cocos2dx实现刮奖效果

local winsize = cc.Director:sharedDirector():getWinSize(); local dataSprite = cc.Sprite:create("Star.png")--要把这个图片刮出来 dataSprite:setAnchorPoint(cc.p(0.5, 0.5)); dataSprite:move(winsize.width / 2.0, winsize.height / 2.0); self:addChild(dataSprite)  pEarse = cc.DrawNode:create() pEarse:drawDot(cc.p(0, 0), 5, cc.c4f(1, 0, 0, 1)); pEarse:retain()  pRTex = cc.RenderTexture:create(winsize.width, winsize.height); pRTex:setPosition(cc.p(winsize.width / 2, winsize.height / 2)); --this:addChild(pRTex); pRTex:retain()  local pBg = cc.Sprite:create("d1.png");--这个作为当“油漆层” pBg:setAnchorPoint(cc.p(0.5, 0.5)); pBg:move(winsize.width / 2.0, winsize.height / 2.0);  pRTex:begin(); dataSprite:visit(); pBg:visit(); pRTex:endToLua(); local layer=cc.Layer:create() self:addChild(layer, 1000) layer:addChild(pRTex); layer:setNodeTouch(handler(self, self.onTouchStart)) 

function shop.erasure(event)  -- body  print("erasure: ", event.name)  --todo  print("moved")  local touchPoint = event.pos  pEarse:setPosition(event.pos.x, event.pos.y);  -- 设置混合模式  local blendFunc = { GL_ONE, GL_ZERO };  pEarse:setBlendFunc(blendFunc);  -- 将橡皮擦的像素渲染到画布上，与原来的像素进行混合  pRTex:begin();  pEarse:visit();  pRTex:endToLua();   end 

void function(){  //test code   auto aPanelSprite = Sprite::create("potentiometerTrack.png");   aPanelSprite->setPosition(Vec2(s.width / 2, s.height / 2));   this->addChild(aPanelSprite);    pEase = DrawNode::create();   pEase->retain();   pEase->drawDot(Point(0, 0), 4.0f, Color4F(255, 0, 0, 255));    pRender = RenderTexture::create(s.width, s.height);   pRender->retain();   pRender->setPosition(Vec2(s.width / 2, s.height / 2));   this->addChild(pRender); //渲染纹理层需加入该父节点层    auto pBg = Sprite::create("potentiometerProgress.png"); //这个作为当“油漆层”  pBg->setAnchorPoint(Point(0.5, 0.5));  pBg->setPosition(Vec2(s.width / 2, s.height / 2));   pRender->begin();  aPanelSprite->visit();  pBg->visit();  pRender->end();   auto listener = EventListenerTouchOneByOne::create();  listener->setSwallowTouches(true);   listener->onTouchBegan = CC_CALLBACK_2(SpriteEaseBezier::onTouchBegan, this);  listener->onTouchMoved = CC_CALLBACK_2(SpriteEaseBezier::onTouchMoved, this);   auto _eventDispatcher = CCDirector::getInstance()->getEventDispatcher();  _eventDispatcher->addEventListenerWithFixedPriority(listener, -10); }  bool SpriteEaseBezier::onTouchBegan(Touch *touch, Event *unused_event) {  CCLOG("SpriteEaseBezier::onTouchBegan");  return true; }  void SpriteEaseBezier::onTouchMoved(Touch *touch, Event *unused_event) {  auto touchPoint = touch->getLocation();  pEase->setPosition(touchPoint.x, touchPoint.y);   BlendFunc blendFunc = { GL_ONE, GL_ZERO };  pEase->setBlendFunc(blendFunc);   pRender->begin();  pEase->visit();  pRender->end();  CCLOG("SpriteEaseBezier::onTouchMoved"); }