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Diffstat (limited to 'src/ui/tool/node.cpp')
| -rw-r--r-- | src/ui/tool/node.cpp | 1923 |
1 files changed, 1923 insertions, 0 deletions
diff --git a/src/ui/tool/node.cpp b/src/ui/tool/node.cpp new file mode 100644 index 0000000..57be0af --- /dev/null +++ b/src/ui/tool/node.cpp @@ -0,0 +1,1923 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Authors: + * Krzysztof Kosiński <tweenk.pl@gmail.com> + * Jon A. Cruz <jon@joncruz.org> + * + * Copyright (C) 2009 Authors + * Released under GNU GPL v2+, read the file 'COPYING' for more information. + */ + +#include <atomic> +#include <iostream> +#include <stdexcept> +#include <boost/utility.hpp> + +#include <glib/gi18n.h> +#include <gdk/gdkkeysyms.h> + +#include <2geom/bezier-utils.h> + +#include "desktop.h" +#include "multi-path-manipulator.h" +#include "snap.h" + +#include "display/control/canvas-item-group.h" +#include "display/control/canvas-item-curve.h" + +#include "ui/tool/control-point-selection.h" +#include "ui/tool/event-utils.h" +#include "ui/tool/path-manipulator.h" +#include "ui/tools/node-tool.h" +#include "ui/widget/canvas.h" + +namespace { + +Inkscape::CanvasItemCtrlType nodeTypeToCtrlType(Inkscape::UI::NodeType type) +{ + Inkscape::CanvasItemCtrlType result = Inkscape::CANVAS_ITEM_CTRL_TYPE_NODE_CUSP; + switch(type) { + case Inkscape::UI::NODE_SMOOTH: + result = Inkscape::CANVAS_ITEM_CTRL_TYPE_NODE_SMOOTH; + break; + case Inkscape::UI::NODE_AUTO: + result = Inkscape::CANVAS_ITEM_CTRL_TYPE_NODE_AUTO; + break; + case Inkscape::UI::NODE_SYMMETRIC: + result = Inkscape::CANVAS_ITEM_CTRL_TYPE_NODE_SYMETRICAL; + break; + case Inkscape::UI::NODE_CUSP: + default: + result = Inkscape::CANVAS_ITEM_CTRL_TYPE_NODE_CUSP; + break; + } + return result; +} + +/** + * @brief provides means to estimate float point rounding error due to serialization to svg + * + * Keeps cached value up to date with preferences option `/options/svgoutput/numericprecision` + * to avoid costly direct reads + * */ +class SvgOutputPrecisionWatcher : public Inkscape::Preferences::Observer { +public: + /// Returns absolute \a value`s rounding serialization error based on current preferences settings + static double error_of(double value) { + return value * instance().rel_error; + } + + void notify(const Inkscape::Preferences::Entry &new_val) override { + int digits = new_val.getIntLimited(6, 1, 16); + set_numeric_precision(digits); + } + +private: + SvgOutputPrecisionWatcher() : Observer("/options/svgoutput/numericprecision"), rel_error(1) { + Inkscape::Preferences::get()->addObserver(*this); + int digits = Inkscape::Preferences::get()->getIntLimited("/options/svgoutput/numericprecision", 6, 1, 16); + set_numeric_precision(digits); + } + + ~SvgOutputPrecisionWatcher() override { + Inkscape::Preferences::get()->removeObserver(*this); + } + /// Update cached value of relative error with number of significant digits + void set_numeric_precision(int digits) { + double relative_error = 0.5; // the error is half of last digit + while (digits > 0) { + relative_error /= 10; + digits--; + } + rel_error = relative_error; + } + + static SvgOutputPrecisionWatcher &instance() { + static SvgOutputPrecisionWatcher _instance; + return _instance; + } + + std::atomic<double> rel_error; /// Cached relative error +}; + +/// Returns absolute error of \a point as if serialized to svg with current preferences +double serializing_error_of(const Geom::Point &point) { + return SvgOutputPrecisionWatcher::error_of(point.length()); +} + +/** + * @brief Returns true if three points are collinear within current serializing precision + * + * The algorithm of collinearity check is explicitly used to calculate the check error. + * + * This function can be sufficiently reduced or even removed completely if `Geom::are_collinear` + * would declare it's check algorithm as part of the public API. + * + * */ +bool are_collinear_within_serializing_error(const Geom::Point &A, const Geom::Point &B, const Geom::Point &C) { + const double tolerance_factor = 10; // to account other factors which increase uncertainty + const double tolerance_A = serializing_error_of(A) * tolerance_factor; + const double tolerance_B = serializing_error_of(B) * tolerance_factor; + const double tolerance_C = serializing_error_of(C) * tolerance_factor; + const double CB_length = (B - C).length(); + const double AB_length = (B - A).length(); + Geom::Point C_reflect_scaled = B + (B - C) / CB_length * AB_length; + double tolerance_C_reflect_scaled = tolerance_B + + (tolerance_B + tolerance_C) + * (1 + (tolerance_A + tolerance_B) / AB_length) + * (1 + (tolerance_C + tolerance_B) / CB_length); + return Geom::are_near(C_reflect_scaled, A, tolerance_C_reflect_scaled + tolerance_A); +} + +} // namespace + +namespace Inkscape { +namespace UI { + +const double NO_POWER = 0.0; +const double DEFAULT_START_POWER = 1.0/3.0; + +ControlPoint::ColorSet Node::node_colors = { + {0xbfbfbf00, 0x000000ff}, // normal fill, stroke + {0xff000000, 0x000000ff}, // mouseover fill, stroke + {0xff000000, 0x000000ff}, // clicked fill, stroke + // + {0x0000ffff, 0x000000ff}, // normal fill, stroke when selected + {0xff000000, 0x000000ff}, // mouseover fill, stroke when selected + {0xff000000, 0x000000ff} // clicked fill, stroke when selected +}; + +ControlPoint::ColorSet Handle::_handle_colors = { + {0xffffffff, 0x000000ff}, // normal fill, stroke + {0xff000000, 0x000000ff}, // mouseover fill, stroke + {0xff000000, 0x000000ff}, // clicked fill, stroke + // + {0xffffffff, 0x000000ff}, // normal fill, stroke + {0xff000000, 0x000000ff}, // mouseover fill, stroke + {0xff000000, 0x000000ff} // clicked fill, stroke +}; + +std::ostream &operator<<(std::ostream &out, NodeType type) +{ + switch(type) { + case NODE_CUSP: out << 'c'; break; + case NODE_SMOOTH: out << 's'; break; + case NODE_AUTO: out << 'a'; break; + case NODE_SYMMETRIC: out << 'z'; break; + default: out << 'b'; break; + } + return out; +} + +/** Computes an unit vector of the direction from first to second control point */ +static Geom::Point direction(Geom::Point const &first, Geom::Point const &second) { + return Geom::unit_vector(second - first); +} + +Geom::Point Handle::_saved_other_pos(0, 0); + +double Handle::_saved_length = 0.0; + +bool Handle::_drag_out = false; + +Handle::Handle(NodeSharedData const &data, Geom::Point const &initial_pos, Node *parent) + : ControlPoint(data.desktop, initial_pos, SP_ANCHOR_CENTER, + Inkscape::CANVAS_ITEM_CTRL_TYPE_ROTATE, + _handle_colors, data.handle_group) + , _handle_line(new Inkscape::CanvasItemCurve(data.handle_line_group)) + , _parent(parent) + , _degenerate(true) +{ + setVisible(false); +} + +Handle::~Handle() +{ + delete _handle_line; +} + +void Handle::setVisible(bool v) +{ + ControlPoint::setVisible(v); + if (v) { + _handle_line->show(); + } else { + _handle_line->hide(); + } +} + +void Handle::move(Geom::Point const &new_pos) +{ + Handle *other = this->other(); + Node *node_towards = _parent->nodeToward(this); // node in direction of this handle + Node *node_away = _parent->nodeAwayFrom(this); // node in the opposite direction + Handle *towards = node_towards ? node_towards->handleAwayFrom(_parent) : nullptr; + Handle *towards_second = node_towards ? node_towards->handleToward(_parent) : nullptr; + double bspline_weight = 0.0; + + if (Geom::are_near(new_pos, _parent->position())) { + // The