[solved] Moving ParticleSystem moves all particles even with PositionType::Free

cocos2d-x C++
1

Hi,
I have a new HelloWorld project, I just add a ParticleSystem like this :

Scene* HelloWorld::createScene()
{
   // 'scene' is an autorelease object
   auto scene = Scene::create();

   // 'layer' is an autorelease object
   auto layer = HelloWorld::create();

    // add layer as a child to scene
    scene->addChild(layer);
    ParticleSystemQuad* p = ParticleSystemQuad::create("fire.plist");
    p->retain();
    layer->addChild(p);
    p->setTotalParticles(30000);
    p->setPositionType(ParticleSystemQuad::PositionType::FREE);
    p->setLife(20);
    p->setEmissionRate(40);
    p->setTexture( Director::getInstance()->getTextureCache()->addImage("fire.png") );
    p->setScale(0.5f);
    p->resetSystem();
    p->setTag(99);

    // return the scene
    return scene;
}

And I added onTouch event to move the ParticleSystem :

void HelloWorld::onTouchMove(Touch *event, Event *x)
{
    auto pos = Vec2::ZERO;
    pos = convertToWorldSpace(Vec2::ZERO);
    ParticleSystemQuad* p = (ParticleSystemQuad*) getChildByTag(99);
    p->setPosition(event->getLocation() - pos);
}

When I run this simple app, when I move the ParticleSystem, the particles left behind are moving behind even with the Positiontype set to FREE

http://s29.postimg.org/9h0ozb4af/ccp.png

As you see in this example, I started dragging the mouse from the Hello World text to the close button, the particles moved behind and did not kept their original positions.

Thanks for your help

2

Found out the problem, it comes from the setScale(0.5f); line, after commenting it all works as expected. I should use startSize and endSize to reduce the particle’s size instead of using the setScale method.