Configure your own vehicle
Goal: make a four-wheel vehicle model into a vehicle that you can drive with RCCP. Then save the vehicle as a prefab.
Before you start
Complete Your First Drive. Use a copy of your scene for this tutorial. Stop Play Mode before you edit.
Use a model with a separate body and four separate wheel objects on two axles. Expand the model in the Hierarchy. Select each wheel and make sure that Unity selects only that wheel.
| Model check | Reason |
|---|---|
| Four separate wheel objects on two axles | The wizard assigns front left, front right, rear left and rear right. |
| The body faces local +Z, with its right side along +X | The wizard uses these directions to find the four corners. A reversed body can reverse the assignments. |
| Local Y points up, and the vehicle root stands upright along world Y | Correct a root with Z up before the setup. |
| Wheel axles are along local X | Automatic wheel detection uses this orientation. |
| The model has its real size in meters | Examine the model size on Basic Settings. If the dimensions are wrong, correct them before you continue. |
| Each wheel pivot is at the wheel center, if possible | A pivot at the center gives the wheel a correct rotation center. |
If the wheels are part of the body mesh, separate them in your modeling software first. A new object name does not separate a mesh.
The wizard supports four wheels on two axles. A model with merged wheels or a bike needs a different model or a manual setup. Configure extra axles manually after the setup. See Optional: configure a vehicle manually.
1. Put the model in your scene
- Find your model in the Project window.
- Drag the model into the Hierarchy. Unity creates an instance in the scene.
- Select the top-level object of the model. This object is the parent of the body and all four wheels. This object is the vehicle root.
- Open Tools > BoneCracker Games > Realistic Car Controller Pro 2 > Vehicle Setup > Setup Wizard.
Check: the Target Vehicle field of the wizard shows your scene object. A model that you select only in the Project window is not a valid target. If the vehicle already has an RCCP controller, do not use the wizard again. Edit the vehicle directly.
2. Set the basic vehicle information
On Basic Settings:
- Give the vehicle a name that you can recognize.
- Enter an approximate mass in kilograms. The wizard uses the mass to calculate suggested suspension and engine values.
- Read the model size and the orientation warnings.
- Start with the Balanced handling type. Keep the Stability module, because the handling type needs it.
- If the model is a prefab instance, select its outermost instance root. To change the hierarchy, use the unpack option. If you convert a vehicle from a different setup, use the options that remove old Rigidbodies and WheelColliders.
- Examine Fix pivot position. The option is enabled by default. The option creates a new parent at the center of the model bounds and does not change the mesh. If the origin of the model is already correct, disable the option.
- Click Next.
Check: the wizard accepts the target and opens Wheel Assignment.
3. Assign the four wheels
The wizard tries to find the wheels automatically.
- Examine the four slots as the driver sees the vehicle. FL is front left, FR is front right, RL is rear left, and RR is rear right.
- If a slot is empty or not correct, drag the correct wheel object from the Hierarchy into the slot.
- If the left and right wheels of a pair are in the wrong slots, click Swap L ↔ R. To start the detection again, click Re-detect Wheels.
- Start with the Balanced wheel type.
- Click Next.
Check: the four slots contain four different wheels at the correct corners. Examine the green circles and the forward arrow in the Scene view. The arrow must point to the front of the vehicle.
Detection uses the mesh shape, not the wheel names. If detection does not find a detailed wheel or an unusual mesh, assign the wheel manually.
For a tire and a rim with separate meshes, detection selects their shared wheel parent if its contents fit one wheel. Small hub parts can extend out of the wheel. Detection rejects a parent that also contains body geometry or another wheel. Make sure that each assigned object contains all parts of its wheel.
If wheel parts are next to body objects without a separate wheel parent, detection keeps the individual candidates. Create one parent for the parts of each wheel. Then click Re-detect Wheels or assign those parents manually. Detection does not change the hierarchy. Examine extra candidates before you continue.
For wheel settings, see Wheels and Tires.
