Before starting with detailed vehicle setup it is recommended to check out Quick Start guide as this page assumes a minimal working setup has been done.
If making an open-world game with a large-scale map (> ~4000 units), the shifting origin is required (not only for this asset, but in general with game engines that use floating point precision). Explanation.
VehicleComponent
is a building block of NWH Vehicle Physics 2.
VehicleController
is a collection of VehicleComponent
s, which includes VehicleModule
s, Effects
and SoundComponent
s - both of which inherit from VehicleComponent
.
VehicleComponent
that is enabled is updated.ManagerVehicleComponent
such as SoundManager
, EffectsManager
, ModuleManager
or Powertrain
also disables the child VehicleComponents
.lodIndex
value is lower than vehicleController.activeLodIndex
it will be enabled, otherwise it will be disabled. lodIndex
to a value less than 0 to ignore LODs.
Each VehicleComponent
has a state bar which is visible in play mode:
This is where the state of the VehicleComponent
can be checked and changed. Note that changing the state through state bar only affects runtime values and will revert after exiting play mode. The state bar is intended for previewing the current state and testing different values during run-time. For persistent state check StateSettings.
Enabled
button is greyed out as the LODs determine if the component will be enabled or disabled.VehicleComponent
on each VehicleController
, a ScriptableObject
StateSettings
was introduced.StateSettings
for each vehicle can be assigned under VehicleController ⇒ Settings tab. StateSettings
on State Settings page.
To change VehicleComponent
state through scripting following can be done:
myVehicleComponent.LodIndex = -1; // IMPORTANT! Setting this to -1 disables the // LODs which otherwise override the enabled/disabled setting. myVehicleComponent.VC_Enable(); myVehicleComponent.VC_Disable();
VehicleComponent
initialization and update functions start with the VC_
prefix to prevent confusion with Unity callbacks, e.g. VC_Initialize
or VC_FixedUpdate
.</wrap>Ensure you use Project Settings ⇒ Player ⇒ Input Handling ⇒ Both, or multiple errors may occur.
The input in NWH Vehicle Physics 2 revolves around InputProvider
s. These scripts obtain user input from different sources such as InputSystem or Rewired (e.g. keypresses, mouse movement, gamepad input, etc.), process it, and pass it on to the vehicles.
Multiple InputProvider
s can coexist, allowing for e.g. MobileVehicleInputProvider
, InputSystemVehicleInputProvider
, and SteeringWheelVehicleInputProvider
to be present simultaneously. Input from all InputProvider
s is combined.
The diagram above illustrates the path from the input source to the vehicle input state:
Auto Set Input
is set to true, the state of the corresponding input for the vehicle in question will be set to the combined value of all inputs.Input > AutoSetInput
set to false, the new input will be discarded. This occurs when the vehicle is inactive or when the input is set by another script (e.g., AI).autoSetInput
is enabled on them.VehicleInputProvider
(for vehicle-related input) or SceneInputProvider
(for scene-related input, such as cameras). Thus, it's best to consider InputProviders as a standardized interface between different input methods and a vehicle.InputProvider
s are divided into VehicleInputProviders and SceneInputProviders. VehicleInputProviders transmit vehicle input (throttle, brakes, etc.), while SceneInputProviders handle scene input (vehicle changing, camera changing, camera movement, and other inputs not directly related to the vehicle). One of each is necessary (e.g., InputSystemVehicleProvider
and InputSystemSceneInputProvider
).InputStates
struct and can be copied from one vehicle to another if needed. For example, this is done when a trailer is connected to a towing vehicle.InputStates
, ensure autoSetInput
is set to false.
Out of the box gamepad bindings are only available for InputSystem.
