Cocos 2dx game increasing in memory every time a scene transition occurs

Question

I am making a cocos 2dx game. But each time the memory increases with every level transition. For debugging purposes I am calling the same scene again and again on touch event. Each level is generated by changing the parameters for the folowing code. Initially I thought that the memory was increasing because there were more objects in the higher levels, but even when calling the same level, memory occupied is increasing.

#include "GameScene.h"
#include "MainMenuScene.h"
#include "GameOverScene.h"
#include "Levels.h"
#define COCOS2D_DEBUG 1

USING_NS_CC;

float theta=0;
int r=0;
int levelNo=0;
int controlable=0;      // flag to check if user can controll the ball or not
int rMax=0;             // max radius of circle
float objectTime;     // stores the inverse of speed
int secondCount=0;    // second han value in the timer
int minuteCount=0;   //minute hand clock in the timer
float obstacleSpeed=0;
Label *timer;

GameScene::~GameScene()
{


    rotationPoint->removeAllChildrenWithCleanup(true);
    obstacleRotationPoint->removeAllChildrenWithCleanup(true);
       this->removeAllChildrenWithCleanup(true);

}

Scene* GameScene::createScene(int level)
{
    // 'scene' is an autorelease object
    auto scene = Scene::create();
    controlable=0;
    r=0;
    theta=0;
    // 'layer' is an autorelease object
    levelNo=level;
    rMax=levels[levelNo].ringCount * 15;    //setting various parameters
    obstacleSpeed =levels[levelNo].obstacleSpeed;
    objectTime=1.0/levels[levelNo].speed;
    secondCount=0; minuteCount=0;
    auto layer = GameScene::create();

    // add layer as a child to scene
    scene->addChild(layer);


    // return the scene
    return scene;
}

// on "init" you need to initialize your instance

bool GameScene::init()
{
    //////////////////////////////
    // 1. super init first
    if ( !Layer::init() )
    {
        return false;
    }
    controlable=0;
    distance=rMax;
    visibleSize = Director::getInstance()->getVisibleSize();
    Vec2 origin = Director::getInstance()->getVisibleOrigin();

#if COMPILE_FOR_MOBILE == 1
    auto listener = EventListenerTouchOneByOne::create();
    listener->setSwallowTouches(true);

    listener->onTouchBegan = CC_CALLBACK_2(GameScene::onTouchBegan, this);

    _eventDispatcher->addEventListenerWithSceneGraphPriority(listener, this);

#endif

    goal = DrawNode::create();
    goal->drawDot(Vec2(visibleSize.width/2 + origin.x, visibleSize.height/2 + origin.y), 5, Color4F(100,0,0,1));
    this->addChild(goal,1);          // drawing the goal


    rotationPoint = Node::create();
    rotationPoint->setPosition(visibleSize.width/2 + origin.x, visibleSize.height/2 + origin.y);
    this->addChild(rotationPoint, 2);


    //Setting the exit button
    auto exitLabel = Label::createWithTTF("Exit","fonts/Marker Felt.ttf",10);
    exitButtonWidth=exitLabel->getContentSize().width;
    exitButtonHeight=exitLabel->getContentSize().height;
    exitLabel->setPosition(Point(visibleSize.width-exitButtonWidth,visibleSize.height-exitButtonHeight));
    this->addChild(exitLabel);


    //setting the clock
    timer = Label::createWithTTF("00:00","fonts/Marker Felt.ttf",10);
    timer->setPosition(Point(timer->getContentSize().width,visibleSize.height-timer->getContentSize().height));
    this->schedule(schedule_selector(GameScene::updateClock),1.0f);  //scedule to call upDateClock function every 1.0 sec
    this->addChild(timer);

    obstacleRotationPoint = Node::create();
    obstacleRotationPoint->setPosition(visibleSize.width/2 + origin.x, visibleSize.height/2 + origin.y);
    this->addChild(obstacleRotationPoint, 3);


    float theta=0;

    snake[0] = DrawNode::create();
    snake[0]->drawDot(Vec2(0,0),3,Color4F(100,110,0,1));
    theta+=2*M_PI/150;
    //this->addChild(snake[0],2);

    rotationPoint->addChild(snake[0]);
      // fixedPoint->addChild(snake[0]);


   //loop to draw the concentric circles

   for(r=15;r<=rMax;r+=15)
    {
      for(theta=0;theta<=2*M_PI;theta+=2*M_PI/r){
          pathNode = DrawNode::create();
          pathNode->drawDot(Vec2(r*cos(theta)+origin.x+visibleSize.width/2,r*sin(theta)+origin.y+visibleSize.height/2),1,Color4F(0,0,10,1));
          //pathNode->autorelease();
           this->addChild(pathNode,1);
          //this->removeChild(pathNode);
        }
    }

    controlable=0;
    this->scheduleUpdate();
    return true;
}

bool GameScene::onTouchBegan(cocos2d::Touch *touch, cocos2d::Event *event)
{   // check if exit button region was clicked
    _eventDispatcher->removeAllEventListeners();
    auto scene = GameScene::createScene(levelNo);
    Director::getInstance()->replaceScene(scene);
    return true;
}



//function updates every frame
void GameScene::update(float dt){
}

The last part in the init function where I need to add pathNode is increasing my memory requirement everytime I transition a scene. I believe I am releasing everything in my destructor.

Answer 1

First of all, I don't recommend using global variables, which you have on top of your file (especially timer label). You should keep everything in class.

Second, you should check whether destructor is called in the first place.

Third, you can also try using some "Loading" screen between two levels and clean all unused textures like this:

setOnExitCallback([&](){
    Director::getInstance()->getTextureCache()->removeUnusedTextures();
});

Fourth, I'd recommend to not recreate GameScene at all, but create function like restartLevel() and loadLevel() and just remove unnecessary stuff there and load new one.