Getting Physical – Box2D - Cocos2d-x by Example Beginner's Guide - page 272

director->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
_customCommand.init(_globalZOrder);
_customCommand.func =
CC_CALLBACK_0(GameLayer::onDraw, this);
renderer->addCommand(&_customCommand);
director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
}
void GameLayer::onDraw()
{
auto director = Director::getInstance();
Mat4 oldMV;
oldMV =
director->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW,
_modelViewMV);
_world->DrawDebugData();
director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW,
oldMV);
}