File indexing completed on 2024-05-12 16:01:37

 /*
  *  SPDX-FileCopyrightText: 2008, 2011 Cyrille Berger <cberger@cberger.net>
  *  SPDX-FileCopyrightText: 2010 Geoffry Song <goffrie@gmail.com>
  *  SPDX-FileCopyrightText: 2017 Scott Petrovic <scottpetrovic@gmail.com>
  *
  *  SPDX-License-Identifier: GPL-2.0-or-later
  */
 
 #include <QXmlStreamReader>
 #include "kis_painting_assistant.h"
 #include "kis_coordinates_converter.h"
 #include "kis_debug.h"
 #include "kis_dom_utils.h"
 #include <kis_canvas2.h>
 #include "kis_tool.h"
 #include "kis_config.h"
 
 #include <KoStore.h>
 
 #include <QGlobalStatic>
 #include <QPen>
 #include <QPainter>
 #include <QPixmapCache>
 #include <QDomElement>
 #include <QDomDocument>
 
 Q_GLOBAL_STATIC(KisPaintingAssistantFactoryRegistry, s_instance)
 
 struct KisPaintingAssistantHandle::Private {
     QList<KisPaintingAssistant*> assistants;
     char handle_type;
 };
 
 KisPaintingAssistantHandle::KisPaintingAssistantHandle(double x, double y) : QPointF(x, y), d(new Private)
 {
 }
 
 KisPaintingAssistantHandle::KisPaintingAssistantHandle(QPointF p) : QPointF(p), d(new Private)
 {
 }
 
 KisPaintingAssistantHandle::KisPaintingAssistantHandle(const KisPaintingAssistantHandle& rhs)
     : QPointF(rhs)
     , KisShared()
     , d(new Private)
 {
     dbgUI << "KisPaintingAssistantHandle ctor";
 }
 
 KisPaintingAssistantHandle& KisPaintingAssistantHandle::operator=(const QPointF &  pt)
 {
     setX(pt.x());
     setY(pt.y());
     return *this;
 }
 
 void KisPaintingAssistantHandle::setType(char type)
 {
     d->handle_type = type;
 }
 
 char KisPaintingAssistantHandle::handleType() const
 {
     return d->handle_type;
 }
 
 KisPaintingAssistant *KisPaintingAssistantHandle::chiefAssistant() const
 {
     return !d->assistants.isEmpty() ? d->assistants.first() : 0;
 }
 
 KisPaintingAssistantHandle::~KisPaintingAssistantHandle()
 {
     Q_ASSERT(d->assistants.empty());
     delete d;
 }
 
 void KisPaintingAssistantHandle::registerAssistant(KisPaintingAssistant* assistant)
 {
     Q_ASSERT(!d->assistants.contains(assistant));
     d->assistants.append(assistant);
 }
 
 void KisPaintingAssistantHandle::unregisterAssistant(KisPaintingAssistant* assistant)
 {
     d->assistants.removeOne(assistant);
     Q_ASSERT(!d->assistants.contains(assistant));
 }
 
 bool KisPaintingAssistantHandle::containsAssistant(KisPaintingAssistant* assistant) const
 {
     return d->assistants.contains(assistant);
 }
 
 void KisPaintingAssistantHandle::mergeWith(KisPaintingAssistantHandleSP handle)
 {
     if(this->handleType()== HandleType::NORMAL || handle.data()->handleType()== HandleType::SIDE) {
         return;
     }
 
 
     Q_FOREACH (KisPaintingAssistant* assistant, handle->d->assistants) {
         if (!assistant->handles().contains(this)) {
             assistant->replaceHandle(handle, this);
         }
     }
 }
 
 void KisPaintingAssistantHandle::uncache()
 {
     Q_FOREACH (KisPaintingAssistant* assistant, d->assistants) {
         assistant->uncache();
     }
 }
 
 struct KisPaintingAssistant::Private {
     Private();
     explicit Private(const Private &rhs);
     KisPaintingAssistantHandleSP reuseOrCreateHandle(QMap<KisPaintingAssistantHandleSP, KisPaintingAssistantHandleSP> &handleMap, KisPaintingAssistantHandleSP origHandle, KisPaintingAssistant *q, bool registerAssistant = true);
     QList<KisPaintingAssistantHandleSP> handles, sideHandles;
 
     KisPaintingAssistantHandleSP topLeft, bottomLeft, topRight, bottomRight, topMiddle, bottomMiddle, rightMiddle, leftMiddle;
 
