How tracks are installed

If you're contributing track support, here's what happens when a track is activated. For playing with tracks, see Mods and tracks.

Tracks live as mods in the Team Simplified library. Its build hook works through enabled track packages in profile order, emitting a track.add operation for each, with the source library/<id>/track in Team Simplified's addon-data folder. A data addon can list track.add in an assets file too (A track with its own name). Both swofty build and swofty apply activate every track.add before the other database ops. You'll find the code in packages/core/src/activation/.

The track archive

Putting a track's archive in place isn't enough: the game only loads an asset group when its asset manifest (fileList.manifest) lists it. A listed group asset_groups/<path>.assetgroup points to the file 2025_asset_groups/<path>.erp. Your new track's own paths, such as environment_package/tracks/okayama/wep/okayama_common.assetgroup, aren't on that list.

How the build handles this depends on the in-game core. When its features.json has group, the package's <code>.erp is added at its natural path, 2025_asset_groups/environment_package/tracks/<code>/<code>.erp. Then swofty/assets.json registers these groups for it at runtime:

• the main group, asset_groups/environment_package/tracks/<code>/<code>.assetgroup;
• wep/<code>_<variant> for every world in the archive, stand-ins included;
• the 2019 template groups bake/<code>_ao.bake, bake/<code>_light_list.bake, bake/<code>_radiance.bake, probes/config.ddgi and probes/key_2019;
• probes/probes_garage_<nn> for every garage probe set in the archive;
• ai/<vehicle_package>/<team>/<team> for every AI team folder in the archive.

You can enable any number of tracks this way.

Otherwise, the build puts the package's whole <code>.erp into an existing invitational event slot, 2025_asset_groups/ui_package/texture_arrays/invitational_events/event_images/invitational_image_<n>.erp, alongside the slot's own pictures. Your profile's tracks take invitational_image_4, _10, _13 to _18 in order. That leaves room for at most eight enabled tracks.

The build also fills gaps in the archive:

• For each variant world the package lacks (classic, f2_previous, ...), it copies the nearest world the package has as a stand-in.
• It points texture mip paths at environment_package/tracks/<code>/mipmaps/<file> and adds the files from the package's mipmaps/ there.
• It makes room for the F1 2026 grid if the built database's f1_2026 grid list holds more cars than the f1_26_myteam world (with the common world) has grid slots, garages or pit boxes. The layer holding the last grid slot gets copies of the last slot, garage, in-garage spot and pit box. Each copy goes one row or bay beyond the two before it. Without two slots, garages or boxes to work out the spacing from, the build warns you that a Grand Prix there with that many cars crashes.

The database

Table	Change
tracks.Track_<n>	For a new code, copy_slot clones the slot track's row with a new statId. If the code already has a row (bahrain24), it keeps it. Your track_overrides apply here.
tracks.track_resource.TrackResource_<n>	The track's resource row is cloned as swofty_<code>. On the natural route, its group fields use the 2019 template values with [FILENAME] = <code>: iblAssetGroupsRoot is asset_groups/environment_package/tracks/<code>/probes/ and iblKey is key_2019.assetgroup. trackMapAssetGroup names the main group. On the slot route, every asset group points to the track's slot. The track row's track_resource names the cloned row.
Per-track tables: per-race DNFs, pit lane splines and slide settings, practice programmes (2025 and 2026), tyre wear and tyre wear scales, specialist objectives, track trivia, replay hero shots	If your code has no row, it gets a clone of the slot track's row, or the base track's when the slot has none. A new code always needs the per-race DNF row: the game reads it without checking that it exists.
<datasets>.TrackDataSet_<i>.TrackData_<j>	copy_from_track, or copy_slot when the package has no copy_from_track, clones the base track's row and its sub-tables in every dataset that has it; for a new code, the copy is the dataset's last row. The copy's _metadata_, track and TrackNameData_0.file_name become the code. track_data.game_setup.TrackDataSet[_metadata_=f1_2026].TrackData[_metadata_=<code>] selects the copy in the f1_2026 dataset. Your overrides apply here, limited to their datasets.
Content sets' available_tracks	The code is added wherever the base track is listed, putting your track in the Grand Prix track list.
track_data.sorted_track_order	Gets a TrackRef row for the code.

Each clone copies all source-row keys listed in track_tables.json, plus any keys named by your manifest's overrides. The table's _<row>_instancecount_ grows by one.

Some sub-table names in F1_25.exe exist only as strings built on the stack. To collect every name the game-DB readers use, including those stack-built names, use tools/track_keys.py.

Menus

• The build appends flags, previews and splines from ui/images.json as slices to the texture arrays named in overrides.uidb. Every UI archive carrying an array gets the same slices. Your track's TrackTextures rows then name overrides.<list>.<code>.
• The three track-select scenes and the session picture go into invitational_image_2. They're named in ui_dynamic_texture_loading.uidta.
• Your ui/minimap.json becomes an entry in minimap.uidb, in both databases.erp and flow_race.erp. Its textures load from the track's main group, or from its slot on the slot route.

ERS

You won't find your manifest's ers values in the database. They go into per-track TrackSettings entries in the car handling files: every 2026 handling file gets an entry for your code, cloned from the base track's and given your manifest's values. Without an entry, the track still loads, but the cars use their default ERS settings.

Checking a build

swofty build
python3 tools/map_check.py <overlay folder> --game <game folder>

To check for missing keys too, put F1_25.exe in the game folder (or use --exe) and install numpy, pefile and capstone. Then map_check.py also checks that your track's row has every key the game reads on the source row: the slot track's Track row, its track resource, per-track rows and TrackData rows.

You can also run cargo test -p swofty-core --test real_maps to activate the Sepang and Okayama packages in the database from F1_25_DIR and check the row counts and cloned rows.