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Thursday, April 26, 2007

Googler on Flash vs SVG+VML

In Seeking Alpha’s ongoing Q&A with the Google Finance product manager, my question was:

Google Finance is one of the rather rare Google apps which makes use of Flash. I’m curious, at Google what considerations go into deciding whether to go for Flash or DHTML/ Ajax/ browser vector languages like SVG?

For instance, I noticed that Google Spreadsheets makes use of the browser’s native vector languages instead of Flash for their charts (e.g. Firefox has SVG and Internet Explorer has VML, and Google has libraries that wrap both). Here’s Google engineer Vivi Costache’s answer:

Until one year ago, since FF1.5 was not supporting SVG natively, the problem was simple – Flash was the way to go. Now, one might take into account the following:

1. Features that might potentially end up in your product. Things like video, animation, special effects, and sound are currently things that Flash can do and SVG can’t. SVG is just vector graphics, Flash is more than that.

2. Development effort. In flash you write the code only once and it most likely renders the same in any browser that has the flash player. SVG+VML will have to be tested in each and every browser, Javascript has a lot of particularities in each one so the effort of developing and maintaining will potentially be bigger.

3. The new Flash Player is a lot faster and more modern that older flash players. You can do more, and do so faster and easier than SVG since the flash player is lightning fast.

Right now, SVG is great if you want simple vector graphics to display. If you suspect there may be features not supported by SVG, I would go with Flash.



