基于HTML5坦克大战游戏简化版

window.addEventListener("load", canvasApp, false);    
//是否支持canvas
function canvasSupport () {
      return Modernizr.canvas;
}
function canvasApp() {
    //是否支持canvas
    if (!canvasSupport()) {
             return;
          }
    var theCanvas = document.getElementById("canvasOne");
    var context = theCanvas.getContext("2d");
    var tank=new Image();
    tank.addEventListener(‘load‘, start, false);
    tank.src="tanks_sheet.png"
    //Background
    context.fillStyle = "#CCCCCC";
    context.fillRect(0, 0, theCanvas.width, theCanvas.height);
    //Box
    context.lineWidth=16;
    context.strokeStyle = "#000000"; 
    context.strokeRect(8,8, theCanvas.width-16, theCanvas.height-16);
    //画我方tank和我方炮弹
    function drawtank() {
        if(gameover){
            context.save();
            context.fillStyle = "#000000";
            context.font = "normal bold 50px normal"; 
            context.fillText("游戏结束", 150, 150);
            context.restore();
            context.save();
            context.fillStyle = "#000000";
            context.font = "normal bold 25px normal"; 
            context.fillText("按空格键重新开始游戏", 125, 200);
            context.restore();
            update();
            return;
        }
        update();
        drawScene();
        render();
        //画场景
        function drawScene(){
            for(var i=0;i<=10;i++){
                for(var j=0;j<=14;j++){
                    colCtr=j*32+16;
                    rowCtr=i*32+16;
                    context.save();
                    sourceX=Math.floor(scene[i][j]%8)*32;
                    sourceY=Math.floor(scene[i][j]/8)*32;
                    context.drawImage(tank, sourceX,sourceY,32,32,colCtr,rowCtr,32,32);
                    context.restore();
                }
            }    
        }
        //坦克更新数据
        function update(){
            tankmove.x=tankmove.nextx;
            tankmove.y=tankmove.nexty;
            //左
            if(keyPressList[37]==true){
                //playermove.play();
                //playermove.stop();
                if(gameover){

                    return;
                }
                space();
                tankmove.tankAngle=270;
                tankmove.nextx-=tankmove.tankspeed;
                tankmove.tankshape=tankmove.tanknextshape;
                if(scene[Math.floor((tankmove.nexty-12)/32)][Math.floor((tankmove.nextx-12)/32)]!=0||scene[Math.ceil((tankmove.nexty-20)/32)][Math.floor((tankmove.nextx-12)/32)]!=0){
                    tankmove.nextx=tankmove.x;
                    tankmove.nexty=tankmove.y;
                    return;
                }
                tankmove.tanknextshape+=1;
                if(tankmove.tanknextshape>8){
                    tankmove.tanknextshape=1;
                }
                return;
            }
            //右
            if(keyPressList[39]==true){
                if(gameover){

                    return;
                }
                space();
                tankmove.tankAngle=90;
                tankmove.nextx+=tankmove.tankspeed;
                tankmove.tankshape=tankmove.tanknextshape;
                if(scene[Math.ceil((tankmove.nexty-20)/32)][Math.ceil((tankmove.nextx-20)/32)]!=0||scene[Math.floor((tankmove.nexty-12)/32)][Math.ceil((tankmove.nextx-20)/32)]!=0){
                    tankmove.nextx=tankmove.x;
                    tankmove.nexty=tankmove.y;
                    return;
                }
                tankmove.tanknextshape+=1;
                if(tankmove.tanknextshape>8){
                    tankmove.tanknextshape=1;
                }
                return;
            }
            //上
            if(keyPressList[38]==true){
                if(gameover){

                    return;
                }
                space();
                tankmove.tankAngle=0;
                tankmove.nexty-=tankmove.tankspeed;
                tankmove.tankshape=tankmove.tanknextshape;
                if(scene[Math.floor((tankmove.nexty-12)/32)][Math.floor((tankmove.nextx-12)/32)]!=0||scene[Math.floor((tankmove.nexty-12)/32)][Math.ceil((tankmove.nextx-20)/32)]!=0){
                    tankmove.nextx=tankmove.x;
                    tankmove.nexty=tankmove.y;
                    return;
                }
                tankmove.tanknextshape+=1;
                if(tankmove.tanknextshape>8){
                    tankmove.tanknextshape=1;
                }
                return;
            }
            //下
            if(keyPressList[40]==true){
                if(gameover){

