hidpi: Background is blurry in HiDPI mode.

[Shaptic]

 * slick-greeter version - 1.2.2
 * Distribution - Arch
 * Graphics hardware *and* driver used - Intel HD620
 * 32 or 64 bit - 64 bit

Issue
I set this image as my background image in slick-greeter. My laptop has a 14" 2560x1440 screen, so I typically need HiDPI options for things to be a usable size. Hence, I set the following in my slick-greeter.conf:

draw-grid=false
enable-hidpi=on
xft-dpi=180

The result was a crisp greeter with appropriately-sized text, but a weirdly-scaled and blurry background. Here is the result in HiDPI mode (as configured above), and here is the result in "normal" mode. Notice how much higher-quality the greeter wallpaper is in the non-HiDPI version.

Steps to reproduce
Just download the image above and run the greeter with this minimal configuration:

[Greeter]
background=/usr/share/backgrounds/mountains-3.jpg
draw-grid=false
enable-hidpi=off

Expected behaviour
I wouldn't expect the background to be scaled in any way (just UI elements), but it is.

[leigh123linux]

Maybe you should update to a supported version, slick-greeter-1.2.2

[Shaptic]

Good suggestion, but no dice. The issue is still present on 1.2.2.

[BradenM]

Issue is still present in 1.2.4. (3000x2000 Display, enabling HiDPI mode "blurs" background picture that is crisp in normal mode)

[Vahan86]

@Shaptic, is this still an issue with slick-greeter 1.3.2?

[Shaptic]

Unfortunately, yes, the visuals are still exactly the same for me after updating through AUR. The background is blurrier in HiDPI mode than in normal mode.

$ slick-greeter -v
slick-greeter 1.3.2

[LSeelig]

I can confirm too. Using 22 at work, and it is fully up to date, but I don't know the slick or lightdm version. Is there any workaround/alternative way to scale that doesn't cause this issue? Does using a higher-res background help? Setting font-name only changed the text at the top, not the login area, and I couldn't tell a difference after setting xft-dpi to 144.