4. Keep the first suspension and engine setup simple
On Suspension, start with the suggested values:
- Suspension Distance: the distance that the wheel can move up and down.
- Spring (N/m): the force that holds the vehicle up.
- Damper (N s/m): the force that decreases bounce.
When you first open Suspension and Engine & Drivetrain, the wizard calculates spring, damper and engine torque from the mass. If you change the mass after you open a page, the wizard calculates the values of that page again. Other values do not change. To restore the suggested suspension values, click Recalculate from Mass.
On Engine & Drivetrain, select the Drive Type:
| Drive Type | Wheels that receive engine power |
|---|---|
| FWD | Front wheels |
| RWD | Rear wheels |
| AWD | Front and rear wheels |
Keep the suggested torque, RPM and speed values for your first test. RPM is engine revolutions per minute. Torque is the turning force of the engine.
The wizard sets the gear shift points from Max RPM.
Check: no validation warnings show before you continue. Tune the performance after the vehicle can drive.
5. Choose modules and body colliders
A module is one part of the vehicle, for example its audio or its lights.
On Modules, keep the default selection for the first test. The wizard always adds Inputs and the required drivetrain modules. You can add or remove optional modules later.
Select All selects all optional modules and Headlight Beams, but not AI. If the vehicle needs automatic driving, select AI separately.
Lights adds the light manager without lamps. Headlight Beams needs headlights. After the setup, add the lamps with Tools > BoneCracker Games > Realistic Car Controller Pro 2 > Vehicle Setup > Light Setup. See Lights.
On Body Colliders:
- Make sure that the list selects the body shell and other large solid body parts.
- Keep Convex Colliders enabled.
The list does not include the assigned wheels and their children. The list includes all body parts, whatever their names are.
The Scene view shows the selected parts with an orange overlay. The preview updates when you change a checkbox or click Select All or Select None. The overlay goes away when you leave Body Colliders or close the wizard. The overlay shows the selected source meshes, not the final convex collider shapes.
A collider is the invisible shape that Unity uses for collisions. The body needs its own collider to hit walls and other vehicles.
Check: select at least one applicable body part, or use a body collider that the model already has. Without body colliders, the wizard stops at Finish Setup. Keep Convex Colliders enabled. Finish Setup does not accept selected non-convex MeshColliders, because a moving Rigidbody cannot use them.
6. Finish the scene setup
CAUTION: Stop Play Mode before you finish the setup. Finish Setup stays disabled in Play Mode. Changes that you make in Play Mode are lost when Play Mode stops.
On Finalize:
- Examine the summary. To edit a step, click its summary row. To go back to the summary, click Return to Finalize.
- If the scene has no RCCP camera, click Add RCCP Camera. In the scene of the vehicle, the wizard disables the enabled cameras with the MainCamera tag and their AudioListeners.
- If the scene has no ground collider, click Add Ground Plane. The wizard puts a 2000 × 2000 m plane below the vehicle, with its center under the vehicle.
- If you do not want the dashboard, disable Add UI Canvas. By default, the wizard adds the RCCP UI Canvas.
- Click Finish Setup. Read the dialogs that open.
| Dialog | Action |
|---|---|
| Model Collider Audit | Read the collider problems. If the trigger colliders, wheel-mesh colliders or non-convex body colliders are not intended, click Fix & Continue. The wheel-mesh count includes parts with wheel, tire or rim in their names, and parts such as BrakeCaliper_FL. Fix & Continue removes the trigger and wheel-mesh colliders and makes the non-convex MeshColliders convex. To keep those colliders, click Continue As-Is. |
| Missing Body Collider | Click Choose Body Colliders to go back to that step. Select applicable body parts, then go back to Finalize. The setup does not continue until you add body colliders. |
| Meshes not Readable | If you selected the Damage module, click Enable Automatically to make dents possible. The wizard enables Read/Write on the model assets and reimports them. |
| Scene Not Ready | Click Go Back. Add a camera and a ground before the driving test. |
Check: the vehicle root has an RCCP controller, and the modules are below the root. The wheel components are at the wheel positions.