                    return;
                }
                space();
                tankmove.tankAngle=180;
                tankmove.nexty+=tankmove.tankspeed;
                tankmove.tankshape=tankmove.tanknextshape;
                if(scene[Math.ceil((tankmove.nexty-20)/32)][Math.ceil((tankmove.nextx-20)/32)]!=0||scene[Math.ceil((tankmove.nexty-20)/32)][Math.floor((tankmove.nextx-12)/32)]!=0){
                    tankmove.nextx=tankmove.x;
                    tankmove.nexty=tankmove.y;
                    return;
                }
                tankmove.tanknextshape+=1;
                if(tankmove.tanknextshape>8){
                    tankmove.tanknextshape=1;
                }
                return;
            }
            space()
            //空格，发射炮弹
            function space(){
                if(keyPressList[32]==true){
                    if(gameover){
                        location.reload();
                    }
                    if(shell.shellflage){
                        return;
                    }
                    if(tankmove.nextx<0){
                        return;
                    }
                    else{
                        shootSound.play();
                        shell.shellflage=true;
                        shell.nextx=tankmove.nextx;
                        shell.nexty=tankmove.nexty;
                        shell.shellAngle=tankmove.tankAngle;
                        if(shellInterval){
                            clearInterval(shellInterval);
                            shellInterval=null;
                        }
                        shellInterval=setInterval(drawshell, 33);
                    }
                }
            }    
        }

        //坦克实施
        function render(){
            context.save();
            context.setTransform(1,0,0,1,0,0)
            var angleInRadians =tankmove.tankAngle * Math.PI / 180;
            context.translate(tankmove.x+16, tankmove.y+16)
            context.rotate(angleInRadians);
            var tankshapeX=Math.floor(tankmove.tankshape%8)*32;
            var tankshapeY=Math.floor(tankmove.tankshape/8)*32;
            context.drawImage(tank, tankshapeX, tankshapeY,32,32,-16,-16,32,32);
            context.restore();

            context.clearRect(496,16,138,352);
            context.fillStyle = "#3cb371";
            context.fillRect(496,16,138,352);
            context.save();
            context.fillStyle = "#000000";
            context.font = "italic bold 23px serif"; 
            context.fillText("关  卡:"+level+"", 500, 80);
            context.fillText("敌  人:"+surplus+"", 500, 110); 
            context.fillText("生  命:"+life+"", 500, 140); 
            context.fillText("得  分:"+score+"", 500, 170); 
            context.fillText("最高分:"+record+"", 500, 200);
            context.restore();

            context.save();
            context.fillStyle = "#000000";
            context.font = "normal bold 15px normal"; 
            context.fillText("游戏说明: 玩家", 500, 270);
            context.fillText("操控坦克进行战", 500, 290); 
            context.fillText("斗，击毁敌方得", 500, 310); 
            context.fillText("分，被击毁或相", 500, 330); 
            context.fillText("相撞减分。", 500, 350);
            context.restore();

        }
        //画炮弹
        function drawshell(){
            if(gameover){
                return;
            }
            shellupdate()
            shellrender()
            //炮弹发射数据更新
            function shellupdate(){
                if(shell.shellAngle==0){
                    shell.nexty-=shell.shellspeed;
                    var i=scene[Math.floor((shell.nexty-12)/32)][Math.floor((shell.nextx)/32)];
                    scene[Math.floor((shell.nexty-12)/32)][Math.floor((shell.nextx)/32)]=hitwall(i);
                }
                if(shell.shellAngle==90){
                    shell.nextx+=shell.shellspeed;
                    var i=scene[Math.floor((shell.nexty)/32)][Math.floor((shell.nextx+12)/32)];
                    scene[Math.floor((shell.nexty)/32)][Math.floor((shell.nextx+12)/32)]=hitwall(i);
                }
                if(shell.shellAngle==180){
                    shell.nexty+=shell.shellspeed;
                    var i=scene[Math.floor((shell.nexty+12)/32)][Math.floor((shell.nextx)/32)];
                    scene[Math.floor((shell.nexty+12)/32)][Math.floor((shell.nextx)/32)]=hitwall(i);
                }
                if(shell.shellAngle==270){
                    shell.nextx-=shell.shellspeed;
                    var i=scene[Math.floor((shell.nexty)/32)][Math.floor((shell.nextx-12)/32)];
                    scene[Math.floor((shell.nexty)/32)][Math.floor((shell.nextx-12)/32)]=hitwall(i);
                }
                //检测炮弹是否撞墙
                function hitwall(i){
                    switch(i){
                        case 26:
                            if(shellInterval){
                                clearInterval(shellInterval);
                                shellInterval=null;
                            }
                            setTimeout(function(){shell.shellflage=false},300);
                            shell.nextx=-500;
                            shell.nexty=-500;
                            return 0;
                            break

