File indexing completed on 2024-06-16 04:15:52

 /*
  * SPDX-FileCopyrightText: 2008 Cyrille Berger <cberger@cberger.net>
  * SPDX-FileCopyrightText: 2010 Geoffry Song <goffrie@gmail.com>
  * SPDX-FileCopyrightText: 2021 Nabil Maghfur Usman <nmaghfurusman@gmail.com>
  *
  *  SPDX-License-Identifier: LGPL-2.0-or-later
  */
 
 #include "TwoPointAssistant.h"
 #include "kis_debug.h"
 #include <klocalizedstring.h>
 
 #include <QPainter>
 #include <QPainterPath>
 #include <QLinearGradient>
 #include <QTransform>
 
 #include <kis_canvas2.h>
 #include <kis_coordinates_converter.h>
 #include <kis_algebra_2d.h>
 #include <kis_dom_utils.h>
 #include <math.h>
 #include <QtCore/qmath.h>
 #include <kis_assert.h>
 
 TwoPointAssistant::TwoPointAssistant()
     : KisPaintingAssistant("two point", i18n("Two point assistant"))
 {
 }
 
 TwoPointAssistant::TwoPointAssistant(const TwoPointAssistant &rhs, QMap<KisPaintingAssistantHandleSP, KisPaintingAssistantHandleSP> &handleMap)
     : KisPaintingAssistant(rhs, handleMap)
     , m_canvas(rhs.m_canvas)
     , m_snapLine(rhs.m_snapLine)
     , m_gridDensity(rhs.m_gridDensity)
     , m_useVertical(rhs.m_useVertical)
     , m_lastUsedPoint(rhs.m_lastUsedPoint)
 {
 }
 
 KisPaintingAssistantSP TwoPointAssistant::clone(QMap<KisPaintingAssistantHandleSP, KisPaintingAssistantHandleSP> &handleMap) const
 {
     return KisPaintingAssistantSP(new TwoPointAssistant(*this, handleMap));
 }
 
 QPointF TwoPointAssistant::project(const QPointF& point, const QPointF& strokeBegin, const bool snapToAny, qreal moveThreshold)
 {
     Q_ASSERT(isAssistantComplete());
 
     QPointF best_pt = point;
     double best_dist = DBL_MAX;
     QList<int> possibleHandles;
 
     // must be above or equal to 0;
     // if useVertical, then last used point must be below 3, because 2 means vertical
     //     and it's the last possible point here (sanity check)
     // if !useVertical, then it must be below 2, because 2 means vertical
     bool isLastUsedPointCorrectNow = m_lastUsedPoint >= 0 && (m_useVertical ? m_lastUsedPoint < 3 : m_lastUsedPoint < 2);
 
     if (isLocal() && handles().size() == 5) {
         // here we can just return since we don't want to do anything
         // so we're returning a NaN
         // but only if we don't have a point/axes it was already using
 
         QRectF rect = getLocalRect();
         bool insideLocalRect = rect.contains(point);
         if (!insideLocalRect && (!isLastUsedPointCorrectNow || !m_hasBeenInsideLocalRect)) {
             return QPointF(qQNaN(), qQNaN());
         } else if (insideLocalRect) {
             m_hasBeenInsideLocalRect = true;
         }
     }
 
     if (!isLastUsedPointCorrectNow && KisAlgebra2D::norm(point - strokeBegin) < moveThreshold) {
         return strokeBegin;
     }
 
     if (!snapToAny && isLastUsedPointCorrectNow) {
         possibleHandles = QList<int>({m_lastUsedPoint});
     } else {
         if (m_useVertical) {
             possibleHandles = QList<int>({0, 1, 2});
         } else {
             possibleHandles = QList<int>({0, 1});
         }
     }
 
     Q_FOREACH (int vpIndex, possibleHandles) {
         QPointF vp = *handles()[vpIndex];
         double dist = 0;
         QPointF pt = QPointF();
         QLineF snapLine = QLineF();
 