Name | Type | Keyboard Defaults | Gamepad Defaults | Description |
---|---|---|---|---|
Steering | axis [-1,1] | A/D | Left Stick - Left/Right | Steering. |
Throttle | axis [0,1] | W | Left Stick - Up, Right Trigger | Throttle. |
Brakes | axis [0,1] | S | Left Stick - Down, Left Trigger | Brakes. |
Clutch | axis [0,1] | Manual clutch. 0 for disengaged and 1 for engaged. | ||
Handbrake | axis [0,1] | Space | B (Xbox) / Circle (PS) | |
EngineStartStop | Button | E | ||
ShiftUp | button | R | Right Shoulder | |
ShiftDown | button | F | Left Shoulder | |
ShiftIntoR1 | button | ` | Shift into 1st reverse gear. | |
ShiftIntoN | button | 0 | Shift into neutral. | |
ShiftInto1 | button | 1 | Shift into 1st forward gear. | |
ShiftInto[n] | button | 2,3,4,etc. | Shift into [n]th gear. | |
LowBeamLights | button | L | Y (Xbox) / Triangle (PS) | |
HighBeamLights | button | K | ||
HazardLights | button | J | ||
ExtraLights | button | ; | ||
LeftBlinker | button | Z | ||
RightBlinker | button | X | ||
Horn | button | H | ||
Module Bindings | ||||
FlipOver | button | M | Used for FlipOverModule. | |
Boost | button | Left Shift | A (Xbox) / X (PS) | Used for NOSModule. |
Cruise Control | button | N | Used for CruiseControlModule. | |
TrailerAttachDetach | button | T | X (Xbox) / Square (PS) | Used for Trailer and TrailerHitch modules. |
Name | Type | Keyboard Defaults | Gamepad Defaults | Description |
---|---|---|---|---|
ChangeCamera | button | C | Start | Changes camera. |
CameraRotation | 2D axis | Mouse Delta | Right Stick | Controls camera rotation. |
CameraPanning | 2D axis | Mouse Delta | Right Stick | Controls camera panning. |
CameraRotationModifier | button | Mouse - LMB | Right Stick Press | Enables camera rotation. |
CameraPanningModifier | button | Mouse - RMB | Left Stick Press | Enables camera panning. |
CameraZoom | axis | Mouse - Scroll | D-Pad Up/Down | Camera zoom in/out. |
ChangeVehicle | button | V | Select | Change vehicle or enter/exit vehicle. |
FPSMovement | 2D axis | WASD | Left Stick | Demo FPS controller movement. |
ToggleGUI | button | Tab | Toggles demo scene GUI. |
InputProvider
for handling user input on desktop devices through keyboard and mouse or gamepad.
Since v1.1 InputSystem package is required even if not used. If using the old/classic Unity input set Project Settings ⇒ Player ⇒ Input Handling to Both
and proceed as normal. InputSystem package being present installed will not interfere with old/classic Unity input / InputManager.
When first importing NWH Vehicle Physics 2 the project will be missing required bindings. There are two ways to add those:
[UnityProjectPath]/ProjectSettings/InputManager.asset
file. To do so:To set up InputManager-based input in the scene add the following components to the scene:
Any vehicle that is present in the scene will now receive input from these providers.
When using DS4Windows, InputSystem will detect button presses twice.
Active Input Handling select
Input System Package (New)
or Both
- the latter in case your project still uses UnityEngine.Input
somewhere.InputSystemVehicleInputProvider
and InputSystemSceneInputProvider
to any object in your scene..inputactions
files. Save Asset
must be clicked for the changes to take effect.Since v1.7.1 NWH Vehicle Physics 2 also supports Rewired input.
Rewired Input Manager
to the scene. It already contains the Rewired InputManager
, as well as the RewiredVehicleInputProvider
and RewiredSceneInputProvider
needed for NVP2 control.InputSystemVehicleInputProvider
, InputManagerVehicleInputProvider
, InputSystemSceneInputProvider
and InputManagerSceneInputProvider
scripts from the scene to prevent input duplication. All these can technically be present at the same time but there are no benefits to it and duplicate inputs might happen.MobileVehicleInputProvider
and MobileSceneInputProvider
to the scene.UnityEngine.UI.Button
component and replace it with MobileInputButton
. MobileInputButton
inherits from UnityEngine.UI.Button
and adds hasBeenClicked
and isPressed
fields which are required for Mobile Input Provider
MobileVehicleInputProvider
and MobileSceneInputProvider
inspectors. Empty fields will be ignored.For more info visit SteeringWheelInputProvider page.
Since v1.0 multiple InputProvider
s can be present in the scene, meaning that their input has to be combined to get the final input result. To get the combined input use:
float throttle = InputProvider.CombinedInput(i => i.Throttle()); bool engineStartStop = InputProvider.CombinedInput(i => i.EngineStartStop());
Or to get the input from individual InputProvider
s (say to find out if a button was pressed on a keyboard):
float throttle = InputProvider.Instances[0].Throttle;
Input in each vehicle is stored in InputStates
struct:
myVehicleController.input.states
In case input should not be retrieved from user but from another script - as is the case when AI is used - autoSetInput
should be set to false
. This will disable automatic input fetching from the active InputProvider
.
Input now can be set from any script:
myVehicleController.input.Horizontal = myFloatValue; // Using getter/setter.
myVehicleController.input.states.horizontal = myFloatValue; // Directly accessing states.
