cocos2d-x 3.0 draw() method Question!

cocos2d-x C++
#1

is the cocos2d-x 3.0 call the draw() method in render thread?

i found my gl code in draw() method is working;

but the testcpp all custom draw() code are like this

_renderCommand.init(_globalZOrder);
_renderCommand.func = CC_CALLBACK_0(MySprite::onDraw, this);
Director::getInstance()->getRenderer()->addCommand(&_renderCommand);

then draw something in the onDraw() method

who can tell me whats the diffrents between them thanks!