     // share everything except handles between the clones
     struct SharedData {
         QString id;
         QString name;
         bool isSnappingActive {true};
         bool outlineVisible {true};
         bool isLocal {false};
 
         KisCanvas2* m_canvas {nullptr};
 
         QPixmapCache::Key cached;
         QRect cachedRect; // relative to boundingRect().topLeft()
 
         struct TranslationInvariantTransform {
             qreal m11 {0.0};
             qreal m12 {0.0};
             qreal m21 {0.0};
             qreal m22 {0.0};
 
             TranslationInvariantTransform() { }
             TranslationInvariantTransform(const QTransform& t) : m11(t.m11()), m12(t.m12()), m21(t.m21()), m22(t.m22()) { }
             bool operator==(const TranslationInvariantTransform& b) {
                 return m11 == b.m11 && m12 == b.m12 && m21 == b.m21 && m22 == b.m22;
             }
         } cachedTransform;
 
         QColor assistantGlobalColorCache = QColor(Qt::red);     // color to paint with if a custom color is not set
 
         bool useCustomColor {false};
         QColor assistantCustomColor {KisConfig(true).defaultAssistantsColor()};
     };
 
     QSharedPointer<SharedData> s;
 };
 
 KisPaintingAssistant::Private::Private()
     : s(new SharedData)
 {
 }
 
 KisPaintingAssistant::Private::Private(const Private &rhs)
     : s(rhs.s)
 {
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::Private::reuseOrCreateHandle(QMap<KisPaintingAssistantHandleSP, KisPaintingAssistantHandleSP> &handleMap, KisPaintingAssistantHandleSP origHandle, KisPaintingAssistant *q, bool registerAssistant)
 {
     KisPaintingAssistantHandleSP mappedHandle = handleMap.value(origHandle);
     if (!mappedHandle) {
         if (origHandle) {
             dbgUI << "handle not found in the map, creating a new one...";
             mappedHandle = KisPaintingAssistantHandleSP(new KisPaintingAssistantHandle(*origHandle));
             dbgUI << "done";
             mappedHandle->setType(origHandle->handleType());
             handleMap.insert(origHandle, mappedHandle);
         } else {
             dbgUI << "orig handle is null, not doing anything";
             mappedHandle = KisPaintingAssistantHandleSP();
         }
     }
     if (mappedHandle && registerAssistant) {
         mappedHandle->registerAssistant(q);
     }
     return mappedHandle;
 }
 
 bool KisPaintingAssistant::useCustomColor()
 {
     return d->s->useCustomColor;
 }
 
 void KisPaintingAssistant::setUseCustomColor(bool useCustomColor)
 {
     d->s->useCustomColor = useCustomColor;
 }
 
 void KisPaintingAssistant::setAssistantCustomColor(QColor color)
 {
     d->s->assistantCustomColor = color;
 }
 
 QColor KisPaintingAssistant::assistantCustomColor()
 {
     return d->s->assistantCustomColor;
 }
 
 void KisPaintingAssistant::setAssistantGlobalColorCache(const QColor &color)
 {
     d->s->assistantGlobalColorCache = color;
 }
 
 QColor KisPaintingAssistant::effectiveAssistantColor() const
 {
     return d->s->useCustomColor ? d->s->assistantCustomColor : d->s->assistantGlobalColorCache;
 }
 
 KisPaintingAssistant::KisPaintingAssistant(const QString& id, const QString& name) : d(new Private)
 {
     d->s->id = id;
     d->s->name = name;
     d->s->isSnappingActive = true;
     d->s->outlineVisible = true;
 }
 
 KisPaintingAssistant::KisPaintingAssistant(const KisPaintingAssistant &rhs, QMap<KisPaintingAssistantHandleSP, KisPaintingAssistantHandleSP> &handleMap)
     : d(new Private(*(rhs.d)))
 {
     dbgUI << "creating handles...";
     Q_FOREACH (const KisPaintingAssistantHandleSP origHandle, rhs.d->handles) {
         d->handles << d->reuseOrCreateHandle(handleMap, origHandle, this);
     }
     Q_FOREACH (const KisPaintingAssistantHandleSP origHandle, rhs.d->sideHandles) {
         d->sideHandles << d->reuseOrCreateHandle(handleMap, origHandle, this);
     }
 #define _REUSE_H(name) d->name = d->reuseOrCreateHandle(handleMap, rhs.d->name, this, /* registerAssistant = */ false)
     _REUSE_H(topLeft);
     _REUSE_H(bottomLeft);
     _REUSE_H(topRight);
     _REUSE_H(bottomRight);
     _REUSE_H(topMiddle);
     _REUSE_H(bottomMiddle);
     _REUSE_H(rightMiddle);
     _REUSE_H(leftMiddle);
 #undef _REUSE_H
     dbgUI << "done";
 }
 