handle becomes degenerate. + // Adjust node type as necessary. + if (other->isDegenerate()) { + // If both handles become degenerate, convert to parent cusp node + _parent->setType(NODE_CUSP, false); + } else { + // Only 1 handle becomes degenerate + switch (_parent->type()) { + case NODE_AUTO: + case NODE_SYMMETRIC: + _parent->setType(NODE_SMOOTH, false); + break; + default: + // do nothing for other node types + break; + } + } + // If the segment between the handle and the node in its direction becomes linear, + // and there are smooth nodes at its ends, make their handles collinear with the segment. + if (towards && towards_second->isDegenerate()) { + if (node_towards->type() == NODE_SMOOTH) { + towards->setDirection(*_parent, *node_towards); + } + if (_parent->type() == NODE_SMOOTH) { + other->setDirection(*node_towards, *_parent); + } + } + setPosition(new_pos); + + // move the handle and its opposite the same proportion + if(_pm()._isBSpline()){ + setPosition(_pm()._bsplineHandleReposition(this, false)); + bspline_weight = _pm()._bsplineHandlePosition(this, false); + this->other()->setPosition(_pm()._bsplineHandleReposition(this->other(), bspline_weight)); + } + return; + } + + if (_parent->type() == NODE_SMOOTH && Node::_is_line_segment(_parent, node_away)) { + // restrict movement to the line joining the nodes + Geom::Point direction = _parent->position() - node_away->position(); + Geom::Point delta = new_pos - _parent->position(); + // project the relative position on the direction line + Geom::Coord direction_length = Geom::L2sq(direction); + Geom::Point new_delta; + if (direction_length == 0) { + // joining line has zero length - any direction is okay, prevent division by zero + new_delta = delta; + } else { + new_delta = (Geom::dot(delta, direction) / direction_length) * direction; + } + setRelativePos(new_delta); + + // move the handle and its opposite the same proportion + if(_pm()._isBSpline()){ + setPosition(_pm()._bsplineHandleReposition(this, false)); + bspline_weight = _pm()._bsplineHandlePosition(this, false); + this->other()->setPosition(_pm()._bsplineHandleReposition(this->other(), bspline_weight)); + } + + return; + } + + switch (_parent->type()) { + case NODE_AUTO: + _parent->setType(NODE_SMOOTH, false); + // fall through - auto nodes degrade into smooth nodes + case NODE_SMOOTH: { + // for smooth nodes, we need to rotate the opposite handle + // so that it's collinear with the dragged one, while conserving length. + other->setDirection(new_pos, *_parent); + } break; + case NODE_SYMMETRIC: + // for symmetric nodes, place the other handle on the opposite side + other->setRelativePos(-(new_pos - _parent->position())); + break; + default: break; + } + setPosition(new_pos); + + // move the handle and its opposite the same proportion + if(_pm()._isBSpline()){ + setPosition(_pm()._bsplineHandleReposition(this, false)); + bspline_weight = _pm()._bsplineHandlePosition(this, false); + this->other()->setPosition(_pm()._bsplineHandleReposition(this->other(), bspline_weight)); + } + Inkscape::UI::Tools::sp_update_helperpath(_desktop); +} + +void Handle::setPosition(Geom::Point const &p) +{ + ControlPoint::setPosition(p); + _handle_line->set_coords(_parent->position(), position()); + + // update degeneration info and visibility + if (Geom::are_near(position(), _parent->position())) + _degenerate = true; + else _degenerate = false; + + if (_parent->_handles_shown && _parent->visible() && !_degenerate) { + setVisible(true); + } else { + setVisible(false); + } +} + +void Handle::setLength(double len) +{ + if (isDegenerate()) return; + Geom::Point dir = Geom::unit_vector(relativePos()); + setRelativePos(dir * len); +} + +void Handle::retract() +{ + move(_parent->position()); +} + +void Handle::setDirection(Geom::Point const &from, Geom::Point const &to) +{ + setDirection(to - from); +} + +void Handle::setDirection(Geom::Point const &dir) +{ + Geom::Point unitdir = Geom::unit_vector(dir); + setRelativePos(unitdir * length()); +} + +/** + * See also: Node::node_type_to_localized_string(NodeType type) + */ +char const *Handle::handle_type_to_localized_string(NodeType type) +{ + switch(type) { + case NODE_CUSP: + return _("Corner node handle"); + case NODE_SMOOTH: + return _("Smooth node handle"); + case NODE_SYMMETRIC: + return _("Symmetric node handle"); + case NODE_AUTO: + return _("Auto-smooth node handle"); + default: + return ""; + } +} + +bool Handle::_eventHandler(Inkscape::UI::Tools::ToolBase *event_context, GdkEvent *event) +{ + switch (event->type) + { + case GDK_KEY_PRESS: + + switch (shortcut_key(event->key)) + { + case GDK_KEY_s: + case GDK_KEY_S: + + /* if Shift+S is pressed while hovering over a cusp node handle, + hold the handle in place; otherwise, process normally. + this handle is guaranteed not to be degenerate. */ + + if (held_only_shift(event->key) && _parent->_type == NODE_CUSP) { + + // make opposite handle collinear, + // but preserve length, unless degenerate + if (other()->isDegenerate()) + other()->setRelativePos(-relativePos()); + else + other()->setDirection(-relativePos()); + _parent->setType(NODE_SMOOTH, false); + + // update display + _parent->_pm().update(); + + // update undo history + _parent->_pm()._commit(_("Change node type")); + + return true; + } + break; + + case GDK_KEY_y: + case GDK_KEY_Y: + + /* if Shift+Y is pressed while hovering over a cusp, smooth, or auto node handle, + hold the handle in place; otherwise, process normally. + this handle is guaranteed not to be degenerate. */ + + if (held_only_shift(event->key) && (_parent->_type == NODE_CUSP || + _parent->_type == NODE_SMOOTH || + _parent->_type == NODE_AUTO)) { + + // make opposite handle collinear, and of equal length + other()->setRelativePos(-relativePos()); + _parent->setType(NODE_SYMMETRIC, false); + + // update display + _parent->_pm().update(); + + // update undo history + _parent->_pm()._commit(_("Change node type")); + + return true; + } + break; + } + break; + + case GDK_2BUTTON_PRESS: + + // double-click event to set the handles of a node + // to the position specified by DEFAULT_START_POWER + handle_2button_press(); + break; + } + + return ControlPoint::_eventHandler(event_context, event); +} + +// this function moves the handle and its opposite to the position specified by DEFAULT_START_POWER +void Handle::handle_2button_press(){ + if(_pm()._isBSpline()){ + setPosition(_pm()._bsplineHandleReposition(this, DEFAULT_START_POWER)); + this->other()->setPosition(_pm()._bsplineHandleReposition(this->other(), DEFAULT_START_POWER)); + _pm().update(); + } +} + +bool Handle::grabbed(GdkEventMotion *) +{ + _saved_other_pos = other()->position(); + _saved_length = _drag_out ? 