         // TODO: Would be a good idea to generalize this whole routine
         // in KisAlgebra2d, as it's all lifted from the vanishing
         // point assistant and parallel ruler assistant, and by
         // extension the perspective assistant...
         qreal dx = point.x() - strokeBegin.x();
         qreal dy = point.y() - strokeBegin.y();
 
         if (vp != *handles()[2]) {
             snapLine = QLineF(vp, strokeBegin);
         } else {
             QLineF vertical = QLineF(*handles()[0],*handles()[1]).normalVector();
             snapLine = QLineF(vertical.p1(), vertical.p2());
             QPointF translation = (vertical.p1()-strokeBegin)*-1.0;
             snapLine = snapLine.translated(translation);
         }
 
         dx = snapLine.dx();
         dy = snapLine.dy();
 
         const qreal dx2 = dx * dx;
         const qreal dy2 = dy * dy;
         const qreal invsqrlen = 1.0 / (dx2 + dy2);
 
         pt = QPointF(dx2 * point.x() + dy2 * snapLine.x1() + dx * dy * (point.y() - snapLine.y1()),
                      dx2 * snapLine.y1() + dy2 * point.y() + dx * dy * (point.x() - snapLine.x1()));
 
         pt *= invsqrlen;
         dist = qAbs(pt.x() - point.x()) + qAbs(pt.y() - point.y());
 
         if (dist < best_dist) {
             best_pt = pt;
             best_dist = dist;
             m_lastUsedPoint = vpIndex;
         }
     }
 
     return best_pt;
 }
 
 void TwoPointAssistant::endStroke()
 {
     m_snapLine = QLineF();
     m_lastUsedPoint = -1;
     KisPaintingAssistant::endStroke();
 }
 
 QPointF TwoPointAssistant::adjustPosition(const QPointF& pt, const QPointF& strokeBegin, const bool snapToAny, qreal moveThresholdPt)
 {
     return project(pt, strokeBegin, snapToAny, moveThresholdPt);
 }
 
 void TwoPointAssistant::adjustLine(QPointF &point, QPointF &strokeBegin)
 {
     QPointF p = project(point, strokeBegin, true, 0.0);
     point = p;
 }
 
 void TwoPointAssistant::drawAssistant(QPainter& gc, const QRectF& updateRect, const KisCoordinatesConverter* converter, bool cached, KisCanvas2* canvas, bool assistantVisible, bool previewVisible)
 {
     Q_UNUSED(updateRect);
     Q_UNUSED(cached);
     gc.save();
     gc.resetTransform();
 
     const QTransform initialTransform = converter->documentToWidgetTransform();
     bool isEditing = false;
     bool showLocal = isLocal() && handles().size() == 5;
 
     if (isEditing) {
         Q_FOREACH (const QPointF* handle, handles()) {
             QPointF h = initialTransform.map(*handle);
             QRectF ellipse = QRectF(QPointF(h.x() -15, h.y() -15), QSizeF(30, 30));
 
             QPainterPath pathCenter;
             pathCenter.addEllipse(ellipse);
             drawPath(gc, pathCenter, isSnappingActive());
 
             // Draw circle to represent center of vision
             if (handles().length() == 3 && handle == handles()[2]) {
                 const QLineF horizon = QLineF(*handles()[0],*handles()[1]);
                 QLineF normal = horizon.normalVector();
                 normal.translate(*handles()[2]-normal.p1());
                 QPointF cov = horizon.center();
                 normal.intersect(horizon,&cov);
                 const QPointF center = initialTransform.map(cov);
                 QRectF center_ellipse = QRectF(QPointF(center.x() -15, center.y() -15), QSizeF(30, 30));
                 QPainterPath pathCenter;
                 pathCenter.addEllipse(center_ellipse);
                 drawPath(gc, pathCenter, isSnappingActive());
             }
         }
 
         if (handles().size() <= 2) {
             QPainterPath path;
             int tempDensity = m_gridDensity * 10; // the vanishing point density seems visibly more dense, hence let's make it less dense
             QRect viewport = gc.viewport();
 
             for (int i = 0; i < handles().size(); i++) {
                 const QPointF p = initialTransform.map(*handles()[i]);
                 for (int currentAngle=0; currentAngle <= 180; currentAngle = currentAngle + tempDensity) {
 
                     // determine the correct angle based on the iteration
                     float xPos = cos(currentAngle * M_PI / 180);
                     float yPos = sin(currentAngle * M_PI / 180);
                     float length = 100;
                     QPointF unit = QPointF(length*xPos, length*yPos);
 