 bool KisPaintingAssistant::isSnappingActive() const
 {
     return d->s->isSnappingActive;
 }
 
 void KisPaintingAssistant::setSnappingActive(bool set)
 {
     d->s->isSnappingActive = set;
 }
 
 bool KisPaintingAssistant::canBeLocal() const
 {
     return false;
 }
 
 bool KisPaintingAssistant::isLocal() const
 {
     return d->s->isLocal;
 }
 
 void KisPaintingAssistant::setLocal(bool value)
 {
     d->s->isLocal = value;
 }
 
 
 void KisPaintingAssistant::drawPath(QPainter& painter, const QPainterPath &path, bool isSnappingOn)
 {
 
     QColor paintingColor = effectiveAssistantColor();
 
     if (!isSnappingOn) {
         paintingColor.setAlpha(0.2 * paintingColor.alpha());
     }
 
     painter.save();
     QPen pen_a(paintingColor, 2);
     pen_a.setCosmetic(true);
     painter.setPen(pen_a);
     painter.drawPath(path);
     painter.restore();
 }
 
 void KisPaintingAssistant::drawPreview(QPainter& painter, const QPainterPath &path)
 {
     painter.save();
     QPen pen_a(effectiveAssistantColor(), 1);
     pen_a.setStyle(Qt::SolidLine);
     pen_a.setCosmetic(true);
     painter.setPen(pen_a);
     painter.drawPath(path);
     painter.restore();
 }
 
 void KisPaintingAssistant::initHandles(QList<KisPaintingAssistantHandleSP> _handles)
 {
     Q_ASSERT(d->handles.isEmpty());
     d->handles = _handles;
     Q_FOREACH (KisPaintingAssistantHandleSP handle, _handles) {
         handle->registerAssistant(this);
     }
 }
 
 KisPaintingAssistant::~KisPaintingAssistant()
 {
     Q_FOREACH (KisPaintingAssistantHandleSP handle, d->handles) {
         handle->unregisterAssistant(this);
     }
     if(!d->sideHandles.isEmpty()) {
         Q_FOREACH (KisPaintingAssistantHandleSP handle, d->sideHandles) {
             handle->unregisterAssistant(this);
         }
     }
     delete d;
 }
 
 const QString& KisPaintingAssistant::id() const
 {
     return d->s->id;
 }
 
 const QString& KisPaintingAssistant::name() const
 {
     return d->s->name;
 }
 
 void KisPaintingAssistant::replaceHandle(KisPaintingAssistantHandleSP _handle, KisPaintingAssistantHandleSP _with)
 {
     Q_ASSERT(d->handles.contains(_handle));
     d->handles.replace(d->handles.indexOf(_handle), _with);
     Q_ASSERT(!d->handles.contains(_handle));
     _handle->unregisterAssistant(this);
     _with->registerAssistant(this);
 }
 
 void KisPaintingAssistant::addHandle(KisPaintingAssistantHandleSP handle, HandleType type)
 {
     Q_ASSERT(!d->handles.contains(handle));
     if (HandleType::SIDE == type) {
         d->sideHandles.append(handle);
     } else {
         d->handles.append(handle);
     }
 
     handle->registerAssistant(this);
     handle.data()->setType(type);
 }
 
 QPointF KisPaintingAssistant::viewportConstrainedEditorPosition(const KisCoordinatesConverter* converter, const QSize editorSize)
 {
     QPointF editorDocumentPos = getEditorPosition();
     QPointF editorWidgetPos = converter->documentToWidgetTransform().map(editorDocumentPos);
     QSizeF canvasSize = converter->getCanvasWidgetSize();
     const int padding = 16;
 
     editorWidgetPos.rx() = qBound(0.0,
                                   editorWidgetPos.x(),
                                   canvasSize.width() - (editorSize.width() + padding));
     editorWidgetPos.ry() = qBound(0.0,
                                   editorWidgetPos.y(),
                                   canvasSize.height() - (editorSize.height() + padding));
 
     return converter->widgetToDocument(editorWidgetPos);
 }
 
 void KisPaintingAssistant::drawAssistant(QPainter& gc, const QRectF& updateRect, const KisCoordinatesConverter* converter, bool useCache, KisCanvas2* canvas, bool assistantVisible, bool previewVisible)
 {
     Q_UNUSED(updateRect);
 
