Add rotating Adventure battle backgrounds

[vanja-ivancevic]

• Rotates through any number of JPG, JPEG, or PNG battle backgrounds in a folder and avoids immediate repeats when alternatives are available.
• Uses one HTTPS URL in <plane>/skin/battle-backgrounds.txt. That URL points to a plain-text index whose non-comment lines are relative image paths.
• Maps every indexed path in two matching places. For example, enemy/lich/lich_01.jpg is fetched relative to the index URL and stored under <plane cache>/skin/battle_backgrounds/enemy/lich/lich_01.jpg.
• Downloads only missing images when the Adventure plane starts, removes cached images no longer listed, and uses the last valid cached index during temporary host failures.
• Generates stable path-safe folders from canonical point-of-interest names, enemy names, and TMX map paths, so publishing new art normally requires only adding files and index entries on the host.
• Checks folders in this exact priority order, stopping at the first folder containing images: (1) TMX enemy battleBackground, (2) encounter/<poi>/<enemy>, (3) enemy archetype battleBackground, (4) enemy/<enemy>, (5) TMX map battleBackground, (6) map/<poi>/<map>, (7) map/<map>, (8) point-of-interest battleBackground, (9) poi/<poi>, (10) <category>/<biome>, and (11) <category>.
• For each candidate folder, checks the plane cache, local plane files, then common Adventure files. If no rotation folder contains an image, the existing plane, common, current-skin, and default-skin single-image fallbacks remain unchanged.
• Keeps Old Border artwork on the Old Border Shandalar website instead of adding it to the Forge distribution, while leaving the same system available to other Adventure planes and mods.

[tool4ever]

I like the idea, though this adds yet another ~20MB of extra assets to download for every user

Since these seem rather optional imo it's time to think about how they can be downloaded manually like some of the other parts

[vanja-ivancevic]

I agree. If other modders want to add backgrounds, the bloat will continue to increase. Additionally, this is 20MB of data that vanilla Shandalar players won't even use. One approach could be making it optional in the settings via an auto-download feature, handling backgrounds similarly to how we handle card art, like hosting them separately for users to download. Personally, I would like to have them activated by default for Old Border Shandalar, as it enhances the experience. Perhaps when a user switches to and loads that specific adventure mode, the assets could download in the background. Most users likely wouldn't mind an extra 20MB of cached art, especially since we already cache card art this way. Maybe we can have the game download all images in given folders on a server, that way modders can add/remove bgs without updates too… Do you have any preferences?

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On Sat, Jul 25, 2026 at 23:54 tool4ever ***@***.***> wrote: ***@***.**** commented on this pull request. I like the idea, though this adds yet another 20MB of extra assets to download for every user Since these seem rather optional imo it's time to think about how they can be downloaded manually like some of the other parts — Reply to this email directly, view it on GitHub <#11392?email_source=notifications&email_token=ANP6R237OOKGXQLKNDUJEA35GUT7VA5CNFSNUABKM5UWIORPF5TWS5BNNB2WEL2QOVWGYUTFOF2WK43UKJSXM2LFO4XTINZYGAZDOMJTG43KM4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#pullrequestreview-4780271376>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ANP6R27Z5SEK463JWVLPI4T5GUT7VAVCNFSNUABFKJSXA33TNF2G64TZHM2DOOJYHEYDENZSHNEXG43VMU5TIOJXG43TAMBQGU42C5QC> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[tool4ever]

Well some of the lists for the ingame downloaders already point at your domain anyway
so it might make sense to supply them from there
not sure if they can be called via adventure mode but ideally each plane would have its own list with links for its optional assets 🤔
depending on which location you choose some overlap from #11387 is possible

[liminalwarmth]

This is cool, and I would definitely use this feature. If you did package it into the new tabs interface I'm proposing, display would be a logical place to stick it, since there are other settings there that are similar, as tool4forever pointed out.

The tabs definitely become more useful as more GUI options get added, as I'm finding with the additional enhancements I'm doing on local that I haven't pushed upstream until there's more discussion about some of the existing pending changes.

More of an advanced feature, but it would also be neat if plane authors could assign (and distribute) background overrides for specific combat encounters or creature archetypes (if this doesn't already exist).

[vanja-ivancevic]

1. I really like your suggestion of tabbing the settings. We have way too many settings right now in one list.
2. I was thinking about have these custom BGs just as a default setting for the plane's modder to design as they want, with fallbacks in place, as they are sort of a core visual game experience of plane. I don't fully see the need of enabling or disabling more backgrounds. As such, I would suggest to keep it out of settings for now.
3. I 100% agree with your suggestion to have custom BGs for certain POIs and even enemies. I will look into what the best way to do this would be.

[Jetz72]

Still iffy about third party content URLs for assets being included in the main repo. It's not unprecedented, but it's also not unprecedented that such a site proves unsustainable. Ideally we could someday shift to a system where entire Adventure planes can easily be downloaded and installed as complete packages, and then there's no risk of the user getting an incomplete experience. But for now I think this implementation is alright, pending confirmation on iOS handling.

[Jetz72]

@shoeless Will this work with the new iOS support? I saw in that PR that several instances of Gdx.files.absolute got swapped out.

[vanja-ivancevic]

I double-checked this with AI-assisted research against Apple’s filesystem guidance, LibGDX 1.13.5, and Forge’s existing iOS handling. absolute() is supported on iOS and is appropriate for this downloaded cache path, which is outside the read-only app bundle.
The latest revision routes all three lookups through Forge’s existing Assets.getFileHandle() helper. Bundled ASSETS_DIR resources therefore use internal() on iOS, while writable cache paths remain absolute. The iOS compatibility audit also passes. Thanks for flagging this.