Little snippet of how to create sandwich scene with 2D-3D-2D layers in cocos2d-x

test3dscene.cpp

#include "Test3dScene.h"
#include "2d/CCActionInterval.h"
#include "2d/CCCamera.h"
#include "2d/CCSprite.h"
#include "3d/CCAnimate3D.h"
#include "3d/CCAnimation3D.h"
#include "3d/CCSprite3D.h"
#include "base/CCDirector.h"
#include "base/ccTypes.h"
#include "math/CCGeometry.h"
#include "math/Vec2.h"
#include "math/Vec3.h"
#include <vector>

using namespace cocos2d;

bool Test3dScene::init()
{
    if (!cocos2d::Scene::init())
        return false;

    m_3d = Node::create();
    m_front = Node::create();
    m_background = Node::create();

    auto visibleSize = Director::getInstance()->getVisibleSize();

    m_cameras.resize(3);

    Camera* ca = nullptr;

    ca = m_cameras[CAMERA_BG] = Camera::create();
    ca->setDepth(CAMERA_BG);
    ca->setCameraFlag(CameraFlag::USER1);
    m_background->addChild(ca);

    auto backgroundSprite = cocos2d::Sprite::create("3d/texture.png");
    backgroundSprite->setColor(cocos2d::Color3B(0, 255, 0));
    backgroundSprite->setPosition(cocos2d::Vec2(150, 150));
    backgroundSprite->setCameraMask((unsigned short)CameraFlag::USER1, true);
    m_background->addChild(backgroundSprite);

    addChild(m_background);

    ca = m_cameras[CAMERA_3D] =
        Camera::create();
    ca->setDepth(CAMERA_3D);
    ca->setCameraFlag(CameraFlag::USER2);
    m_3d->addChild(ca);
    auto copter = createCopter();
    copter->setCameraMask((unsigned short)CameraFlag::USER2, true);
    m_3d->addChild(copter);
    addChild(m_3d);

    ca = m_cameras[CAMERA_FG] = this->getDefaultCamera();
    ca->setDepth(CAMERA_FG);

    auto frontSprite = cocos2d::Sprite::create("3d/texture.png");
    frontSprite->setColor(cocos2d::Color3B(255, 0, 0));
    frontSprite->setPosition(cocos2d::Vec2(180, 180));
    frontSprite->setCameraMask((unsigned short)CameraFlag::DEFAULT, true);
    m_front->addChild(frontSprite);
    addChild(m_front);

    return true;
}

Sprite3D* Test3dScene::createCopter()
{
    auto copter = cocos2d::Sprite3D::create("3d/copter_test_01.c3b");
    auto w = cocos2d::Director::getInstance()->getWinSize();
    copter->setPosition(200, 200);
    copter->setTexture("3d/texture.png");
    copter->setScale(0.75f);
    copter->setRotation3D(cocos2d::Vec3(-30,180,30));
    auto animation = cocos2d::Animation3D::create("3d/copter_test_01.c3b");
    auto animate = cocos2d::Animate3D::create(animation);
    float speed = 1.0f;
    animate->setSpeed(speed);
    copter->runAction(cocos2d::RepeatForever::create(animate));
    return copter;
}

test3dscene.h

#ifndef CLASSES_TEST3DSCENE_H_
#define CLASSES_TEST3DSCENE_H_

#include "2d/CCScene.h"
#include "platform/CCPlatformMacros.h"
#include <vector>

namespace cocos2d
{
    class Sprite3D;
}

class Test3dScene : public cocos2d::Scene
{
    public:
        CREATE_FUNC(Test3dScene);
        bool init() override;
    private:
        cocos2d::Sprite3D* createCopter();

        enum { CAMERA_BG = 0, CAMERA_3D, CAMERA_FG };
        cocos2d::Node* m_background;
        cocos2d::Node* m_3d;
        cocos2d::Node* m_front;
        std::vector<cocos2d::Camera*> m_cameras;
};

#endif