Cocos2d-x3.2 绘制线条

#include "cocos2d.h"
USING_NS_CC;

class  GameScene :  public  Layer
{
public :
    static  Scene* createScene();

    virtual  bool  init();

    void  menuCallback(Ref* pSender);

    CREATE_FUNC(GameScene);

    //重载draw方法
    virtual  void  draw(Renderer *renderer,  const  Mat4 &transform, uint32_t flags) override;

protected :
    //自定义draw实现
    void  onDraw( const  cocos2d::Mat4 &transform,  bool  transformUpdated);
    cocos2d::CustomCommand _customCommand;

private :         //注意不能用auto关键字
    Size size;
    Sprite *sprite;
};

#include "GameScene.h"

USING_NS_CC;

cocos2d::Scene* GameScene::createScene()
{
    auto  scene = Scene::create();    //创建一个场景
    auto  layer = GameScene::create();    //创建一个图层
    scene->addChild(layer);
    return  scene;
}

//初始化当前的图层
bool  GameScene::init()
{
    if (!Layer::init())       //初始化父类
        return  false ;

    //获取屏幕大小
    size = Director::getInstance()->getVisibleSize();
    //auto size = Director::getInstance()->getWinSize();


    return  true ;
}

void  GameScene::draw(Renderer *renderer,  const  Mat4 &transform, uint32_t flags)
{
    _customCommand.init(_globalZOrder);
    _customCommand.func = CC_CALLBACK_0(GameScene::onDraw,  this , transform, flags);
    renderer->addCommand(&_customCommand);
}

void  GameScene::onDraw( const  cocos2d::Mat4 &transform,  bool  transformUpdated)
{
    //利用Stack缓存
    Director *director = Director::getInstance();
    //CCASSERT(nullptr != director, "Director is null when setting matrix stack");
    director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, transform);

    CHECK_GL_ERROR_DEBUG();

    //画边框
    DrawPrimitives::setDrawColor4B(255, 255, 255, 255);
    glLineWidth(10);
    Vec2 vertices[] = {Vec2(100, 100), Vec2(300, 100), Vec2(300, 300), Vec2(100, 300)};
    DrawPrimitives::drawPoly(vertices, 4,  true );

    CHECK_GL_ERROR_DEBUG();

    //绘制停止，释放
    director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
}

void  GameScene::menuCallback(Ref* pSender)
{

}