     Q_UNUSED(previewVisible);
 
     findPerspectiveAssistantHandleLocation();
 
     if (!useCache) {
         gc.save();
         drawCache(gc, converter, assistantVisible);
         gc.restore();
         return;
     }
 
     const QRect bound = boundingRect();
     if (bound.isEmpty()) {
         return;
     }
 
     const QTransform transform = converter->documentToWidgetTransform();
     const QRect widgetBound = transform.mapRect(bound);
 
     const QRect paintRect = transform.mapRect(bound).intersected(gc.viewport());
     if (paintRect.isEmpty()) return;
 
     QPixmap cached;
     bool found = QPixmapCache::find(d->s->cached, &cached);
 
     if (!(found &&
           d->s->cachedTransform == transform &&
           d->s->cachedRect.translated(widgetBound.topLeft()).contains(paintRect))) {
 
         const QRect cacheRect = gc.viewport().adjusted(-100, -100, 100, 100).intersected(widgetBound);
         Q_ASSERT(!cacheRect.isEmpty());
 
         if (cached.isNull() || cached.size() != cacheRect.size()) {
             cached = QPixmap(cacheRect.size());
         }
 
         cached.fill(Qt::transparent);
         QPainter painter(&cached);
         painter.setRenderHint(QPainter::Antialiasing);
         painter.setWindow(cacheRect);
         drawCache(painter, converter, assistantVisible);
         painter.end();
         d->s->cachedTransform = transform;
         d->s->cachedRect = cacheRect.translated(-widgetBound.topLeft());
         d->s->cached = QPixmapCache::insert(cached);
     }
 
     gc.drawPixmap(paintRect, cached, paintRect.translated(-widgetBound.topLeft() - d->s->cachedRect.topLeft()));
 
 
     if (canvas) {
         d->s->m_canvas = canvas;
     }
 }
 
 void KisPaintingAssistant::uncache()
 {
     d->s->cached = QPixmapCache::Key();
 }
 
 QRect KisPaintingAssistant::boundingRect() const
 {
     QRectF r;
     Q_FOREACH (KisPaintingAssistantHandleSP h, handles()) {
         r = r.united(QRectF(*h, QSizeF(1,1)));
     }
     return r.adjusted(-2, -2, 2, 2).toAlignedRect();
 }
 
 bool KisPaintingAssistant::isAssistantComplete() const
 {
     return true;
 }
 
 void KisPaintingAssistant::transform(const QTransform &transform)
 {
     Q_FOREACH(KisPaintingAssistantHandleSP handle, handles()) {
         if (handle->chiefAssistant() != this) continue;
 
         *handle = transform.map(*handle);
     }
 
     Q_FOREACH(KisPaintingAssistantHandleSP handle, sideHandles()) {
         if (handle->chiefAssistant() != this) continue;
 
         *handle = transform.map(*handle);
     }
 
     uncache();
 }
 
 QByteArray KisPaintingAssistant::saveXml(QMap<KisPaintingAssistantHandleSP, int> &handleMap)
 {
     QByteArray data;
     QXmlStreamWriter xml(&data);
     xml.writeStartDocument();
     xml.writeStartElement("assistant");
     xml.writeAttribute("type",d->s->id);
     xml.writeAttribute("active", QString::number(d->s->isSnappingActive));
     xml.writeAttribute("useCustomColor", QString::number(d->s->useCustomColor));
     xml.writeAttribute("customColor",  KisDomUtils::qColorToQString(d->s->assistantCustomColor));
 
 
 
     saveCustomXml(&xml); // if any specific assistants have custom XML data to save to
 
     // write individual handle data
     xml.writeStartElement("handles");
     Q_FOREACH (const KisPaintingAssistantHandleSP handle, d->handles) {
         int id = handleMap.size();
         if (!handleMap.contains(handle)){
             handleMap.insert(handle, id);
         }
         id = handleMap.value(handle);
         xml.writeStartElement("handle");
         xml.writeAttribute("id", QString::number(id));
         xml.writeAttribute("x", QString::number(double(handle->x()), 'f', 3));
         xml.writeAttribute("y", QString::number(double(handle->y()), 'f', 3));
         xml.writeEndElement();
     }
     xml.writeEndElement();
     if (!d->sideHandles.isEmpty()) { // for vanishing points only
     xml.writeStartElement("sidehandles");
     QMap<KisPaintingAssistantHandleSP, int> sideHandleMap;
     Q_FOREACH (KisPaintingAssistantHandleSP handle, d->sideHandles) {
         int id = sideHandleMap.size();
         sideHandleMap.insert(handle, id);
         xml.writeStartElement("sidehandle");
         xml.writeAttribute("id", QString::number(id));
         xml.writeAttribute("x", QString::number(double(handle->x()), 'f', 3));
         xml.writeAttribute("y", QString::number(double(handle->y()), 'f', 3));
         xml.writeEndElement();
       }
     }
 