When using input generated by code (i.e. AI) it is usually handy to have access to a single axis throttle/brake. This can be done like so:
vehicleController.input.autoSetInput = false; // Tells the vehicle to stop retrieving input values automatically. vehicleController.input.Vertical = 0.5f; //Sets throttle to 0.5f, resets brakes. vehicleController.input.Vertical = -0.5f; //Sets brakes to 0.5f, resets throttle.
vehicleController.input.states.throttle
is equal to vehicleController.input.Throttle
. The latter is just a getter/setter for convenience.
The alternative to this is using the inputModifyCallback
. It is executed just after the input is retrieved by the vehicle and allows modifying the inputs without having to worry about them being overwritten before the end of the frame:
myVehicleController.input.inputModifyCallback.AddListener(MyInputModificationFunction); --- private void MyInputModificationFunction() { vc.input.Handbrake = 1f; // Apply handbrake by overriding the user input. }
If a custom InputProvider
is needed it can easily be written. Custom InputProviders
allow for new input methods or for modifying the existing ones. E.g. if the MobileInputProvider
does not fit the needs of the project a copy of it can be made and modifications done on that copy. That way it will not get overwritten when the asset is updated.
ExampleVehicleInputProvider
and make it inherit from VehicleInputProvider
class:public class ExampleVehicleInputProvider : VehicleInputProvider{}
GetThrottle()
.ToggleGUI()
which are optional and will be ignored if not implemented.false
, 0
or -999
in case of ShiftInto()
method.ExampleVehicleInputProvider
now can be added anywhere in the scene as the included InputSystemVehicleInputProvider
or InputManagerVehicleInputProvider
would be.
Example custom input script is below. Note that to reference NWH.Common.Input the script will either need to be generated inside Scripts > Input folder of the asset or referenced inside the project .asmdef file if the script is placed outside of the VehiclePhysics directory. For more info about assembly definitions check out the Import guide.
using NWH.Common.Input; using UnityEngine; using UnityEngine.InputSystem; /// <summary> /// Example class for handling input. /// </summary> public class CustomVehicleInputProvider : VehicleInputProviderBase { public override void Awake() { base.Awake(); // Your initialization code here (if needed). Just a standard MonoBehaviour Awake(). } public void Update() { // Your Update() code here (if needed). Just a standard MonoBehaviour Update(). } public override Throttle() { // Return your custom value here, example: return 0.5f; // Replace this line with e.g. player.GetAxis("Throttle") for Rewired. } public override Steering() { // Return your custom steering value here. return 0.123f; } // ...and so on. Override the functions that you want to use. If you do not need Clutch() for example, // do not override it. }
Powertrain
in NWH Vehicle Physics 2 is a collection of Powertrain Components such as EngineComponent
, ClutchComponent
, DifferentialComponent
, etc.PowertrainComponents
, except for WheelComponent
which always outputs to WheelController
.EngineComponent
which acts as a power source and Wheel Component
acts as a power sink. The components in-between determine how the power/torque will be transmitted.
The PowertrainComponent
serves as a foundational class for all powertrain components, including EngineComponent
, ClutchComponent
, TransmissionComponent
, and others.
Each PowertrainComponent
possesses the following shared attributes in the Inspector:
Name
- The label assigned to the component. Note that altering the Name
of a component will reset the * * Output
for any components that utilize that component.Inertia
- Represents the inertia of the component. The inertia of each component contributes to the overall system inertia, which determines the difficulty of spinning the component up or down.Output
- Specifies the Powertrain Component
to which torque is forwarded. For certain components, such as * Differential Component
, multiple outputs may be present (e.g., left and right wheel).Keep in mind the following:
name
field of a component resets all the Output
s for other PowertrainComponent
s that rely on that component as an output.Inertia
value will cause the component to spin up more slowly when the same amount of torque is applied.Inertia
of a WheelComponent
is determined by the WheelController
s mass and radius settings.
Always ensure that the Inertia
value is greater than 0!
The engine acts as a source of power/torque and updates the components attached to it recursively with the generated torque.
When using the Electric engine, consider setting the output to the Transmission, bypassing the Clutch, as it is not needed.
Higher engine inertia results in an engine that is harder to stall. The such engine will also take longer to spin up. Typical values:
The power curve represents engine power across its RPM range.
X and Y values are normalized where X (0 to 1) represents RPM as a percentage of Rev Limiter RPM
and Y (0 to 1) represents power as a percentage of Max Power
.
Note that power and torque curves show the exact same data since the power is a function of torque and RPM, so knowing two of the three is enough. Since power curves are usually easier to find, NVP2 uses a power curve instead of a torque curve.
