用仿ActionScript的语法来编写html5——第四篇，继承与简单的rpg

第四篇，继承与简单的rpg

这次用继承自LSprite的类来实现简单的rpg的demo
先看一下最后的代码与as的相似度

var backLayer;
//地图
var mapimg;
//人物
var playerimg;
var loader
var imageArray;
var loadIndex = 0;
var imgData = new Array({name:"back.jpg",img:null},{name:"1.png",img:null},{name:"2.png",img:null});
var chara;
var charaList;

function main(){
    loadImage();
}
function loadImage(){
    if(loadIndex >= imgData.length){
        gameInit();
        return;
    }
    loader = new LLoader();
    loader.addEventListener(LEvent.COMPLETE,loadComplete);
    loader.load(imgData[loadIndex].name,"bitmapData");
}
function loadComplete(event){
    imgData[loadIndex].img = loader.content;
    loadIndex++;
    loadImage();
}
function gameInit(event){
    var bitmapdata;
    bitmapdata = new LBitmapData(imgData[0].img);
    mapimg = new LBitmap(bitmapdata);

    document.getElementById("inittxt").innerHTML="";
    backLayer = new LSprite();
    addChild(backLayer);
    backLayer.addChild(mapimg);

    bitmapdata = new LBitmapData(imgData[1].img,0,0,70,92);
    imageArray = LGlobal.divideCoordinate(bitmapdata.image.width,bitmapdata.image.height,8,8);
    playerimg = new LBitmap(bitmapdata);
    chara = new CharacterSprite(true,playerimg,imageArray,0,0);
    backLayer.addChild(chara);

    charaList = new Array();
    for(var i=0;i<10;i++){
        bitmapdata = new LBitmapData(imgData[2].img,0,0,80,91);
        imageArray = LGlobal.divideCoordinate(bitmapdata.image.width,bitmapdata.image.height,8,8);
        playerimg = new LBitmap(bitmapdata);
        var npcx = parseInt(Math.random()*800/3)*3;
        var npcy = parseInt(Math.random()*480/3)*3;
        var npc = new CharacterSprite(false,playerimg,imageArray,npcx,npcy);
        backLayer.addChild(npc);
        charaList.push(npc);
    }

    backLayer.addEventListener(LEvent.ENTER_FRAME, onframe)
    backLayer.addEventListener(LMouseEvent.MOUSE_DOWN, onmousedown);
}

function onframe(){
    chara.onframe();

    for(var i=0;i<charaList.length;i++){
        charaList[i].onframe();
    }
}
function onmousedown(event){
    chara.toCoordinate.x = parseInt(event.selfX/3)*3;
    chara.toCoordinate.y = parseInt(event.selfY/3)*3;
}

应该还算可以吧？
看一下成果吧,看不到效果的请下载支持html5的浏览器
http://fsanguo.comoj.com/html5/jstoas03/index.html

下面说一说如何继承，继承的话，js没有办法像as那样继承，
js的继承看下面

function base(derive,baseSprite,baseArgs){
    baseSprite.apply(derive,baseArgs);

    for(prop in baseSprite.prototype){
        var proto = derive.constructor.prototype;
        if(!proto[prop]){
            proto[prop] = baseSprite.prototype[prop];
        }
    }
}

三个参数分别是child,base,base构造器参数数组
这个方法可以实现js的完美继承
现在来建立一个继承自LSprite的类CharacterSprite
只需要在构造器里调用base(this,LSprite,[])就可以实现继承
而且CharacterSprite因为继承了LSprite的方法，所以它有addChild等方法
CharacterSprite类代码如下

function CharacterSprite(ishero,bitmap,imageArray,x,y){
    base(this,LSprite,[]);
    var self = this;
    self.x = x;
    self.y = y;
    self.toCoordinate = {x:x,y:y};
    self.ishero = ishero;
    self.animeIndex = 0;
    self.dirindex = 0;
    self.dirmark = {"0,1":0,"-1,0":1,"1,0":2,"0,-1":3,"-1,1":4,"1,1":5,"-1,-1":6,"1,-1":7};

    self.bitmap = bitmap;
    self.imageArray = imageArray;
    self.addChild(bitmap);
}
CharacterSprite.prototype.onframe = function (){
    var self = this;
    self.animeIndex++;
    if(self.animeIndex >= self.imageArray[0].length){
        self.animeIndex = 0;
    }
    var markx = 0,marky = 0;
    var l = 3;
    if(self.x > self.toCoordinate.x){
        self.x -= l;
        markx = -1;
    }else if(self.x < self.toCoordinate.x){
        self.x += l;
        markx = 1;
    }
    if(self.y > self.toCoordinate.y){
        self.y -= l;
        marky = -1;
    }else if(self.y < self.toCoordinate.y){
        self.y += l;
        marky = 1;
    }
    if(markx !=0 || marky != 0){
        var mark = markx+","+marky;
        self.dirindex = self.dirmark[mark];
    }else if(!self.ishero){
        if(self.index > 0){
            self.index -= 1;
        }else{
            self.index = parseInt(Math.random()*300);
            self.toCoordinate.x = parseInt(Math.random()*800/3)*3;
            self.toCoordinate.y = parseInt(Math.random()*480/3)*3;
        }
    }
    self.bitmap.bitmapData.setCoordinate(self.imageArray[self.dirindex][self.animeIndex].x,self.imageArray[self.dirindex][self.animeIndex].y);

}

然后，准备好图片，按照最开始的代码，就可以完成rpg人物的添加移动等内容了

下一篇，也不知该研究什么了，先试着做个小游戏，然后看缺什么吧