     xml.writeEndElement();
     xml.writeEndDocument();
     return data;
 }
 
 void KisPaintingAssistant::saveCustomXml(QXmlStreamWriter* xml)
 {
     Q_UNUSED(xml);
 }
 
 void KisPaintingAssistant::loadXml(KoStore* store, QMap<int, KisPaintingAssistantHandleSP> &handleMap, QString path)
 {
     int id = 0;
     double x = 0.0, y = 0.0;
     store->open(path);
     QByteArray data = store->read(store->size());
     QXmlStreamReader xml(data);
     QMap<int, KisPaintingAssistantHandleSP> sideHandleMap;
     while (!xml.atEnd()) {
         switch (xml.readNext()) {
         case QXmlStreamReader::StartElement:
             if (xml.name() == "assistant") {
 
                 QStringRef active = xml.attributes().value("active");
                 setSnappingActive( (active != "0")  );
 
                 // load custom shared assistant properties
                 if ( xml.attributes().hasAttribute("useCustomColor")) {
                     QStringRef useCustomColor = xml.attributes().value("useCustomColor");
 
                     bool usingColor = false;
                     if (useCustomColor.toString() == "1") {
                         usingColor = true;
                     }
 
 
                     setUseCustomColor(usingColor);
                 }
 
                 if ( xml.attributes().hasAttribute("customColor")) {
                     QStringRef customColor = xml.attributes().value("customColor");
                     setAssistantCustomColor( KisDomUtils::qStringToQColor(customColor.toString()) );
 
                 }
 
             }
 
             loadCustomXml(&xml);
 
             if (xml.name() == "handle") {
                 QString strId = xml.attributes().value("id").toString(),
                         strX = xml.attributes().value("x").toString(),
                         strY = xml.attributes().value("y").toString();
                 if (!strId.isEmpty() && !strX.isEmpty() && !strY.isEmpty()) {
                     id = strId.toInt();
                     x = strX.toDouble();
                     y = strY.toDouble();
                     if (!handleMap.contains(id)) {
                         handleMap.insert(id, new KisPaintingAssistantHandle(x, y));
                     }
                 }
                 addHandle(handleMap.value(id), HandleType::NORMAL);
             } else if (xml.name() == "sidehandle") {
                 QString strId = xml.attributes().value("id").toString(),
                         strX = xml.attributes().value("x").toString(),
                         strY = xml.attributes().value("y").toString();
                 if (!strId.isEmpty() && !strX.isEmpty() && !strY.isEmpty()) {
                     id = strId.toInt();
                     x = strX.toDouble();
                     y = strY.toDouble();
                     if (!sideHandleMap.contains(id)) {
                         sideHandleMap.insert(id, new KisPaintingAssistantHandle(x, y));
                     }
                 }
                 addHandle(sideHandleMap.value(id), HandleType::SIDE);
 
             }
             break;
         default:
             break;
         }
     }
     store->close();
 }
 
 bool KisPaintingAssistant::loadCustomXml(QXmlStreamReader* xml)
 {
     Q_UNUSED(xml);
     return true;
 }
 
 void KisPaintingAssistant::saveXmlList(QDomDocument& doc, QDomElement& assistantsElement,int count)
 {
     if (d->s->id == "ellipse"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "ellipse");
         assistantElement.setAttribute("filename", QString("ellipse%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "spline"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "spline");
         assistantElement.setAttribute("filename", QString("spline%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "perspective"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "perspective");
         assistantElement.setAttribute("filename", QString("perspective%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "vanishing point"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "vanishing point");
         assistantElement.setAttribute("filename", QString("vanishing point%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "infinite ruler"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "infinite ruler");
         assistantElement.setAttribute("filename", QString("infinite ruler%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "parallel ruler"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "parallel ruler");
         assistantElement.setAttribute("filename", QString("parallel ruler%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "concentric ellipse"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "concentric ellipse");
         assistantElement.setAttribute("filename", QString("concentric ellipse%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "fisheye-point"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "fisheye-point");
         assistantElement.setAttribute("filename", QString("fisheye-point%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "ruler"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "ruler");
         assistantElement.setAttribute("filename", QString("ruler%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "two point"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "two point");
         assistantElement.setAttribute("filename", QString("two point%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
     else if (d->s->id == "perspective ellipse"){
         QDomElement assistantElement = doc.createElement("assistant");
         assistantElement.setAttribute("type", "perspective ellipse");
         assistantElement.setAttribute("filename", QString("perspective ellipse%1.assistant").arg(count));
         assistantsElement.appendChild(assistantElement);
     }
 }
 
