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|ActionScript Class||Implementation Status||Notes|
SWF (starting at version 8) allows bitmap filters to be applied to display objects, that is, character instances (gnash::character). Adding filters implies that the display object will be cached as a bitmap.
I ("JucaBlues") have implemented some of the SVG Filters in Inkscape, which are similar to the ones defined in SWF spec. One of the renderers used by gnash is Cairo. From my experience in Inkscape I can tell that currently (September 2008) Cairo does not render filter primitives. All filtering code was written in Inkscape itself.
The ideal strategy would be to port Inkscape's filtering routines to libcairo and then use it in Gnash through its cairo renderer.