0 : length(); + _pm()._handleGrabbed(); + return false; +} + +void Handle::dragged(Geom::Point &new_pos, GdkEventMotion *event) +{ + Geom::Point parent_pos = _parent->position(); + Geom::Point origin = _last_drag_origin(); + SnapManager &sm = _desktop->namedview->snap_manager; + bool snap = held_shift(*event) ? false : sm.someSnapperMightSnap(); + std::optional<Inkscape::Snapper::SnapConstraint> ctrl_constraint; + + // with Alt, preserve length + if (held_alt(*event)) { + new_pos = parent_pos + Geom::unit_vector(new_pos - parent_pos) * _saved_length; + snap = false; + } + // with Ctrl, constrain to M_PI/rotationsnapsperpi increments from vertical + // and the original position. + if (held_control(*event)) { + Inkscape::Preferences *prefs = Inkscape::Preferences::get(); + int snaps = 2 * prefs->getIntLimited("/options/rotationsnapsperpi/value", 12, 1, 1000); + + // note: if snapping to the original position is only desired in the original + // direction of the handle, change to Ray instead of Line + Geom::Line original_line(parent_pos, origin); + Geom::Line perp_line(parent_pos, parent_pos + Geom::rot90(origin - parent_pos)); + Geom::Point snap_pos = parent_pos + Geom::constrain_angle( + Geom::Point(0,0), new_pos - parent_pos, snaps, Geom::Point(1,0)); + Geom::Point orig_pos = original_line.pointAt(original_line.nearestTime(new_pos)); + Geom::Point perp_pos = perp_line.pointAt(perp_line.nearestTime(new_pos)); + + Geom::Point result = snap_pos; + ctrl_constraint = Inkscape::Snapper::SnapConstraint(parent_pos, parent_pos - snap_pos); + if (Geom::distance(orig_pos, new_pos) < Geom::distance(result, new_pos)) { + result = orig_pos; + ctrl_constraint = Inkscape::Snapper::SnapConstraint(parent_pos, parent_pos - orig_pos); + } + if (Geom::distance(perp_pos, new_pos) < Geom::distance(result, new_pos)) { + result = perp_pos; + ctrl_constraint = Inkscape::Snapper::SnapConstraint(parent_pos, parent_pos - perp_pos); + } + new_pos = result; + // move the handle and its opposite in X fixed positions depending on parameter "steps with control" + // by default in live BSpline + if(_pm()._isBSpline()){ + setPosition(new_pos); + int steps = _pm()._bsplineGetSteps(); + new_pos=_pm()._bsplineHandleReposition(this,ceilf(_pm()._bsplineHandlePosition(this, false)*steps)/steps); + } + } + + std::vector<Inkscape::SnapCandidatePoint> unselected; + // if the snap adjustment is activated and it is not BSpline + if (snap && !_pm()._isBSpline()) { + ControlPointSelection::Set &nodes = _parent->_selection.allPoints(); + for (auto node : nodes) { + Node *n = static_cast<Node*>(node); + unselected.push_back(n->snapCandidatePoint()); + } + sm.setupIgnoreSelection(_desktop, true, &unselected); + + Node *node_away = _parent->nodeAwayFrom(this); + if (_parent->type() == NODE_SMOOTH && Node::_is_line_segment(_parent, node_away)) { + Inkscape::Snapper::SnapConstraint cl(_parent->position(), + _parent->position() - node_away->position()); + Inkscape::SnappedPoint p; + p = sm.constrainedSnap(Inkscape::SnapCandidatePoint(new_pos, SNAPSOURCE_NODE_HANDLE), cl); + new_pos = p.getPoint(); + } else if (ctrl_constraint) { + // NOTE: this is subtly wrong. + // We should get all possible constraints and snap along them using + // multipleConstrainedSnaps, instead of first snapping to angle and then to objects + Inkscape::SnappedPoint p; + p = sm.constrainedSnap(Inkscape::SnapCandidatePoint(new_pos, SNAPSOURCE_NODE_HANDLE), *ctrl_constraint); + new_pos = p.getPoint(); + } else { + sm.freeSnapReturnByRef(new_pos, SNAPSOURCE_NODE_HANDLE); + } + sm.unSetup(); + } + + + // with Shift, if the node is cusp, rotate the other handle as well + if (_parent->type() == NODE_CUSP && !_drag_out) { + if (held_shift(*event)) { + Geom::Point other_relpos = _saved_other_pos - parent_pos; + other_relpos *= Geom::Rotate(Geom::angle_between(origin - parent_pos, new_pos - parent_pos)); + other()->setRelativePos(other_relpos); + } else { + // restore the position + other()->setPosition(_saved_other_pos); + } + } + // if it is BSpline, but SHIFT or CONTROL are not pressed, fix it in the original position + if(_pm()._isBSpline() && !held_shift(*event) && !held_control(*event)){ + new_pos=_last_drag_origin(); + } + _pm().update(); +} + +void Handle::ungrabbed(GdkEventButton *event) +{ + // hide the handle if it's less than dragtolerance away from the node + // however, never do this for cancelled drag / broken grab + // TODO is this actually a good idea? + if (event) { + Inkscape::Preferences *prefs = Inkscape::Preferences::get(); + int drag_tolerance = prefs->getIntLimited("/options/dragtolerance/value", 0, 0, 100); + + Geom::Point dist = _desktop->d2w(_parent->position()) - _desktop->d2w(position()); + if (dist.length() <= drag_tolerance) { + move(_parent->position()); + } + } + + // HACK: If the handle was dragged out, call parent's ungrabbed handler, + // so that transform handles reappear + if (_drag_out) { + _parent->ungrabbed(event); + } + _drag_out = false; + + _pm()._handleUngrabbed(); +} + +bool Handle::clicked(GdkEventButton *event) +{ + _pm()._handleClicked(this, event); + return true; +} + +Handle const *Handle::other() const +{ + return const_cast<Handle *>(this)->other(); +} + +Handle *Handle::other() +{ + if (this == &_parent->_front) { + return &_parent->_back; + } else { + return &_parent->_front; + } +} + +static double snap_increment_degrees() { + Inkscape::Preferences *prefs = Inkscape::Preferences::get(); + int snaps = prefs->getIntLimited("/options/rotationsnapsperpi/value", 12, 1, 1000); + return 180.0 / snaps; +} + +Glib::ustring Handle::_getTip(unsigned state) const +{ + /* a trick to mark as BSpline if the node has no strength; + we are going to use it later to show the appropriate messages. + we cannot do it in any different way because the function is constant. */ + Handle *h = const_cast<Handle *>(this); + bool isBSpline = _pm()._isBSpline(); + bool can_shift_rotate = _parent->type() == NODE_CUSP && !other()->isDegenerate(); + Glib::ustring s = C_("Path handle tip", + "node control handle"); // not expected + + if (state_held_alt(state) && !isBSpline) { + if (state_held_control(state)) { + if (state_held_shift(state) && can_shift_rotate) { + s = format_tip(C_("Path handle tip", + "<b>Shift+Ctrl+Alt</b>: " + "preserve length and snap rotation angle to %g° increments, " + "and rotate both handles"), + snap_increment_degrees()); + } + else { + s = format_tip(C_("Path handle tip", + "<b>Ctrl+Alt</b>: " + "preserve length and snap rotation angle to %g° increments"), + snap_increment_degrees()); + } + } + else { + if (state_held_shift(state) && can_shift_rotate) { + s = C_("Path handle tip", + "<b>Shift+Alt</b>: preserve handle length and rotate both handles"); + } + else { + s = C_("Path handle tip", + "<b>Alt</b>: preserve handle length while dragging"); + } + } + } + else { + if (state_held_control(state)) { + if (state_held_shift(state) && can_shift_rotate && !isBSpline) { + s = format_tip(C_("Path handle tip", + "<b>Shift+Ctrl</b>: " + "snap rotation angle to %g° increments, and rotate both handles"), + snap_increment_degrees()); + } + else if (isBSpline) { + s = C_("Path handle tip", + "<b>Ctrl</b>: " + "Snap handle to steps defined in BSpline Live Path Effect"); + } + else { + s = format_tip(C_("Path handle tip", + "<b>Ctrl</b>: " + "snap rotation angle to %g° increments, click to retract"), + snap_increment_degrees()); + } + } + else if (state_held_shift(state) && can_shift_rotate && !isBSpline) { + s = C_("Path handle tip", + "<b>Shift</b>: rotate both handles by the same angle"); + } + else if (state_held_shift(state) && isBSpline) { + s = C_("Path handle tip", + "<b>Shift</b>: move handle"); + } + else { + char const *handletype = handle_type_to_localized_string(_parent->_type); + char const *more; + + if (can_shift_rotate && !isBSpline) { + more = C_("Path handle tip", + "Shift, Ctrl, Alt"); + } + else if (isBSpline) { + more = C_("Path handle tip", + "Ctrl"); + } + else { + more = C_("Path handle tip", + "Ctrl, Alt"); + } + + if (_parent->type() == NODE_CUSP) { + s = format_tip(C_("Path handle tip", + "<b>%s</b>: " + "drag to shape the path" ", " + "hover to lock" ", " + "Shift+S to make smooth" ", " + "Shift+Y to make symmetric" ". " + "(more: %s)"), + handletype, more); + } + else if (_parent->type() == NODE_SMOOTH) { + s = format_tip(C_("Path handle tip", + "<b>%s</b>: " + "drag to shape the path" ", " + "hover to lock" ", " + "Shift+Y to make symmetric" ". " + "(more: %s)"), + handletype, more); + } + else if (_parent->type() == NODE_AUTO) { + s = format_tip(C_("Path handle tip", + "<b>%s</b>: " + "drag to make smooth, " + "hover to lock" ", " + "Shift+Y to make symmetric" ". " + "(more: %s)"), + handletype, more); + } + else if (_parent->type() == NODE_SYMMETRIC) { + s = format_tip(C_("Path handle tip", + "<b>%s</b>: " + "drag to shape the path" ". " + "(more: %s)"), + handletype, more); + } + else if (isBSpline) { + double power = _pm()._bsplineHandlePosition(h); + s = format_tip(C_("Path handle tip", + "<b>BSpline node handle</b> (%.3g power): " + "Shift-drag to move, " + "double-click to reset. " + "(more: %s)"), + power, more); + } + else { + s = C_("Path handle tip", + "<b>unknown node handle</b>"); // not expected + } + } + } + + return (s); +} + +Glib::ustring Handle::_getDragTip(GdkEventMotion */*event*/) const +{ + Geom::Point dist = position() - _last_drag_origin(); + // report angle in mathematical convention + double angle = Geom::angle_between(Geom::Point(-1,0), position() - _parent->position()); + angle += M_PI; // angle is (-M_PI...M_PI] - offset by +pi and scale to 0...360 + angle *= 360.0 / (2 * M_PI); + + Inkscape::Util::Quantity x_q = Inkscape::Util::Quantity(dist[Geom::X], "px"); + Inkscape::Util::Quantity y_q = Inkscape::Util::Quantity(dist[Geom::Y], "px"); + Inkscape::Util::Quantity len_q = Inkscape::Util::Quantity(length(), "px"); + Glib::ustring x = x_q.string(_desktop->namedview->display_units); + Glib::ustring y = y_q.string(_desktop->namedview->display_units); + Glib::ustring len = len_q.string(_desktop->namedview->display_units); + Glib::ustring ret = format_tip(C_("Path handle tip", + "Move handle by %s, %s; angle %.2f°, length %s"), x.c_str(), y.c_str(), angle, len.c_str()); + return ret; +} + +Node::Node(NodeSharedData const &data, Geom::Point const &initial_pos) : + SelectableControlPoint(data.desktop, initial_pos, SP_ANCHOR_CENTER, + Inkscape::CANVAS_ITEM_CTRL_TYPE_NODE_CUSP, + *data.selection, + node_colors, data.node_group), + _front(data, initial_pos, this), + _back(data, initial_pos, this), + _type(NODE_CUSP), + _handles_shown(false) +{ + _canvas_item_ctrl->set_name("CanvasItemCtrl:Node"); + // NOTE we do not set type here, because the handles are still degenerate +} + +Node const *Node::_next() const +{ + return const_cast<Node*>(this)->_next(); +} + +// NOTE: not using iterators won't make this much quicker because iterators can be 100% inlined. +Node *Node::_next() +{ + NodeList::iterator n = NodeList::get_iterator(this).next(); + if (n) { + return n.ptr(); + } else { + return nullptr; + } +} + +Node const *Node::_prev() const +{ + return const_cast<Node *>(this)->_prev(); +} + +Node *Node::_prev() +{ + NodeList::iterator p = NodeList::get_iterator(this).prev(); + if (p) { + return p.ptr(); + } else { + return nullptr; + } +} + +void Node::move(Geom::Point const &new_pos) +{ + // move handles when the node moves. + Geom::Point old_pos = position(); + Geom::Point delta = new_pos - position(); + + // save the previous nodes strength to apply it again once the node is moved + double nodeWeight = NO_POWER; + double nextNodeWeight = NO_POWER; + double prevNodeWeight = NO_POWER; + Node *n = this; + Node * nextNode = n->nodeToward(n->front()); + Node * prevNode = n->nodeToward(n->back()); + nodeWeight = fmax(_pm()._bsplineHandlePosition(n->front(), false),_pm()._bsplineHandlePosition(n->back(), false)); + if(prevNode){ + prevNodeWeight = _pm()._bsplineHandlePosition(prevNode->front()); + } + if(nextNode){ + nextNodeWeight = _pm()._bsplineHandlePosition(nextNode->back()); + } + + // Save original position for post-processing + _unfixed_pos = std::optional<Geom::Point>(position()); + + setPosition(new_pos); + _front.setPosition(_front.position() + delta); + _back.setPosition(_back.position() + delta); + + // move the affected handles. First the node ones, later the adjoining ones. + if(_pm()._isBSpline()){ + _front.setPosition(_pm()._bsplineHandleReposition(this->front(),nodeWeight)); + _back.setPosition(_pm()._bsplineHandleReposition(this->back(),nodeWeight)); + if(prevNode){ + prevNode->front()->setPosition(_pm()._bsplineHandleReposition(prevNode->front(), prevNodeWeight)); + } + if(nextNode){ + nextNode->back()->setPosition(_pm()._bsplineHandleReposition(nextNode->back(), nextNodeWeight)); + } + } +} + +void Node::transform(Geom::Affine const &m) +{ + // save the previous nodes strength to apply it again once the node is moved + double nodeWeight = NO_POWER; + double nextNodeWeight = NO_POWER; + double prevNodeWeight = NO_POWER; + Node *n = this; + Node * nextNode = n->nodeToward(n->front()); + Node * prevNode = n->nodeToward(n->back()); + nodeWeight = _pm()._bsplineHandlePosition(n->front()); + if(prevNode){ + prevNodeWeight = _pm()._bsplineHandlePosition(prevNode->front()); + } + if(nextNode){ + nextNodeWeight = _pm()._bsplineHandlePosition(nextNode->back()); + } + + // Save original position for post-processing + _unfixed_pos = std::optional<Geom::Point>(position()); + + setPosition(position() * m); + _front.setPosition(_front.position() * m); + _back.setPosition(_back.position() * m); + + // move the involved handles. First the node ones, later the adjoining ones. + if(_pm()._isBSpline()){ + _front.setPosition(_pm()._bsplineHandleReposition(this->front(), nodeWeight)); + _back.setPosition(_pm()._bsplineHandleReposition(this->back(), nodeWeight)); + if(prevNode){ + prevNode->front()->setPosition(_pm()._bsplineHandleReposition(prevNode->front(), prevNodeWeight)); + } + if(nextNode){ + nextNode->back()->setPosition(_pm()._bsplineHandleReposition(nextNode->back(), nextNodeWeight)); + } + } +} + +Geom::Rect Node::bounds() const +{ + Geom::Rect b(position(), position()); + b.expandTo(_front.position()); + b.expandTo(_back.position()); + return b; +} + +/** + * Affine transforms keep handle invariants for smooth and symmetric nodes, + * but smooth nodes at ends of linear segments and auto nodes need special treatment + * + * Call this function once you have finished called ::move or ::transform on ALL nodes + * that are being transformed in that one operation to avoid problematic bugs. + */ +void Node::fixNeighbors() +{ + if (!