【学习笔记】Cocos2d-x Lua脚本引擎之HelloLua分析笔记

-- for CCLuaEngine traceback
function __G__TRACKBACK__(msg)
    print("----------------------------------------")
    print("LUA ERROR: " .. tostring(msg) .. "\n")
    print(debug.traceback())
    print("----------------------------------------")
end

local function main()
    -----------------------------------------------------------------
    -- avoid memory leak
    collectgarbage("setpause", 100)
    collectgarbage("setstepmul", 5000)
    --[[-------------------------------------------------------------
    补充说明：
        collectgrabage(opt [, arg])
        功能:垃圾收集器的通用接口，用于操作垃圾收集器
        参数:
            opt--操作方法标志
            "stop" : 停止垃圾收集器
            "restart" : 重启垃圾收集器
            "collect" : 执行一次全垃圾收集循环
            "count" : 返回当前Lua中使用的内存量(以KB为单位)
            "step" : 单步执行一个垃圾收集.步长"size"由参数arg指定.如果完成一次收集循环，将返回True
            "setpause" : 设置arg/100的值作为暂定收集的时长
            "setstepmul" : 设置arg/100的值，作为步长的增幅(即新步长 = 旧步长*(arg/100))
    --]]-------------------------------------------------------------
    
    
    
    
    -----------------------------------------------------------------
    --自定义打印函数，将字符串打印出来
    --其实这里可以调用CCLuaLog函数来打印字符串
    local cclog = function(...)
        print(string.format(...))
    end
    -----------------------------------------------------------------
    
    
    
    

    -----------------------------------------------------------------
    --包含hello2这个脚本，该脚本定义了myadd(x, y)函数
    require "hello2"
    cclog("result is " .. myadd(3, 5))
    -----------------------------------------------------------------
    
    
    
    
    -----------------------------------------------------------------
    --获取可视区域
    local visibleSize = CCDirector:sharedDirector():getVisibleSize()
    --获取可是区域的原点坐标，OpenGL坐标系 左下角为原点
    local origin = CCDirector:sharedDirector():getVisibleOrigin()
    -----------------------------------------------------------------



    -- add the moving dog
    local function creatDog()
        --dog.png的规格是 210*95, 由两个frame组成规格皆为105*95
        local frameWidth = 105
        local frameHeight = 95

        -- create dog animate
        local textureDog = CCTextureCache:sharedTextureCache():addImage("dog.png")
        --rect用于捕捉textureDog的纹理并赋给frame0
        local rect = CCRectMake(0, 0, frameWidth, frameHeight)
        local frame0 = CCSpriteFrame:createWithTexture(textureDog, rect)
        --rect用于捕捉textureDog的纹理并赋给frame1
        rect = CCRectMake(frameWidth, 0, frameWidth, frameHeight)
        local frame1 = CCSpriteFrame:createWithTexture(textureDog, rect)
        
        --创建松鼠精灵
        local spriteDog = CCSprite:createWithSpriteFrame(frame0)
        spriteDog.isPaused = false
        spriteDog:setPosition(origin.x, origin.y + visibleSize.height / 4 * 3)
        
        
        
        --接下来的代码是要创建一个CCAction对象，让spriteDog来run这个CCAction对象
        --步骤如下：
          --1.使用数组animFrames保存序列帧
          --2.利用该数组创建一个CCAnimation对象
          --3.利用CCAnimation对象创建CCAnimate对象
          --4.利用CCAnimate对象创建CCAction对象
          --5.run这个CCAction
        
        local animFrames = CCArray:create()

        animFrames:addObject(frame0)
        animFrames:addObject(frame1)

        local animation = CCAnimation:createWithSpriteFrames(animFrames, 0.5)
        local animate = CCAnimate:create(animation);
        spriteDog:runAction(CCRepeatForever:create(animate))
        -----------------------------------------------------------------




        -- moving dog at every frame
        local function tick()
            --如果暂停了，那么返回，不对spriteDog做任何操作
            if spriteDog.isPaused then return end
            
            --根据spriteDog的当前position来判断下一个position
            local x, y = spriteDog:getPosition()
            if x > origin.x + visibleSize.width then
                x = origin.x
            else
                x = x + 1
            end
            
            --更新位置
            spriteDog:setPositionX(x)
        end
        --设置每帧调用trick函数
        CCDirector:sharedDirector():getScheduler():scheduleScriptFunc(tick, 0, false)

        return spriteDog
    end

    -- create farm
    local function createLayerFarm()
        local layerFarm = CCLayer:create()

        -- add in farm background
        local bg = CCSprite:create("farm.jpg")
        bg:setPosition(origin.x + visibleSize.width / 2 + 80, origin.y + visibleSize.height / 2)
        layerFarm:addChild(bg)

