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POSeamless drawing in multiple canvas
 

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  1. POSeamless drawing in multiple canvas
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    <p>I'm trying to make a simple drawing tool using JS and Canvas element. My problem is that I would like to have several canvases and user should be able to draw one line through all of them. Here's a little page I did:</p> <pre><code>&lt;!DOCTYPE html&gt; &lt;html&gt; &lt;head&gt; &lt;script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.3/jquery.min.js"&gt;&lt;/script&gt; &lt;script type="text/javascript"&gt; var act = null; var context = null; var draw = false; var c = false; function boot() { $('.can') .mouseenter(function(){ act = this; context = act.getContext('2d'); // console.log(this); }) .mouseleave(function(){ act = null; context = null; // console.log('out'); }) .mousedown(function(){ draw = true; }) .mouseup(function(){ draw = false; }) .mousemove(function(ev){ // console.log(act); if (ev.layerX || ev.layerX == 0) { // Firefox x = ev.layerX; y = ev.layerY; } else if (ev.offsetX || ev.offsetX == 0) { // Opera x = ev.offsetX; y = ev.offsetY; } if(draw &amp;&amp; context != null) if (!c) { context.beginPath(); context.moveTo(x, y); c = true; } else { context.lineTo(x, y); context.stroke(); } }); } $(document).ready(boot); &lt;/script&gt; &lt;style&gt; .can {border: 1px solid blue; display:block; float:left; margin:0;} &lt;/style&gt; &lt;/head&gt; &lt;body&gt; &lt;canvas class="can" id="c2" width="200" height="200"&gt;&lt;/canvas&gt; &lt;canvas class="can" id="c1" width="200" height="200"&gt;&lt;/canvas&gt; &lt;canvas class="can" id="c3" width="200" height="200"&gt;&lt;/canvas&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>And it partially works: I can draw only in the first canvas. I debugged it and i got really confused, because the context changes as expected and drawing is enabled only in the first canvas.</p> <p>Any ideas what's the cause of such behavior? </p>
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    1. COThis is very, very odd. I'm running into even more unlikely problems on my jsfiddle of this. I'll keep you abreast of any progress I make.
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    2. COOK...found the problem :)
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