Add custom vehicles (addon cars)

Addon vehicles install as a resource that streams the 3D models and their metadata to clients. A bad folder structure or a missing dlctext keeps the cars from showing up in game.

Cause / The problem

Custom vehicles fail to appear when the .rpf is not streamed, the meta files (carcols, carvariations, handling, vehicleslod) are missing or misdeclared, or two packs reuse the same model name. The game then loads a vanilla vehicle or shows a load error.

Solution

1. Create a resource folder, e.g. resources/[cars]/my_cars/, with an fxmanifest.lua:

   fx_version 'cerulean'
   game 'gta5'
   
   files {
       'stream/**/*.yft',
       'stream/**/*.ytd',
       'stream/**/*.meta',
   }
   
   data_file 'VEHICLES_METADATA_FILE' 'stream/**/vehicles.meta'
   data_file 'CARCOLS_FILE'           'stream/**/carcols.meta'
   data_file 'CARVARIATIONS_FILE'     'stream/**/carvariations.meta'
   data_file 'HANDLING_FILE'          'stream/**/handling.meta'
   data_file 'VEHICLE_LAYOUTS_FILE'   'stream/**/vehiclelayouts.meta'

2. Place the models (.rpf, .yft, .ytd) and .meta files inside the stream/ folder. Keep the hierarchy provided by the pack author.
3. Declare the resource in server.cfg:

   ensure my_cars

4. Add the DLC name to a dlctext.meta if the pack requires it, otherwise the model will not be recognized by the spawn menu (/car adder2023).
5. Avoid duplicates: two resources streaming the same vehicle name cause conflicts and FPS drops. Keep only one copy of each model.
6. Restart the server and, on the client side, check the citizen/common/data cache: a clear_cache from txAdmin fixes invisible models after a change.

On the client side, files download automatically on connect. If a car stays invisible, the cause is almost always a missing meta file, not the model itself.