                        case 31:    
                            if(shellInterval){
                                clearInterval(shellInterval);
                                shellInterval=null;
                            }
                            setTimeout(function(){shell.shellflage=false},300);
                            shell.nextx=-500;
                            shell.nexty=-500;
                            return i;
                            break
                        case 30:    
                            if(shellInterval){
                                clearInterval(shellInterval);
                                shellInterval=null;
                            }
                            setTimeout(function(){shell.shellflage=false},300);
                            shell.nextx=-500;
                            shell.nexty=-500;
                            return i;
                            break
                        default:
                            return 0;
                    }
                }                    
            }
            //炮弹发射实施
            function shellrender(){
                shell.x=shell.nextx;
                shell.y=shell.nexty;
                context.save();
                context.setTransform(1,0,0,1,0,0)
                var shellangleInRadians =shell.shellAngle * Math.PI / 180;
                context.translate(shell.x+16, shell.y+16)
                context.rotate(shellangleInRadians);
                var shellshapeX=Math.floor(shell.shellshape%8)*32;
                var shellshapeY=Math.floor(shell.shellshape/8)*32;
                context.drawImage(tank, shellshapeX, shellshapeY,32,32,-16,-16,32,32);
                context.restore();
            }
        }        
    }
    //画敌军坦克
    function drawenemy(){
        if(gameover){
            return;
        }
        for(var enemytanknum=0;enemytanknum<=2;enemytanknum++){
            var enemytank=enemy[enemytanknum];
            //enemyrmove.play();
            enemyupdate();
            enemyrender();
        }
        function enemyupdate(){
            enemytank.shapenum=(0.1+enemytank.shapenum)%8+9;//减慢滚带的速度
            enemytank.enemytankshape=Math.floor(enemytank.shapenum);
            //下
            if(enemytank.enemytankAngle==180){
                swerve()
                enemytank.nexty+=enemytank.enemytankspeed;
                if(scene[Math.ceil((enemytank.nexty-20)/32)][Math.ceil((enemytank.nextx-20)/32)]!=0||scene[Math.ceil((enemytank.nexty-20)/32)][Math.floor((enemytank.nextx-12)/32)]!=0){
                    enemyhitwall()
                }
            }
            //左
            if(enemytank.enemytankAngle==270){
                swerve()
                enemytank.nextx-=enemytank.enemytankspeed;
                if(scene[Math.floor((enemytank.nexty-12)/32)][Math.floor((enemytank.nextx-12)/32)]!=0||scene[Math.ceil((enemytank.nexty-20)/32)][Math.floor((enemytank.nextx-12)/32)]!=0){
                    enemyhitwall()
                }
            }
            //右
            if(enemytank.enemytankAngle==90){
                swerve()
                enemytank.nextx+=enemytank.enemytankspeed;
                if(scene[Math.ceil((enemytank.nexty-20)/32)][Math.ceil((enemytank.nextx-20)/32)]!=0||scene[Math.floor((enemytank.nexty-12)/32)][Math.ceil((enemytank.nextx-20)/32)]!=0){
                    enemyhitwall()
                }
            }
            //上
            if(enemytank.enemytankAngle==0){
                swerve()
                enemytank.nexty-=enemytank.enemytankspeed;
                if(scene[Math.floor((enemytank.nexty-12)/32)][Math.floor((enemytank.nextx-12)/32)]!=0||scene[Math.floor((enemytank.nexty-12)/32)][Math.ceil((enemytank.nextx-20)/32)]!=0){
                    enemyhitwall()
