On Tue, 4 Jul 2006 04:18:18 GMT "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> babbled:
> > Jose writes: > > > > > > > correct. non-premul to premul is destructive. VISUALLY it will look > > > the same when composited, BUT this should be an understanding - > > > correct. > > > > > > > Yes, that's right. It destroys the superflous information > > that may be contained in the overdetermined inputs - as far as the > > actual compositing is concerned. > > > I should add that this is also one reason why we want to > work entirely in premul color space - so we don't have to premul > anything, we just assume the inputs to be so and simply use them > as given. > If one instead assumes the inputs to be non-premul, then > one has to, at the compositing stage, premultiply them -- what you > input is not really what gets used for compositing. > > ******************** > > Carsten writes: > > > well actually i was thinking ALL engines would use premul ARGB > > by DEFAULT unless you tell them that you want to get/set pixel > > data in another colorspace (yuv, yuva (planar, interleaved etc.), > > non-premul argb etc. etc.). IF the engine CAN handle the format > > natively (eg some yuv formats if we have xvideo accel) then the > > engine will avoid any conversion internally and deal with it as-is. > > if it cannot - then it will convert as needed internally. > > What engine is going to "handle" non-premul argb "natively"? > That's what evas' software engines do right now, and creates the > inconsistency with the render engine. > You can't perform transforms in non-premul color space and > expect to obtain the same results as similar transforms in premul > color space. > > You are mixing two different kinds of things here - yuv vs rgb > is NOT the same thing as premul vs non-premul. i know - engine are allowed to make approximations though - it is valid :) i am talkign theory here though. *IF* the destination targets can't do rpemul the engine will have to convert to non-premul just like the xrender enigne converts to premul... :) -- ------------- Codito, ergo sum - "I code, therefore I am" -------------- The Rasterman (Carsten Haitzler) [EMAIL PROTECTED] 裸好多 Tokyo, Japan (東京 日本) ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ enlightenment-devel mailing list enlightenment-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/enlightenment-devel
