基本动作和组合动作实现了针对精灵的各种运动和动画效果的改变。但这样的改变速度匀速的、线性的。通过ActionEase及其的派生类和Speed 类我们可以使精灵以非匀速或非线性速度运动这样看起了效果更加逼真。
ActionEase的类图如下图所示。
下面我们通过一个实例介绍一下这些动作中速度的控制的使用这个实例如下图所示上图是一个操作菜单场景选择菜单可以进入到下图动作场景在下图动作场景中点击Go按钮可以执行我们选择的动作效果点击Back按钮可以返回到菜单场景。
下面我们再看看具体的程序代码首先看一下看HelloWorldScene.h文件它的代码如下
#ifndef __HELLOWORLD_SCENE_H__
#define __HELLOWORLD_SCENE_H__
#include "cocos2d.h"
#include "MyActionScene.h"
typedef enum ①
{
kEaseIn = 1
,kEaseOut
,kEaseInOut
,kEaseSineIn
,kEaseSineOut
,kEaseSineInOut
,kEaseExponentialIn
,kEaseExponentialOut
,kEaseExponentialInOut
,kSpeed
} ActionTypes; ②
class HelloWorld : public cocos2d::Layer
{
public:
static cocos2d::Scene* createScene();
virtual bool init();
void OnClickMenu(cocos2d::Ref* pSender);
CREATE_FUNC(HelloWorld);
};
#endif // __HELLOWORLD_SCENE_H__
上述代码第①~②是定义个枚举类型ActionTypes枚举类型ActionTypes中定义了10个常量这10个常量对应10个菜单项。
HelloWorldScene的实现代码HelloWorldScene.ccp文件它的主要代码如下
bool HelloWorld::init()
{
if( !Layer::init() )
{
returnfalse;
}
SizevisibleSize = Director::getInstance()->getVisibleSize();
Pointorigin = Director::getInstance()->getVisibleOrigin();
autobg = Sprite::create("background.png");
bg->setPosition(Point(visibleSize.width/2,visibleSize.height /2));
this->addChild(bg);
autopItmLabel1 = Label::createWithBMFont("fonts/fnt2.fnt","EaseIn");
autopItmMenu1 = MenuItemLabel::create(pItmLabel1,
CC_CALLBACK_1(HelloWorld::OnClickMenu, this));
pItmMenu1->setTag(kEaseIn);
autopItmLabel2 = Label::createWithBMFont("fonts/fnt2.fnt","EaseOut");
autopItmMenu2 = MenuItemLabel::create(pItmLabel2,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu2->setTag(kEaseOut);
autopItmLabel3 = Label::createWithBMFont("fonts/fnt2.fnt","EaseInOut");
autopItmMenu3 = MenuItemLabel::create(pItmLabel3,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu3->setTag(kEaseInOut);
autopItmLabel4 = Label::createWithBMFont("fonts/fnt2.fnt","EaseSineIn");
autopItmMenu4 = MenuItemLabel::create(pItmLabel4,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu4->setTag(kEaseSineIn);
autopItmLabel5 = Label::createWithBMFont("fonts/fnt2.fnt", "EaseSineOut");
autopItmMenu5 = MenuItemLabel::create(pItmLabel5,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu5->setTag(kEaseSineOut);
autopItmLabel6 = Label::createWithBMFont("fonts/fnt2.fnt","EaseSineInOut");
autopItmMenu6 = MenuItemSprite::create(pItmLabel6,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu6->setTag(kEaseSineInOut);
autopItmLabel7 = Label::createWithBMFont("fonts/fnt2.fnt","EaseExponentialIn");
autopItmMenu7 = MenuItemSprite::create(pItmLabel7,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu7->setTag(kEaseExponentialIn);
autopItmLabel8 = Label::createWithBMFont("fonts/fnt2.fnt","EaseExponentialOut");
autopItmMenu8 = MenuItemLabel::create(pItmLabel8,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu8->setTag(kEaseExponentialOut);
autopItmLabel9 = Label::createWithBMFont("fonts/fnt2.fnt","EaseExponentialInOut");
