Appearance
Meshes, the materials on them, the paint the player picks, and the lamps. This is where most of a reskin happens.
01. Mesh slots
The Meshes section lists every mesh slot the vehicle has. A slot is a fixed hole in the vehicle's structure - you replace what fills it, you do not add new ones.
Slots are grouped by the prefix before the first underscore, so
Door_Driver and Door_Passenger0 both sit under Door. Use the
diagram at the top of the section to jump to a body area. Switching to
another group clears the part you had picked and selects the whole
vehicle.
Hierarchy, pinned at the top of the panel, shows how the slots are
attached to each other, so you can tell which part a mirror or a handle
hangs off. It stays in place while the list below scrolls. Pick a node
to select it in the preview and scroll the list to it; pick the vehicle
at the top of the tree to select the whole vehicle and return to the top
of the list. Selecting the whole vehicle in the Details panel does the
same. A node marked @SocketName is attached to a socket rather than
directly to its parent.
The list under the tree nests the same way: a child slot sits indented
under its parent, in its own colour, labelled in <parent>. Selecting a
part in the preview highlights it in the tree and scrolls the list to it,
switching to its group if another group is shown.
For each slot you can set the mesh asset and its relative transform.
Leaving a mesh empty does not bring the original back - it writes None,
which removes that part in game. Use it to delete a part on purpose, not to
undo a change.
Base meshes look empty here, and that is expected.
ModKit does not ship the game's vehicle art. Untouched slots therefore show as None in the panel and render nothing in the preview, but they still use the original mesh in game. Import your own mesh to see something.
02. Preparing an FBX
The rules are the same as for Build objects, so that guide is the fuller reference. The short version:
| Item | Setting |
|---|---|
| Scale | 1 unit = 1 cm |
| Nanite | Enabled |
| Mesh type | Static mesh |
| Origin | Match the slot's original pivot, or expect to correct it with the slot transform |
⚠️ Exporters from Blender, Maya and 3ds Max often drop UV2 unless you explicitly include it.
Importing
- Open Meshes and find the slot you want to change.
- Click Import on the slot's mesh field and pick your FBX.
- If the FBX contains more than 200,000 vertices, ModKit shows its mesh statistics and asks whether to continue. The triangle count is an estimate from the FBX polygon data.
- Check the import settings - Nanite on, materials reassigned by hand rather than auto-generated.
- The slot now points at your asset and renders in the preview.
You can also import first and select the asset afterwards, which is easier when one FBX feeds several slots.
03. Fitting the new mesh
A mesh swap changes what is drawn and nothing else. Three things stay where they were and may need a manual pass:
| What | Why it matters | Where to fix it |
|---|---|---|
| Bounds | The placement and collision box does not resize itself. | Bounds & Audio |
| The distant mesh | The simplified body is separate from the slots. | General |
| Slots and seats | Seats, interaction points and carried objects sit where the original body put them. | Slots, Objects |
Small visual mismatches are normal and not worth chasing: wheel spin speed against a new wheel radius, a head light sitting slightly off its housing. Note them in your mod description instead.
04. Materials
The Materials section, right under Meshes, has buttons to create materials for the vehicle. Two types are available:
| Type | Based on | Use it for |
|---|---|---|
| CarPaint | The car-paint master material | Body panels. This is the material that receives the player's chosen paint colour. |
| Prop | The shared prop master | Everything that is not painted: trim, glass housings, interior. |
Created materials land in your plugin's Materials folder. Open
Folder below the buttons shows that folder in the Content Browser.
Below the buttons, every mesh slot that has a mesh is listed with the material in each of its material slots. A slot marked Override uses its own material instead of the mesh's, so changing the material inside the mesh asset does not show there. Pick another material to override a slot, click the reset arrow to go back to the mesh's material, or click the edit icon to open the material in its editor. When the material belongs to your mod, Textures under the slot lets you import or reimport its textures.
Texture conventions - which maps go in which channel, compression settings, sRGB, virtual texture streaming - are shared with Build objects and documented in the Build guide.
Assigning a material to a slot is done in the panel, in Materials. The generic "assign material" tooling does not apply to vehicles.
05. Paint colours
Paint is a list of colours the player chooses between. Each entry is an sRGB hex value plus an optional icon.
- The first colour is the Representative Colour. It is edited in General, doubles as the thumbnail, and cannot be deleted - see General.
- Everything after it is a colour variant, listed in Paint, and you can add and remove them freely.
Which parts actually change colour
Only materials that expose a Paint Var Tex parameter get repainted. That is why chrome trim and glass keep their own look while the body changes. If you author a body material and the paint does nothing, it is almost always because the material is a Prop material rather than a CarPaint one.
Checking a colour before you commit
Each colour row has a Preview button that applies it to the paintable materials in the viewport. A Reset Color Preview button at the top of the section puts everything back.
06. Lights
Each light slot exposes three values:
| Value | What it does |
|---|---|
| Light Colour | The colour of the lamp. |
| Intensity | How bright it is. |
| Attenuation Radius | How far the light reaches. |
The slots come with the vehicle, so this is tuning rather than authoring - you cannot add a new lamp. If your new body puts the head lights somewhere else, move the light slot's transform to match.
07. Common issues and fixes
| Issue | Cause | Fix |
|---|---|---|
| Slot shows None and renders nothing | Original vehicle art is not shipped with ModKit | Expected. Import your own mesh to see it |
| Paint colour does nothing on the body | Body material is a Prop material, or lacks Paint Var Tex | Author the body with a CarPaint material |
| New mesh is the wrong size or floats | Export scale, or a different pivot | Re-export at 1 unit = 1 cm, or correct the slot transform |
| Mesh looks right, vehicle blocks placement oddly | Bounds still describe the old body | Update Bounds |
| Colour preview left the viewport wrong | A preview colour is still applied | Click Reset Color Preview |
| Material assigned but nothing changed | Assigned outside the panel | Set the material override on the slot in Meshes |
08. Chapter summary
| Checklist | Done |
|---|---|
| Exported at 1 unit = 1 cm with Nanite on? | ✅ |
| Body panels using a CarPaint material? | ✅ |
| Slot transforms corrected after the swap? | ✅ |
| Light positions still on the housings? | ✅ |
| Bounds and the distant mesh updated? | ✅ |
09. What the MCP tools cover
| Tool | Use |
|---|---|
modkit_list_vehicle_components | Call first. Returns every slot, light and colour name you need below. |
modkit_import_mesh | Import an FBX into the plugin and get its asset path. |
modkit_set_vehicle_mesh | Replace a slot's mesh; empty clears the slot (the part disappears in game). |
modkit_set_vehicle_transform | Move, rotate or scale a mesh slot. |
modkit_set_vehicle_light | Colour, intensity, attenuation radius. |
modkit_set_vehicle_color | Add or update a paint variant. |
modkit_create_material / modkit_set_material_texture | Author CarPaint and Prop materials. |
Assigning a material to a slot is editor-only.
10. Data reference
- Vehicle - where the colour list lives.
- FB1VehicleColorData - one paint entry: colour id, UI hex, in-game blend.
- ObjectBP - the component data behind mesh slots and lights.
- ColorMapping - the colour ids a paint entry refers to.