File indexing completed on 2024-05-12 15:56:50

 /* This file is part of the KDE project
  * SPDX-FileCopyrightText: 2008-2009 Jan Hambrecht <jaham@gmx.net>
  *
  * SPDX-License-Identifier: LGPL-2.0-or-later
  */
 
 #include "KoSnapGuide.h"
 #include "KoSnapProxy.h"
 #include "KoSnapStrategy.h"
 
 #include <KoPathShape.h>
 #include <KoPathPoint.h>
 #include <KoViewConverter.h>
 #include <KoCanvasBase.h>
 
 #include <QPainter>
 #include <QPainterPath>
 
 #include <math.h>
 #include "kis_pointer_utils.h"
 
 class Q_DECL_HIDDEN KoSnapGuide::Private
 {
 public:
     Private(KoCanvasBase *parentCanvas)
         : canvas(parentCanvas), additionalEditedShape(0), currentStrategy(0),
         active(true),
         snapDistance(10)
     {
     }
 
     ~Private()
     {
         strategies.clear();
     }
 
     KoCanvasBase *canvas;
     KoShape *additionalEditedShape;
 
     typedef QSharedPointer<KoSnapStrategy> KoSnapStrategySP;
     typedef QList<KoSnapStrategySP> StrategiesList;
     StrategiesList strategies;
     KoSnapStrategySP currentStrategy;
 
     KoSnapGuide::Strategies usedStrategies;
     bool active;
     int snapDistance;
     QList<KoPathPoint*> ignoredPoints;
     QList<KoShape*> ignoredShapes;
 };
 
 KoSnapGuide::KoSnapGuide(KoCanvasBase *canvas)
     : d(new Private(canvas))
 {
     d->strategies.append(toQShared(new GridSnapStrategy()));
     d->strategies.append(toQShared(new NodeSnapStrategy()));
     d->strategies.append(toQShared(new OrthogonalSnapStrategy()));
     d->strategies.append(toQShared(new ExtensionSnapStrategy()));
     d->strategies.append(toQShared(new IntersectionSnapStrategy()));
     d->strategies.append(toQShared(new BoundingBoxSnapStrategy()));
 }
 
 KoSnapGuide::~KoSnapGuide()
 {
 }
 
 void KoSnapGuide::setAdditionalEditedShape(KoShape *shape)
 {
     d->additionalEditedShape = shape;
 }
 
 KoShape *KoSnapGuide::additionalEditedShape() const
 {
     return d->additionalEditedShape;
 }
 
 void KoSnapGuide::enableSnapStrategy(Strategy type, bool value)
 {
     if (value) {
         d->usedStrategies |= type;
     } else {
         d->usedStrategies &= ~type;
     }
 }
 
 bool KoSnapGuide::isStrategyEnabled(Strategy type) const
 {
     return d->usedStrategies & type;
 }
 
 void KoSnapGuide::enableSnapStrategies(Strategies strategies)
 {
     d->usedStrategies = strategies;
 }
 
 KoSnapGuide::Strategies KoSnapGuide::enabledSnapStrategies() const
 {
     return d->usedStrategies;
 }
 
 bool KoSnapGuide::addCustomSnapStrategy(KoSnapStrategy *customStrategy)
 {
     if (!customStrategy || customStrategy->type() != CustomSnapping)
         return false;
 
     d->strategies.append(toQShared(customStrategy));
     return true;
 }
 
 void KoSnapGuide::overrideSnapStrategy(Strategy type, KoSnapStrategy *strategy)
 {
     for (auto it = d->strategies.begin(); it != d->strategies.end(); /*noop*/) {
         if ((*it)->type() == type) {
             if (strategy) {
                 *it = toQShared(strategy);
             } else {
                 it = d->strategies.erase(it);
             }
             return;
         } else {
             ++it;
         }
     }
 
