Comment 4 for bug 1597290

My branch updating the default wallpaper [1] makes this a little better. With that MP, the only blurry wallpapers are portrait-wallpapers-on-a-landscape-screen (i.e. it fixes the most common case: landscape-wallpapers).

The proper fix is a little tricky. We can either (A) load a lot more of the wallpaper than we might need -- which slows loading down a bit and is wasteful of memory -- or (B) test-load the wallpaper first to see it's aspect ratio and adjust how we scale it to avoid the double-scaling we currently see on portrait wallpapers. (B) is complicated by the fact that it would involve changing the sourceSize of the CrossFadeImage object holding the wallpaper, which currently makes the CrossFadeImage go to black. Which kind of defeats the purpose of CrossFadeImage. So we may need some toolkit work.

[1] https://code.launchpad.net/~mterry/unity8/default-wallpaper/+merge/297636