        -- add land sprite
        for i = 0, 3 do
            for j = 0, 1 do
                local spriteLand = CCSprite:create("land.png")
                spriteLand:setPosition(200 + j * 180 - i % 2 * 90, 10 + i * 95 / 2)
                layerFarm:addChild(spriteLand)
            end
        end

        -- add crop
        local frameCrop = CCSpriteFrame:create("crop.png", CCRectMake(0, 0, 105, 95))
        for i = 0, 3 do
            for j = 0, 1 do
                local spriteCrop = CCSprite:createWithSpriteFrame(frameCrop);
                spriteCrop:setPosition(10 + 200 + j * 180 - i % 2 * 90, 30 + 10 + i * 95 / 2)
                layerFarm:addChild(spriteCrop)
            end
        end

        -- add moving dog
        local spriteDog = creatDog()
        layerFarm:addChild(spriteDog)
        
        
        -- handing touch events
        local touchBeginPoint = nil
        
        --触摸开始
        local function onTouchBegan(x, y)
            cclog("onTouchBegan: %0.2f, %0.2f", x, y)
            touchBeginPoint = {x = x, y = y}
            spriteDog.isPaused = true
            -- CCTOUCHBEGAN event must return true
            return true
        end
        
        --触摸移动
        local function onTouchMoved(x, y)
            cclog("onTouchMoved: %0.2f, %0.2f", x, y)
            if touchBeginPoint then
                local cx, cy = layerFarm:getPosition()
                layerFarm:setPosition(cx + x - touchBeginPoint.x,
                                      cy + y - touchBeginPoint.y)
                touchBeginPoint = {x = x, y = y}
            end
        end
        
        --触摸结束
        local function onTouchEnded(x, y)
            cclog("onTouchEnded: %0.2f, %0.2f", x, y)
            touchBeginPoint = nil
            spriteDog.isPaused = false
        end
        
        --触屏事件获得eventType:began/moved/ended
        local function onTouch(eventType, x, y)
            if eventType == "began" then   
                return onTouchBegan(x, y)
            elseif eventType == "moved" then
                return onTouchMoved(x, y)
            else
                return onTouchEnded(x, y)
            end
        end

        --注册Targeted触屏事件
        layerFarm:registerScriptTouchHandler(onTouch)
        
        layerFarm:setTouchEnabled(true)

        return layerFarm
    end


    -- create menu
    local function createLayerMenu()
        local layerMenu = CCLayer:create()

        local menuPopup, menuTools, effectID

        local function menuCallbackClosePopup()
            -- stop test sound effect
            SimpleAudioEngine:sharedEngine():stopEffect(effectID)
            menuPopup:setVisible(false)
        end

        local function menuCallbackOpenPopup()
            -- loop test sound effect
            local effectPath = CCFileUtils:sharedFileUtils():fullPathForFilename("effect1.wav")
            effectID = SimpleAudioEngine:sharedEngine():playEffect(effectPath)
            menuPopup:setVisible(true)
        end
        
        -- add a popup menu
        local menuPopupItem = CCMenuItemImage:create("menu2.png", "menu2.png")
        menuPopupItem:setPosition(0, 0)
        menuPopupItem:registerScriptTapHandler(menuCallbackClosePopup)
        menuPopup = CCMenu:createWithItem(menuPopupItem)
        menuPopup:setPosition(origin.x + visibleSize.width / 2, origin.y + visibleSize.height / 2)
        menuPopup:setVisible(false)
        layerMenu:addChild(menuPopup)
        
        -- add the left-bottom "tools" menu to invoke menuPopup
        local menuToolsItem = CCMenuItemImage:create("menu1.png", "menu1.png")
        menuToolsItem:setPosition(0, 0)
        menuToolsItem:registerScriptTapHandler(menuCallbackOpenPopup)
        menuTools = CCMenu:createWithItem(menuToolsItem)
        local itemWidth = menuToolsItem:getContentSize().width
        local itemHeight = menuToolsItem:getContentSize().height
        menuTools:setPosition(origin.x + itemWidth/2, origin.y + itemHeight/2)
        layerMenu:addChild(menuTools)

        return layerMenu
    end

    -- play background music, preload effect

    -- uncomment below for the BlackBerry version
    -- local bgMusicPath = CCFileUtils:sharedFileUtils():fullPathForFilename("background.ogg")
    local bgMusicPath = CCFileUtils:sharedFileUtils():fullPathForFilename("background.mp3")
    SimpleAudioEngine:sharedEngine():playBackgroundMusic(bgMusicPath, true)
    local effectPath = CCFileUtils:sharedFileUtils():fullPathForFilename("effect1.wav")
    SimpleAudioEngine:sharedEngine():preloadEffect(effectPath)

    -- run
    local sceneGame = CCScene:create()
    sceneGame:addChild(createLayerFarm())
    sceneGame:addChild(createLayerMenu())
    CCDirector:sharedDirector():runWithScene(sceneGame)
end

xpcall(main, __G__TRACKBACK__)