                }
            }
            //随机发射炮弹
            var enemyfire=Math.floor(Math.random() * 100);
            if(enemyfire==0){
                if(enemyshell.shellflage){
                    return;
                }
                if(enemytank.nextx<0){
                    return;
                }
                else{
                    enemyshell.shellflage=true;
                    enemyshell.nextx=enemytank.nextx;
                    enemyshell.nexty=enemytank.nexty;
                    enemyshell.shellAngle=enemytank.enemytankAngle;
                    if(enemyshellInterval){
                        clearInterval(enemyshellInterval);
                        enemyshellInterval=null;
                    }
                    enemyshellInterval=setInterval(enemyrdrawshell, 33);
                }
            }
            //检测是否打击到目标
            if(impact(shell,enemytank)){
                if(shellInterval){
                    clearInterval(shellInterval);
                    shellInterval=null;
                }
                score++;
                if(score>=record){
                    record=score;
                    localStorage.record=record;
                }
                if(score>=level*5){
                    level++;
                    if(level>=5){
                        gameover=true;
                        return
                    }
                    scene=scenenum[(level-1)%4];
                    for(var enemynum=0;enemynum<=2;enemynum++){
                    var tempx=48+enemynum*192;
                    //敌军坦克
                    tempenemytank={appearx:tempx,appeary:48,x:tempx,y:48,nextx:tempx,nexty:48,enemytankspeed:Speed+level*0.5,enemytankAngle:180,enemytankshape:0,shapenum:0};
                    enemy[enemynum]=tempenemytank;
                    }
                    tankmove={appearx:240,appeary:304,x:240,y:304,nextx:240,nexty:304,tankAngle:Angle,tankspeed:Speed,tankshape:shape,tanknextshape:shape};
                    enemyshell={x:0,y:0,nextx:0,nexty:0,shellspeed:Speed+level*0.5+2,shellshape:21,shellAngle:Angle,shellflage:false};
                    surplus=6;
                }
                surplus--;
                setTimeout(function(){shell.shellflage=false},300);
                explode(enemytank)
                enemytank.nextx=-500;
                shell.nextx=-500;
                shell.nexty=-500;
            }
            //检测是否打击到玩家
            if(impact2(enemyshell,tankmove)){
                if(invincible){
                    return;
                }
                if(enemyshellInterval){
                    clearInterval(enemyshellInterval);
                    enemyshellInterval=null;
                }
                life--;
                if(life<=0){
                    gameover=true;
                    return;
                }
                invincible=true;
                setTimeout(function(){invincible=false},2000)
                explode(tankmove)
                setTimeout(function(){enemyshell.shellflage=false},300);
                tankmove.nextx=-500;
                enemyshell.nextx=-500;
                enemyshell.nexty=-500;
            }
            //与敌人相撞
            if(impact(enemytank,tankmove)){
                if(enemyshellInterval){
                    clearInterval(enemyshellInterval);
                    enemyshellInterval=null;
                }
                if(invincible){
                    return;
                }
                invincible=true;
                setTimeout(function(){invincible=false},2000)
                life--;
                if(life<=0){
                    gameover=true;
                    return;
                }
                explode(tankmove)
                tankmove.nextx=-500;

