【cocos2d-x IOS游戏开发-捕鱼达人16】炮弹攻击效果2

尊重开发者的劳动成果，转载的时候请务必注明出处：http://blog.csdn.net/haomengzhu/article/details/17151883

上节回顾

【cocos2d-x IOS游戏开发-捕鱼达人15】炮弹攻击效果1

1、  炮弹的移动

炮弹规则
玩家点击屏幕后，将从大炮位置向点击位置发射一枚炮弹。

炮弹的移动所需的值
炮弹速度
炮弹发射点
炮弹发射方向
炮弹射程

不同等级的差异
不同等级的炮弹速度不一样（等级越高，速度越慢）
不同等级的炮弹射程不一样（等级越高，射程越大）

炮弹速度相关的计算
根据速度方向，计算出炮弹的水平增量(cos)和竖直增量(sin)

2、  炮弹的爆炸效果

爆炸的时机
达到最大射程
与鱼产生碰撞

爆炸的效果
在爆炸点产生一个网。一定时间后消失

实现触屏相应：

			virtual bool ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent)
			{
				//CC_UNUSED_PARAM(pTouch); 
				//CC_UNUSED_PARAM(pEvent);
				cocos2d::CCPoint pt = pTouch->getLocationInView();
				pt = cocos2d::CCDirector::sharedDirector()->convertToGL(pt);

				cocos2d::CCPoint cannonPt = getPosition();

				float dx = pt.x - cannonPt.x;
				float dy = pt.y - cannonPt.y;
				float t = dx/dy;

				float at = atan(t);
				float degree = at/3.1415926*180;
				//旋转炮台
				m_pCannon->setRotation(degree);

				//相应触屏事件处理
				Event_TapScreen(cannonPt,degree);

				//printf("touch %f,%f\n",pTouch->locationInView().x,pTouch->locationInView().y);
				return false;
			}

添加触屏游戏逻辑：

				base::Delegate<void(const CCPoint&,float)> tes(this,&CPlayUILogic::slot_TapScreen);
				m_CannonLayout.Event_TapScreen += tes;

触屏响应：

			void slot_TapScreen(const CCPoint& pt,float dir)
			{
				printf("pt:(%f,%f),dir:%f \n",pt.x,pt.y,dir);
				m_pGameLogic->onShoot(pt.x,pt.y,dir);
			}

射出炮弹：

		void CGameLogic::onShoot(float x,float y,float dir )
		{
			scene::ISceneObject* pS = m_pGameScene->createObject(1005);
			CBulletObject* pObj = new CBulletObject(pS,this,m_iLevel);
			pObj->setPosition(x,y);
			pObj->setDuration(dir);
			m_vecBulletsList.push_back(pObj);
		}

炮弹状态改变：

class CBulletObject
		{
			enum{
				EXPLODE_TIME = 1,
			};
			scene::ISceneObject* m_pSceneObject;
			EBulletObjectState m_eButtletObjectState;
			IGameLogic* m_pGameLogic;
			float m_OrgX;
			float m_OrgY;
			float m_CurrentX;
			float m_CurrentY;
			float m_Dir;
			float m_Time;
			bool m_bNeedDestroyed;

			float m_Speed;
			float m_Distance;
		public:
			CBulletObject(scene::ISceneObject* pObj,IGameLogic* pLogic,int level)
				:m_pSceneObject(pObj)
				,m_pGameLogic(pLogic)
				,m_eButtletObjectState(EBOS_NORMAL)
				,m_Time(0)
				,m_bNeedDestroyed(false)
			{
				const config::SBulletData* pData = config::CBulletConfig::getData(level);
				if(pData==NULL){
					m_Speed = 0;
					m_Distance = 0;
				}
				else{
					m_Speed = pData->Speed;
					m_Distance = pData->Distance;
				}
				char buf[32];
				sprintf(buf,"bullet%d",level);
				pObj->setAnimation(buf);
			}
			scene::ISceneObject* getSceneObj(){ return m_pSceneObject;}

			bool needDestroyed(){ return m_bNeedDestroyed; }
			void setPosition(float x,float y)
			{
				m_OrgX = x;
				m_OrgY = y;
				m_CurrentX = x;
				m_CurrentY = y;
				m_pSceneObject->setPosition(x,y);
			}

			void setDuration(int degree)
			{
				m_Dir = degree;
				m_pSceneObject->setDuration(degree);
			}
			void update(float dt)
			{
				m_Time+=dt;
				switch(m_eButtletObjectState)
				{
				case EBOS_NORMAL:
					updateNormal(dt);
					break;
				case EBOS_EXPLODE:
					if(m_Time > EXPLODE_TIME){
						m_bNeedDestroyed = true;
					}
					break;
				}
			}

		private:
			void updateNormal(float dt)
			{
				float angle = (90-m_Dir)/180*3.1416926;
				float s = sin(angle);
				float c = cos(angle);
				float dtx = m_Speed*c*dt;
				float dty = m_Speed*s*dt;
				m_CurrentX += dtx;
				m_CurrentY += dty;
				m_pSceneObject->setPosition(m_CurrentX,m_CurrentY);

				dtx = m_CurrentX - m_OrgX;
				dty = m_CurrentY - m_OrgY;
				if(dtx*dtx+dty*dty > m_Distance*m_Distance){
					m_Time = 0;
					m_eButtletObjectState = EBOS_EXPLODE;
					m_pSceneObject->setAnimation("net");
				}
			}
		};

可以看到效果图：

下节实现炮弹与鱼的碰撞检测