     if (strategy) {
         d->strategies.append(toQShared(strategy));
     }
 }
 
 void KoSnapGuide::enableSnapping(bool on)
 {
     d->active = on;
 }
 
 bool KoSnapGuide::isSnapping() const
 {
     return d->active;
 }
 
 void KoSnapGuide::setSnapDistance(int distance)
 {
     d->snapDistance = qAbs(distance);
 }
 
 int KoSnapGuide::snapDistance() const
 {
     return d->snapDistance;
 }
 
 QPointF KoSnapGuide::snap(const QPointF &mousePosition, const QPointF &dragOffset, Qt::KeyboardModifiers modifiers)
 {
     QPointF pos = mousePosition + dragOffset;
     pos = snap(pos, modifiers);
     return pos - dragOffset;
 }
 
 QPointF KoSnapGuide::snap(const QPointF &mousePosition, Qt::KeyboardModifiers modifiers)
 {
     d->currentStrategy.clear();
 
     if (! d->active || (modifiers & Qt::ShiftModifier))
         return mousePosition;
 
     KoSnapProxy proxy(this);
 
     qreal minDistance = HUGE_VAL;
 
     qreal maxSnapDistance = d->canvas->viewConverter()->viewToDocument(QSizeF(d->snapDistance,
                 d->snapDistance)).width();
 
     foreach (Private::KoSnapStrategySP strategy, d->strategies) {
         if (d->usedStrategies & strategy->type() ||
             strategy->type() == GridSnapping ||
             strategy->type() == CustomSnapping) {
 
             if (! strategy->snap(mousePosition, &proxy, maxSnapDistance))
                 continue;
 
             QPointF snapCandidate = strategy->snappedPosition();
             qreal distance = KoSnapStrategy::squareDistance(snapCandidate, mousePosition);
             if (distance < minDistance) {
                 d->currentStrategy = strategy;
                 minDistance = distance;
             }
         }
     }
 
     if (! d->currentStrategy)
         return mousePosition;
 
     return d->currentStrategy->snappedPosition();
 }
 
 QRectF KoSnapGuide::boundingRect()
 {
     QRectF rect;
 
     if (d->currentStrategy) {
         rect = d->currentStrategy->decoration(*d->canvas->viewConverter()).boundingRect();
         return rect.adjusted(-2, -2, 2, 2);
     } else {
         return rect;
     }
 }
 
 void KoSnapGuide::paint(QPainter &painter, const KoViewConverter &converter)
 {
     if (! d->currentStrategy || ! d->active)
         return;
 
     QPainterPath decoration = d->currentStrategy->decoration(converter);
 
     painter.setBrush(Qt::NoBrush);
 
     QPen whitePen(Qt::white, 0);
     whitePen.setStyle(Qt::SolidLine);
     painter.setPen(whitePen);
     painter.drawPath(decoration);
 
     QPen redPen(Qt::red, 0);
     redPen.setStyle(Qt::DotLine);
     painter.setPen(redPen);
     painter.drawPath(decoration);
 }
 
 KoCanvasBase *KoSnapGuide::canvas() const
 {
     return d->canvas;
 }
 
 void KoSnapGuide::setIgnoredPathPoints(const QList<KoPathPoint*> &ignoredPoints)
 {
     d->ignoredPoints = ignoredPoints;
 }
 
 QList<KoPathPoint*> KoSnapGuide::ignoredPathPoints() const
 {
     return d->ignoredPoints;
 }
 
 void KoSnapGuide::setIgnoredShapes(const QList<KoShape*> &ignoredShapes)
 {
     d->ignoredShapes = ignoredShapes;
 }
 
 QList<KoShape*> KoSnapGuide::ignoredShapes() const
 {
     return d->ignoredShapes;
 }
 
 void KoSnapGuide::reset()
 {
     d->currentStrategy.clear();
     d->additionalEditedShape = 0;
     d->ignoredPoints.clear();
     d->ignoredShapes.clear();
     // remove all custom strategies
     int strategyCount = d->strategies.count();
     for (int i = strategyCount-1; i >= 0; --i) {
         if (d->strategies[i]->type() == CustomSnapping) {
             d->strategies.removeAt(i);
         }
     }
 }