Read the completion message for the driving controls, the light setup and the validator warnings. Correct the warnings before the first drive.
Finish Setup records the conversion as one Undo operation. Edit > Undo restores the original hierarchy, components and prefab connection. A new pivot parent keeps the original scene, parent and sibling order of the model.
7. Drive, then save the vehicle
- Put the vehicle above the ground. Make sure that the wheels do not touch other objects.
- Click Play and click in the Game view. Test acceleration, steering and braking as in Your First Drive.
- Look at the wheels. Each visible wheel must stay at the correct corner and turn when the vehicle moves.
- Stop Play Mode before you make changes that you want to keep.
- Save the scene.
- Drag the completed vehicle root from the Hierarchy into a folder in the Project window. Unity creates a prefab, a reusable copy of the completed vehicle.
Check: the vehicle drives, and the Project window contains the prefab. Keep the original imported model. The prefab uses the meshes and materials of the model.
If a different vehicle receives the controls or the camera, see Scenes and Spawning to select the player vehicle.
Add and remove modules after setup
Select the vehicle root to see its module cards.
The compact cards use category colors for their outlines. Each group heading uses the same color and has an icon.
Open the screenshot at full size.
Start with the numbered cards. Use 1 Engine to change the engine performance. Use 2 Inputs to change the driving input response. Use 3 Audio to change the vehicle sounds. Scroll down for the other groups. The cards that show depend on the modules on your vehicle.
| Click | Result |
|---|---|
| + on a dim card | Adds the module. |
| The body of an installed card | Selects the module for editing. |
| Power symbol | Enables or disables the module. |
| × that shows when the pointer is on the card | Removes the module. |
| Card with a padlock | A required module. You cannot remove it here. |
The groups are Drivetrain, Control, Behavior, Presentation, Features and Optimization. For example, audio and cameras are in Presentation. Damage is in Features.
Cancel does not change the vehicle or its prefab connection. A confirmed removal keeps the prefab connection, and Edit > Undo reverses it.
Diff can show more than one differential. Its menu lets you select the differential that connects to each axle.
The module bar in the Scene view opens the same cards. See Scene Panels.
The Inspector keeps a separate scroll position for each vehicle in each Inspector window. Select a vehicle again to go back to its last position. A script reload or an Editor restart clears these positions.
Scene Panels
When you select an RCCP vehicle, the Scene view shows its parts and its most-used settings around the vehicle. You can do usual tuning without the Inspector.
Open the screenshot at full size.
| Part | What it does |
|---|---|
| 1 RCCP button | In the Scene view toolbar. Turns Scene Panels on or off. Its arrow holds Part dots and radials, Open Scene Tools panel and Scene Panels documentation. |
| 2 Vehicle chip | Above the car: its name, its behavior preset and its checks. Click the preset to choose one for this vehicle only. Click the checks to see what needs attention, with a fix where one is available. ⋯ has Frame, Select vehicle root, Open Vehicle Settings, Validate now and, with the AI Assistant installed, Open AI Assistant. |
| 3 Part dots | Faint dots mark the parts you can see: engine, axles, lights, exhausts, damage and customizer. Point at a dot and it turns into that part's item right where it sits, with what the part does. The engine dot also lines up the clutch and the gearbox beside it, in the order the power flows; move along the row to pick one. Click the engine or an axle to edit it here, or any other part to select that module. For what you cannot point at, rest the pointer on the car away from the dots: a radial opens with that area's hidden parts, like the center of mass inside the body or an engine on the far side, each with a hollow dot and a dashed line to where it sits, and a dimmed item with + for each of these parts the car does not have yet. Click + to add it. |
| 4 Module bar | Below the car: the six module groups from the vehicle Inspector, with their counts, then Frame, Validate, Vehicle Settings and, with the AI Assistant installed, AI. Click a group to add, select, switch or remove its modules, exactly as on the module cards. |
Dots and the camera. If a dot is under the handle of the Move, Rotate, Scale or Transform tool, the tool handle gets the click. A right, middle or Alt drag that starts on a dot moves the camera. The mouse wheel zooms. With the Hand tool, the dots do not block the pointer, because the Hand tool only moves the camera.
