One kind of layer that would not have premultiplied alpha would be a
CanvasLayer with a WebGL context with the {premultipliedAlpha:false}
context attribute (what was passed as the 2nd argument to
canvas.getContext).I did some testing and found a bug, https://bugzilla.mozilla.org/show_bug.cgi?id=924375 . But I don't know whether it's related to what's discussed here. Benoit 2013/10/8 Robert O'Callahan <rob...@ocallahan.org> > On Mon, Oct 7, 2013 at 3:11 PM, Chris Peterson <cpeter...@mozilla.com > >wrote: > > > I stumbled upon some layout code that for transparent colors using != or > > == NS_RGBA(0,0,0,0): > > > > http://dxr.mozilla.org/**mozilla-central/search?q=** > > regexp%3A%23[!%3D]%3D%20%3FNS_**RGBA%23< > http://dxr.mozilla.org/mozilla-central/search?q=regexp%3A%23[!%3D]%3D%20%3FNS_RGBA%23 > > > > > > Are those checks unnecessarily restrictive? > > > > One of the checks has a comment saying "Use the strictest match for > > 'transparent' so we do correct round-tripping of all other rgba() > values", > > but the strictness of the other checks is unclear. ;) > > > > All those checks look correct to me. Most of the colors we deal with are > using premultiplied alpha (e.g. the checks in nsDisplayList certainly do), > in which case the only valid alpha value is RGBA(0,0,0,0). > > Rob > -- > Jtehsauts tshaei dS,o n" Wohfy Mdaon yhoaus eanuttehrotraiitny eovni > le atrhtohu gthot sf oirng iyvoeu rs ihnesa.r"t sS?o Whhei csha iids teoa > stiheer :p atroa lsyazye,d 'mYaonu,r "sGients uapr,e tfaokreg iyvoeunr, > 'm aotr atnod sgaoy ,h o'mGee.t" uTph eann dt hwea lmka'n? gBoutt uIp > waanndt wyeonut thoo mken.o w * > * > _______________________________________________ > dev-platform mailing list > dev-platform@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-platform > _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
