I found the answer in http://opensource.adobe.com/wiki/display/flexsdk/FXG+1.0+Specification http://opensource.adobe.com/wiki/display/flexsdk/FXG+1.0+Spe.... Th

I found the answer in http://opensource.adobe.com/wiki/display/flexsdk/FXG+1.0+Specification http://opensource.adobe.com/wiki/display/flexsdk/FXG+1.0+Spe.... The HTML5 Canvas support is just a Javascript-based interpreter for these FXG files, as you can see when they zoom in on the source code in the video.: "When initial work on an XML-based graphics interchange format began, the natural first thought was to use SVG. However, there are key differences between SVG and Flash Player's graphics capabilities. These include core differences in SVG and Flash's rendering model with regards to filters, transforms and text. Additionally, the interchange format needed to be able to support future Flash Player features, which would not necessarily map to SVG features. As such, the decision was made to go with a new interchange format, FXG, instead of having a non-standard implementation of SVG. FXG does borrow from SVG whenever possible. "It is important to note that this specification follows much of the SVG specification format organization as well as copying related concept prose. The SVG specification is available at http://www.w3.org/TR/SVG/. http://www.w3.org/TR/SVG/.