cocos2dx+lua实现橡皮擦功能

--橡皮擦功能测试
local function initInfo()
 local scene = CCScene:create()
 
 local layer = CCLayer:create()
 scene:addChild(layer)
 --擦除后要显示的图片
 local tupian = CCSprite:create(ROOT_RES .. "set/tip.png")
 tupian:setPosition(ccp(WinSizeWidth / 2, WinSizeHeight / 2))
 layer:addChild(tupian)
 --涂层
 local tu = CCSprite:create(ROOT_RES..'set/user/BG.png')
 tu:setPosition(ccp(WinSizeWidth/2,WinSizeHeight/2))
 --layer:addChild(tu)
 --将图层遍历到texture,再将texture加入当前层
 local ptex = CCRenderTexture:create(1280,720)
 ptex:setPosition(ccp(WinSizeWidth/2,WinSizeHeight/2))
 layer:addChild(ptex)
 ptex:begin()
 tu:visit()
 ptex:endToLua()
 --橡皮擦CCDrawNode
 --point = CCDrawNode:create()
 --point:drawDot(ccp(0,0),10,ccc4f(0,0,0,0))
 local point = CCSprite:create(ROOT_RES..'set/labBtn.png')
 layer:addChild(point)
 --[[local blend = ccBlendFunc()
 blend.src = 0
 blend.dst = 1
 tu:setBlendFunc(blend)--]]
 --local blend = tu:getBlendFunc()
 layer:registerScriptTouchHandler(function (eventType,x,y)
 if eventType == "began" then
  cclog("began")
  return true
 elseif eventType == "moved" then
  cclog("move")
  point:setPosition(x,y)
  local blend = ccBlendFunc()
  blend.src = 1
  blend.dst = 0
  point:setBlendFunc(blend)
  ptex:begin()
  point:visit()
  ptex:endToLua()
 elseif eventType == "ended" then
  cclog("end")
 elseif eventType == "cancelled" then
  
 end
 end,false,-1000,true)
 layer:setTouchEnabled(true)
 return scene
end

function getInfoLayer()
 CCDirector:sharedDirector():replaceScene(initInfo())
end