The Idler circuit tries to keep RPM at Idle RPM
when there is no user input. This is done through throttle modulation so it is still possible to stall the engine if stallingEnabled = true
.
Starter spins up the engine to try and reach the RPM at which the power generated by the engine is enough for it to spin by itself and overcome the losses. The amount of torque needed is automatically calculated based on the engine inertia, Power Curve, and the Start Duration value.
When Flying Start is enabled, the engine spins up instantly without running the starter. This is to give an illusion of the engine already having been started when the vehicle is woken up.
Cuts throttle to the engine when RPM reaches Rev Limiter RPM
for a duration of Rev Limiter Cutoff Duration
.
ForcedInduction
is a part of EngineComponent
. It can be used for both turbocharging and supercharging the vehicle. Power Gain Multiplier
adds power on top of the existing Max Power
so the vehicle with 100kW and Power Gain Multiplier
of 1.5 will actually produce 150kW.TurboWhistleComponent
and TurboFlutterComponent
. If forced induction is to be used just for the sound effects Power Gain Multiplier
should be set to 1.
Power modifiers can be used through scripting to modify the power of the engine. These are functions that return a float
which denotes an engine power coefficient. Example:
public float AddBoost() { if(boostIsActive) { return 1.5f; // Increases power for 50%. } } ... myVehicleController.powertrain.engine.powerModifiers.Add(AddBoost);
This is a fictional example. A concrete example can be found inside the TCS module which uses this mechanic to limit power when there is wheel spin.
ClutchComponent
can be bypassed by setting the output of EngineComponent
directly to the desired PowertrainComponent
but this is not recommended as it will cause stalling in most cases.
There are two things to note here: clutch engagement and clutch input. Clutch input controls the engagement through the Engagement Curve and is set either automatically, through user input, or scripting/inspector. It is best to think of the Clutch Input value as the pedal position, and the engagement as the “biting point” of the clutch.
Automatic
sets the clutch engagement based on the input (engine) RPM. engagementRPM
, throttleEngagementOffsetRPM
and engagementRange
.UserInput
type can be used to give control to the user through a gamepad, steering wheel, etc.Clutch
axis - check Input section for more info on setting up axes.Manual
type does not set the clutch value in any way and instead expects to be set externally, either through the inspector or through scripting.Has Torque Converter
is false Slip Torque
is used. Otherwise, the clutch will use Torque Converter Slip Torque
. \\]Slip Torque
will result in grabby clutch.Slip Torque
values can result in torque spikes when the clutch is suddenly released which can impact solver stability in extreme cases.TransmissionComponent
is a mandatory Powertrain
component. It is always third in the Powertrain.Components
list.
The asset uses W/S to select the movement direction by default. To use W/S as throttle/brake exclusively go to Control > Input and tick Swap Input In Reverse
.
gears
list and should be ordered from reverse, then neutral (always 0), then forward gear ratios. Upshift RPM
, Downshift RPM
, Variable Shift Intensity
and Incline Effect Coeff
variables.Target Upshift RPM
and Target Downshift RPM
can be seen under the under the Shifting section of the TransmissionComponent
inspector, during runtime. These values vary depending on the variables mentioned above.IsSequential
makes the transmission be able to shift only one gear up or down at the time. It has the same effect as ticking both Allow Upshift Gear Skipping
and Allow Downshift Gear Skipping
.CVT
(and eCVT) transmissions have variable gearing ratio dependent on load.Shift
delegate inside TransmissionComponent
is used for changing gears.To make shifting more realistic two timers have been added:
Shift Duration
- time Transmission
takes to change from one gear to another. During this time EngineComponent
's throttle is cut off. Works for all transmission types.Post Shift Ban
timer. This field determines minimum time between two shifts. Used to prevent transmission for shifting too often. Only affects automatic transmission types.
Transmission will only shift in automatic mode if all the ticked conditions conditions have been met for Shift Check Cooldown
seconds:
Wheel Spin
- longitudinal slip on all wheels is less than Longitudinal Slip Threshold
(Settings tab)Wheel Skid
- lateral slip on all wheels is less than Lateral Slip Threshold
(Settings tab)Wheel Air
- none of the wheels are in the air.External Shifts Checks Valid
- list of ShiftCheck
delegates. All external shift checks must be valid for transmission to be able to shift.
Transmission gearing profiles were deprecated in favor of a simple gears
list.
DifferentialComponent
is a type of PowertrainComponent
that splits input torque between two or more outputs.
There can be multiple DifferentialComponents
present on one vehicle and one differential can output to other differentials which is useful for 4WD setup with center differential.
