var?can1;
var?can2;

var?ctx1;
var?ctr2;

var?lastTime;
var?daltaTime;

var?canWidth;
var?canHeight;

var?bgPic?=?new?Image();
document.body.onload?=?game;
function?game(){
	init();
	lastTime?=?Date.now();
	daltaTime?=?0;
	//gameloop();
}
function?init(){
	can1?=?document.getElementById("canvas1");
	ctx1?=?can1.getContext('2d');

	can2?=?document.getElementById("canvas2");
	ctx2?=?can2.getContext('2d');

	bgPic.src?=?"./src/background.jpg";

	canWidth?=?can1.width;
	canHeight?=?can1.height;
	ctx2.drawImage(bgPic,?0,?0,?canWidth,?canHeight);
}

我想在調(diào)用init方法的時候畫，為什么會畫不出來