How to add a Lens Flare effect in html canvas

Question

This code displays a circle: I want to add a lens flare (halo effect as in PhotoShop) over this. How to do it ?

var canvas = document.getElementById('myCanvas');
var context = canvas.getContext('2d');
var centerX = canvas.width / 2;
var centerY = canvas.height / 2;
var radius = 70;

context.beginPath();
context.arc(centerX, centerY, radius, 0, 2 * Math.PI, false);
context.fillStyle = 'pink';
context.fill();
context.lineWidth = 5;
context.strokeStyle = '#f0505f';
context.stroke();

body {
  margin: 0px;
  padding: 0px;
}

<canvas id="myCanvas" width="578" height="200"></canvas>

Answer 1

A lens flare effect overlays many smaller effects on top of your image to create the lens flare.

Here's a tutorial of which effects you will need for your lens-flare effect:

http://library.creativecow.net/articles/mylenium/lens_flare.php

And here's the html5 canvas techniques needed to create each effect.

I've been wanting to do a lens flare effect, but haven't had time to accomplish it.

So give it a go...if you have difficulties just post a question and I'd be glad to help.

Good luck with your project!

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