Unused differentials should be removed. E.g. a front differential that none of the other powertrain components (transmission, other differentials, etc.) are outputting to should be removed, as only powertrain components that have a path to Engine are updated.
Torque in open differential is equally split between the left output and right output.
Locked differential keeps both outputs rotating at same angular velocity.
Replaces previous separate ViscousLSD and ClutchLSD options. Torque will be sent to the slower spinning wheel, keeping the wheels locked, up to the slip torque value.
Can be used to assign an external differential delegate function.
To achieve a specific drivetrain configuration, different differential layouts can be used. For example:
WheelComponent
is a PowertrainComponent
. It acts as a torque sink and can not output to another PowertrainComponent
WheelComponent
should not be mixed up with WheelController
or WheelCollider
. WheelComponent
instead interfaces between the powertrain an the wheel.Belongs To
field determines to which WheelGroup the WheelComponent
belongs to. This determines values such as braking, steering and geometry. Inertia
field gets auto-calculated from assigned WheelController
's mass and radius.WheelUAPI
field accepts any wheel controller/collider that uses the WheelUAPI abstract class as its base. The two shipped with the asset are WheelController
and WheelColliderUAPI
. This means that NVP2 can work with any wheel solution as long as it implements WheelUAPI. The reason why WheelUAPI
is not a pure interface is due to the Unity's serialization (or lack of it) for interfaces.Steer Coefficient
determines how much the wheel will steer depending on input. In general cars would have Steer Coefficient
of 1 in front and 0 in the back, except for four wheel steering cars where rear axle usually steers opposite of the front so the value would be negative. Examples: 1
- 100% steering. 0
- no steering.-0.5
- 50% steering in the opposite direction.Add Ackerman
- check this Wikipedia link for more info about Ackerman Steering setup. Brake Coefficient
- amount of brake torque used as a percentage of Brakes
⇒ Max Torque
.Handbrake Coefficient
- amount of brake torque applied when handbrake is activated.Toe Angle
- toe angle in degrees.Caster Angle
- caster angle in degrees.isSolid
being true, as in that case the camber is calculated so that the wheels always stay parallel to each other.
Axle settings are used only if there are exactly two wheels in the WheelGroup
.
Anti Roll Bar Force
- deprecated, Force Application Point Distance
on WheelController
should be used instead. Higher the value, lower the roll.Is Solid
- Imitates solid axle and auto-adjusts camber to make sure that both wheels always stay parallel to each other.
Sound system in NVP2 consists of SoundManager
and multiple SoundComponent
s. Disabling SoundManager
also disables all the SoundComponent
s.
SoundComponent
(type of Vehicle Component
) is responsible for one sound, e.g. EngineRunningComponent
or EngineStartingComponent
.AudioSource
s are not added manually but are instead generated by the script when the scene is started. Some SoundComponent
s can have more than one AudioSource
- e.g. wheel related SoundComponent
s have one AudioSource
for each wheel.VehicleAudioMixer.mixer
) can be used.Mixer
field must have AudioMixer
assigned. By default VehicleAudioMixer
will be used.
SoundComponent
inherits from VehicleComponent
.
Check VehicleComponent page for more info.
SoundManager
is the main class for handling sound. It contains all the global sound settings and also manages individual SoundComponents.
Also check the Sound page.
Master settings affect all the SoundComponent
s
Velocity Magnitude Effect
.Pitch Randomness
field.EngineRunningComponent is a SoundComponent responsible for the engine sound. A pitch based approach using a single pre-recorded engine sound clip is used along with filters to achieve relatively realistic sound.
Big upside of this approach is that only a single clip is required which is ideal for small game studios, as opposed to layering approach where usually tens of clips of engine at different loads, positions and RPMs are used to achieve the engine sound effect. Of course, the downside is that realism suffers.
If you need the layering feature please make a feature request through support.
AudioSource
of EngineRunningComponent
is positioned at Exhaust Position
(Settings tab).Distortion affects volume so when high levels of distortion are used it is usually a good idea to reduce volume range proportionately.
EngineStartStopComponent
plays while the starter is active. AudioSource
of EngineStartComponent
will be positioned at Settings ⇒ Engine Position
.Imitates high-pitched sound of forced induction.
AudioSource
of TurboWhistleComponent
is positioned at Settings ⇒ Engine Position
.Controls all the vehicle effects.
Effect system makes use of VehicleComponents and therefore each Effect
can be turned on or off, be enabled or disable or have LOD set.
Effect
s with manager in the name manage multiple instances of the effect, usually one for each wheel - e.g. skidmarks or surface particles.