_unfixed_pos) + return; + + Geom::Point const new_pos = position(); + + // This method restores handle invariants for neighboring nodes, + // and invariants that are based on positions of those nodes for this one. + + // Fix auto handles + if (_type == NODE_AUTO) _updateAutoHandles(); + if (*_unfixed_pos != new_pos) { + if (_next() && _next()->_type == NODE_AUTO) _next()->_updateAutoHandles(); + if (_prev() && _prev()->_type == NODE_AUTO) _prev()->_updateAutoHandles(); + } + + /* Fix smooth handles at the ends of linear segments. + Rotate the appropriate handle to be collinear with the segment. + If there is a smooth node at the other end of the segment, rotate it too. */ + Handle *handle, *other_handle; + Node *other; + if (_is_line_segment(this, _next())) { + handle = &_back; + other = _next(); + other_handle = &_next()->_front; + } else if (_is_line_segment(_prev(), this)) { + handle = &_front; + other = _prev(); + other_handle = &_prev()->_back; + } else return; + + if (_type == NODE_SMOOTH && !handle->isDegenerate()) { + handle->setDirection(other->position(), new_pos); + } + // also update the handle on the other end of the segment + if (other->_type == NODE_SMOOTH && !other_handle->isDegenerate()) { + other_handle->setDirection(new_pos, other->position()); + } + + _unfixed_pos.reset(); +} + +void Node::_updateAutoHandles() +{ + // Recompute the position of automatic handles. For endnodes, retract both handles. + // (It's only possible to create an end auto node through the XML editor.) + if (isEndNode()) { + _front.retract(); + _back.retract(); + return; + } + + // auto nodes automatically adjust their handles to give + // an appearance of smoothness, no matter what their surroundings are. + Geom::Point vec_next = _next()->position() - position(); + Geom::Point vec_prev = _prev()->position() - position(); + double len_next = vec_next.length(), len_prev = vec_prev.length(); + if (len_next > 0 && len_prev > 0) { + // "dir" is an unit vector perpendicular to the bisector of the angle created + // by the previous node, this auto node and the next node. + Geom::Point dir = Geom::unit_vector((len_prev / len_next) * vec_next - vec_prev); + // Handle lengths are equal to 1/3 of the distance from the adjacent node. + _back.setRelativePos(-dir * (len_prev / 3)); + _front.setRelativePos(dir * (len_next / 3)); + } else { + // If any of the adjacent nodes coincides, retract both handles. + _front.retract(); + _back.retract(); + } +} + +void Node::showHandles(bool v) +{ + _handles_shown = v; + if (!_front.isDegenerate()) { + _front.setVisible(v); + } + if (!_back.isDegenerate()) { + _back.setVisible(v); + } + +} + +void Node::updateHandles() +{ + _handleControlStyling(); + + _front._handleControlStyling(); + _back._handleControlStyling(); +} + + +void Node::setType(NodeType type, bool update_handles) +{ + if (type == NODE_PICK_BEST) { + pickBestType(); + updateState(); // The size of the control might have changed + return; + } + + // if update_handles is true, adjust handle positions to match the node type + // handle degenerate handles appropriately + if (update_handles) { + switch (type) { + case NODE_CUSP: + // nothing to do + break; + case NODE_AUTO: + // auto handles make no sense for endnodes + if (isEndNode()) return; + _updateAutoHandles(); + break; + case NODE_SMOOTH: { + // ignore attempts to make smooth endnodes. + if (isEndNode()) return; + // rotate handles to be collinear + // for degenerate nodes set positions like auto handles + bool prev_line = _is_line_segment(_prev(), this); + bool next_line = _is_line_segment(this, _next()); + if (_type == NODE_SMOOTH) { + // For a node that is already smooth and has a degenerate handle, + // drag out the second handle without changing the direction of the first one. + if (_front.isDegenerate()) { + double dist = Geom::distance(_next()->position(), position()); + _front.setRelativePos(Geom::unit_vector(-_back.relativePos()) * dist / 3); + } + if (_back.isDegenerate()) { + double dist = Geom::distance(_prev()->position(), position()); + _back.setRelativePos(Geom::unit_vector(-_front.relativePos()) * dist / 3); + } + } else if (isDegenerate()) { + _updateAutoHandles(); + } else if (_front.isDegenerate()) { + // if the front handle is degenerate and next path segment is a line, make back collinear; + // otherwise, pull out the other handle to 1/3 of distance to prev. + if (next_line) { + _back.setDirection(*_next(), *this); + } else if (_prev()) { + Geom::Point dir = direction(_back, *this); + _front.setRelativePos(Geom::distance(_prev()->position(), position()) / 3 * dir); + } + } else if (_back.isDegenerate()) { + if (prev_line) { + _front.setDirection(*_prev(), *this); + } else if (_next()) { + Geom::Point dir = direction(_front, *this); + _back.setRelativePos(Geom::distance(_next()->position(), position()) / 3 * dir); + } + } else { + /* both handles are extended. make collinear while keeping length. + first make back collinear with the vector front ---> back, + then make front collinear with back ---> node. + (not back ---> front, because back's position was changed in the first call) */ + _back.setDirection(_front, _back); + _front.setDirection(_back, *this); + } + } break; + case NODE_SYMMETRIC: + if (isEndNode()) return; // symmetric handles make no sense for endnodes + if (isDegenerate()) { + // similar to auto handles but set the same length for both + Geom::Point vec_next = _next()->position() - position(); + Geom::Point vec_prev = _prev()->position() - position(); + double len_next = vec_next.length(), len_prev = vec_prev.length(); + double len = (len_next + len_prev) / 6; // take 1/3 of average + if (len == 0) return; + + Geom::Point dir = Geom::unit_vector((len_prev / len_next) * vec_next - vec_prev); + _back.setRelativePos(-dir * len); + _front.setRelativePos(dir * len); + } else { + // Both handles are extended. Compute average length, use direction from + // back handle to front handle. This also works correctly for degenerates + double len = (_front.length() + _back.length()) / 2; + Geom::Point dir = direction(_back, _front); + _front.setRelativePos(dir * len); + _back.setRelativePos(-dir * len); + } + break; + default: break; + } + // in node type changes, for BSpline traces, we can either maintain them + // with NO_POWER power in border mode, or give them the default power in curve mode. + if(_pm()._isBSpline()){ + double weight = NO_POWER; + if(_pm()._bsplineHandlePosition(this->front()) != NO_POWER ){ + weight = DEFAULT_START_POWER; + } + _front.setPosition(_pm()._bsplineHandleReposition(this->front(), weight)); + _back.setPosition(_pm()._bsplineHandleReposition(this->back(), weight)); + } + } + _type = type; + _setControlType(nodeTypeToCtrlType(_type)); + updateState(); +} + +void Node::pickBestType() +{ + _type = NODE_CUSP; + bool front_degen = _front.isDegenerate(); + bool back_degen = _back.isDegenerate(); + bool both_degen = front_degen && back_degen; + bool neither_degen = !front_degen && !back_degen; + do { + // if both handles are degenerate, do nothing + if (both_degen) break; + // if neither are degenerate, check their respective positions + if (neither_degen) { + // for now do not automatically make nodes symmetric, it can be annoying + /*if (Geom::are_near(front_delta, -back_delta)) { + _type = NODE_SYMMETRIC; + break; + }*/ + if (are_collinear_within_serializing_error(_front.position(), position(), _back.position())) { + _type = NODE_SMOOTH; + break; + } + } + // check whether the handle aligns with the previous line segment. + // we know that if front is degenerate, back isn't, because + // both_degen was false + if (front_degen && _next() && _next()->_back.isDegenerate()) { + if (are_collinear_within_serializing_error(_next()->position(), position(), _back.position())) { + _type = NODE_SMOOTH; + break; + } + } else if (back_degen && _prev() && _prev()->_front.isDegenerate()) { + if (are_collinear_within_serializing_error(_prev()->position(), position(), _front.position())) { + _type = NODE_SMOOTH; + break; + } + } + } while (false); + _setControlType(nodeTypeToCtrlType(_type)); + updateState(); +} + +bool Node::isEndNode() const +{ + return !