Public Member Functions | Static Public Member Functions
PhysxWheelShape Class Reference

A special shape used for simulating a car wheel. More...

#include "physxWheelShape.h"

Inheritance diagram for PhysxWheelShape:
PhysxShape PhysxObject PhysxEnums TypedReferenceCount TypedObject ReferenceCount MemoryBase MemoryBase

List of all members.

Public Member Functions

virtual TypeHandle force_init_type ()
float get_axle_speed () const
 Retrieves the current axle rotation speed.
float get_brake_torque () const
 Must be nonnegative.
float get_inverse_wheel_mass () const
 Returns the inverse mass of the wheel.
float get_motor_torque () const
 Retrieves the sum engine torque on the wheel axle.
float get_radius () const
 Returns the radius of the sphere.
float get_steer_angle () const
 Retrieves the steering angle, around shape Y axis.
float get_steer_angle_rad () const
 Retrieves the steering angle, around shape Y axis.
float get_suspension_travel () const
 Returns the suspension travel.
virtual TypeHandle get_type () const
bool get_wheel_flag (PhysxWheelShapeFlag flag) const
 Returns the value of the specified wheel shape flag.
void link (NxShape *shapePtr)
NxShape * ptr () const
void save_to_desc (PhysxWheelShapeDesc &shapeDesc) const
 Saves the state of the shape object to a descriptor.
void set_axle_speed (float speed)
 Set the current axle rotation speed.
void set_brake_torque (float torque)
 Must be nonnegative.
void set_inverse_wheel_mass (float invMass)
 Set the inverse mass of the wheel.
void set_motor_torque (float torque)
 Set the sum engine torque on the wheel axle.
void set_radius (float radius)
 Sets the sphere radius.
void set_steer_angle (float angle)
 Set the steering angle, around shape Y axis.
void set_steer_angle_rad (float angle)
 Set the steering angle, around shape Y axis.
void set_suspension (const PhysxSpringDesc &spring)
 Set the data intended for car wheel suspension effects.
void set_suspension_travel (float travel)
 Set the maximum extension distance of suspension along shape's -Y axis.
void set_wheel_flag (PhysxWheelShapeFlag flag, bool value)
 Turns the specified wheel shape flag on or off.
void unlink ()

Static Public Member Functions

static TypeHandle get_class_type ()
static void init_type ()
 This function is declared non-inline to work around a compiler bug in g++ 2.96.

Detailed Description

A special shape used for simulating a car wheel.

The -Y axis should be directed toward the ground.

A ray is cast from the shape's origin along the -Y axis. When the ray strikes something, and the distance is:

  • less than wheelRadius from the shape origin: a hard contact is created
  • between wheelRadius and (suspensionTravel + wheelRadius): a soft suspension contact is created
  • greater than (suspensionTravel + wheelRadius): no contact is created.

Thus at the point of greatest possible suspension compression the wheel axle will pass through at the shape's origin. At the point greatest suspension extension the wheel axle will be a distance of suspensionTravel from the shape's origin.

The suspension's targetValue is 0 for real cars, which means that the suspension tries to extend all the way. Otherwise one can specify values [0,1] for suspensions which have a spring to pull the wheel up when it is extended too far. 0.5 will then fall halfway along suspensionTravel.

The +Z axis is the 'forward' direction of travel for the wheel. -Z is backwards. The wheel rolls forward when rotating around the positive direction around the X axis.

A positive wheel steering angle corresponds to a positive rotation around the shape's Y axis. (Castor angles are not modeled.)

The coordinate frame of the shape is rigidly fixed on the car.

Definition at line 69 of file physxWheelShape.h.

Member Function Documentation

float PhysxWheelShape::get_axle_speed ( ) const

Retrieves the current axle rotation speed.

Definition at line 267 of file physxWheelShape.cxx.

float PhysxWheelShape::get_brake_torque ( ) const

Must be nonnegative.

Very large values should lock wheel but should be stable.

