QT实现贪吃蛇游戏代码详解

2024-04-02 19:55

短信预约 -IT技能 免费直播动态提醒

一、新建一个Qt项目

新建Qt Widgets Application，项目名称为HappySnake，基类选择QWidget，类名默认

二、添加要用到的头文件


#include <QKeyEvent>
#include <QRectF>
#include <QPainter>
#include <QPen>
#include <QBrush>
#include <QDebug>
#include <QTimer>
#include <QTime>

三、写类声明信息

贪吃蛇的本体使用小方框来代替
使用QList类来保存贪吃蛇的本体
使用定时器来设定刷新的时间
使用随机函数生成奖励的节点
使用paintEvent来进行绘图
keyPressEvent来监测按键的按下，控制贪吃蛇的移动


class Widget : public QWidget
{
    Q_OBJECT
 
public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();
protected:
    void paintEvent(QPaintEvent *);
    void keyPressEvent(QKeyEvent *);
 
private:
    void addTopRectF();
    void addDownRectF();
    void addLeftRectF();
    void addRightRectF();
    void deleteLastRectF();
    bool snakeStrike();
    enum Move{Left,Right,Up,Down};
protected slots:
    void timeOut();
    void rewardTimeOut();
 
private:
    Ui::Widget *ui;
    QList<QRectF> snake;//贪吃蛇本体
    int snakeNodeWidth = 10;
    int snakeNodeHeight = 10;
    QTimer *timer;
    QTimer *rewardTimer;
    int time = 100;
    int moveFlage = Up;
    bool gameOver = false;
    bool gameStart = false;
    QList<QRectF> rewardNode;//奖励节点
 
};

四、对类函数的实现

构造函数


Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
    resize(480,500);
    //设置窗体背景色为黑色
    setStyleSheet("QWidget{background:black}");
    setWindowOpacity(0.8);//设置窗口的透明度
 
    snake.append(QRectF(200,500,snakeNodeWidth,snakeNodeHeight));
    addTopRectF();
    addTopRectF();
    //首先生成一个奖励节点
    rewardNode.append(QRectF(100,100,snakeNodeWidth,snakeNodeWidth));
 
    timer = new QTimer;
    connect(timer, SIGNAL(timeout()),this,SLOT(timeOut()));
    //timer->start(time);
 
    rewardTimer = new QTimer;
    connect(rewardTimer,SIGNAL(timeout()),this,SLOT(rewardTimeOut()));
    //rewardTimer->start(time*30);
}
 
Widget::~Widget()
{
    delete ui;
}

界面刷新


void Widget::timeOut()
{
    int flage = 1;
    for(int i=0; i<rewardNode.length(); i++){
        if(rewardNode.at(i).contains(snake.at(0).topLeft()+QPointF(snakeNodeWidth/2,snakeNodeHeight/2))){
        //if(snake.at(0).contains(rewardNode.at(i).x()+rewardNode.at(i).width()/2,rewardNode.at(i).y()+rewardNode.at(i).height()/2)){
            if(rewardNode.at(i).width()>snakeNodeWidth){//额外奖励
                flage += 2;
            }
            flage++;//正常奖励
            rewardNode.removeAt(i);
            break;
        }
    }
    while(flage--){
        switch (moveFlage) {
        case Up:
            addTopRectF();
            break;
        case Down:
            addDownRectF();
            break;
        case Right:
            addRightRectF();
            break;
        case Left:
            addLeftRectF();
            break;
        default:
            break;
        }
    }
    deleteLastRectF();
 
    update();
}

随机奖励的生成


//随机奖励
void Widget::rewardTimeOut()
{
    qsrand(QTime(0,0,0).secsTo(QTime::currentTime()));
    if(rewardNode.length() > 5){
        rewardNode.removeAt(qrand()%5);
    }
    rewardNode.append(QRectF(qrand()%(this->width()/20)*20,qrand()%(this->height()/20)*20,snakeNodeWidth,snakeNodeWidth));
    if(qrand()%5 == 3){
        rewardNode.append(QRectF(qrand()%(this->width()/20)*20-5,qrand()%(this->height()/20)*20-5,snakeNodeWidth*2,snakeNodeWidth*2));
    }
}