_prev() || !_next(); +} + +void Node::sink() +{ + _canvas_item_ctrl->set_z_position(0); +} + +NodeType Node::parse_nodetype(char x) +{ + switch (x) { + case 'a': return NODE_AUTO; + case 'c': return NODE_CUSP; + case 's': return NODE_SMOOTH; + case 'z': return NODE_SYMMETRIC; + default: return NODE_PICK_BEST; + } +} + +bool Node::_eventHandler(Inkscape::UI::Tools::ToolBase *event_context, GdkEvent *event) +{ + int dir = 0; + + switch (event->type) + { + case GDK_SCROLL: + if (event->scroll.direction == GDK_SCROLL_UP) { + dir = 1; + } else if (event->scroll.direction == GDK_SCROLL_DOWN) { + dir = -1; + } else if (event->scroll.direction == GDK_SCROLL_SMOOTH) { + dir = event->scroll.delta_y > 0 ? -1 : 1; + } else { + break; + } + if (held_control(event->scroll)) { + _linearGrow(dir); + } else { + _selection.spatialGrow(this, dir); + } + return true; + case GDK_KEY_PRESS: + switch (shortcut_key(event->key)) + { + case GDK_KEY_Page_Up: + dir = 1; + break; + case GDK_KEY_Page_Down: + dir = -1; + break; + default: goto bail_out; + } + + if (held_control(event->key)) { + _linearGrow(dir); + } else { + _selection.spatialGrow(this, dir); + } + return true; + + default: + break; + } + + bail_out: + return ControlPoint::_eventHandler(event_context, event); +} + +void Node::_linearGrow(int dir) +{ + // Interestingly, we do not need any help from PathManipulator when doing linear grow. + // First handle the trivial case of growing over an unselected node. + if (!selected() && dir > 0) { + _selection.insert(this); + return; + } + + NodeList::iterator this_iter = NodeList::get_iterator(this); + NodeList::iterator fwd = this_iter, rev = this_iter; + double distance_back = 0, distance_front = 0; + + // Linear grow is simple. We find the first unselected nodes in each direction + // and compare the linear distances to them. + if (dir > 0) { + if (!selected()) { + _selection.insert(this); + return; + } + + // find first unselected nodes on both sides + while (fwd && fwd->selected()) { + NodeList::iterator n = fwd.next(); + distance_front += Geom::bezier_length(*fwd, fwd->_front, n->_back, *n); + fwd = n; + if (fwd == this_iter) + // there is no unselected node in this cyclic subpath + return; + } + // do the same for the second direction. Do not check for equality with + // this node, because there is at least one unselected node in the subpath, + // so we are guaranteed to stop. + while (rev && rev->selected()) { + NodeList::iterator p = rev.prev(); + distance_back += Geom::bezier_length(*rev, rev->_back, p->_front, *p); + rev = p; + } + + NodeList::iterator t; // node to select + if (fwd && rev) { + if (distance_front <= distance_back) t = fwd; + else t = rev; + } else { + if (fwd) t = fwd; + if (rev) t = rev; + } + if (t) _selection.insert(t.ptr()); + + // Linear shrink is more complicated. We need to find the farthest selected node. + // This means we have to check the entire subpath. We go in the direction in which + // the distance we traveled is lower. We do this until we run out of nodes (ends of path) + // or the two iterators meet. On the way, we store the last selected node and its distance + // in each direction (if any). At the end, we choose the one that is farther and deselect it. + } else { + // both iterators that store last selected nodes are initially empty + NodeList::iterator last_fwd, last_rev; + double last_distance_back = 0, last_distance_front = 0; + + while (rev || fwd) { + if (fwd && (!rev || distance_front <= distance_back)) { + if (fwd->selected()) { + last_fwd = fwd; + last_distance_front = distance_front; + } + NodeList::iterator n = fwd.next(); + if (n) distance_front += Geom::bezier_length(*fwd, fwd->_front, n->_back, *n); + fwd = n; + } else if (rev && (!fwd || distance_front > distance_back)) { + if (rev->selected()) { + last_rev = rev; + last_distance_back = distance_back; + } + NodeList::iterator p = rev.prev(); + if (p) distance_back += Geom::bezier_length(*rev, rev->_back, p->_front, *p); + rev = p; + } + // Check whether we walked the entire cyclic subpath. + // This is initially true because both iterators start from this node, + // so this check cannot go in the while condition. + // When this happens, we need to check the last node, pointed to by the iterators. + if (fwd && fwd == rev) { + if (!fwd->selected()) break; + NodeList::iterator fwdp = fwd.prev(), revn = rev.next(); + double df = distance_front + Geom::bezier_length(*fwdp, fwdp->_front, fwd->_back, *fwd); + double db = distance_back + Geom::bezier_length(*revn, revn->_back, rev->_front, *rev); + if (df > db) { + last_fwd = fwd; + last_distance_front = df; + } else { + last_rev = rev; + last_distance_back = db; + } + break; + } + } + + NodeList::iterator t; + if (last_fwd && last_rev) { + if (last_distance_front >= last_distance_back) t = last_fwd; + else t = last_rev; + } else { + if (last_fwd) t = last_fwd; + if (last_rev) t = last_rev; + } + if (t) _selection.erase(t.ptr()); + } +} + +void Node::_setState(State state) +{ + // change node size to match type and selection state + _canvas_item_ctrl->set_size_extra(selected() ? 2 : 0); + switch (state) { + // These were used to set "active" and "prelight" flags but the flags weren't being used. + case STATE_NORMAL: + case STATE_MOUSEOVER: + break; + case STATE_CLICKED: + // show the handles when selecting the nodes + if(_pm()._isBSpline()){ + this->front()->setPosition(_pm()._bsplineHandleReposition(this->front())); + this->back()->setPosition(_pm()._bsplineHandleReposition(this->back())); + } + break; + } + SelectableControlPoint::_setState(state); +} + +bool Node::grabbed(GdkEventMotion *event) +{ + if (SelectableControlPoint::grabbed(event)) { + return true; + } + + // Dragging out handles with Shift + drag on a node. + if (!held_shift(*event)) { + return false; + } + + Geom::Point evp = event_point(*event); + Geom::Point rel_evp = evp - _last_click_event_point(); + + // This should work even if dragtolerance is zero and evp coincides with node position. + double angle_next = HUGE_VAL; + double angle_prev = HUGE_VAL; + bool has_degenerate = false; + // determine which handle to drag out based on degeneration and the direction of drag + if (_front.isDegenerate() && _next()) { + Geom::Point next_relpos = _desktop->d2w(_next()->position()) + - _desktop->d2w(position()); + angle_next = fabs(Geom::angle_between(rel_evp, next_relpos)); + has_degenerate = true; + } + if (_back.isDegenerate() && _prev()) { + Geom::Point prev_relpos = _desktop->d2w(_prev()->position()) + - _desktop->d2w(position()); + angle_prev = fabs(Geom::angle_between(rel_evp, prev_relpos)); + has_degenerate = true; + } + if (!has_degenerate) { + return false; + } + + Handle *h = angle_next < angle_prev ? &_front : &_back; + + h->setPosition(_desktop->w2d(evp)); + h->setVisible(true); + h->transferGrab(this, event); + Handle::_drag_out = true; + return true; +} + +void Node::dragged(Geom::Point &new_pos, GdkEventMotion *event) +{ + // For a note on how snapping is implemented in Inkscape, see snap.h. + SnapManager &sm = _desktop->namedview->snap_manager; + // even if we won't really snap, we might still call the one of the + // constrainedSnap() methods to enforce the constraints, so we need + // to setup the snapmanager anyway; this is also required for someSnapperMightSnap() + sm.setup(_desktop); + + // do