why can't assetbundle named "abc.bytes"?

[lzqlawrence]

i name my assetbundles "xxx.bytes", It shows me an error "A Play-delivered AssetBundle's name must start with an English letter and can only contain letters, numbers, and underscores. Please regenerate the AssetBundle with a new name.". I am not quite understand.. so many resources named with postfix ".bytes". why can't use postfix ".bytes"?

[jamcohen]

The Asset Delivery Settings... menu wraps the AssetBundle in an asset pack with the same name as the AssetBundle. Because asset packs have the naming restrictions you mentioned, your AssetBundle cannot include the . character.

If for whatever reason you can't remove the postfix from you AssetBundle, there is an API that you can use to package those AssetBundles in an asset pack with a different name. However, you would need to use the experimental method RetrieveAssetPackAsync() to download it.

If you want to give it a try, you can enable the PLAY_ASSET_DELIVERY_EXPERIMENTAL preprocessor definition in player settings (see the "Platform custom #defines" section here for how to do that)

[lzqlawrence]

@jamcohen thanks for your answer.

I have tried to use new API to package my AssetBundles which include . character, and that works.

But I have another question. When I extract the aab, I found that there is just one apk in /asset-slices directory named xxx-master.apk. So, that means if I use new API , all the AssetBundles(ASTC, ETC2, Default) will package into one apk(xxx-master.apk)? Is that means when the user install the App, all the assets will be downloaded?
thanks

[lzqlawrence]

Here is my PlayAssetPackConfig.json:
{ "assetPacks":[ { "name":"aaa", "path":"I:/myUnityWorkspace/TestAAB/Assets/AssetBundles#tcf_etc2", "deliveryMode":"InstallTime" }, { "name":"aaa", "path":"I:/myUnityWorkspace/TestAAB/Assets/AssetBundles#tcf_astc", "deliveryMode":"InstallTime" }, { "name":"aaa", "path":"I:/myUnityWorkspace/TestAAB/Assets/AssetBundles#tcf_default", "deliveryMode":"InstallTime" }], "assetBundles":[ ], "defaultTextureCompressionFormat":"Default" }

[4ian]

Hi @lzqlawrence, for now assetPacks are not supporting targeting by Texture Compression Format, which means that even with the name finishing by a suffix like #tcf_etc2, it won't be recognised in the AAB as asset packs targeted by texture format.

You can see in the documentation of AssetPackConfig that AddAssetBundles can be used to package a set of AssetBundles, one for each texture compression format (compressionFormatToAssetBundleFilePath parameter). This corresponds to the field assetBundles in the PlayAssetPackConfig.json. If you use AddAssetBundles api and serialize the configuration, you'll see that assetBundles will be serialized with a textureCompressionFormat property.

Unfortunately, AddAssetsFolder, which is used to add raw asset packs not tied to an asset bundle, and which is serialized to the field assetPacks in PlayAssetPackConfig.json, does not have support for Texture Compression Format targeting.

This is because Texture Compression Format targeting is still in preview and was built with AssetBundles in mind only. We would need to update the APIs to allow AddAssetsFolder/assetPacks to allow the same targeting.

[lzqlawrence]

@4ian Got it. Thanks.

[4ian]

Hi @lzqlawrence, the latest version of the Play Unity Plugins that was just published (1.2) now includes AddAssetsFolders method that you can use to create an asset pack from directories, each directory corresponding to a specific texture compression format.

[lzqlawrence]

@4ian Thanks.