            }
            //自动转向
            function swerve(){
                var j=Math.floor(Math.random() * 100);
                if(j==0){
                    enemytank.enemytankAngle+=90;
                }
                if(j==1){
                    enemytank.enemytankAngle-=90;
                }
                enemytank.enemytankAngle=(enemytank.enemytankAngle+360)%360;
            }
            //撞墙转向
            function enemyhitwall(){
                enemytank.nextx=enemytank.x;
                enemytank.nexty=enemytank.y;
                var j=Math.floor(Math.random() * 2);
                if(j==0){
                    enemytank.enemytankAngle+=90;
                }
                else{
                    enemytank.enemytankAngle-=90;
                }
                enemytank.enemytankAngle=(enemytank.enemytankAngle+360)%360;
            }
        }
        //敌军tank
        function enemyrender(){
            enemytank.x=enemytank.nextx;
            enemytank.y=enemytank.nexty;
            context.save();
            context.setTransform(1,0,0,1,0,0)
            var enemyangleInRadians =enemytank.enemytankAngle * Math.PI / 180;
            context.translate(enemytank.x+16, enemytank.y+16)
            context.rotate(enemyangleInRadians);
            var enemyshapeX=Math.floor(enemytank.enemytankshape%8)*32;
            var enemyshapeY=Math.floor(enemytank.enemytankshape/8)*32;
            context.drawImage(tank, enemyshapeX, enemyshapeY,32,32,-16,-16,32,32);
            context.restore();    
        }
        //画炮弹
        function enemyrdrawshell(){
            if(gameover){
                return;
            }
            enemyrshellupdate()
            enemyrshellrender()
            //炮弹发射数据更新
            function enemyrshellupdate(){
                if(enemyshell.shellAngle==0){
                    enemyshell.nexty-=enemyshell.shellspeed;
                    var i=scene[Math.floor((enemyshell.nexty-0)/32)][Math.floor((enemyshell.nextx)/32)];
                    scene[Math.floor((enemyshell.nexty-0)/32)][Math.floor((enemyshell.nextx)/32)]=hitwall(i);
                }
                if(enemyshell.shellAngle==90){
                    enemyshell.nextx+=enemyshell.shellspeed;
                    var i=scene[Math.floor((enemyshell.nexty)/32)][Math.floor((enemyshell.nextx+0)/32)];
                    scene[Math.floor((enemyshell.nexty)/32)][Math.floor((enemyshell.nextx+0)/32)]=hitwall(i);
                }
                if(enemyshell.shellAngle==180){
                    enemyshell.nexty+=enemyshell.shellspeed;
                    var i=scene[Math.floor((enemyshell.nexty+0)/32)][Math.floor((enemyshell.nextx)/32)];
                    scene[Math.floor((enemyshell.nexty+0)/32)][Math.floor((enemyshell.nextx)/32)]=hitwall(i);
                }
                if(enemyshell.shellAngle==270){
                    enemyshell.nextx-=enemyshell.shellspeed;
                    var i=scene[Math.floor((enemyshell.nexty)/32)][Math.floor((enemyshell.nextx-0)/32)];
                    scene[Math.floor((enemyshell.nexty)/32)][Math.floor((enemyshell.nextx-0)/32)]=hitwall(i);
                }
                //检测炮弹是否撞墙
                function hitwall(i){
                    switch(i){
                        case 26:
                            if(enemyshellInterval){
                                clearInterval(enemyshellInterval);
                                enemyshellInterval=null;
                            }
                            setTimeout(function(){enemyshell.shellflage=false},300);
                            enemyshell.nextx=-500;
                            enemyshell.nexty=-500;
                            return 0;
                            break

