Question

I have written code for a game in which some birds are flying. I created array of CCSprite and added them on Scene. Now it assign a scheduler to each bird object for moving in random direction in screen. All are working. Now i am getting trouble in getting collision in birds.

i am trying to run a CCARRAY_FOREACH loop on array but its giving error.

 0xC0000005: Access violation reading location 0xfeeefeee.

Please help me how i can get get collision detection in array element while they are moving. updateCollison method is not executing.

My Code is:

#include "HelloWorldScene.h"

using namespace cocos2d;

CCScene* HelloWorld::scene()
{
    CCScene * scene = NULL;
    do 
    {
        // 'scene' is an autorelease object
        scene = CCScene::create();
        CC_BREAK_IF(! scene);

        // 'layer' is an autorelease object
        HelloWorld *layer = HelloWorld::create();
        CC_BREAK_IF(! layer);

        // add layer as a child to scene
        scene->addChild(layer);
    } while (0);

    // return the scene
    return scene;
}

// on "init" you need to initialize your instance
bool HelloWorld::init()
{
    //srand(time(NULL));
    CCSize size = CCDirector::sharedDirector()->getWinSize();
    birds = CCArray::create();
    for(int j = 0; j<5; j++){
        CCSprite *bird = CCSprite::create("twitter_square.png");
        bird->setTag(j);
        int max = rand() % 480;
        int min = rand() % 320;
        bird->setPosition(ccp(max, min));
        this->addChild(bird);
        birds->addObject(bird);
        bird->schedule( schedule_selector(HelloWorld::moveBird), 5.0 );
bird->schedule( schedule_selector(HelloWorld::updateCollison), 5.0 );
    }

    return true;
}

void HelloWorld::menuCloseCallback(CCObject* pSender)
{
    CCDirector::sharedDirector()->end();
}


void HelloWorld::moveBird(float dt)
{
    CCSize size = CCDirector::sharedDirector()->getWinSize();
    int max = rand() % (int)size.width;
    int min = rand() % (int)size.height;
    CCActionInterval*  actionTo = CCMoveTo::actionWithDuration(5, ccp(max,min));
    this->runAction(actionTo);
}

void HelloWorld::updateCollison(float dt)
{
    CCObject *obj;
    for(int i=0; i < birds->count(); i++)
    {
        CCLOG("$$$$$$$$$$$$$$$$$$$$$$$");
    }
}

Answer 1

It’s better to do things in one update function …for example make one update in that call MoveBird Function which will contain your moving bird code

Secondly now call check Collision function

void update (float dt) {

MoveBird();     // Move how many birds you want to move 
CheckCollision();

}

Now how to check collision of your birds

In your collision function forLoop your birds Array check

if(mBirdsArray[i]->boundingBox().containsPoint(mBirdsArray[j]->getPosition()))

and vice versa …

I hope this will work .. .there maybe better logic than this ..