Cocos2d-x V3 bounded quad particle system is a way of masking particles so the do not exit a given shape and thus creates a masking effect.
Example of use...
std::vector<Point> polyPoints;
polyPoints.push_back(Point(100.0f, 100.0f));
polyPoints.push_back(Point(200.0f, 100.0f));
polyPoints.push_back(Point(200.0f, 200.0f));
polyPoints.push_back(Point(100.0f, 200.0f));
auto particle = BoundedParticleSystemQuad::create("particles/myParticle.plist", polyPoints);
particle->setPosition(Point(150.0f, 100.0f));
this->addChild(particle);