Wallpapers in Windowed Mode are not scaled correctly

[Pablo Marlasca]

When you set a new wallpaper from the Settings App, if it's a landscape wallpaper it will be well scaled if the phone screen is horizontal, but when it's vertical it will look blurry. When the wallpaper is a portrait picture, it happens the opposite: it is well scaled if the screen is vertical but when you rotate it, the wallpaper is blurry. Thanks ;)

[Michael Terry (mterry)]

I'm not sure I quite understand the complaint and/or can't reproduce it.

If the wallpaper is portrait and you are looking at a landscape screen, we scale and crop the wallpaper so that the edges of the wallpaper hit the left and right edge, and crop the top and bottom. Likewise with landscape-wallpaper-on-portrait screen.

So there's some scaling there, which might make it a tad blurry. But not an insane amount, I wouldn't think (and doesn't seem so on my quick tests). Depends on the wallpaper resolution I suppose.

Is there a better thing to do with the wallpaper in that situation?

[Pablo Marlasca (pamarsan1993)]

Yes, I understand that scaling method, but what I mean is that even using a 4K landscape wallpaper, when the phone screen is vertical it looks very blurry (it is not a resolution issue). My phone is a BQ E4.5 (maybe it only happens with this phone model?).

The problem is that the only way of having a sharp background image is when the screen orientation coincides with the picture "format" (portrait or landscape).

I attach a screenshot to show the problem: it is a high resolution landscape wallpaper (2483x1553) that looks blurry when the phone screen is vertical. The Gallery app is open to show that the same picture looks much better in it than in the background. Thanks!!

[Michael Terry (mterry)]

OK cool, will look again tomorrow.

[Michael Terry (mterry)]

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