Definition at line 189 of file physxWheelShape.cxx.

float PhysxWheelShape::get_inverse_wheel_mass ( ) const

Returns the inverse mass of the wheel.

Determines the wheel velocity that wheel torques can achieve.

Definition at line 137 of file physxWheelShape.cxx.

float PhysxWheelShape::get_motor_torque ( ) const

Retrieves the sum engine torque on the wheel axle.

Positive or negative depending on direction

Definition at line 163 of file physxWheelShape.cxx.

float PhysxWheelShape::get_radius ( ) const

Returns the radius of the sphere.

Definition at line 85 of file physxWheelShape.cxx.

float PhysxWheelShape::get_steer_angle ( ) const

Retrieves the steering angle, around shape Y axis.

The steering angle is measured in degrees.

Definition at line 215 of file physxWheelShape.cxx.

float PhysxWheelShape::get_steer_angle_rad ( ) const

Retrieves the steering angle, around shape Y axis.

The steering angle is measured in radians.

Definition at line 241 of file physxWheelShape.cxx.

float PhysxWheelShape::get_suspension_travel ( ) const

Returns the suspension travel.

Definition at line 111 of file physxWheelShape.cxx.

bool PhysxWheelShape::get_wheel_flag ( PhysxWheelShapeFlag  flag) const

Returns the value of the specified wheel shape flag.

Definition at line 300 of file physxWheelShape.cxx.

static void PhysxWheelShape::init_type ( ) [inline, static]

This function is declared non-inline to work around a compiler bug in g++ 2.96.

Making it inline seems to cause problems in the optimizer.

Reimplemented from PhysxShape.

Definition at line 113 of file physxWheelShape.h.

References PhysxShape::init_type().

void PhysxWheelShape::save_to_desc ( PhysxWheelShapeDesc &  shapeDesc) const

Saves the state of the shape object to a descriptor.

Definition at line 61 of file physxWheelShape.cxx.

void PhysxWheelShape::set_axle_speed ( float  speed)

Set the current axle rotation speed.

Note: WSF_axle_speed_override flag must be raised for this to have effect!

Definition at line 255 of file physxWheelShape.cxx.

void PhysxWheelShape::set_brake_torque ( float  torque)

Must be nonnegative.

Very large values should lock wheel but should be stable.

Definition at line 176 of file physxWheelShape.cxx.

void PhysxWheelShape::set_inverse_wheel_mass ( float  invMass)

Set the inverse mass of the wheel.

Determines the wheel velocity that wheel torques can achieve.

Definition at line 124 of file physxWheelShape.cxx.

void PhysxWheelShape::set_motor_torque ( float  torque)

Set the sum engine torque on the wheel axle.

Positive or negative depending on direction

Definition at line 150 of file physxWheelShape.cxx.

void PhysxWheelShape::set_radius ( float  radius)

Sets the sphere radius.

Definition at line 73 of file physxWheelShape.cxx.

void PhysxWheelShape::set_steer_angle ( float  angle)

Set the steering angle, around shape Y axis.

The steering angle is measured in degrees.

Definition at line 202 of file physxWheelShape.cxx.

void PhysxWheelShape::set_steer_angle_rad ( float  angle)

Set the steering angle, around shape Y axis.

The steering angle is measured in radians.

Definition at line 228 of file physxWheelShape.cxx.

void PhysxWheelShape::set_suspension ( const PhysxSpringDesc &  spring)

Set the data intended for car wheel suspension effects.

Definition at line 313 of file physxWheelShape.cxx.

void PhysxWheelShape::set_suspension_travel ( float  travel)

Set the maximum extension distance of suspension along shape's -Y axis.

The minimum extension is always 0.

Definition at line 99 of file physxWheelShape.cxx.

void PhysxWheelShape::set_wheel_flag ( PhysxWheelShapeFlag  flag,
bool  value 
)

Turns the specified wheel shape flag on or off.

Definition at line 279 of file physxWheelShape.cxx.

The documentation for this class was generated from the following files: