Property:
globalAlpha:
Canvas:
your browser does not support the canvas tag
Code:
var c=document.getElementById('myCanvas');
var ctx=c.getContext('2d');
ctx.fillStyle='red';
ctx.fillRect(20,20,75,50);
ctx.globalAlpha=0.5;
ctx.fillStyle='blue';
ctx.fillRect(50,50,75,50);
Click the property values above to see the result
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