                     // find point
                     QLineF snapLine = QLineF(p, p + unit);
                     if (KisAlgebra2D::intersectLineRect(snapLine, viewport, false)) {
                         // make a line from VP center to edge of canvas with that angle
 
                         path.moveTo(snapLine.p1());
                         path.lineTo(snapLine.p2());
                     }
 
                     QLineF snapLine2 = QLineF(p, p - unit);
                     if (KisAlgebra2D::intersectLineRect(snapLine2, viewport, false)) {
                         // make a line from VP center to edge of canvas with that angle
 
                         path.moveTo(snapLine2.p1());
                         path.lineTo(snapLine2.p2());
                     }
 
 
                 }
 
                 drawPreview(gc, path);//and we draw the preview.
 
             }
         }
 
     }
 
     if (handles().size() >= 2) {
         QPointF mousePos = effectiveBrushPosition(converter, canvas);
         const QPointF p1 = *handles()[0];
         const QPointF p2 = *handles()[1];
         const QRect viewport= gc.viewport();
 
         const QPolygonF localPoly = (isLocal() && handles().size() == 5) ? initialTransform.map(QPolygonF(getLocalRect())) : QPolygonF();
         const QPolygonF viewportAndLocalPoly = !localPoly.isEmpty() ? QPolygonF(QRectF(viewport)).intersected(localPoly) : QRectF(viewport);
 
 
         QPainterPath path;
         QPainterPath previewPath; // part of the preview, instead of the assistant itself
 
         // draw the horizon
         if (assistantVisible == true || isEditing == true) {
             QLineF horizonLine = initialTransform.map(QLineF(p1,p2));
             KisAlgebra2D::cropLineToConvexPolygon(horizonLine, viewportAndLocalPoly, true, true);
             path.moveTo(horizonLine.p1());
             path.lineTo(horizonLine.p2());
         }
 
         // draw the VP-->mousePos lines
         if (isEditing == false && previewVisible == true && isSnappingActive() == true) {
             // draw the line vp <-> mouse even outside of the local rectangle
             // but only if the mouse pos is inside the rectangle
             QLineF snapMouse1 = QLineF(initialTransform.map(p1), mousePos);
             QLineF snapMouse2 = QLineF(initialTransform.map(p2), mousePos);
             KisAlgebra2D::cropLineToConvexPolygon(snapMouse1, viewportAndLocalPoly, false, true);
             KisAlgebra2D::cropLineToConvexPolygon(snapMouse2, viewportAndLocalPoly, false, true);
             previewPath.moveTo(snapMouse1.p1());
             previewPath.lineTo(snapMouse1.p2());
             previewPath.moveTo(snapMouse2.p1());
             previewPath.lineTo(snapMouse2.p2());
         }
 
         // draw the side handle bars
         if (isEditing == true && !sideHandles().isEmpty()) {
             path.moveTo(initialTransform.map(p1));
             path.lineTo(initialTransform.map(*sideHandles()[0]));
             path.lineTo(initialTransform.map(*sideHandles()[1]));
             path.moveTo(initialTransform.map(p2));
             path.lineTo(initialTransform.map(*sideHandles()[2]));
             path.lineTo(initialTransform.map(*sideHandles()[3]));
             path.moveTo(initialTransform.map(p1));
             path.lineTo(initialTransform.map(*sideHandles()[4]));
             path.lineTo(initialTransform.map(*sideHandles()[5]));
             path.moveTo(initialTransform.map(p2));
             path.lineTo(initialTransform.map(*sideHandles()[6]));
             path.lineTo(initialTransform.map(*sideHandles()[7]));
         }
 
         // draw the local rectangle
         if (showLocal && assistantVisible) {
             QPointF p1 = *handles()[(int)LocalFirstHandle];
             QPointF p3 = *handles()[(int)LocalSecondHandle];
             QPointF p2 = QPointF(p1.x(), p3.y());
             QPointF p4 = QPointF(p3.x(), p1.y());
 
             path.moveTo(initialTransform.map(p1));
 
             path.lineTo(initialTransform.map(p2));
             path.lineTo(initialTransform.map(p3));
             path.lineTo(initialTransform.map(p4));
             path.lineTo(initialTransform.map(p1));
         }
 
 
         drawPreview(gc,previewPath);
         drawPath(gc, path, isSnappingActive());
 