                        case 31:    
                            if(enemyshellInterval){
                                clearInterval(enemyshellInterval);
                                enemyshellInterval=null;
                            }
                            setTimeout(function(){enemyshell.shellflage=false},300);
                            enemyshell.nextx=-500;
                            enemyshell.nexty=-500;
                            return i;
                            break
                        case 30:    
                            if(enemyshellInterval){
                                clearInterval(enemyshellInterval);
                                enemyshellInterval=null;
                            }
                            setTimeout(function(){enemyshell.shellflage=false},300);
                            enemyshell.nextx=-500;
                            enemyshell.nexty=-500;
                            return i;
                            break
                        default:
                            return 0;
                    }
                }                    
            }
            //炮弹发射实施
            function enemyrshellrender(){
                enemyshell.x=enemyshell.nextx;
                enemyshell.y=enemyshell.nexty;
                context.save();
                context.setTransform(1,0,0,1,0,0)
                var shellangleInRadians =enemyshell.shellAngle * Math.PI / 180;
                context.translate(enemyshell.x+16, enemyshell.y+16)
                context.rotate(shellangleInRadians);
                var shellshapeX=Math.floor(enemyshell.shellshape%8)*32;
                var shellshapeY=Math.floor(enemyshell.shellshape/8)*32;
                context.drawImage(tank, shellshapeX, shellshapeY,32,32,-16,-16,32,32);
                context.restore();
            }
        }
    }
    //检测撞击
    function impact(one,two){
        var dx=one.nextx-two.nextx;
        var dy=one.nexty-two.nexty;
        var distance=Math.sqrt(dx*dx+dy*dy)
        if(distance<=26){
            return true;
        }
        else{
            return false;
        }
    }
    //检测撞击
    function impact2(one,two){
        var dx=one.nextx-two.nextx;
        var dy=one.nexty-two.nexty;
        var distance=Math.sqrt(dx*dx+dy*dy)
        if(distance<=26){
            return true;
        }
        else{
            return false;
        }
    }
    //爆炸
    function explode(dietank){
        explodeSound.play();
        var x=dietank.x;
        var y=dietank.y;
        var times=0;
        var dietankInterval=setInterval(function(){
            drawdietank(17+Math.floor(times/10));
            times++;
            if(times>29){
                clearInterval(dietankInterval);
                setTimeout(function(){dietank.shellflage=false},300);
                if(dietank.appeary==48){
                    if(surplus<=2){
                        dietank.enemytankspeed=0;
                        return;
                    }    
                }
                dietank.nextx=dietank.appearx;
                dietank.nexty=dietank.appeary;
            }
        },15)
        function drawdietank(dietankshape){
            context.save();
            context.setTransform(1,0,0,1,0,0)
            context.translate(x+16, y+16)
            var dietankshapeX=Math.floor(dietankshape%8)*32;
            var dietankshapeY=Math.floor(dietankshape/8)*32;
            context.drawImage(tank, dietankshapeX, dietankshapeY,32,32,-16,-16,32,32);
            context.restore();    
        }
    }
    var score=0;//分数
    var level=1;//关卡
    var surplus=5;//剩余敌人数量
    var life=3;//生命
    var invincible=false//无敌
    var storage = window.localStorage;//"localStorage"HTML5存储数据
    if(storage.length==0){
        localStorage.record=0;
    }
    var record=localStorage.record;//最高分
    var gameover=false;
    var enemyInterval=null;//敌人timer
    var tankInterval=null;//玩家timer
    var Speed=3;//运动的速度
    var Angle=0;//tank面向方向
    var shape=1;//tank当前状态
    //坦克数组
    tankmove={appearx:240,appeary:304,x:240,y:304,nextx:240,nexty:304,tankAngle:Angle,tankspeed:Speed,tankshape:shape,tanknextshape:shape};
    //炮弹数组
    shell={x:0,y:0,nextx:0,nexty:0,shellspeed:Speed+4,shellshape:20,shellAngle:Angle,shellflage:false};
    //敌军数组
    var enemy=new Array();
    //敌军炮弹数组
    var enemyshell={x:0,y:0,nextx:0,nexty:0,shellspeed:Speed+2,shellshape:21,shellAngle:Angle,shellflage:false};
    //场景数组
    var scenenum=[[
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30],
