File indexing completed on 2025-02-02 04:54:39

 // SPDX-License-Identifier: GPL-2.0-or-later
 // SPDX-FileCopyrightText: 2018 Kevin Ottens <ervin@kde.org>
 
 #include "strokepainter.h"
 
 #include <QPainter>
 #include <QPainterPath>
 #include <QVector2D>
 
 #include <algorithm>
 #include <cmath>
 using namespace std;
 
 #include "stroke.h"
 
 StrokePainter::StrokePainter(QObject *parent)
     : QObject(parent)
 {
 }
 
 void StrokePainter::render(const Stroke &stroke, QPainter *painter)
 {
     const auto samples = stroke.samples();
     if (samples.size() < 2)
         return;
 
     auto it = samples.cbegin();
     auto lastSample = *it;
     ++it;
 
     auto forwardPoints = QVector<QVector2D>{};
     auto backwardPoints = QVector<QVector2D>{};
 
     while (it != samples.cend()) {
         const auto currentSample = *it;
 
         const auto penWidth = currentSample.width;
 
         const auto currentPos = currentSample.position;
         const auto lastPos = lastSample.position;
 
         const auto direction = currentPos - lastPos;
         const auto ortho = QVector2D(direction.y(), -direction.x()).normalized();
 
         const auto p1 = (lastPos - penWidth * ortho / 2.0f);
         const auto p2 = (lastPos + penWidth * ortho / 2.0f);
         const auto p3 = (currentPos - penWidth * ortho / 2.0f);
         const auto p4 = (currentPos + penWidth * ortho / 2.0f);
 
         int minX = (int)min({p1.x(), p2.x(), p3.x(), p4.x()});
         if (!lowestX || minX < lowestX)
             lowestX = minX;
 
         int maxX = (int)max({p1.x(), p2.x(), p3.x(), p4.x()});
         if (!highestX || maxX > highestX)
             highestX = maxX;
 
         int minY = (int)min({p1.y(), p2.y(), p3.y(), p4.y()});
         if (!lowestY || minY < lowestY)
             lowestY = minY;
 
         int maxY = (int)max({p1.y(), p2.y(), p3.y(), p4.y()});
         if (!highestY || maxY > highestY)
             highestY = maxY;
 
         forwardPoints << p1 << p3;
         backwardPoints << p2 << p4;
 
         lastSample = currentSample;
         ++it;
     }
 
     auto path = QPainterPath();
     path.moveTo(static_cast<qreal>(forwardPoints[0].x()), static_cast<qreal>(forwardPoints[0].y()));
     for (auto it = forwardPoints.cbegin() + 1; it != forwardPoints.cend(); ++it) {
         path.lineTo(static_cast<qreal>(it->x()), static_cast<qreal>(it->y()));
     }
     for (auto it = backwardPoints.crbegin(); it != backwardPoints.crend(); ++it) {
         path.lineTo(static_cast<qreal>(it->x()), static_cast<qreal>(it->y()));
     }
     path.closeSubpath();
     path.setFillRule(Qt::WindingFill);
 
     painter->setPen(Qt::NoPen);
     painter->setBrush(stroke.color());
     painter->drawPath(path);
 }