ExhaustFlash
Effect
is used to imitate flames shooting out of exhaust. The method to achieve this is identical to the one used for most muzzle flash in FPS games; that is a set of images gets enabled and disabled at rapid rate with different sprite and scale each time. This is a performant way to achieve the effect while avoiding particle effects.
Quad
s perpendicular to each other. Move them to the location of the exhaust.Quad
s.Particles/Standard Unlit
(Unity 2019) or equivalent shader with Transparent
rendering and Multiply
color mode. The included example on Sports Car prefab can be copied. Assigning one of the included flame textures will show if the rotation of the Quad
is correct. Rotate Quad
if needed.MeshRenderer
s from the newly created Quads to the ExhaustFlash
⇒ Mesh Renderers
list.To make flames look more convincing a random texture is assigned to each Quad on each flash. A number of default textures is included.
Flash Textures
list.
ExhaustSmoke
controls exhaust ParticleSystem
color, size and emission speed. It interpolates between NormalColor
and SootColor
based on engine state.
ParticleSystem
s at vehicle exhaust position. Prefab of pre-configured ParticleSystem
comes with the asset (Effects > Particles > Prefabs).ParticleSystem
s to the Particle Systems
list inside ExhaustSmoke
inspector.Skidmarks are generated when wheel skids / slips over a surface.
Max Marks Per Section * 2
. Min Distance
is the distance a wheel needs to travel before a new mark is created.Max Marks Per Section
- similar to the old snake game. To make this transition smooth Fade Over Distance
can be enabled or Peristent Skidmarks
can be used. Check the section below for more info.GrounOffset
needs to be increased.Longitudinal Slip Threshold
and Lateral Slip Threshold
from vehicle settings tab are used.SurfacePreset
to get the settings for the current surface type.
SurfaceParticleManager
creates and manages particles based on current SurfacePreset
settings.
ParticleSystems
.Lateral Slip Threshold
and Longitudinal Slip Threshold
under Settings tab determine the lowest wheel slip threshold needed for wheel to be considered to be slipping. This affects particle effects.
Mirrors are set up through a combination of Camera
s, RenderTexture
s and Material
s with specific UV mapping.
Camera first renders its view to a RenderTexture
which is assigned to a Material
(any shader that supports albedo map will work). This Material
has an UV map that corresponds to the surface of the vehicle mirror.
Possible setups are:
Camera
to a separate RenderTexture
which is assigned to a separate Material
. Best visual quality but slow.
GroundDetection
is one of the most important aspects of NWH Vehicle Physics. It determines which WheelFrictionPreset
will be used for calculating friction, which effects will be active, and which sounds will play. In short, it determines which wheel is on which surface.Terrain
texture indices and object tags so it is very important how many textures there are assigned to the Terrain
and in which order.
To prevent having to change the settings across all the vehicles GroundDetectionPreset
ScriptableObject
was introduced in NWH Vehicle Physics 2.
Terrain
s in one scene.GroundDetection
runs checks for a maximum of one wheel at a time. This is to improve on performance but it can introduce a small delay from the time the surface has been changed to the time GroundDetection
registers it.SurfaceMap
tells GroundDetection
which SurfacePreset
to use for which terrain texture and/or object tag.GroundDetection
runs a check for each WheelComponent
to determine which surface that WheelComponent
is on. This is done by checking all the assigned SurfaceMap
s in order and if any SurfaceMap
has a matching terrain texture index in Terrain Texture Indices
list, or the object the wheel is on has the tag from Tags
list, Surface Preset
will be assigned to that WheelComponent
.
Adding a gravel SurfaceMap
will be used as an example.
SurfaceMap
by clicking on +
button on the bottom of the list.Terrain Texture Indices
list.GravelRoad
) to those objects and add it to Tags
list.
SurfacePreset
tells the VehicleController
which settings to use for which surface.
This determines tire friction, the look of effects such as skidmarks and particle effects. It also changes sounds to match the surface.
Once set up, SurfacePreset
can be used for different terrains, scenes or even across games since SurfacePresets
do not carry any scene-specific fields.