 void KisPaintingAssistant::findPerspectiveAssistantHandleLocation() {
     QList<KisPaintingAssistantHandleSP> hHandlesList;
     QList<KisPaintingAssistantHandleSP> vHandlesList;
     uint vHole = 0,hHole = 0;
     KisPaintingAssistantHandleSP oppHandle;
     if (d->handles.size() == 4 && d->s->id == "perspective") {
         //get the handle opposite to the first handle
         oppHandle = oppHandleOne();
         //Sorting handles into two list, X sorted and Y sorted into hHandlesList and vHandlesList respectively.
         Q_FOREACH (const KisPaintingAssistantHandleSP handle,d->handles) {
             hHandlesList.append(handle);
             hHole = hHandlesList.size() - 1;
             vHandlesList.append(handle);
             vHole = vHandlesList.size() - 1;
             /*
              sort handles on the basis of X-coordinate
              */
             while(hHole > 0 && hHandlesList.at(hHole -1).data()->x() > handle.data()->x()) {
 #if QT_VERSION >= QT_VERSION_CHECK(5,13,0)
                 hHandlesList.swapItemsAt(hHole - 1, hHole);
 #else
                 hHandlesList.swap(hHole - 1, hHole);
 #endif
                 hHole = hHole - 1;
             }
             /*
              sort handles on the basis of Y-coordinate
              */
             while(vHole > 0 && vHandlesList.at(vHole -1).data()->y() > handle.data()->y()) {
 #if QT_VERSION >= QT_VERSION_CHECK(5,13,0)
                 vHandlesList.swapItemsAt(vHole-1, vHole);
 #else
                 vHandlesList.swap(vHole-1, vHole);
 #endif
                 vHole = vHole - 1;
             }
         }
 
         /*
          give the handles their respective positions
          */
         if(vHandlesList.at(0).data()->x() > vHandlesList.at(1).data()->x()) {
             d->topLeft = vHandlesList.at(1);
             d->topRight= vHandlesList.at(0);
         }
         else {
             d->topLeft = vHandlesList.at(0);
             d->topRight = vHandlesList.at(1);
         }
         if(vHandlesList.at(2).data()->x() > vHandlesList.at(3).data()->x()) {
             d->bottomLeft = vHandlesList.at(3);
             d->bottomRight = vHandlesList.at(2);
         }
         else {
             d->bottomLeft= vHandlesList.at(2);
             d->bottomRight = vHandlesList.at(3);
         }
 
         /*
          find if the handles that should be opposite are actually oppositely positioned
          */
         if (( (d->topLeft == d->handles.at(0).data() && d->bottomRight == oppHandle) ||
               (d->topLeft == oppHandle && d->bottomRight == d->handles.at(0).data()) ||
               (d->topRight == d->handles.at(0).data() && d->bottomLeft == oppHandle) ||
               (d->topRight == oppHandle && d->bottomLeft == d->handles.at(0).data()) ) )
         {}
         else {
             if(hHandlesList.at(0).data()->y() > hHandlesList.at(1).data()->y()) {
                 d->topLeft = hHandlesList.at(1);
                 d->bottomLeft= hHandlesList.at(0);
             }
             else {
                 d->topLeft = hHandlesList.at(0);
                 d->bottomLeft = hHandlesList.at(1);
             }
             if(hHandlesList.at(2).data()->y() > hHandlesList.at(3).data()->y()) {
                 d->topRight = hHandlesList.at(3);
                 d->bottomRight = hHandlesList.at(2);
             }
             else {
                 d->topRight= hHandlesList.at(2);
                 d->bottomRight = hHandlesList.at(3);
             }
 
         }
         /*
          Setting the middle handles as needed
          */
         if(!d->bottomMiddle && !d->topMiddle && !d->leftMiddle && !d->rightMiddle) {
   
