Tileset not loaded relative to tmx file path

[lea108]

Current bug behaviour

I have created a tmx file map.tmx located in subfolder city_levels. So assets/tiles/city_levels/map1.tmx.

This file references a tileset as a separate file that on disk is located in the same folder (assets/tiles/city_levels/). If I open up map1.tmx I can see that the relative search path is of current folder. So just the name of the tileset file. Let say city_tileset.tsx.

When I do start my game however I get an error that flame_tiled tries to load asstes/tiles/city_tileset.tsx. Eg. it loads the tileset relative to assets/tiles and not relative to the location of the tmx file.

Expected behaviour

The tileset file is loaded using the path in the tmx file relative to the tmx.

Steps to reproduce

Clone this repo https://github.com/lea108/bug_flame_tiled_tilset_path and start the game.

Explanation how it was created:

1. Create a new flutter project
2. Create assets/images/city_levels and assets/tilesets/city_levels folder
3. Create some images and place in assets/images/city_levels/
4. Create a tiled map and save it as map1.tmx in assets/tiles/city_levels/.
5. Create a tileset from the map. Make sure to not check the option to store the tilset inside the map file. Save the tileset to assets/tilesets/city_levels (next to map1.tmx file)
6. In the tileset add the images created in step 3.
7. Save map and tileset.
8. Add the asset folders to pubspec.yaml
9. Add flame and flame_tiled to pubspec.yaml
10. Code a simple game that loads assets/tiles/city_levels/map1.tmx.

Flutter doctor output

[!] Flutter (Channel [user-branch], 3.35.4, on Microsoft Windows [Version 10.0.26100.6725], locale sv-SE) [281ms]
    ! Flutter version 3.35.4 on channel [user-branch] at C:\Users\Lisette\Programmering\Libraries\flutter
      Currently on an unknown channel. Run `flutter channel` to switch to an official channel.
      If that doesn't fix the issue, reinstall Flutter by following instructions at https://flutter.dev/setup.
    ! Upstream repository unknown source is not a standard remote.
      Set environment variable "FLUTTER_GIT_URL" to unknown source to dismiss this error.
    • Framework revision d693b4b9db (3 weeks ago), 2025-09-16 14:27:41 +0000
    • Engine revision c298091351
    • Dart version 3.9.2
    • DevTools version 2.48.0
    • Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios,
      cli-animations, enable-native-assets, enable-lldb-debugging
    • If those were intentional, you can disregard the above warnings; however it is recommended to use "git" directly to perform update      
      checks and upgrades.

[✓] Windows Version (11 Home 64-bit, 24H2, 2009) [4,1s]

[✓] Visual Studio - develop Windows apps (Visual Studio Community 2022 17.14.12) [74ms]
    • Visual Studio at C:\Program Files\Microsoft Visual Studio\2022\Community
    • Visual Studio Community 2022 version 17.14.36408.4
    • Windows 10 SDK version 10.0.26100.0

More environment information

• Tiled version: 3.0.7
• Platform affected: windows (other platforms has not been tested)
• Platform version affected: windows 11

Log information

════════ Exception caught by widgets library ═══════════════════════════════════
The following assertion was thrown building FutureBuilder<void>(dirty, state: _FutureBuilderState<void>#e7040):
Unable to load asset: "assets/images/../../images/city_levels/tile1.png".
The asset does not exist or has empty data.

[spydon]

The path shouldn't be bundled into the the filename argument, the prefix argument should be used when loading from other paths than the root of the cache. Clarified this in an assertion in flame#3747.

[lea108]

The solution is to update onLoad to:

  @override
  Future<void> onLoad() async {
    final map = await TiledComponent.load(
      'map1.tmx',
      Vector2.all(16),
      prefix: 'assets/tiles/city_levels/',
      images: Images(prefix: 'assets/images/city_levels/'),
    );
    world.add(map);
  }```