Create ⇒ NWH Vehicle Physics ⇒ Surface Preset
. This will create a new SurfacePreset
ScriptableObject
in the current directory.Friction Preset
. This is a ScriptableObject
with settings for tire friction so that WheelController
can adjust its behavior according to the surface type. With asset come multiple Friction Preset
s so just pick one of those for now.Skidmark Material
will be used on generated skidmarks while the wheel is on this surface type.Slip Factor
determines if the skidmarks are slip dependent. On soft surfaces such as sand this value should be 0 as the skidmarks/thread-marks should always be visible, no matter the slip. On hard surfaces such as asphalt skidmarks are only visible when there is wheel slip.ParticleType
- Smoke
should be used for hard surfaces (asphalt, concrete), Dust
for dusty surfaces (gravel, sand). The difference between the two is in the way the emission rates are calculated. If Smoke
is selected this will be related to the wheel slip while it will depend on vehicle speed for Dust
.Particle Life Distance
is used to calculate ParticleSystem
's Start Lifetime
. The faster the vehicle is going the shorter the lifetime of the particles will be.Max Particle Emission Rate Over Distance
determines amount of particles emitted over distance of one meter.Max Particle Lifetime
determines the absolute maximum time a particle can be alive. When still this value determines how long the particle lives. When moving Particle Life Distance
is used instead.
Chunk particles represent pieces of dirt, debris, sand or pebbles thrown behind the tire when there is wheel spin.
Depending on speed the lifetime of a a particle is calculated from Max Chunk Lifetime
(when near still) or Chunk Life Distance
(when moving).
SkidSound
and SurfaceSound
settings are used to set WheelSkidComponent
and WheelTireNoiseComponent
SoundComponents values for current surface.
If the vehicle is not steering also check WheelGroup settings. It is most likely that all WheelGroup
s have SteerCoefficient
set to 0 which means no axles will steer.
Maximum Steer Angle
- angle in [deg] that the wheels can achieve. Multiplied by the WheelGroup
SteerCoefficient
to get the final axle steer angle.Use Direct Input
- if ticked the raw input is fetched from the InputProvider
s and not processed in any way (smoothing, etc.).Speed Sensitive Steering Curve
- determines the steer angle coefficient in relation to speed. Useful for limiting steering at higher speeds to prevent spinning out.Maximum Steer Angle
is multiplied to get the final steer angle.Speed Sensitive Smoothing Curve
- determines the smoothing applied to the steering input in relation to vehicle speed.Linearity
- maps the steering input value (X) to the new output value (Y). Useful for making steering less sensitive around center point.Degrees Per Second Limit
- an amount of degrees the steering can be turned in one second. Lower number for heavy machinery (e.g. 80), higher for sports car (e.g. 250). Return To Center
- steering will return to center once the input is released.Tips:
Max Torque
as it might introduce jitter.Smoothing
can be used to make braking more progressive when using binary input.Related:
DamageHandler
deforms the meshes on the vehicle (skinned meshes are not supported due to performance reasons).
Deformation Vertices Per Frame
field. Higher value will result in deformation being completed in less frames while lower value will stretch the deformation over the higher number of frames – and will also cause less frame dropping. It is best to adjust this value to as high as it is possible without causing frame drops. This will depend on the device the final game will run on. Deformation Radius
, Deformation Strength
and Deformation Randomness
all affect how the mesh will be deformed – how far the vertex can be moved from the original position, how much it will be moved for the given deceleration and how random the final result will be. Setting randomness to 0 will cause final mesh to be smooth and setting randomness to a high value will result in noisy looking mesh. Deceleration Threshold
is the minimum deceleration value needed for collision to be registered by DamageHandler
.
NWH Vehicle Physics 2 is a collection of VehicleComponent
s. All aspects of it are a component - sound components, effect components, etc. - they all inherit from VehicleComponent
. The only way that a module is different from an inbuilt component is that it can be added or removed as needed.
Modules carry over state system from the VehicleComponent
which means that each module can be turned on or off, enabled or disabled or have LOD set.
VehicleController
.ModuleWrapper
. This is a way to work around lack of multiple inheritance in C#. So, to add a module just add its wrapper to the vehicle:
ModuleManager
is a VehicleComponent
that manages VehicleModule
s.
For more info on Modules check Modules page.
Each module is wrapped in a MonoBehaviour wrapper called ModuleWrapper
. This is a way to get around lack of multiple inhertance in C#.
VehicleModule
inherits from VehicleComponent
, but it also needs to be serialized and for that it needs to be a MonoBehaviour
. The new attribute [SerializeReference] has been present in Unity since 2019.3 and original implementation used that but the amount of bugs and lack of backwards-compatibility with older versions of Unity resulted in the wrappers being used instead.
Adding modules after vehicle initialization is not supported! Consider adding the module before entering play mode or immediately after adding the VehicleController (from scripting), and keeping them Disabled until needed.
To add a module use:
myVehicleController.gameObject.AddComponent<MyModuleWrapper>();
Example (adding an ABSModule):
myVehicleController.gameObject.AddComponent<ABSModuleWrapper>();
Modules are VehicleComponents wrapped in MonoBehaviour containers (wrappers).
