您好,登录后才能下订单哦!
密码登录
登录注册
点击 登录注册 即表示同意《亿速云用户服务条款》
这篇文章主要为大家详细介绍了canvas制作心电图的方法,文中示例代码介绍的非常详细,图文详解容易学习,非常适合初学者入门,感兴趣的小伙伴们可以参考一下。
思路:
1.模拟点(如果你有真实的数据,那就是把数据幻化成canvas对应的坐标点)
模拟点时注意的点就是高起部分需要对称以及为了好看要随机出现上上下下
2.画线
画线需要注意有一个匀速移动的过程。
比如 A点到B点,不是简单的A画到B,而是A点到A1,A2....最后到B(这一块按照比例移动比较难)
3.画线的一些效果,比如加上阴影(这里就可以自由发挥了)具体代码
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>心电图</title> <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no"> <style> html,body{ width: 100%; height: 100%; margin: 0; } canvas{ background: #000; width: 100%; height: 100%; } </style> </head> <body> <p id="canvas"> <canvas id="can"></canvas> </p> <script> var can = document.getElementById('can'), pan, index = 0, flag = true, wid = document.body.clientWidth, hei = document.body.clientHeight, x = 0, y = hei/2, drawX = 0, drawY = hei/2, drawXY = [], cDrawX = 0, i = 0, reX = 0, reY = 0; start(); function start(){ can.height = hei; can.width = wid; pan = can.getContext("2d"); pan.strokeStyle = "white"; pan.lineJoin = "round"; pan.lineWidth = 6; pan.shadowColor = "#228DFF"; pan.shadowOffsetX = 0; pan.shadowOffsetY = 0; pan.shadowBlur = 20; pan.beginPath(); pan.moveTo(x,y); drawXYS(); index = setInterval(move,1); }; function drawXYS(){ if(drawX > wid){ }else{ if(drawY == hei/2){ if(flag){ flag = false; }else{ var _y = Math.ceil(Math.random()*10); _y = _y/2; if(Number.isInteger(_y)){ drawY += Math.random()*180+30; }else{ drawY -= Math.random()*180+30; } flag = true; } cDrawX = Math.random()*40+15; }else{ drawY = hei/2; } drawX += cDrawX; drawXY.push({ x : drawX, y : drawY }); drawXYS(); } } function move(){ var x = drawXY[i].x, y = drawXY[i].y; if(reX >= x - 1){ reX = x; reY = y; i++; cc(); return; } if(y > hei/2){ if(reY >= y){ reX = x; reY = y; i++; cc(); return; } }else if(y < hei/2){ if(reY <= y){ reX = x; reY = y; i++; cc(); return; } }else{ reX = x; reY = y; i++; cc(); return; } reX += 1; if(y == hei/2){ reY = hei/2; }else{ var c = Math.abs((drawXY[i].x-drawXY[i-1].x)/(drawXY[i].y-drawXY[i-1].y)); var _yt = (reX-drawXY[i-1].x)/c; if(drawXY[i].y < drawXY[i-1].y){ reY = drawXY[i-1].y - _yt; }else{ reY = drawXY[i-1].y + _yt; } } cc(); } function cc(){ if(i == drawXY.length){ pan.closePath(); clearInterval(index); index = 0; x = 0; y = hei/2; flag = true; i = 0; }else{ pan.lineTo(reX, reY); pan.stroke(); } } </script> </body> </html>
以上就是canvas制作心电图的详细内容了,看完之后是否有所收获呢?如果想了解更多相关内容,欢迎关注亿速云行业资讯!
免责声明:本站发布的内容(图片、视频和文字)以原创、转载和分享为主,文章观点不代表本网站立场,如果涉及侵权请联系站长邮箱:is@yisu.com进行举报,并提供相关证据,一经查实,将立刻删除涉嫌侵权内容。