Qt5 实现雷达及余晖扫描，探测发现障碍物距离及角度

Qt5 实现雷达及余晖扫描，探测发现障碍物距离及角度

本示例主要利用 QPainter实现雷达图及余晖扫描效果，不依赖其他第三方库。显示效果流畅、平滑，不卡顿，可以直接跨平台应用Windows、Android、iMac及iOS系统。

如下是在Android手机上的界面效果图：

源代码工程链接：

https://download.csdn.net/download/u011275054/10867488

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1、总体说明

       该雷达模拟器主要通过QPainter分别绘制刻度线、刻度值、余晖扫描以及障碍物区域几个主要部分。

图中的红色区域为扫描到的障碍物部分，绿色区域为实时扫描部分，设定能够探测到的最大距离为180cm,

检测到障碍物后，显示雷达实时的旋转角度和探测到的距离。

下面逐一进行上代码说明

2、雷达主体部分的绘制

void RadarSimulator::drawRadar(QPainter *painter)
{
    painter->save();
    painter->setPen(pen_draw);

    painter->translate(width/2,0);
    double dOrigpos = height-height*0.074;
    painter->drawArc(-(width-width*0.0825)/2, dOrigpos-(width-width*0.0825)/2,(width-width*0.0825),(width-width*0.0825),0*16,180* 16);
    painter->drawArc(-(width-width*0.27)/2,dOrigpos-(width-width*0.27)/2,(width-width*0.27),(width-width*0.27),0*16,180* 16);
    painter->drawArc(-(width-width*0.479)/2,dOrigpos-(width-width*0.479)/2,(width-width*0.479),(width-width*0.479),0*16,180* 16);
    painter->drawArc(-(width-width*0.687)/2,dOrigpos-(width-width*0.687)/2,(width-width*0.687),(width-width*0.687),0*16,180* 16);
    painter->drawArc(-(width-width*0.887)/2,dOrigpos-(width-width*0.887)/2,(width-width*0.887),(width-width*0.887),0*16,180* 16);
    painter->restore();

    painter->save();
    painter->setPen(pen_draw);
    painter->translate(width/2,height-height*0.074);

    painter->drawLine(-width/2,0,width/2,0);
    double dRadius = width/2*0.96;

    painter->drawLine(0,0,(-dRadius)*qCos(qDegreesToRadians(30.0)), (-dRadius)*qSin(qDegreesToRadians(30.0)));
    painter->drawLine(0,0,(-dRadius)*qCos(qDegreesToRadians(60.0)), (-dRadius)*qSin(qDegreesToRadians(60.0)));
    painter->drawLine(0,0,(-dRadius)*qCos(qDegreesToRadians(90.0)), (-dRadius)*qSin(qDegreesToRadians(90.0)));
    painter->drawLine(0,0,(-dRadius)*qCos(qDegreesToRadians(120.0)),(-dRadius)*qSin(qDegreesToRadians(120.0)));
    painter->drawLine(0,0,(-dRadius)*qCos(qDegreesToRadians(150.0)),(-dRadius)*qSin(qDegreesToRadians(150.0)));
    painter->drawLine((-dRadius)*qCos(qDegreesToRadians(30.0)),0,dRadius,0);
    painter->restore();
}

3、雷达实时扫描线部分：

void RadarSimulator::drawLine()
{
    QPainter *painter = new QPainter(this);
    painter->save();

    QPen pen;
    QColor color(30,250,60);
    pen.setWidthF(16);
    pen.setColor(color); //添加线的颜色
    painter->setPen(pen);
    painter->translate(width/2,height-height*0.074);
    // draws the line according to the angle
    //painter->drawLine(0,0,(height-height*0.12)*qCos(qDegreesToRadians((double)iAngle)),-(height-height*0.12)*qSin(qDegreesToRadians((double)iAngle)));

    if(bRecyle){
        veclines.clear();
        bRecyle = false;
        bNeedErase = true;
    }
    if(veclines.size() >= 30){
        veclines.pop_front();
    }
    QLineF line(0, 0,(height-height*0.12)*qCos(qDegreesToRadians((double)iAngle)),
                -(height-height*0.12)*qSin(qDegreesToRadians((double)iAngle)));
    veclines.push_back(line);
   //qDebug("***DrawLine:Angle:%d", iAngle);
    int line_cnt = veclines.size();
    for(int num = 0; num < line_cnt; num++)
    {
        float opc = 0.3;
        if(num != 0){
          opc = (float)2.0*num / line_cnt;
          if(opc <= 0.3)
              opc = 0.3;
        }
        painter->setOpacity(opc);
        painter->drawLine(veclines[num]);
    }

