QT下的雷达扫描图

#include <QPainter> #include <QPen> #include <QDebug> #include <QLinearGradient> #include <QTimer> #include <QTime> #include "widget.h" #include "ui_widget.h" Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget) { ui->setupUi(this); this->setStyleSheet("background-color:black");//设置窗口背景色为黑色 timer = new QTimer(); connect(timer,SIGNAL(timeout()),this,SLOT(timerTimeOut())); timer->start(10); } Widget::~Widget() { delete ui; } void Widget::resizeEvent(QResizeEvent *event) { if(this->width() > this->height()){ point = QPoint((this->width()-this->height())/2+(this->height()-12)/2,this->height()/2); i_diameter = this->height()-12; }else{ point = QPoint(this->width()/2,(this->height()-this->width())/2+(this->width()-12)/2); i_diameter = this->width()-12; } } void Widget::timerTimeOut() { timer->start(10); d_angle += 3.14/720; if(d_angle >= 6.28){ d_angle = 0; } update(); } void Widget::paintEvent(QPaintEvent *event) { QPainter p_painter(this); //反锯齿 p_painter.setRenderHint(QPainter::Antialiasing); p_painter.drawPixmap(0,0,this->width(),this->height(),paintWidget()); QWidget::paintEvent(event); } QPixmap Widget::paintWidget() { QPixmap pixmap(this->width(),this->height()); QPainter p_painter(&pixmap); QPen pen; QTime timedebug; timedebug.start(); //反锯齿 p_painter.setRenderHint(QPainter::Antialiasing); pixmap.fill(Qt::black); pen.setColor(Qt::green); p_painter.setPen(pen); pen.setColor(Qt::gray); p_painter.setPen(pen); p_painter.drawLine(point.x(),point.y()-i_diameter/2-10,point.x(),point.y()+i_diameter/2+10);//画坐标 p_painter.drawLine(point.x()-i_diameter/2-10,point.y(),point.x()+i_diameter/2+10,point.y()); pen.setColor(Qt::green); p_painter.setPen(pen); for(int i=0; i<6; i++){ p_painter.drawEllipse(point.x()-i_diameter*0.2*i/2,point.y()-i_diameter*0.2*i/2,i_diameter*0.2*i,i_diameter*0.2*i); } QConicalGradient conical_gradient(point,(6.28-d_angle)/6.28*720);//定义圆心和渐变的角度 conical_gradient.setColorAt(0,Qt::green); conical_gradient.setColorAt(0.2,QColor(255,255,255,0)); p_painter.setBrush(conical_gradient); p_painter.drawEllipse(point.x()-i_diameter/2,point.y()-i_diameter/2,i_diameter,i_diameter); qDebug()<<"time_end="<<timedebug.elapsed()<<"ms"; return pixmap; }