[Cocos2Dx-一个都不能死]2.给游戏添加边框

1. C++语言基础
2. 创建物理世界
3. 添加边框

在游戏世界中，任务跳起来后会掉下来，这个涉及到世界的重力加速度，不过我们首先要说一下C++语言的基础！
1.C++作为面向对象语言编程，由头文件.h和源文件.cpp组成，其中头文件负责对象的声明，方法的声明，源文件负责对象的具体实现！
如果要使用类里面的对象，使用.字符，则Class.object
如果要使用类里面的方法，使用->字符，Director::getInstance()->getVisibleSize()
而::是类作用域运算符，看定义

#pragma once
 
 
include 
 
 
include 
 
 
USING_NS_CC;
 class EdgeBox :public Node//创建EdgeBox继承自Node
 {
 public:
 virtual bool init();//声明初始化函数
 CREATE_FUNC(EdgeBox);//创建类
 private://定义私有变量
 };
 

#include "EdgeBox.h"
 //负责EdgeBox的实现
 bool EdgeBox::init() {
 Node::init();//调用Node父类的init方法
 
 
//设置锚点
Size visiableSize = Director::getInstance()->getVisibleSize();
setAnchorPoint(cocos2d::Vec2(0.5,0.5));
setContentSize(visiableSize);
setPhysicsBody(PhysicsBody::createEdgeBox(visiableSize));
//配置边界框
return true;
 
 
}
 

2.创建物理世界
在Cocos2D的代码构成主要由下图组成

Cocos2D

而我们知道Cocos2D项目的入口是从AppDelegate进入的，而里面有三个比较重要的方法

• applicationDidFinishLaunching()
  应用程序启动后调用。默认的实现中已经包含了游戏启动的必要准备。
  因为我们的游戏是竖屏的，所以需要添加屏幕的宽高设置
  

  glview->setDesignResolutionSize(480, 800, ResolutionPolicy::EXACT_FIT);

if (CC_TARGET_PLATFORM == CC_PLATFORM_WIN32) || (CC_TARGET_PLATFORM == CC_PLATFORM_MAC)

glview->setFrameSize(360, 600);

endif

 bool AppDelegate::applicationDidFinishLaunching() {
 // initialize director
 auto director = Director::getInstance();
 auto glview = director->getOpenGLView();
 if(!glview) {
 -#if (CC_TARGET_PLATFORM == CC_PLATFORM_WIN32) || (CC_TARGET_PLATFORM == CC_PLATFORM_MAC) || (CC_TARGET_PLATFORM == CC_PLATFORM_LINUX)
 glview = GLViewImpl::createWithRect("noonedies", cocos2d::Rect(0, 0, designResolutionSize.width, designResolutionSize.height));
 -#else
 glview = GLViewImpl::create("noonedies");
 -#endif
 director->setOpenGLView(glview);
 }
 glview->setDesignResolutionSize(480, 800, ResolutionPolicy::EXACT_FIT);
 -#if (CC_TARGET_PLATFORM == CC_PLATFORM_WIN32) || (CC_TARGET_PLATFORM == CC_PLATFORM_MAC)
 glview->setFrameSize(360, 600);
 
 
endif
 
 
// turn on display FPS
director->setDisplayStats(true);

// set FPS. the default value is 1.0/60 if you don't call this
director->setAnimationInterval(1.0f / 60); 

// create a scene. it's an autorelease object
auto scene = HelloWorld::createScene();

// run
director->runWithScene(scene);

return true;
 
 
}
 

• applicationDidEnterBackground()
  程序进入后台时调用。接打电话时。暂停音乐和动作.
  

  // This function will be called when the app is inactive. Note, when receiving a phone call it is invoked.
   void AppDelegate::applicationDidEnterBackground() {
   Director::getInstance()->stopAnimation();
   
  // if you use SimpleAudioEngine, it must be paused
   // SimpleAudioEngine::getInstance()->pauseBackgroundMusic();
   }

• applicationDidEnterForeground()
  与applicationDidEnterBG()成对出现，应用程序回到前台时使用。
  

  
   // This function will be called when the app is inactive. Note, when receiving a phone call it is invoked.
   void AppDelegate::applicationDidEnterBackground() {
   Director::getInstance()->stopAnimation();
   
  // if you use SimpleAudioEngine, it must be paused
   // SimpleAudioEngine::getInstance()->pauseBackgroundMusic();
   }
   // this function will be called when the app is active again
   void AppDelegate::applicationWillEnterForeground() {
   Director::getInstance()->startAnimation();
   // if you use SimpleAudioEngine, it must resume here
   // SimpleAudioEngine::getInstance()->resumeBackgroundMusic();
   }

  
  

  auto scene = HelloWorld::createScene();
  director->runWithScene(scene);

  
  这句就是程序的场景入口！

而我们进入了HelloScene场景后，在创建场景的createScene()方法内将Scene::create()改为 Scene::createWithPhysics()，则创建了物理世界
scene->getPhysicsWorld()->setGravity(Vec2(0, -1000));
设置了重力加速度是1000
之后我们要设置边界框！！

3.添加边界框场景
首先声明一个C++头文件，命名为EdgeBox，继承于Node
在头文件里面，新建一个类EdgeBox，声明初始化方法并调用CREATE_FUNC(EdgeBox)创建

#pragma once
 #include #include 
 USING_NS_CC;
 class EdgeBox :public Node
 {
 public:
 virtual bool init();
 CREATE_FUNC(EdgeBox);
 };
 

而设置边界框，需要先获取屏幕的宽高，并在物理世界配置的边界框

 
 
include "EdgeBox.h"
 
 
bool EdgeBox::init() {
 Node::init();
 Size visiableSize = Director::getInstance()->getVisibleSize();//获取屏幕宽高
 setAnchorPoint(cocos2d::Vec2(0.5,0.5)); //设置锚点
 setContentSize(visiableSize); //设置内容宽高
 setPhysicsBody(PhysicsBody::createEdgeBox(visiableSize));//配置边界框
 return true;
 }
 

最后将边界框添加到HelloWorld场景中

 auto edge = EdgeBox::create();
 edge->setContentSize(visiableSize);
 edge->setPosition(visiableSize.width / 2, visiableSize.height / 2+ positionY);
 edge->setContentSize(visiableSize);
 addChild(edge);
 

大功告成！

项目git地址：https://github.com/marco115/NoOneDies.git
对文章有什么优化改进的地方，请留言！谢谢大家