/** @file * Control point that is dragged during path drag */ /* Authors: * Krzysztof KosiĆski <tweenk.pl@gmail.com> * * Copyright (C) 2009 Authors * Released under GNU GPL, read the file 'COPYING' for more information */ #include <glib/gi18n.h> #include <2geom/bezier-curve.h> #include "desktop.h" #include "ui/tool/control-point-selection.h" #include "ui/tool/curve-drag-point.h" #include "ui/tool/event-utils.h" #include "ui/tool/multi-path-manipulator.h" #include "ui/tool/path-manipulator.h" #include "ui/tool/node.h" namespace Inkscape { namespace UI { /** * @class CurveDragPoint * An invisible point used to drag curves. This point is used by PathManipulator to allow editing * of path segments by dragging them. It is defined in a separate file so that the node tool * can check if the mouseovered control point is a curve drag point and update the cursor * accordingly, without the need to drag in the full PathManipulator header. */ // This point should be invisible to the user - use the invisible_cset from control-point.h // TODO make some methods from path-manipulator.cpp public so that this point doesn't have // to be declared as a friend bool CurveDragPoint::_drags_stroke = false; CurveDragPoint::CurveDragPoint(PathManipulator &pm) : ControlPoint(pm._multi_path_manipulator._path_data.node_data.desktop, Geom::Point(), Gtk::ANCHOR_CENTER, SP_CTRL_SHAPE_CIRCLE, 1.0, &invisible_cset, pm._multi_path_manipulator._path_data.dragpoint_group) , _pm(pm) { setVisible(false); } bool CurveDragPoint::_eventHandler(GdkEvent *event) { // do not process any events when the manipulator is empty if (_pm.empty()) { setVisible(false); return false; } return ControlPoint::_eventHandler(event); } 00057 bool CurveDragPoint::grabbed(GdkEventMotion */*event*/) { _pm._selection.hideTransformHandles(); NodeList::iterator second = first.next(); // move the handles to 1/3 the length of the segment for line segments if (first->front()->isDegenerate() && second->back()->isDegenerate()) { // delta is a vector equal 1/3 of distance from first to second Geom::Point delta = (second->position() - first->position()) / 3.0; first->front()->move(first->front()->position() + delta); second->back()->move(second->back()->position() - delta); _pm.update(); } return false; } 00075 void CurveDragPoint::dragged(Geom::Point &new_pos, GdkEventMotion *) { NodeList::iterator second = first.next(); // Magic Bezier Drag Equations follow! // "weight" describes how the influence of the drag should be distributed // among the handles; 0 = front handle only, 1 = back handle only. double weight, t = _t; if (t <= 1.0 / 6.0) weight = 0; else if (t <= 0.5) weight = (pow((6 * t - 1) / 2.0, 3)) / 2; else if (t <= 5.0 / 6.0) weight = (1 - pow((6 * (1-t) - 1) / 2.0, 3)) / 2 + 0.5; else weight = 1; Geom::Point delta = new_pos - position(); Geom::Point offset0 = ((1-weight)/(3*t*(1-t)*(1-t))) * delta; Geom::Point offset1 = (weight/(3*t*t*(1-t))) * delta; first->front()->move(first->front()->position() + offset0); second->back()->move(second->back()->position() + offset1); _pm.update(); } void CurveDragPoint::ungrabbed(GdkEventButton *) { _pm._updateDragPoint(_desktop->d2w(position())); _pm._commit(_("Drag curve")); _pm._selection.restoreTransformHandles(); } 00104 bool CurveDragPoint::clicked(GdkEventButton *event) { // This check is probably redundant if (!first || event->button != 1) return false; // the next iterator can be invalid if we click very near the end of path NodeList::iterator second = first.next(); if (!second) return false; // insert nodes on Ctrl+Alt+click if (held_control(*event) && held_alt(*event)) { _insertNode(false); return true; } if (held_shift(*event)) { // if both nodes of the segment are selected, deselect; // otherwise add to selection if (first->selected() && second->selected()) { _pm._selection.erase(first.ptr()); _pm._selection.erase(second.ptr()); } else { _pm._selection.insert(first.ptr()); _pm._selection.insert(second.ptr()); } } else { // without Shift, take selection _pm._selection.clear(); _pm._selection.insert(first.ptr()); _pm._selection.insert(second.ptr()); } return true; } 00137 bool CurveDragPoint::doubleclicked(GdkEventButton *event) { if (event->button != 1 || !first || !first.next()) return false; _insertNode(true); return true; } void CurveDragPoint::_insertNode(bool take_selection) { // The purpose of this call is to make way for the just created node. // Otherwise clicks on the new node would only work after the user moves the mouse a bit. // PathManipulator will restore visibility when necessary. setVisible(false); NodeList::iterator inserted = _pm.subdivideSegment(first, _t); if (take_selection) { _pm._selection.clear(); } _pm._selection.insert(inserted.ptr()); _pm.update(); _pm._commit(_("Add node")); } Glib::ustring CurveDragPoint::_getTip(unsigned state) { if (_pm.empty()) return ""; if (!first || !first.next()) return ""; bool linear = first->front()->isDegenerate() && first.next()->back()->isDegenerate(); if (state_held_shift(state)) { return C_("Path segment tip", "<b>Shift</b>: click to toggle segment selection"); } if (state_held_control(state) && state_held_alt(state)) { return C_("Path segment tip", "<b>Ctrl+Alt</b>: click to insert a node"); } if (linear) { return C_("Path segment tip", "<b>Linear segment</b>: drag to convert to a Bezier segment, " "doubleclick to insert node, click to select (more: Shift, Ctrl+Alt)"); } else { return C_("Path segment tip", "<b>Bezier segment</b>: drag to shape the segment, doubleclick to insert node, " "click to select (more: Shift, Ctrl+Alt)"); } } } // 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:encoding=utf-8:textwidth=99 :