移动


//向上移动
void Widget::addTopRectF()
{
    if(snake.at(0).y()-snakeNodeHeight < 0){
        snake.insert(0,QRectF(QPointF(snake.at(0).x(),this->height()-snakeNodeHeight),
                              QPointF(snake.at(0).x()+snakeNodeWidth,this->height())));
    }else{
        snake.insert(0,QRectF(snake.at(0).topLeft()+QPointF(0,-snakeNodeHeight),snake.at(0).topRight()));
    }
}
//向下移动
void Widget::addDownRectF()
{
    if(snake.at(0).y()+snakeNodeHeight*2 > this->height()){
        snake.insert(0,QRectF(QPointF(snake.at(0).x(),snakeNodeHeight),
                              QPointF(snake.at(0).x()+snakeNodeWidth,0)));
    }else{
        snake.insert(0,QRectF(snake.at(0).bottomLeft(),snake.at(0).bottomRight()+QPointF(0,snakeNodeHeight)));
    }
}
//向左移动
void Widget::addLeftRectF()
{
    if(snake.at(0).x()-snakeNodeWidth < 0){
        snake.insert(0,QRectF(QPointF(this->width()-snakeNodeWidth,snake.at(0).y()),
                              QPointF(this->width(),snake.at(0).y()+snakeNodeHeight)));
    }else{
        snake.insert(0,QRectF(snake.at(0).topLeft()+QPointF(-snakeNodeWidth,0),snake.at(0).bottomLeft()));
    }
}
//向右移动
void Widget::addRightRectF()
{
    if(snake.at(0).x()+snakeNodeWidth*2 > this->width()){
        snake.insert(0,QRectF(QPointF(0,snake.at(0).y()),
                              QPointF(snakeNodeWidth,snake.at(0).y()+snakeNodeHeight)));
    }else{
        snake.insert(0,QRectF(snake.at(0).topRight(),snake.at(0).bottomRight()+QPointF(snakeNodeWidth,0)));
    }
}
//删除结尾数据
void Widget::deleteLastRectF()
{
    snake.removeLast();
}

绘图


//绘图
void Widget::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    QPen pen;
    QBrush brush;
    QFont font("方正舒体",12,QFont::ExtraLight,false);
 
    //反锯齿
    painter.setRenderHint(QPainter::Antialiasing);
 
    pen.setColor(Qt::black);
    brush.setColor(Qt::green);
    brush.setStyle(Qt::SolidPattern);
    painter.setPen(pen);
    painter.setBrush(brush);
 
    for(int i=0; i<snake.length(); i++){
        painter.drawRect(snake.at(i));
    }
    brush.setColor(Qt::red);
    painter.setBrush(brush);
    for(int i=0; i<rewardNode.length(); i++){
        painter.drawEllipse(rewardNode.at(i));
    }
    pen.setColor(Qt::white);
    painter.setPen(pen);
    painter.setFont(font);
    painter.drawText(20,20,QString("当前得分：")+QString("%1").arg(snake.length()));
 
    if(snakeStrike()){
        QFont font("方正舒体",30,QFont::ExtraLight,false);
        painter.setFont(font);
        painter.drawText((this->width()-300)/2,(this->height()-30)/2,QString("GAME OVER!"));
        timer->stop();
        rewardTimer->stop();
        gameOver = true;
    }
 
    QWidget::paintEvent(event);
}

按键事件


void Widget::keyPressEvent(QKeyEvent *event)
{
    switch(event->key()){
    case Qt::Key_Up:
        if(moveFlage != Down){
            moveFlage = Up;
        }
        break;
    case Qt::Key_Down:
        if(moveFlage != Up){
            moveFlage = Down;
        }
        break;
    case Qt::Key_Right:
        if(moveFlage != Left){
            moveFlage = Right;
        }
        break;
    case Qt::Key_Left:
        if(moveFlage != Right){
            moveFlage = Left;
        }
        break;
    case Qt::Key_Enter:
    case Qt::Key_Return:
        if(gameOver){
            snake.clear();
            rewardNode.clear();
            moveFlage = Up;
            snake.append(QRectF(200,500,snakeNodeWidth,snakeNodeHeight));
            addTopRectF();
            addTopRectF();
            //首先生成一个奖励节点
            rewardNode.append(QRectF(100,100,snakeNodeWidth,snakeNodeWidth));
            timer->start(time);
            rewardTimer->start(time*30);
            gameOver = false;
        }
        break;
    case Qt::Key_Space:
        if(gameStart && !gameOver){
            timer->start(time);
            rewardTimer->start(time*30);
            gameStart = false;
        }else if(!gameStart && !gameOver){
            timer->stop();
            rewardTimer->stop();
            gameStart = true;
        }
        break;
    default:
        break;
    }
}

判断蛇身是否相撞


//判断蛇头是否和蛇身相撞
bool Widget::snakeStrike()
{
    for(int i=0; i<snake.length(); i++){
        for(int j=i+1; j<snake.length(); j++){
            if(snake.at(i) == snake.at(j)){
                return true;
            }
        }
    }
    return false;
 
}