search

Home  >  Article  >  Web Front-end  >  Share a snake special effects code implemented in html5

Share a snake special effects code implemented in html5

零下一度
零下一度Original
2017-05-04 15:12:006098browse

本篇小编为大家分享一个用html5实现的简单贪吃蛇特效代码，喜欢的小伙伴们可以看一下

<html>
    <head>
        <meta charset=&#39;utf-8&#39;/>
        <title>Snake</title>
    </head>
    <body>
        <canvas id="plank" style="border"></canvas>
        <script type="text/javascript">
            //内置大量BUG，I&#39;m sorry.
            var lev=100;                //定时器间隔时间
            var num=30;             //网格大小，现在是30x30
            var direction=3;            //0:up  1:down  2:left  3:right
            var handle;             //用于管理定时器
            var score=0;                //分数
            var pause=true;         //暂停使用
            var canvas = document.getElementById(&#39;plank&#39;);
            var context = canvas.getContext(&#39;2d&#39;);
            var snakex=new Array();     //存储蛇身x坐标，下同
            var snakey=new Array();
            var prize=new Array(-1,-1);     //食物的位置
  
            function rand(){            //产生随机数
                return parseInt(Math.random()*num);
            }
  
            function chk(x,y){          //检查是否结束，包括越界
                if(x<0||y<0) return false;
                if(x>num-1||y>num-1) return false;
                for (var i=0; i!=snakex.length-1;i++) {
                    if(snakex[i]==x&&snakey[i]==y) {return false;}
                };
                return true;
            }
  
            function drawScore(text){       //打印分数
                context.clearRect(0,0,300,25);
                context.fillText("Score:"+text,5,5);
            }
  
            function makeprize(){           //产生食物的位置
                var flag=false;
                var prizepre=new Array(2);  //使用链表会更好
                while(!flag){           //食物位置不能在蛇体内
                    flag=true;
                    prizepre[0]=rand();prizepre[1]=rand();
                    for (var i=0; i!=snakex.length;i++) {
                        if((snakex[i]==prizepre[0])&&(snakey[i]==prizepre[1])) {flag=false;}
                    }
                }
                prize=prizepre;
            }
  
            function runscore(x,y){     //判断是否吃到食物，并做处理
                if(prize[0]==x&&prize[1]==y){
                    score=score+1;
                    drawScore(score);
                    snakex[snakex.length]=prize[0];
                    snakey[snakey.length]=prize[1];
                    makeprize();
                    drawNode(prize[0],prize[1]);
                    return true;
                }
                return false;
            }
  
            function run(){             //定时器用来判断snake行进方向等等
                switch(direction){          //方向
                    case 0: snakex[snakex.length]=snakex[snakex.length-1];snakey[snakey.length]=snakey[snakey.length-1]-1;break;
                    case 1: snakex[snakex.length]=snakex[snakex.length-1];snakey[snakey.length]=snakey[snakey.length-1]+1;break;
                    case 2: snakex[snakex.length]=snakex[snakex.length-1]-1;snakey[snakey.length]=snakey[snakey.length-1];break;
                    case 3: snakex[snakex.length]=snakex[snakex.length-1]+1;snakey[snakey.length]=snakey[snakey.length-1];break;
                }
                if(!runscore(snakex[snakex.length-1],snakey[snakey.length-1])){
                    if(chk(snakex[snakex.length-1],snakey[snakey.length-1])==false) {
                        clearInterval(handle);
                        drawScore(&#39;\\tGame over&#39;);
                        return;
                    }
                    drawNode(snakex[snakex.length-1],snakey[snakey.length-1]);
                }
                clearNode(snakex[0],snakey[0]);
                snakex.shift();
                snakey.shift();
            }
  
            function drawNode(x,y){     //画点，共30X30个点（10*10像素算1个点）
                context.fillRect(x*10+1,y*10+31,10,10);
            }
  
            function clearNode(x,y){
                context.clearRect(x*10+1,y*10+31,10,10);
            }
  
            function init(){        //初始化，设置画布大小，启动定时器等等
                canvas.width = 510;
                canvas.height = 600;
                context.font = "normal 20px Airl";
                context.textBaseline = "top";
                context.fillText(&#39;P键开始/暂停，方向键控制&#39;,0,350);
                drawScore(&#39;&#39;);
                context.strokeRect(0,30,302,302);
                makeprize();
                drawNode(prize[0],prize[1]);
                snakex[0]=0;snakex[1]=1;snakex[2]=2;
                snakey[0]=0;snakey[1]=0;snakey[2]=0;
                drawNode(snakex[0],snakey[0]);drawNode(snakex[1],snakey[1]);drawNode(snakex[2],snakey[2]);
            }
  
            document.onkeydown=function(event){     //注册键盘事件，up，down，left，right，暂停键p
                var e = event || window.event;
                if(e&&e.keyCode==38){
                    direction=0;
                }
                if(e&&e.keyCode==40){
                    direction=1;
                }
                if(e&&e.keyCode==37){
                    direction=2;
                }
                if(e&&e.keyCode==39){
                    direction=3;
                }
                if(e&&e.keyCode==80){
                    if(pause) {pause=false;handle=setInterval(run,lev);}
                    else {pause=true;clearInterval(handle);}
                }
            }
  
  
            init();
        </script>
    </body>
</html>

【相关推荐】

1. 免费h5在线视频教程

2. HTML5 完整版手册

3. php.cn原创html5视频教程

The above is the detailed content of Share a snake special effects code implemented in html5. For more information, please follow other related articles on the PHP Chinese website!

Statement：
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Previous article：Share example code for making faces using HTML5 CanvasNext article：Share example code for making faces using HTML5 Canvas

Related articles

See more