Quick cards. Click the engine or an axle to open a card next to the vehicle. The card shows the most-used settings of that module, the same rows as Vehicle Settings. The engine card also shows the torque curve. A card edit gives the same result as the same edit in the Inspector. This includes the final drive ratio when the engine calculates it.
The card opens where the Scene view has space, and never on the module bar or on the Scene view overlays. When there is not sufficient space, the card rows scroll. To close the card, press Esc or click ×.
Zoom out. The panels get smaller when the vehicle gets smaller on the screen. When the vehicle is small, the dots and radial items get smaller. Radial items show their names only when the pointer is on them. The module bar shows only its group icons and counts. Then ⋯ on the chip has the actions of the bar. When the vehicle is very small, only the chip stays, with Frame to show the vehicle again.
More than one selected object. Scene Panels follow one vehicle: the vehicle that contains the active object. The active object is the object that you clicked last. To move the panels to a different vehicle, Ctrl-click that vehicle (Cmd-click on macOS). If the active object is not part of a vehicle, the panels hide, also when other selected objects are vehicles.
When you select other vehicles too, the chip shows +N, the number of these vehicles. To move the panels, click +N and select a vehicle. The selection does not change.
A card edit or a handle edit changes only the vehicle that has the panels.
Steering and suspension handles. While an axle card is open, each steered wheel shows its real steering range. The inside wheel turns more than the outside wheel. To change Steering angle, drag the round handle on that range. To change Rest position on both wheels, drag the handle on the travel bar next to the wheel. Each drag is one Undo step.
Disable the panels. Click the RCCP button. Unity saves this choice for your user account, not in the project. If the button is not visible, put the pointer on the Scene view and press the ` key. In the overlay menu, enable RCCP.
Check: select your vehicle. The chip, the part dots and the module bar show around the vehicle. When the pointer is on the engine dot, the dot changes into the Engine item. Scene Panels hide in Play Mode and for a disabled vehicle.
The dots, radials and handles need the Gizmos of the Scene view. If Gizmos is off, only the chip and the module bar stay. The dots also hide while a setup wizard is open, or while Edit Light Positions in the Lights editor is on.
Setup troubleshooting
| Symptom | Check |
|---|---|
| The wizard does not accept the model | Select an active scene object in the Hierarchy. The object must not be in an RCCP vehicle already. |
| A wheel is not found, or is at the wrong corner | Assign the wheel manually and examine the forward direction of the model. |
| Each wheel shows two times | The body mesh still contains static wheels. Remove them in the modeling software. |
| The vehicle falls through the ground | Examine the ground collider and the body colliders of the vehicle. |
| The wheels turn but the vehicle moves very little | Examine the scale, the wheel positions and Tuning Recipes. |
| The body does not dent | Enable Read/Write on the source model and see Damage. |
Optional: configure a vehicle manually
Use a manual setup for vehicles that the four-wheel wizard cannot configure, for example unusual axle layouts. Add the RCCP_CarController component to the vehicle root. Then add the drivetrain and other modules with the module cards.
For optional fake headlight beams, use the Lights Inspector. For optional visual tire deformation, use the Axles Inspector. Both panels edit the settings of the effect components directly. The effect components go below their modules, so the vehicle root stays clean.
The wheel solver supports 1 to 8 wheels assigned to the axles of the vehicle. The validator reports a vehicle with more wheels before Play Mode.
Create and put the axles and wheel components in position. Assign the visible wheels, connect each differential to its axle, and add body colliders. For wheel settings, see Wheels and Tires. For drivetrain connections, see How the Car Drives. For a usual four-wheel vehicle, the wizard is faster.
Read next
- Tuning Recipes: correct a specific handling or sound problem.
- How the Car Drives: the engine, the gears and the wheels.
- Assists and Presets: decide if the handling belongs to this vehicle or to a shared preset.