Shumway team still needs to implement filter effects available in the Flash Player. Ideally, fast filters can be made available to all Canvas programs. Now that we've got a shared filter pipeline with SVG and CSS, can we surface the same filters as a Canvas API?
I'm attaching our last e-mail thread on the subject for context. --Jet ----- Original Message ----- From: "Jeff Muizelaar" <[email protected]> To: "Tobias Schneider" <[email protected]> Cc: "Jet Villegas" <[email protected]>, "Benoit Jacob" <[email protected]>, "Joe Drew" <[email protected]>, "Boris Zbarsky" <[email protected]>, "L. David Baron" <[email protected]>, "Robert O'Callahan" <[email protected]>, "Jonas Sicking" <[email protected]>, "Bas Schouten" <[email protected]> Sent: Friday, July 20, 2012 8:17:44 AM Subject: Re: Native implementation of Flashs ColorMatrix filter This is not that easy for us to do. The only Azure backend that makes this easy is Skia. None of CoreGraphics, Cairo or Direct2D support this functionality. We could do hardware/software implementations on top of those APIs as we do with SVG but I'm not in a huge rush to do this work. -Jeff On 2012-07-19, at 9:20 AM, Jet Villegas wrote: > Here's a request from the Shumway team re: Canvas2D graphics. Can we surface > this API? > > -- Jet > > ----- Forwarded Message ----- > From: "Tobias Schneider" <[email protected]> > To: "Jet Villegas" <[email protected]> > Sent: Thursday, July 19, 2012 8:40:52 AM > Subject: Native implementation of Flashs ColorMatrix filter > > Hi Jet, > > as already discussed in some meetings, it would be big performance benefit > for Shumway if we could implement Flashs ColorMatrix filter natively as an > extension to the Canvas API. ColorMatrix filters (or more the > ColorTransformation, which can be easily converted to a ColorMatrix) are used > really often in Swiff files, e.g. there is no way no change a display objects > opacity except of using a color transformation (or via script of course), so > its really a highly needed feature for Shumway. And doing bitmap filter > operations pixel wise with plain Javascript is just too slow to archive a > decent frame rate (especially since Canvas is hardware accelerated, which > makes using getImageData a pain in the ass). > > You can find out more about the ColorMatirx filter in the SWF spec or here: > http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/filters/ColorMatrixFilter.html > > Firefox already implements a ColorMatrix filter in its SVG implementation, > but since SVG is currently using the Skaia graphics backend, I'm not sure if > its possible to use them internally within the Canvas API, which is based on > Azure/Cairo. > > So I digged a little bit deeper into Azure to see where it could be > implemented, and i think the way we blur pixels to draw shadows is kinda > similar. So maybe we can reuse a lot of that for additional bitmap filters. > > The Canvas API for it can look pretty simple, we just need a way to assign > the ColorMatrix values as an array to a context property like so: > > ctx.mozColorMatrix = [1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, > 1, 0]; > > I'm pretty sure that once we've created the infrastructure to support bitmap > filters on a Canvas, its easy to implement more Flash filters if needed. I > would start with the ColorMatrix filters since its the most used and also a > lot of other filter effects can be archived with the same effect using a > ColorMatrix. > > What do you think? Is it worth it to talk to the gfx guys during the work > week? > > > Tobias > _______________________________________________ dev-platform mailing list [email protected] https://lists.mozilla.org/listinfo/dev-platform