autopItmMenu9 = MenuItemLabel::create(pItmLabel9,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu9->setTag(kEaseExponentialInOut);
autopItmLabel10 = Label::createWithBMFont("fonts/fnt2.fnt","Speed");
autopItmMenu10 = MenuItemLabel::create(pItmLabel10,
CC_CALLBACK_1(HelloWorld::OnClickMenu,this));
pItmMenu10->setTag(kSpeed);
automn = Menu::create(pItmMenu1,pItmMenu2,pItmMenu3,pItmMenu4,pItmMenu5,
pItmMenu6,pItmMenu7,pItmMenu8,pItmMenu9,pItmMenu10,NULL);
mn->alignItemsInColumns(2,2, 2, 2, 2, NULL);
this->addChild(mn);
returntrue;
}
void HelloWorld::OnClickMenu(Ref* pSender)
{
MenuItem*nmitem = (MenuItem*)pSender;
auto sc = Scene::create();
auto layer = MyAction::create();
layer->setTag(nmitem->getTag());
sc->addChild(layer);
autoreScene = TransitionSlideInR::create(1.0f, sc);
Director::getInstance()->replaceScene(reScene);
}
在上诉代码大家比较熟悉了我们这里就不再介绍了。下面我们再看看下一个场景MyActionScene它的MyActionScene.ccp它的主要代码如下
void MyAction::goMenu(Ref* pSender)
{
log("Tag = %i",this->getTag());
FiniteTimeAction * ac1 = (FiniteTimeAction *)MoveBy::create(2,Point(200, 0));
FiniteTimeAction * ac2 = ((FiniteTimeAction *)ac1)->reverse();
ActionInterval * ac = Sequence::create(ac1, ac2, NULL);
switch (this->getTag()) {
case kEaseIn:
sprite->runAction(EaseIn::create(ac, 3)); ①
break;
case kEaseOut:
sprite->runAction(EaseOut::create(ac, 3)); ②
break;
case kEaseInOut:
sprite->runAction(EaseInOut::create(ac,3)); ③
break;
case kEaseSineIn:
sprite->runAction(EaseSineIn::create(ac)); ④
break;
case kEaseSineOut:
sprite->runAction(EaseSineOut::create(ac)); ⑤
break;
case kEaseSineInOut:
sprite->runAction(EaseSineInOut::create(ac)); ⑥
break;
case kEaseExponentialIn:
sprite->runAction(EaseExponentialIn::create(ac)); ⑦
break;
case kEaseExponentialOut:
sprite->runAction(EaseExponentialOut::create(ac)); ⑧
break;
case kEaseExponentialInOut:
sprite->runAction(EaseExponentialInOut::create(ac)); ⑨
break;
case kSpeed:
sprite->runAction(Speed::create(ac, (CCRANDOM_0_1() * 5))); ⑩
break;
}
}
第①行代码sprite->runAction(EaseIn::create(ac, 3))是以3倍速度由慢至快。第②代码sprite->runAction(EaseOut::create(ac, 3))是以3倍速度由快至慢。第③代码sprite->runAction(EaseInOut::create(ac, 3))是以3倍速度由慢至快再由快至慢。
第④代码sprite->runAction(EaseSineIn::create(ac))是采用正弦变换速度由慢至快。第⑤代码sprite->runAction(EaseSineOut::create(ac))是采用正弦变换速度由快至慢。第⑥代码sprite->runAction(EaseOut::create(ac, 3)) 是采用正弦变换速度由慢至快再由快至慢。
第⑦代码sprite->runAction(EaseExponentialIn::create(ac))采用指数变换速度由慢至快。第⑧代码sprite->runAction(EaseExponentialOut::create(ac))采用指数变换速度由快至慢。第⑨代码sprite->runAction(EaseExponentialInOut::create(ac)) 采用指数变换速度由慢至快再由快至慢。
第⑩代码sprite->runAction(Speed::create(ac, (CCRANDOM_0_1() * 5))) 随机设置变换速度。
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《Cocos2d-x实战 C++卷》源码及样章下载地址
源码下载地址http://51work6.com/forum.php?mod=viewthread&tid=1155&extra=page%3D1
样章下载地址http://51work6.com/forum.php?mod=viewthread&tid=1157&extra=page%3D1