not snap when Shift is pressed + bool snap = !held_shift(*event) && sm.someSnapperMightSnap(); + + Inkscape::SnappedPoint sp; + std::vector<Inkscape::SnapCandidatePoint> unselected; + if (snap) { + /* setup + * TODO We are doing this every time a snap happens. It should once be done only once + * per drag - maybe in the grabbed handler? + * TODO Unselected nodes vector must be valid during the snap run, because it is not + * copied. Fix this in snap.h and snap.cpp, then the above. + * TODO Snapping to unselected segments of selected paths doesn't work yet. */ + + // Build the list of unselected nodes. + typedef ControlPointSelection::Set Set; + Set &nodes = _selection.allPoints(); + for (auto node : nodes) { + if (!node->selected()) { + Node *n = static_cast<Node*>(node); + Inkscape::SnapCandidatePoint p(n->position(), n->_snapSourceType(), n->_snapTargetType()); + unselected.push_back(p); + } + } + sm.unSetup(); + sm.setupIgnoreSelection(_desktop, true, &unselected); + } + + // Snap candidate point for free snapping; this will consider snapping tangentially + // and perpendicularly and therefore the origin or direction vector must be set + Inkscape::SnapCandidatePoint scp_free(new_pos, _snapSourceType()); + + std::optional<Geom::Point> front_point, back_point; + Geom::Point origin = _last_drag_origin(); + Geom::Point dummy_cp; + if (_front.isDegenerate()) { // If there is no handle for the path segment towards the next node, then this segment is straight + if (_is_line_segment(this, _next())) { + front_point = _next()->position() - origin; + if (_next()->selected()) { + dummy_cp = _next()->position() - position(); + scp_free.addVector(dummy_cp); + } else { + dummy_cp = _next()->position(); + scp_free.addOrigin(dummy_cp); + } + } + } else { // .. this path segment is curved + front_point = _front.relativePos(); + scp_free.addVector(*front_point); + } + if (_back.isDegenerate()) { // If there is no handle for the path segment towards the previous node, then this segment is straight + if (_is_line_segment(_prev(), this)) { + back_point = _prev()->position() - origin; + if (_prev()->selected()) { + dummy_cp = _prev()->position() - position(); + scp_free.addVector(dummy_cp); + } else { + dummy_cp = _prev()->position(); + scp_free.addOrigin(dummy_cp); + } + } + } else { // .. this path segment is curved + back_point = _back.relativePos(); + scp_free.addVector(*back_point); + } + + if (held_control(*event)) { + // We're about to consider a constrained snap, which is already limited to 1D + // Therefore tangential or perpendicular snapping will not be considered, and therefore + // all calls above to scp_free.addVector() and scp_free.addOrigin() can be neglected + std::vector<Inkscape::Snapper::SnapConstraint> constraints; + if (held_alt(*event)) { // with Ctrl+Alt, constrain to handle lines + Inkscape::Preferences *prefs = Inkscape::Preferences::get(); + int snaps = prefs->getIntLimited("/options/rotationsnapsperpi/value", 12, 1, 1000); + double min_angle = M_PI / snaps; + + // If the node is cusp and both handles are retracted (degenerate; straight line segment at both sides of the node), then snap to those line segments + if (isDegenerate()) { // Cusp node with both handles retracted + if (front_point) { + constraints.emplace_back(origin, *front_point); + } + if (back_point) { + constraints.emplace_back(origin, *back_point); + } + } + + // For smooth nodes, we will also snap to normals of handle lines. For cusp nodes this would be unintuitive and confusing + // Only snap to the normals when they are further than snap increment away from the second handle constraint + if (_type != NODE_CUSP) { + std::optional<Geom::Point> fperp_point = Geom::rot90(*front_point); + if (fperp_point && (!back_point || + (fabs(Geom::angle_between(*fperp_point, *back_point)) > min_angle && + fabs(Geom::angle_between(*fperp_point, *back_point)) < M_PI - min_angle))) + { + constraints.emplace_back(origin, *fperp_point); + } + + std::optional<Geom::Point> bperp_point = Geom::rot90(*back_point); + if (bperp_point && (!front_point || + (fabs(Geom::angle_between(*bperp_point, *front_point)) > min_angle && + fabs(Geom::angle_between(*bperp_point, *front_point)) < M_PI - min_angle))) + { + constraints.emplace_back(origin, *bperp_point); + } + } + + sp = sm.multipleConstrainedSnaps(Inkscape::SnapCandidatePoint(new_pos, _snapSourceType()), constraints, held_shift(*event)); + } else { + // with Ctrl, constrain to axes + constraints.emplace_back(origin, Geom::Point(1, 0)); + constraints.emplace_back(origin, Geom::Point(0, 1)); + sp = sm.multipleConstrainedSnaps(Inkscape::SnapCandidatePoint(new_pos, _snapSourceType()), constraints, held_shift(*event)); + } + new_pos = sp.getPoint(); + } else if (snap) { + Inkscape::SnappedPoint sp = sm.freeSnap(scp_free); + new_pos = sp.getPoint(); + } + + sm.unSetup(); + + SelectableControlPoint::dragged(new_pos, event); +} + +bool Node::clicked(GdkEventButton *event) +{ + if(_pm()._nodeClicked(this, event)) + return true; + return SelectableControlPoint::clicked(event); +} + +Inkscape::SnapSourceType Node::_snapSourceType() const +{ + if (_type == NODE_SMOOTH || _type == NODE_AUTO) + return SNAPSOURCE_NODE_SMOOTH; + return SNAPSOURCE_NODE_CUSP; +} +Inkscape::SnapTargetType Node::_snapTargetType() const +{ + if (_type == NODE_SMOOTH || _type == NODE_AUTO) + return SNAPTARGET_NODE_SMOOTH; + return SNAPTARGET_NODE_CUSP; +} + +Inkscape::SnapCandidatePoint Node::snapCandidatePoint() +{ + return SnapCandidatePoint(position(), _snapSourceType(), _snapTargetType()); +} + +Handle *Node::handleToward(Node *to) +{ + if (_next() == to) { + return front(); + } + if (_prev() == to) { + return back(); + } + g_error("Node::handleToward(): second node is not adjacent!"); + return nullptr; +} + +Node *Node::nodeToward(Handle *dir) +{ + if (front() == dir) { + return _next(); + } + if (back() == dir) { + return _prev(); + } + g_error("Node::nodeToward(): handle is not a child of this node!"); + return nullptr; +} + +Handle *Node::handleAwayFrom(Node *to) +{ + if (_next() == to) { + return back(); + } + if (_prev() == to) { + return front(); + } + g_error("Node::handleAwayFrom(): second node is not adjacent!"); + return nullptr; +} + +Node *Node::nodeAwayFrom(Handle *h) +{ + if (front() == h) { + return _prev(); + } + if (back() == h) { + return _next(); + } + g_error("Node::nodeAwayFrom(): handle is not a child of this node!"); + return nullptr; +} + +Glib::ustring Node::_getTip(unsigned state) const +{ + bool isBSpline = _pm()._isBSpline(); + Handle *h = const_cast<Handle *>(&_front); + Glib::ustring s = C_("Path node tip", + "node handle"); // not expected + + if (state_held_shift(state)) { + bool can_drag_out = (_next() && _front.isDegenerate()) || + (_prev() && _back.isDegenerate()); + + if (can_drag_out) { + /*if (state_held_control(state)) { + s = format_tip(C_("Path node tip", + "<b>Shift+Ctrl:</b> drag out a handle and snap its angle " + "to %f° increments"), snap_increment_degrees()); + }*/ + s = C_("Path node tip", + "<b>Shift</b>: drag out a handle, click to toggle selection"); + } + else { + s = C_("Path node tip", + "<b>Shift</b>: click to toggle selection"); + } + } + + else if (state_held_control(state)) { + if (state_held_alt(state)) { + s = C_("Path node tip", + "<b>Ctrl+Alt</b>: move along handle lines, click to delete node"); + } + else { + s = C_("Path