             // Before re-adding the handles, clear old ones that have been
             // potentially loaded from disk and not re-associated with the
             // xxxMiddle pointers in d; otherwise those would stay in place.
             if(!d->sideHandles.isEmpty()) {
                 Q_FOREACH (KisPaintingAssistantHandleSP handle, d->sideHandles) {
                     handle->unregisterAssistant(this);
                 }
                 d->sideHandles.clear();
             }
           
             d->bottomMiddle = new KisPaintingAssistantHandle((d->bottomLeft.data()->x() + d->bottomRight.data()->x())*0.5,
                                                              (d->bottomLeft.data()->y() + d->bottomRight.data()->y())*0.5);
             d->topMiddle = new KisPaintingAssistantHandle((d->topLeft.data()->x() + d->topRight.data()->x())*0.5,
                                                           (d->topLeft.data()->y() + d->topRight.data()->y())*0.5);
             d->rightMiddle= new KisPaintingAssistantHandle((d->topRight.data()->x() + d->bottomRight.data()->x())*0.5,
                                                            (d->topRight.data()->y() + d->bottomRight.data()->y())*0.5);
             d->leftMiddle= new KisPaintingAssistantHandle((d->bottomLeft.data()->x() + d->topLeft.data()->x())*0.5,
                                                           (d->bottomLeft.data()->y() + d->topLeft.data()->y())*0.5);
             
             addHandle(d->rightMiddle, HandleType::SIDE);
             addHandle(d->leftMiddle, HandleType::SIDE);
             addHandle(d->bottomMiddle, HandleType::SIDE);
             addHandle(d->topMiddle, HandleType::SIDE);
         }
         else
         {
             d->bottomMiddle.data()->operator =(QPointF((d->bottomLeft.data()->x() + d->bottomRight.data()->x())*0.5,
                                                        (d->bottomLeft.data()->y() + d->bottomRight.data()->y())*0.5));
             d->topMiddle.data()->operator =(QPointF((d->topLeft.data()->x() + d->topRight.data()->x())*0.5,
                                                     (d->topLeft.data()->y() + d->topRight.data()->y())*0.5));
             d->rightMiddle.data()->operator =(QPointF((d->topRight.data()->x() + d->bottomRight.data()->x())*0.5,
                                                       (d->topRight.data()->y() + d->bottomRight.data()->y())*0.5));
             d->leftMiddle.data()->operator =(QPointF((d->bottomLeft.data()->x() + d->topLeft.data()->x())*0.5,
                                                      (d->bottomLeft.data()->y() + d->topLeft.data()->y())*0.5));
         }
 
     }
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::oppHandleOne()
 {
     QPointF intersection(0,0);
     if((QLineF(d->handles.at(0).data()->toPoint(),d->handles.at(1).data()->toPoint()).intersect(QLineF(d->handles.at(2).data()->toPoint(),d->handles.at(3).data()->toPoint()), &intersection) != QLineF::NoIntersection)
             && (QLineF(d->handles.at(0).data()->toPoint(),d->handles.at(1).data()->toPoint()).intersect(QLineF(d->handles.at(2).data()->toPoint(),d->handles.at(3).data()->toPoint()), &intersection) != QLineF::UnboundedIntersection))
     {
         return d->handles.at(1);
     }
     else if((QLineF(d->handles.at(0).data()->toPoint(),d->handles.at(2).data()->toPoint()).intersect(QLineF(d->handles.at(1).data()->toPoint(),d->handles.at(3).data()->toPoint()), &intersection) != QLineF::NoIntersection)
             && (QLineF(d->handles.at(0).data()->toPoint(),d->handles.at(2).data()->toPoint()).intersect(QLineF(d->handles.at(1).data()->toPoint(),d->handles.at(3).data()->toPoint()), &intersection) != QLineF::UnboundedIntersection))
     {
         return d->handles.at(2);
     }
     else
     {
         return d->handles.at(3);
     }
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::topLeft()
 {
     return d->topLeft;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::topLeft() const
 {
     return d->topLeft;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::bottomLeft()
 {
     return d->bottomLeft;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::bottomLeft() const
 {
     return d->bottomLeft;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::topRight()
 {
     return d->topRight;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::topRight() const
 {
     return d->topRight;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::bottomRight()
 {
     return d->bottomRight;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::bottomRight() const
 {
     return d->bottomRight;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::topMiddle()
 {
     return d->topMiddle;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::topMiddle() const
 {
     return d->topMiddle;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::bottomMiddle()
 {
     return d->bottomMiddle;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::bottomMiddle() const
 {
     return d->bottomMiddle;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::rightMiddle()
 {
     return d->rightMiddle;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::rightMiddle() const
 {
     return d->rightMiddle;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::leftMiddle()
 {
     return d->leftMiddle;
 }
 
 const KisPaintingAssistantHandleSP KisPaintingAssistant::leftMiddle() const
 {
     return d->leftMiddle;
 }
 
 const QList<KisPaintingAssistantHandleSP>& KisPaintingAssistant::handles() const
 {
     return d->handles;
 }
 
