QT绘制心形图案二

Posted 2020-12-02 liuxianglei

本来打算用绘制贝塞尔曲线的方法绘制心形，可是本数学渣怎么都搞不定那几个控制点坐标。研究了一上午，通过lineTo方法，最终还是绘制出封闭的心形图。还收获了意外的效果。

看来就差个女朋友，给她看了。

代码如下：

.h文件

 1 #pragma once
 2 
 3 #include <QtWidgets/QDialog>
 4 #include "ui_heart.h"
 5 #include <Qpainter>
 6 class Heart : public QDialog
 7 {
 8     Q_OBJECT
 9 public:
10     Heart(QWidget *parent = Q_NULLPTR);
11 protected:
12     void paintEvent(QPaintEvent *);
13 private:
14     Ui::HeartClass ui;
15 };

.cpp文件

 1 #include "heart.h"
 2 
 3 Heart::Heart(QWidget *parent): QDialog(parent)
 4 {
 5     ui.setupUi(this);
 6 }
 7 
 8 void Heart::paintEvent(QPaintEvent *event)
 9 {
10     double k = 10;
11     QPainter painter(this);
12     painter.setRenderHint(QPainter::Antialiasing, true);
13     QColor my_color(237, 162, 255, 255);
14     QBrush my_brush(my_color);
15     painter.setPen(Qt::red);
16     /*painter.setBrush(my_brush);*/
17     painter.translate(this->width()/2, this->height()/2);
18     QPainterPath polygonPath;
19     polygonPath.setFillRule(Qt::WindingFill);
20     float x = 16 * k * sin(0.0)*sin(0.0)*sin(0.0);
21     float y = 13 * k * cos(0.0) - 5 * k*cos(0.0) - 2 * k*cos(0.0) - cos(0.0);
22     polygonPath.moveTo(x, -y);
23     for (double t = 0.01; t < 100; t += 0.05)
24     {
25         x = 16 * k * sin(k*t)*sin(k*t)*sin(k*t);
26         y = 13 * k * cos(k*t) - 5 * k * cos(2 * k * t) - 2 * k * cos(3 * k * t) - cos(4 * k * t);
27         polygonPath.lineTo(x, -y);
28         /*painter.drawPoint(x,-y);
29         painter.drawLine(0,0,x,-y);    
30         painter.drawLine(0,0,x+100,-y);*/    
31     }
32     painter.drawPath(polygonPath);
33 }

效果图