node tip", + "<b>Ctrl</b>: move along axes, click to change node type"); + } + } + + else if (state_held_alt(state)) { + s = C_("Path node tip", + "<b>Alt</b>: sculpt nodes"); + } + + else { // No modifiers: assemble tip from node type + char const *nodetype = node_type_to_localized_string(_type); + double power = _pm()._bsplineHandlePosition(h); + + if (_selection.transformHandlesEnabled() && selected()) { + if (_selection.size() == 1) { + if (!isBSpline) { + s = format_tip(C_("Path node tip", + "<b>%s</b>: " + "drag to shape the path" ". " + "(more: Shift, Ctrl, Alt)"), + nodetype); + } + else { + s = format_tip(C_("Path node tip", + "<b>BSpline node</b> (%.3g power): " + "drag to shape the path" ". " + "(more: Shift, Ctrl, Alt)"), + power); + } + } + else { + s = format_tip(C_("Path node tip", + "<b>%s</b>: " + "drag to shape the path" ", " + "click to toggle scale/rotation handles" ". " + "(more: Shift, Ctrl, Alt)"), + nodetype); + } + } + else if (!isBSpline) { + s = format_tip(C_("Path node tip", + "<b>%s</b>: " + "drag to shape the path" ", " + "click to select only this node" ". " + "(more: Shift, Ctrl, Alt)"), + nodetype); + } + else { + s = format_tip(C_("Path node tip", + "<b>BSpline node</b> (%.3g power): " + "drag to shape the path" ", " + "click to select only this node" ". " + "(more: Shift, Ctrl, Alt)"), + power); + } + } + + return (s); +} + +Glib::ustring Node::_getDragTip(GdkEventMotion */*event*/) const +{ + Geom::Point dist = position() - _last_drag_origin(); + + Inkscape::Util::Quantity x_q = Inkscape::Util::Quantity(dist[Geom::X], "px"); + Inkscape::Util::Quantity y_q = Inkscape::Util::Quantity(dist[Geom::Y], "px"); + Glib::ustring x = x_q.string(_desktop->namedview->display_units); + Glib::ustring y = y_q.string(_desktop->namedview->display_units); + Glib::ustring ret = format_tip(C_("Path node tip", "Move node by %s, %s"), x.c_str(), y.c_str()); + return ret; +} + +/** + * See also: Handle::handle_type_to_localized_string(NodeType type) + */ +char const *Node::node_type_to_localized_string(NodeType type) +{ + switch (type) { + case NODE_CUSP: + return _("Corner node"); + case NODE_SMOOTH: + return _("Smooth node"); + case NODE_SYMMETRIC: + return _("Symmetric node"); + case NODE_AUTO: + return _("Auto-smooth node"); + default: + return ""; + } +} + +bool Node::_is_line_segment(Node *first, Node *second) +{ + if (!first || !second) return false; + if (first->_next() == second) + return first->_front.isDegenerate() && second->_back.isDegenerate(); + if (second->_next() == first) + return second->_front.isDegenerate() && first->_back.isDegenerate(); + return false; +} + +NodeList::NodeList(SubpathList &splist) + : _list(splist) + , _closed(false) +{ + this->ln_list = this; + this->ln_next = this; + this->ln_prev = this; +} + +NodeList::~NodeList() +{ + clear(); +} + +bool NodeList::empty() +{ + return ln_next == this; +} + +NodeList::size_type NodeList::size() +{ + size_type sz = 0; + for (ListNode *ln = ln_next; ln != this; ln = ln->ln_next) ++sz; + return sz; +} + +bool NodeList::closed() +{ + return _closed; +} + +bool NodeList::degenerate() +{ + return closed() ? empty() : ++begin() == end(); +} + +NodeList::iterator NodeList::before(double t, double *fracpart) +{ + double intpart; + *fracpart = std::modf(t, &intpart); + int index = intpart; + + iterator ret = begin(); + std::advance(ret, index); + return ret; +} + +NodeList::iterator NodeList::before(Geom::PathTime const &pvp) +{ + iterator ret = begin(); + std::advance(ret, pvp.curve_index); + return ret; +} + +NodeList::iterator NodeList::insert(iterator pos, Node *x) +{ + ListNode *ins = pos._node; + x->ln_next = ins; + x->ln_prev = ins->ln_prev; + ins->ln_prev->ln_next = x; + ins->ln_prev = x; + x->ln_list = this; + return iterator(x); +} + +void NodeList::splice(iterator pos, NodeList &list) +{ + splice(pos, list, list.begin(), list.end()); +} + +void NodeList::splice(iterator pos, NodeList &list, iterator i) +{ + NodeList::iterator j = i; + ++j; + splice(pos, list, i, j); +} + +void NodeList::splice(iterator pos, NodeList &/*list*/, iterator first, iterator last) +{ + ListNode *ins_beg = first._node, *ins_end = last._node, *at = pos._node; + for (ListNode *ln = ins_beg; ln != ins_end; ln = ln->ln_next) { + ln->ln_list = this; + } + ins_beg->ln_prev->ln_next = ins_end; + ins_end->ln_prev->ln_next = at; + at->ln_prev->ln_next = ins_beg; + + ListNode *atprev = at->ln_prev; + at->ln_prev = ins_end->ln_prev; + ins_end->ln_prev = ins_beg->ln_prev; + ins_beg->ln_prev = atprev; +} + +void NodeList::shift(int n) +{ + // 1. make the list perfectly cyclic + ln_next->ln_prev = ln_prev; + ln_prev->ln_next = ln_next; + // 2. find new begin + ListNode *new_begin = ln_next; + if (n > 0) { + for (; n > 0; --n) new_begin = new_begin->ln_next; + } else { + for (; n < 0; ++n) new_begin = new_begin->ln_prev; + } + // 3. relink begin to list + ln_next = new_begin; + ln_prev = new_begin->ln_prev; + new_begin->ln_prev->ln_next = this; + new_begin->ln_prev = this; +} + +void NodeList::reverse() +{ + for (ListNode *ln = ln_next; ln != this; ln = ln->ln_prev) { + std::swap(ln->ln_next, ln->ln_prev); + Node *node = static_cast<Node*>(ln); + Geom::Point save_pos = node->front()->position(); + node->front()->setPosition(node->back()->position()); + node->back()->setPosition(save_pos); + } + std::swap(ln_next, ln_prev); +} + +void NodeList::clear() +{ + // ugly but more efficient clearing mechanism + std::vector<ControlPointSelection *> to_clear; + std::vector<std::pair<SelectableControlPoint *, long> > nodes; + long in = -1; + for (iterator i = begin(); i != end(); ++i) { + SelectableControlPoint *rm = static_cast<Node*>(i._node); + if (std::find(to_clear.begin(), to_clear.end(), &rm->_selection) == to_clear.end()) { + to_clear.push_back(&rm->_selection); + ++in; + } + nodes.emplace_back(rm, in); + } + for (size_t i = 0, e = nodes.size(); i != e; ++i) { + to_clear[nodes[i].second]->erase(nodes[i].first, false); + } + std::vector<std::vector<SelectableControlPoint *> > emission; + for (long i = 0, e = to_clear.size(); i != e; ++i) { + emission.emplace_back(); + for (size_t j = 0, f = nodes.size(); j != f; ++j) { + if (nodes[j].second != i) + break; + emission[i].push_back(nodes[j].first); + } + } + + for (size_t i = 0, e = emission.size(); i != e; ++i) { + to_clear[i]->signal_selection_changed.emit(emission[i], false); + } + + for (iterator i = begin(); i != end();) + erase (i++); +} + +NodeList::iterator NodeList::erase(iterator i) +{ + // some gymnastics are required to ensure that the node is valid when deleted; + // otherwise the code that updates handle visibility will break + Node *rm = static_cast<Node*>(i._node); + ListNode *rmnext = rm->ln_next, *rmprev = rm->ln_prev; + ++i; + delete rm; + rmprev->ln_next = rmnext; + rmnext->ln_prev = rmprev; + return i; +} + +// TODO this method is very ugly! +// converting SubpathList to an intrusive list might allow us to get rid of it +void NodeList::kill() +{ + for (SubpathList::iterator i = _list.begin(); i != _list.end(); ++i) { + if (i->get() == this) { + _list.erase(i); + return; + } + } +} + +NodeList &NodeList::get(Node *n) { + return n->nodeList(); +} +NodeList &NodeList::get(iterator const &i) { + return *(i._node->ln_list); +} + + +} // namespace UI +} // namespace Inkscape + +/* + 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 : |