
            //if true then this pathvector it_pv is currently being edited in the node tool

            for(Geom::PathVector::iterator it_pv = (it_p->path_vector)->begin(); it_pv != (it_p->path_vector)->end(); ++it_pv) {
                // Find a nearest point for each curve within this path
                // n curves will return n time values with 0 <= t <= 1
                std::vector<double> anp = (*it_pv).nearestPointPerCurve(p_doc);

                //std::cout << "#nearest points = " << anp.size() << " | p = " << p.getPoint() << std::endl;
                // Now we will examine each of the nearest points, and determine whether it's within snapping range and if we should snap to it
                std::vector<double>::const_iterator np = anp.begin();
                unsigned int index = 0;
                for (; np != anp.end(); ++np, index++) {
                    Geom::Curve const *curve = &((*it_pv).at_index(index));
                    Geom::Point const sp_doc = curve->pointAt(*np);
                    //dt->snapindicator->set_new_debugging_point(sp_doc*dt->doc2dt());
                    bool c1 = true;
                    bool c2 = true;
                    if (being_edited) {
                        /* If the path is being edited, then we should only snap though to stationary pieces of the path
                         * and not to the pieces that are being dragged around. This way we avoid
                         * self-snapping. For this we check whether the nodes at both ends of the current
                         * piece are unselected; if they are then this piece must be stationary
                         */
                        g_assert(unselected_nodes != NULL);
                        Geom::Point start_pt = dt->doc2dt(curve->pointAt(0));
                        Geom::Point end_pt = dt->doc2dt(curve->pointAt(1));
                        c1 = isUnselectedNode(start_pt, unselected_nodes);
                        c2 = isUnselectedNode(end_pt, unselected_nodes);
                        /* Unfortunately, this might yield false positives for coincident nodes. Inkscape might therefore mistakenly
                         * snap to path segments that are not stationary. There are at least two possible ways to overcome this:
                         * - Linking the individual nodes of the SPPath we have here, to the nodes of the NodePath::SubPath class as being
                         *   used in sp_nodepath_selected_nodes_move. This class has a member variable called "selected". For this the nodes
                         *   should be in the exact same order for both classes, so we can index them
                         * - Replacing the SPPath being used here by the NodePath::SubPath class; but how?
                         */
                    }

                    Geom::Point const sp_dt = dt->doc2dt(sp_doc);
                    if (!being_edited || (c1 && c2)) {
                        Geom::Coord dist = Geom::distance(sp_doc, p_doc);
                        // std::cout << "  dist -> " << dist << std::endl;
                        if (dist < getSnapperTolerance()) {
                            // Add the curve we have snapped to
                            Geom::Point sp_tangent_dt = Geom::Point(0,0);
                            if (p.getSourceType() == Inkscape::SNAPSOURCE_GUIDE_ORIGIN) {
                                // We currently only use the tangent when snapping guides, so only in this case we will
                                // actually calculate the tangent to avoid wasting CPU cycles
                                Geom::Point sp_tangent_doc = curve->unitTangentAt(*np);
                                sp_tangent_dt = dt->doc2dt(sp_tangent_doc) - dt->doc2dt(Geom::Point(0,0));
                            }
                            isr.curves.push_back(SnappedCurve(sp_dt, sp_tangent_dt, num_path, index, dist, getSnapperTolerance(), getSnapperAlwaysSnap(), false, curve, p.getSourceType(), p.getSourceNum(), it_p->target_type, it_p->target_bbox));
                            if (snap_tang || snap_perp) {
                                // For each curve that's within snapping range, we will now also search for tangential and perpendicular snaps
                                _snapPathsTangPerp(snap_tang, snap_perp, isr, p, curve, dt);
                            }
                        }
                    }
                }
                num_path++;
            } // End of: for (Geom::PathVector::iterator ....)
        }
    }
}