MyModule module = myVehicleController.GetComponent<MyModuleWrapper>().module as MyModule;
To remove a module use:
Destroy(myVehicleController.GetComponent<MyModuleWrapper>());
If doing this during the runtime the module should simply be disabled instead. ModuleManager does not update the modules list during the runtime so removing the module will result in an error.
Since modules inherits from VehicleComponent they also work on the same principle:
myModule.VC_Enable();
myModule.VC_Disable();
Note that disabling or enabling a module will have no effect while LODs are active for that module as the LOD system will override the manual settings while active.
To disable LODs for a module use:
myModule.LodIndex = -1;
Scripts ⇒ Vehicle ⇒ Modules ⇒ ModuleTemplate
folder there is an empty example module. Copy ModuleTemplate
to create a starting point for a new module.ModuleDrawer
(a type of CustomPropertyDrawer
) placed in Editor
folder.ModuleWrapper
ModuleDrawer
which uses NUI editor GUI framework (developed by NWH coding) to render custom property drawers and editors through simplified syntax. This also makes the created module compatible with ModuleManager
drawer. Frontal Cd
and Side Cd
(Cd = coefficient of drag) fields. Data for different vehicles is available here.Downforce is calculated in a simplified fashion by applying downforce to a number of points over the vehicle. In the simplest form a single downforce point at the center of the vehicle can be used, or one point at the front and one point at the end of the vehicle.
Downforce Point
s should be below the WheelController
position, or even as low as the floor of the vehicle. This is because all the force is applied in a single point which, if applied too high, can cause the vehicle to snap oversteer when changing direction.Downforce Points
and Max Downforce Speed
.Max Downforce Speed
at which it reaches Max Force
value.Adds additional motorcycle balancing, steering and lean functionality to the NWH Vehicle Physics. The rest of the setup is similar to the conventional vehicle, just with two wheels and transmission outputting directly to the rear wheel, without the use of differentials.
Trikes can be implemented without this module as they do not require the additional functionality.
Field explanations can be seen by hovering over fields in the Unity inspector.
Lean is implemented through a PID controller and is one of the more important settings of the module. It determines in which manner the vehicle will lean and balance. PID controller is required because the balancing is done through physics (AddTorque). The tuning of the said controller requires a bit of tweaking (adjustable at runtime) but the default settings should be adequate for a vast majority of motorcycles.
Module containing a collection of assists aimed at achieving arcade-like behavior from the vehicles. Current functionality:
Adds artificial steer torque to the vehicle, independent of the tire grip. This helps rotate the vehicle.
Prevents the vehicle from drifting over the set angle, effectively preventing spin-outs.
If the vehicle gets flipped over FlipOverModule
will flip it to be right side up again.
Flip Over Activation
determines if the flip over will happen automatically, or if it will wait for user FlipOver
input once it detects that the vehicle is flipped over.Flip Over Type
determines if the vehicle will get slowly rolled over or instantly flipped over in place.
Module for simulating the fuel system in a vehicle. Fuel consumption gets automatically generated from engine efficiency (average ICE efficiency is used) and fuel energy content. Consumption can be adjusted through Consumption Multiplier
.
Amount
indicates the amount of fuel currently in the tank while Capacity
indicates maximum tank capacity.
TrailerModule
works in tandem with TrailerHitchModule
. VehicleController
that has TrailerModule
is able attach to a VehicleController
that has TrailerHitchModule
.
TrailerHitchModule
and TrailerModule
.Attachment Point
is the point at which the trailer will be attached to the towing vehicle. The script creates a SphereCollider trigger at this point which detects if the TrailerHitchModule Attachment Point
is nearby. Attachment Point
needs to be a child of the GameObject
containing the TrailerModule
.Trailer Stand
is the object which will be enabled if the trailer is detached and vice versa. It prevents the trailer from tipping forward on trailers with only the back axle.Synchronize Gear Shifts
is enabled the trailer object will be kept in the same gear. This allows for powered trailer or vehicles that are constructed out of two Rigidbodies.Also check Trailer Hitch module.
VehicleController
with TrailerHitchModule
can attach a VehicleController
with TrailerModule
as a trailer.
TrailerHitchModule
and TrailerModule
can be present on one vehicle at the same time.AttachmentPoint
is the point at which the trailer will be attached. The trailer will be moved so that both trailer and hitch AttachmentPoint
s are at the same position. This is where the physics joint gets created. Attachment Point
needs to be a child of the GameObject
containing the TrailerHitchModule
.TrailerModule
and TrailerHitchModule
triggers, pressing 'T' (default key mapping) will connect the trailer.Also check Trailer module.