    [31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,31],
    [31, 0, 0, 0,26,26, 0, 0, 0,26,26, 0, 0, 0,31],
    [31, 0, 0,26, 0, 0,26, 0,26, 0, 0,26, 0, 0,31],
    [31, 0, 0,26, 0, 0, 0,26, 0, 0, 0,26, 0, 0,31],
    [31,26, 0, 0,26, 0, 0, 0, 0, 0,26, 0, 0,26,31],
    [31,26, 0, 0, 0,26, 0, 0, 0,26, 0, 0, 0,26,31],
    [31,26, 0, 0, 0, 0,26, 0,26, 0, 0, 0, 0,26,31],
    [31,26,26,26,26, 0, 0,26, 0, 0,26,26,26,26,31],
    [31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,31],
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30]
    ],
    [
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30],
    [31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,31],
    [31, 0,26,26,26,26,0, 0,0,26,26, 26,26,0,31],
    [31, 0, 0, 0, 0,26, 0, 0, 0, 26,0, 0, 0, 0,31],
    [31,26,26,26, 26,26,26,26,26,26,26,26, 26,26,31],
    [31, 0, 26, 0, 0, 0, 0,26, 0, 0, 0, 0, 26,0,31],
    [31,26, 26,0,26,26,26,26,26,26,26, 0,26,26,31],
    [31, 0, 0, 0, 0, 26,0, 0, 0,26, 0, 0, 0, 0,31],
    [31,26,26,26,26, 0, 0,0,0,0, 26,26,26,26,31],
    [31, 0, 0,26, 26, 0, 0, 0, 0, 0, 26,26, 0, 0,31],
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30]
    ],
    [
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30],
    [31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,31],
    [31, 0,26,26,26,26,26, 0,26,26,26,26,26, 0,31],
    [31, 0,26, 0, 0, 0,26, 0,26, 0, 0, 0,26, 0,31],
    [31, 0,26, 0, 0, 0,26, 0,26, 0, 0, 0,26, 0,31],
    [31, 0,26, 0, 0, 0,26, 0,26,26,26,26,26, 0,31],
    [31, 0,26, 0, 0, 0,26, 0, 0, 0, 0, 0,26, 0,31],
    [31, 0,26, 0, 0, 0,26, 0,26, 0, 0, 0,26, 0,31],
    [31, 0,26,26,26,26,26, 0,26,26,26,26,26, 0,31],
    [31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,31],
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30]
    ],
    [
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30],
    [31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,31],
    [31, 0,26,26,26,26,26, 0,26,26,26, 0,26,26,31],
    [31, 0, 0, 0, 0,26, 0, 0, 0, 0,26, 0, 0, 0,31],
    [31,26,26,26, 0,26,26,26,26,26,26,26, 0,26,31],
    [31, 0, 0, 0, 0, 0, 0,26, 0, 0, 0, 0, 0,26,31],
    [31,26, 0,26,26,26,26,26,26,26,26, 0,26,26,31],
    [31, 0, 0, 0, 0, 0,26, 0, 0,26, 0, 0, 0, 0,31],
    [31,26,26,26,26, 0, 0,26,26,26, 0,26,26,26,31],
    [31, 0, 0,26, 0, 0, 0, 0, 0, 0, 0,26, 0, 0,31],
    [30,30,30,30,30,30,30,30,30,30,30,30,30,30,30]
    ]]
    var scene=scenenum[(level-1)];
    //计时器控制炮弹发出
    var shellInterval=null;
    var enemyshellInterval=null;
    for(var enemynum=0;enemynum<=2;enemynum++){
        var tempx=48+enemynum*192;
    //敌军坦克
    tempenemytank={appearx:tempx,appeary:48,x:tempx,y:48,nextx:tempx,nexty:48,enemytankspeed:Speed-1,enemytankAngle:180,enemytankshape:0,shapenum:0};
    enemy[enemynum]=tempenemytank;
    }
    //键盘事件
    var keyPressList=[];
    document.onkeydown=function(e){
        e=e?e:window.event;
        keyPressList[e.keyCode]=true;
    }
    document.onkeyup=function(e){
        e=e?e:window.event;
        keyPressList[e.keyCode]=false;
    }
    //声音
    //爆炸
    var explodeSound = document.createElement("audio");
    document.body.appendChild(explodeSound);
    explodeSound.setAttribute("src", "explode1.mp3");
    explodeSound.valume=.5;
    //发射子弹
    var shootSound = document.createElement("audio");
    document.body.appendChild(shootSound);
    shootSound.setAttribute("src", "shoot1.mp3");
    shootSound.volume=.5;
    //玩家行走
    var playermove = document.createElement("audio");
    document.body.appendChild(playermove);
    playermove.setAttribute("src", "move1.mp3");
    playermove.valume=.001;
    //敌人行走
    var enemyrmove = document.createElement("audio");
    document.body.appendChild(enemyrmove);
    enemyrmove.setAttribute("src", "move2.mp3");
    enemyrmove.valume=.001;
    //游戏开始

    //游戏失败

    //开始游戏
    function start(){
        tankInterval=setInterval(drawtank, 33);
        enemyInterval=setInterval(drawenemy, 33);
    }
    //debug函数
    var debug = function(log){
        try{
            console.log(log);//safari可用
        }
        catch(e){}
    }
}
function supportedAudioFormat(audio) {
    var returnExtension = "";
    if (audio.canPlayType("audio/ogg") =="probably" || audio.canPlayType("audio/ogg") == "maybe") {
        returnExtension = "ogg";
    } else if(audio.canPlayType("audio/wav") =="probably" || audio.canPlayType("audio/wav") == "maybe") {
        returnExtension = "wav";
    } else if(audio.canPlayType("audio/mp3") == "probably" || audio.canPlayType("audio/mp3") == "maybe") {
        returnExtension = "mp3";
    }

    return returnExtension;

}