         if (handles().size() >= 3 && isSnappingActive()) {
             path = QPainterPath(); // clear
             const QPointF p3 = *handles()[2];
 
             qreal size = 0;
             const QTransform t = localTransform(p1,p2,p3,&size);
             const QTransform inv = t.inverted();
             const QPointF vp_a = t.map(p1);
             const QPointF vp_b = t.map(p2);
 
             if ((vp_a.x() < 0 && vp_b.x() > 0) ||
                 (vp_a.x() > 0 && vp_b.x() < 0)) {
                 if (m_useVertical) {
                     // Draw vertical line, but only if the center is between both VPs
                     QLineF vertical = initialTransform.map(inv.map(QLineF::fromPolar(1,90)));
                     if (!isEditing) vertical.translate(mousePos - vertical.p1());
                     KisAlgebra2D::cropLineToConvexPolygon(vertical, viewportAndLocalPoly, true, true);
                     if (previewVisible) {
                         path.moveTo(vertical.p1());
                         path.lineTo(vertical.p2());
                     }
 
                     if (assistantVisible) {
                         // Display a notch to represent the center of vision
                         path.moveTo(initialTransform.map(inv.map(QPointF(0,vp_a.y()-10))));
                         path.lineTo(initialTransform.map(inv.map(QPointF(0,vp_a.y()+10))));
                     }
                     drawPreview(gc,path);
                     path = QPainterPath(); // clear
                 }
             }
 
             const QPointF upper = QPointF(0,vp_a.y() + size);
             const QPointF lower = QPointF(0,vp_a.y() - size);
 
             // Set up the fading effect for the grid lines
             // Needed so the grid density doesn't look distracting
             QColor color = effectiveAssistantColor();
             QGradient fade = QLinearGradient(initialTransform.map(inv.map(upper)),
                                              initialTransform.map(inv.map(lower)));
             color.setAlphaF(0);
             fade.setColorAt(0.4, effectiveAssistantColor());
             fade.setColorAt(0.5, color);
             fade.setColorAt(0.6, effectiveAssistantColor());
             const QPen pen = gc.pen();
             const QBrush new_brush = QBrush(fade);
             int width = 1;
             const QPen new_pen = QPen(new_brush, width, pen.style());
             gc.setPen(new_pen);
 
             const QList<QPointF> station_points = {upper, lower};
             const QList<QPointF> vanishing_points = {vp_a, vp_b};
 
             // Draw grid lines above and below the horizon
             Q_FOREACH (const QPointF sp, station_points) {
 
                 // Draw grid lines towards each vanishing point
                 Q_FOREACH (const QPointF vp, vanishing_points) {
 
                     // Interval between each grid line, uses grid density specified by user
                     const qreal initial_angle = QLineF(sp, vp).angle();
                     const qreal interval = size*m_gridDensity / cos((initial_angle - 90) * M_PI/180);
                     const QPointF translation = QPointF(interval, 0);
 
                     // Draw grid lines originating from both the left and right of the central vertical line
                     Q_FOREACH (const int dir, QList<int>({-1, 1})) {
 
                         // Limit at 300 grid lines per direction, reasonable even for m_gridDensity=0.1;
                         for (int i = 0; i <= 300; i++) {
                             const QLineF gridline = QLineF(sp + translation * i * dir, vp);
 
                             // Don't bother drawing lines that are nearly parallel to horizon
                             const qreal angle = gridline.angle();
                             if (angle < 0.25 || angle > 359.75 || (angle < 180.25 && angle > 179.75)) {
                                 break;
                             }
 
                             QLineF drawn_gridline = initialTransform.map(inv.map(gridline));
                             KisAlgebra2D::cropLineToConvexPolygon(drawn_gridline, viewportAndLocalPoly, true, false);
 
                             if (assistantVisible || isEditing == true) {
                                 path.moveTo(drawn_gridline.p2());
                                 path.lineTo(drawn_gridline.p1());
                             }
                         }
                     }
                 }
             }
             gc.drawPath(path);
         }
     }
 
     gc.restore();
     //KisPaintingAssistant::drawAssistant(gc, updateRect, converter, cached, canvas, assistantVisible, previewVisible);
 }
 
 void TwoPointAssistant::drawCache(QPainter& gc, const KisCoordinatesConverter *converter, bool assistantVisible)
 {
     Q_UNUSED(gc);
     Q_UNUSED(converter);
     Q_UNUSED(assistantVisible);
     if (!m_canvas || !isAssistantComplete()) {
         return;
     }
 
     if (assistantVisible == false ||   m_canvas->paintingAssistantsDecoration()->isEditingAssistants()) {
         return;
     }
 }
 
