如何使用2幅画布 [英] how to use 2 canvases

问题描述

我想绘制模拟时钟。因此主画布将是拨号，小时和分钟箭头，第二个将是秒箭头（每1秒更新一次）。



HTML

I want to draw analog clock. So the main canvas will be dial and, hours and minutes arrows, and the second will be seconds arrow (for update every 1 second).

HTML

<canvas id="clock"></canvas>
<canvas id="second"></canvas>

JScript

JScript

canvas = document.getElementById('clock');
canvas.width = document.documentElement.clientWidth;
canvas.height = document.documentElement.clientHeight-6;
canvas = document.getElementById('second');
canvas.width = document.documentElement.clientWidth;
canvas.height = document.documentElement.clientHeight-6;

但是画布并不透明，我无法画画。有什么想法吗？



感谢您的关注。

But canvases are not transparent and I can not to draw. Any ideas?

Thank you for attention.

推荐答案

http://prajaktagodbole.com/blog/2011/02/analog-clock-using-html5-canvas- and -javascript / [ ^ ]

这篇关于如何使用2幅画布的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！