 QList<KisPaintingAssistantHandleSP> KisPaintingAssistant::handles()
 {
     return d->handles;
 }
 
 const QList<KisPaintingAssistantHandleSP>& KisPaintingAssistant::sideHandles() const
 {
     return d->sideHandles;
 }
 
 QList<KisPaintingAssistantHandleSP> KisPaintingAssistant::sideHandles()
 {
     return d->sideHandles;
 }
 
 
 
 bool KisPaintingAssistant::areTwoPointsClose(const QPointF& pointOne, const QPointF& pointTwo)
 {
     int m_handleSize = 16;
 
     QRectF handlerect(pointTwo - QPointF(m_handleSize * 0.5, m_handleSize * 0.5), QSizeF(m_handleSize, m_handleSize));
     return handlerect.contains(pointOne);
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::closestCornerHandleFromPoint(QPointF point)
 {
     if (!d->s->m_canvas) {
         return 0;
     }
 
 
     if (areTwoPointsClose(point, pixelToView(topLeft()->toPoint()))) {
         return topLeft();
     } else if (areTwoPointsClose(point, pixelToView(topRight()->toPoint()))) {
         return topRight();
     } else if (areTwoPointsClose(point, pixelToView(bottomLeft()->toPoint()))) {
         return bottomLeft();
     } else if (areTwoPointsClose(point, pixelToView(bottomRight()->toPoint()))) {
         return bottomRight();
     }
     return 0;
 }
 
 
 QPointF KisPaintingAssistant::pixelToView(const QPoint pixelCoords) const
 {
     QPointF documentCoord = d->s->m_canvas->image()->pixelToDocument(pixelCoords);
     return d->s->m_canvas->viewConverter()->documentToView(documentCoord);
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::firstLocalHandle() const
 {
     return 0;
 }
 
 KisPaintingAssistantHandleSP KisPaintingAssistant::secondLocalHandle() const
 {
     return 0;
 }
 
 QRectF KisPaintingAssistant::getLocalRect() const
 {
     if (!isLocal() || !firstLocalHandle() || !secondLocalHandle()) {
         return QRectF();
     }
 
     KisPaintingAssistantHandleSP first = firstLocalHandle();
     KisPaintingAssistantHandleSP second = secondLocalHandle();
 
     QPointF topLeft = QPointF(qMin(first->x(), second->x()), qMin(first->y(), second->y()));
     QPointF bottomRight = QPointF(qMax(first->x(), second->x()), qMax(first->y(), second->y()));
 
     QRectF rect(topLeft, bottomRight);
     return rect;
 }
 
 double KisPaintingAssistant::norm2(const QPointF& p)
 {
     return p.x() * p.x() + p.y() * p.y();
 }
 
 QList<KisPaintingAssistantSP> KisPaintingAssistant::cloneAssistantList(const QList<KisPaintingAssistantSP> &list)
 {
     QMap<KisPaintingAssistantHandleSP, KisPaintingAssistantHandleSP> handleMap;
     QList<KisPaintingAssistantSP> clonedList;
     for (auto i = list.begin(); i != list.end(); ++i) {
         clonedList << (*i)->clone(handleMap);
     }
     return clonedList;
 }
 
 
 
 /*
  * KisPaintingAssistantFactory classes
 */
 
 KisPaintingAssistantFactory::KisPaintingAssistantFactory()
 {
 }
 
 KisPaintingAssistantFactory::~KisPaintingAssistantFactory()
 {
 }
 
 KisPaintingAssistantFactoryRegistry::KisPaintingAssistantFactoryRegistry()
 {
 }
 
 KisPaintingAssistantFactoryRegistry::~KisPaintingAssistantFactoryRegistry()
 {
     Q_FOREACH (const QString &id, keys()) {
         delete get(id);
     }
     dbgRegistry << "deleting KisPaintingAssistantFactoryRegistry ";
 }
 
 KisPaintingAssistantFactoryRegistry* KisPaintingAssistantFactoryRegistry::instance()
 {
     return s_instance;
 }