 KisPaintingAssistantHandleSP TwoPointAssistant::firstLocalHandle() const
 {
     if (handles().size() > LocalFirstHandle) {
         return handles().at(LocalFirstHandle);
     } else {
         return nullptr;
     }
 }
 
 KisPaintingAssistantHandleSP TwoPointAssistant::secondLocalHandle() const
 {
     if (handles().size() > LocalSecondHandle) {
         return handles().at(LocalSecondHandle);
     } else {
         return nullptr;
     }
 }
 
 QPointF TwoPointAssistant::getDefaultEditorPosition() const
 {
     int centerOfVisionHandle = 2;
     if (handles().size() > centerOfVisionHandle) {
         return *handles().at(centerOfVisionHandle);
     } else if (handles().size() > 0) {
         KIS_SAFE_ASSERT_RECOVER_RETURN_VALUE(false, *handles().at(0));
         return *handles().at(0);
     } else {
         KIS_SAFE_ASSERT_RECOVER_RETURN_VALUE(false, QPointF(0, 0));
         return QPointF(0, 0);
     }
 }
 
 void TwoPointAssistant::setGridDensity(double density)
 {
     m_gridDensity = density;
 }
 
 bool TwoPointAssistant::useVertical()
 {
     return m_useVertical;
 }
 
 void TwoPointAssistant::setUseVertical(bool value)
 {
     m_useVertical = value;
 }
 
 double TwoPointAssistant::gridDensity()
 {
     return m_gridDensity;
 }
 
 QTransform TwoPointAssistant::localTransform(QPointF vp_a, QPointF vp_b, QPointF pt_c, qreal* size)
 {
     QTransform t = QTransform();
     t.rotate(QLineF(vp_a, vp_b).angle());
     t.translate(-pt_c.x(),-pt_c.y());
     const QLineF horizon = QLineF(t.map(vp_a), QPointF(t.map(vp_b).x(),t.map(vp_a).y()));
     *size = sqrt(pow(horizon.length()/2.0,2) - pow(abs(horizon.center().x()),2));
 
     return t;
 }
 
 bool TwoPointAssistant::isAssistantComplete() const
 {
     return handles().size() >= numHandles();
 }
 
 bool TwoPointAssistant::canBeLocal() const
 {
     return true;
 }
 
 void TwoPointAssistant::saveCustomXml(QXmlStreamWriter* xml)
 {
     xml->writeStartElement("gridDensity");
     xml->writeAttribute("value", KisDomUtils::toString( this->gridDensity()));
     xml->writeEndElement();
     xml->writeStartElement("useVertical");
     xml->writeAttribute("value", KisDomUtils::toString( (int)this->useVertical()));
     xml->writeEndElement();
     xml->writeStartElement("isLocal");
     xml->writeAttribute("value", KisDomUtils::toString( (int)this->isLocal()));
     xml->writeEndElement();
 
 }
 
 bool TwoPointAssistant::loadCustomXml(QXmlStreamReader* xml)
 {
     if (xml && xml->name() == "gridDensity") {
         this->setGridDensity((float)KisDomUtils::toDouble(xml->attributes().value("value").toString()));
     }
     if (xml && xml->name() == "useVertical") {
         this->setUseVertical((bool)KisDomUtils::toInt(xml->attributes().value("value").toString()));
     }
     if (xml && xml->name() == "isLocal") {
         this->setLocal((bool)KisDomUtils::toInt(xml->attributes().value("value").toString()));
     }
     return true;
 }
 
 TwoPointAssistantFactory::TwoPointAssistantFactory()
 {
 }
 
 TwoPointAssistantFactory::~TwoPointAssistantFactory()
 {
 }
 
 QString TwoPointAssistantFactory::id() const
 {
     return "two point";
 }
 
 QString TwoPointAssistantFactory::name() const
 {
     return i18n("2 Point Perspective");
 }
 
 KisPaintingAssistant* TwoPointAssistantFactory::createPaintingAssistant() const
 {
     return new TwoPointAssistant;
 }