Configuring App Slicing with Asset Bundles

Unity Engine
, ,
1

I have been trying to configure app thinning to work as follows and have failed so far:

  • iPhone or iPad with less than 2GB of RAM → SD variant
  • iPad with 2GB or more of RAM → HD variant
    static UnityEditor.iOS.Resource[] CollectResources() {
        string manifest = "iOS";
        return new Resource[] {
            new Resource(manifest, "AssetBundles/iOS/"+manifest),
            new Resource("graphics")
                .BindVariant("AssetBundles/iOS/graphics.hd", "hd")
                .BindVariant("AssetBundles/iOS/graphics.sd", "sd"),
        };
    }

Variant slicing configured in Project Settings.

6119252--666659--Screen Shot 2020-07-22 at 16.57.32.png
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The problem I have is that it works fine for iPad with more than 2GB of RAM and for iPhones. But it fails to load anything for iPads with less than 2GB. I would have assumed that “sd” has no requirements so it must be the fallback for the “hd” variant.
Can someone help me configure this correctly?

Edit: Building the project to Xcode I get the following config for “graphics”. As you can see there is a missing reference for the “Any/Any” Slicing.

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2

Following up on my previous post:

It seems that there isn’t anything wrong on the config itself. If I do an export development build I get the following size for an iPad 3 (1GB RAM):

Variant: Unity-iPhone-D980073A-9FF1-4C03-B8F0-2694DBD0BAB3.ipa
Supported variant descriptors: [device: iPad3,3, os-version: 9.0], [device: iPad3,2, os-version: 9.0], [device: iPad3,4, os-version: 9.0], [device: iPad3,6, os-version: 9.0], [device: iPad3,5, os-version: 9.0], and [device: iPad3,1, os-version: 9.0]
App + On Demand Resources size: 96,1 MB compressed, 240,5 MB uncompressed
App size: 96,1 MB compressed, 240,5 MB uncompressed
On Demand Resources size: Zero KB compressed, Zero KB uncompressed

That size is reasonable for SD assets. However, after uploading to iTunes Connect and checking the “Estimated App Store Size” I see the following:

iPad Pro (12.9‑inch) 199 MB (download size) 466 MB (install size)
iPad (3rd generation) 198 MB (download size) 460 MB (install size)
iPhone 11 93.6 MB (download size) 251 MB (install size)

What is also interesting is that for iPad mini (512MB RAM) I have a smaller size meaning its probably using the SD assets.

iPad mini Wi‑Fi + Cellular 130 MB (download) 246 MB (install)

Maybe a bug in the store? Anybody ever faced this issue? Anyways, leaving all these comments in case someone ever bumps on the same issues

EDIT: I’ve emailed Apple dev team to get more insights in what might be happening