   // painter->drawLines(veclines);

    painter->restore();
    delete(painter);
}

4、绘制扫描障碍物区域部分：

void RadarSimulator::drawObject()
{
    QPainter *painter = new QPainter(this);
    painter->save();
    QPen pen;
    QColor color(255,10,10);
    pen.setWidthF(16);
    pen.setColor(color); //添加线的颜色
    painter->setPen(pen);

    painter->translate(width/2,height-height*0.074); // moves the starting coordinats to new location
    float pixsDistance = iDistance*((height-height*0.1666)*1/180); // covers the distance from the sensor from cm to pixels
    // limiting the range to 40 cms

    if(iDistance<180 && iDistance > 0)
    {
        if(bNeedErase){
            vecObjlines.clear();
            bNeedErase = false;
        }

        QLineF line(pixsDistance*qCos(qDegreesToRadians((double)iAngle)),
                    -pixsDistance*qSin(qDegreesToRadians((double)iAngle)),
                    (width-width*0.538)*qCos(qDegreesToRadians((double)iAngle)),
                    -(width-width*0.538)*qSin(qDegreesToRadians((double)iAngle)));
        vecObjlines.push_back(line);
    }

    int line_cnt = vecObjlines.size();
    for(int num = 0; num < line_cnt; num++)
    {
        float opc = 0.3;
        if(num != 0){
          opc = (float)2.0*num / line_cnt;
          if(opc <= 0.3)
              opc = 0.3;
        }
        painter->setOpacity(opc);
        painter->drawLine(vecObjlines[num]);
    }

   // painter->drawLines(vecObjlines);
    painter->restore();
    delete(painter);
}

5、绘制检测到的障碍物距离、角度数值部分

void RadarSimulator::drawText(QPainter *painter)
{
    painter->save();
    painter->setBrush(Qt::black);
    painter->drawRect(0,height-height*0.070,width,height*0.070);
    painter->restore();

    painter->save();
    QString noObject;
    if(iDistance>180 || iDistance <=  2) {
        noObject = "超出范围";
    }
    else {
        noObject = "已探测到";
    }

    painter->setPen(pen_draw);
    painter->setFont(font_txt);
    painter->drawText(width-width*0.4754, height-height*0.0833, "20cm");
    painter->drawText(width-width*0.3854, height-height*0.0833, "60cm");
    painter->drawText(width-width*0.281,  height-height*0.0833, "100cm");
    painter->drawText(width-width*0.177,  height-height*0.0833, "140cm");
    painter->drawText(width-width*0.0799, height-height*0.0833, "180cm");

    painter->setFont(font_Reslt);
    painter->drawText(width-width*0.915, height-height*0.0260, "目标: " + noObject);
    QString angle_ = QString::number(iAngle);
    painter->drawText(width-width*0.53, height-height*0.0260,  "角度: " + angle_ +" °");
    QString dis = QString::number(iDistance);
    painter->drawText(width-width*0.30, height-height*0.0260,  "距离: " + dis + " cm");
    painter->restore();

    painter->save();
    painter->setPen(pen_draw);
    painter->setFont(font_txt);
    painter->translate((width-width*0.5094)+width/2*qCos(qDegreesToRadians(30.0)),(height-height*0.0700)-width/2*qSin(qDegreesToRadians(30.0)));
    painter->rotate(-qDegreesToRadians(-60.0));
    painter->drawText(0, 0, "30°");
    painter->restore();

    painter->save();
    painter->setPen(pen_draw);
    painter->setFont(font_txt);
    painter->translate((width-width*0.509)+width/2*qCos(qDegreesToRadians(60.0)),(height-height*0.0650)-width/2*qSin(qDegreesToRadians(60.0)));
    painter->rotate(-qDegreesToRadians(-30.0));
    painter->drawText(0,0, "60°");
    painter->restore();

    painter->save();
    painter->setPen(pen_draw);
    painter->setFont(font_txt);
    painter->translate((width-width*0.507)+width/2*qCos(qDegreesToRadians(90.0)),(height-height*0.0433)-width/2*qSin(qDegreesToRadians(90.0)));
    painter->rotate(qDegreesToRadians(0.0));
    painter->drawText(0,0, "90°");
    painter->restore();

    painter->save();
    painter->setPen(pen_draw);
    painter->setFont(font_txt);
    painter->translate(width-width*0.503+width/2*qCos(qDegreesToRadians(120.0)),(height-height*0.06129)-width/2*qSin(qDegreesToRadians(120.0)));
    painter->rotate(qDegreesToRadians(-30.0));
    painter->drawText(0,0, "120°");
    painter->restore();

    painter->save();
    painter->setPen(pen_draw);
    painter->setFont(font_txt);
    painter->translate((width-width*0.5104)+width/2*qCos(qDegreesToRadians(150.0)),(height-height*0.0574)-width/2*qSin(qDegreesToRadians(150.0)));
    painter->rotate(qDegreesToRadians(-60.0));
    painter->drawText(0,0, "150°");
    painter->restore();

}