3D car models for games: generate, import and drive

Parked car or drivable car?

Decide first, because the work is very different.

• Parked or background cars (traffic, set dressing, wrecks): a single mesh with a box collider is enough. Generate it, scale it, drop it in.
• Drivable cars: the wheels must be separate objects that spin and steer, the body needs a sensible collider, and the pivot set-up has to match the engine's vehicle system.

AI generators, Vi3W included, produce one mesh per generation. A parked car is done after generation. A drivable car needs the steps below.

Step 1: Generate the body

A side-view sketch is the most reliable input for a car, because the profile carries most of the design. Sketch to 3D car covers how to draw it so the wheels and glass read correctly. Describe the type and materials: "compact hatchback, matte blue paint, black wheels".

Check that the wheels are round, aligned and evenly sized, and that the car is symmetrical from above.

Step 2: Separate the wheels in Blender

1. Import the GLB or FBX into Blender.
2. In Edit Mode, select one wheel. Hover over it and press L to select linked geometry if the wheel is a separate island; otherwise select it with box select in side view.
3. Press P › Selection to separate it into its own object.
4. Repeat for all four wheels.
5. If a wheel is fused into the body (no gap), you'll need to cut it out and fill the hole in the arch. On a background car, skip this. On a hero car, it's sometimes faster to model simple wheels and keep the generated body.

Step 3: Set pivots

• Wheels: pivot at the exact centre of the hub, so they spin in place. Select the wheel, Object › Set Origin › Origin to Geometry works for a symmetric wheel.
• Body: pivot at ground level, centred, or wherever your vehicle system expects it.
• Orientation: make the car face the engine's forward axis, consistently for every vehicle.

Fix a pivot point has more detail.

Step 4: Scale and export

Scale to real size (a compact car is roughly 4 m long), apply transforms (Ctrl+A › All Transforms), and parent the wheels to the body with clear names: wheel_FL, wheel_FR, wheel_RL, wheel_RR.

Export FBX for Unity and Unreal, GLB for Godot.

Step 5: Set up in the engine

• Unity: a Rigidbody on the body, a simple BoxCollider (or a convex mesh collider), and WheelCollider components on empty objects at each wheel position. The visual wheel meshes follow the WheelColliders in script.
• Unreal Engine 5: the Chaos Vehicles plugin expects a skeletal mesh with wheel bones, so you'll rig the body and wheels with simple bones in Blender before export. Follow Epic's vehicle set-up docs.
• Godot 4: a VehicleBody3D with VehicleWheel3D children, each holding a wheel mesh.

For collision on the body, keep it simple. A box or a few boxes beat a mesh collider for physics stability. Adding collision compares the options.

Triangle budget

Cars are big, so they're often given generous budgets. But traffic scenes multiply fast: twenty cars on screen add up. Use the generated (already retopologised) mesh for mid-distance traffic, add LODs, and reserve detailed models for the player's car.

A shortcut for prototypes

For a jam or prototype, generate the body, use cylinders as wheels, and get driving working first. Swap in the separated generated wheels later. The feel of the car matters more than its rims.

Need a garage of background cars? Generate them in Vi3W and keep your modelling time for the one the player drives.