2016-03-14 13:12 GMT+01:00 Matthias Klumpp <matth...@tenstral.net>: > 2016-03-14 12:21 GMT+01:00 Elvis Angelaccio <elvis.angelac...@kdemail.net > >: > > [...] > > Hi! > Thanks for raising this issue! > /me puts his AppStream / Freedesktop hat on > > > 1. Should KDE apps install their app icon even if it's already in breeze? > > From what I understand, icons installed by the apps are used as fallback > if > > breeze is not installed, so that would answer this first question. > > Correct > > > But then why some apps don't install any fallback? > > That is a bug - at time distributors mitigate that by having those > apps depend on the respective KDE icon theme so the applications have > an icon on non-KDE desktop environments too. > There is one exception though: If the app uses a default icon name, > like "system-file-manager", the icon doesn't need to be shipped at all > (more precise: it *must not* be shipped) and the app references the > system default icon. > > See [1] for a list of default icon names which should be present in a > theme. > > This exception is a problem for AppStream, since it means KDE apps > will have a GNOME icon in software stores if they are generic > applications, or vice versa. I am looking for solutions to this > problem, but that's a fringe issue at time. > > [1]: > https://specifications.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html > > > 2. Is enough to install the app icon in .svg (or svgz) format? Why do > some > > app install also 16x16 or 48x48 .png icons? > > 16x16 is likely too small for our modern desktops, for an app icon, so > having it as 48x48 or - as I would recommend - at least 64x64 is the > way to go. Having a 64x64px icon or any bigger size in hicolor ensures > that the app will show up in software stores which are based on > AppStream. > The Freedesktop spec allows any icon size but suggests 48x48px. As > said, I think 64x64 is better at time ^^ > > Installing icons in different sizes decreases the resize overhead > desktop environments have to do, and of course having a bigger icon > prevents DEs from upscaling icons, leading to pixelated icons. > > Toolbar icons should ideally be available in smaller sizes. > > The SVGZ icon format is not allowed by the official specification for > icon formats at all (see [2]), but it seems to be supported by most > DEs now, and maybe we should add it to the specification to formally > allow it (I'll talk to some people). > > Shipping only vector graphics (.svg or .svgz) is something I would > strongly advise against, it's also not really something the icon spec > wants people to do. The main point is that rescaling a bitmap is a > relatively cheap computation, while rendering an SVG image is > expensive. > The rendering result also needs to be cached somewhere and the DE has > to keep a rendering cache for every user, duplicating rendered bitmaps > in the user's home directory and constantly needing to keep the cache > up-to-date. Especially when lots of icons need to be rendered, this > results in a slowdown or icons being available much later when the > desktop environment is started for the first time. > Having low-end hardware (think of mobile phones) render lots of SVG > images by default is also not a great idea. > So, ideally the rendering should happen once to appropriate sizes, > e.g. as part of the applications build process. The additional storage > space needed IMHO outweights the problem of re-rendering SVGs at the > user's side again and again. > > [2]: > https://specifications.freedesktop.org/icon-theme-spec/icon-theme-spec-latest.html#directory_layout > > > 3. Should we update these app icons from Oxygen to Breeze? > > Most likely the answer to that question is yes. >
Hi Matthias, thanks for this very detailed answer. I have one more question though: according to the documentation in [1], the CMake macro ecm_install_icons (which most apps use) does not accept .svg extensions, but only .svgz Shouldn't we edit this macro to also accept .svg icons? [1]: http://api.kde.org/ecm/module/ECMInstallIcons.html > Cheers, > Matthias > > Cheers, Elvis > -- > Debian Developer | Freedesktop-Developer > I welcome VSRE emails. See http://vsre.info/ >
