How to make game using Qt - Lesson 5. Adding sound QMediaPlayer

написать игру, GameDev, QMediaPlayer, QMediaPlaylist, Qt, Qt звук

Getting to the fifth and final lesson on writing games on Qt, which will add sound using QMediaPlayer class. I propose to add the three types of sounds: Eating apples, buzzing flies that will be buzzing when moving and heartbreaking cry when Fly will eaten.

The sound in the project structure

The sound in the project structure is placed in a resource file, as shown in the screenshot of the project structure.

To do this, create a resource directory and folder game . Further, in the resources folder, create a resource file, which prescribes the prefix "/" and add audio files that are pre-placed in the game folder.

And then the sound must be connected to the project using QMediaPlayer class.

In this case, the sounds are connected in three places of the code.

triangle.h

In the header file, you must connect the class library and QMediaPlayer QMediaPlaylist. And also announce at the object of these classes.

#ifndef TRIANGLE_H
#define TRIANGLE_H

#include <QObject>
#include <QGraphicsItem>
#include <QPainter>
#include <QGraphicsScene>
#include <QMediaPlayer>
#include <QMediaPlaylist>

#include <windows.h>

class Triangle : public QObject, public QGraphicsItem
{
    Q_OBJECT
public:
    explicit Triangle(QObject *parent = 0);
    ~Triangle();

    // The code from the previous lessons

    QMediaPlayer * m_player;        // Audio player
    QMediaPlaylist * m_playlist;    // Playlist

};

#endif // TRIANGLE_H

triangle.cpp

Initialization QMediaPlayer object is made in the constructor of the class, but the management of audio playback will be realized in the slot game Fly as fly should buzz only when the game moves on stage.

#include "triangle.h"

Triangle::Triangle(QObject *parent) :
    QObject(parent), QGraphicsItem()
{
    angle = 0;     
    steps = 1;      
    countForSteps = 0;     
    setRotation(angle);    

    m_player = new QMediaPlayer(this);          // Init player
    m_playlist = new QMediaPlaylist(m_player);  // Init playlist

    m_player->setPlaylist(m_playlist);          // Set playlist into player
    m_playlist->addMedia(QUrl("qrc:/game/bzzz.wav"));       // Adding of track to playlist
    m_playlist->setPlaybackMode(QMediaPlaylist::CurrentItemInLoop); // track loop
}

Triangle::~Triangle()
{

}

QRectF Triangle::boundingRect() const
{
    return QRectF(-40,-50,80,100);   
}

void Triangle::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
   // The code from the previous lessons
}

void Triangle::slotGameTimer()
{
    if(GetAsyncKeyState(VK_LEFT) ||
       GetAsyncKeyState(VK_RIGHT) ||
       GetAsyncKeyState(VK_UP) ||
       GetAsyncKeyState(VK_DOWN))
    {
       // The code from the previous lessons

        m_player->play();   // The player plays only when the fly moves
    } else {
        m_player->stop();   
    }

    // The code from the previous lessons
}

widget.h

The class header file, which acts as the core of the game, you only need to connect the library, which are responsible for classes and QMediaPlayer QMediaPlaylist.

widget.cpp

In this class, there is no global ad QMediaPlayer object because objects are created dynamically, for example, for every apple eaten. Due to the fact that apples can be eaten very quickly and almost simultaneously, and the sounds of eating apples will sound together, one player can not cope with such a task, so you have to run on the player at every sound. Also individual player will play death of Fly.

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    // The code from the previous lessons
}

Widget::~Widget()
{
    delete ui;
}

void Widget::slotDeleteApple(QGraphicsItem *item)
{
    foreach (QGraphicsItem *apple, apples) {
        if(apple == item){
            scene->removeItem(apple);   
            apples.removeOne(apple);    
            delete apple;               
            ui->lcdNumber->display(count++);    

            // The sound eating apple
            QMediaPlayer * m_player = new QMediaPlayer(this);   // Initialize player
            QMediaPlaylist * m_playlist = new QMediaPlaylist(m_player); // create a playlist

            m_player->setPlaylist(m_playlist);  // set playlist to player
            m_playlist->addMedia(QUrl("qrc:/game/hrum.wav")); // Add audio to player
            m_playlist->setPlaybackMode(QMediaPlaylist::CurrentItemOnce); // play one time
            m_player->play();   // run player
        }
    }
}

void Widget::slotCreateApple()
{
   // The code from the previous lessons
}

void Widget::on_pushButton_clicked()
{
   // The code from the previous lessons

    ui->pushButton->setEnabled(false);

    gameState = GAME_STARTED;
}

void Widget::slotGameOver()
{
    timer->stop();
    timerCreateApple->stop();

    // If Fly was Killed, then run death cry
    QMediaPlayer * m_player = new QMediaPlayer(this);       
    QMediaPlaylist * m_playlist = new QMediaPlaylist(m_player); 

    m_player->setPlaylist(m_playlist);      
    m_playlist->addMedia(QUrl("qrc:/game/scream.wav")); 
    m_playlist->setPlaybackMode(QMediaPlaylist::CurrentItemOnce);   
    m_player->play();   

    // The code from the previous lessons
}

void Widget::slotPause()
{
    // The code from the previous lessons
}

Result

That's finished work on our first game. Now you have an idea of how to create a simple game on the Qt C ++.

Full source code: Source

Game: Muha_Setup

A full list of articles in this series:

• Lesson 1. How to make game using Qt. Control of object
• Lesson 2. How to make game using Qt. Animation game hero (2D)
• Lesson 3. How to make game using Qt. Interaction with other objects
• Lesson 4. How to make game using Qt. Enemy – meaning in the survival
• Lesson 5. How to make game using Qt. Adding sound QMediaPlayer

Video