Unigine::JointHinge Class

 Header: #include Inherits: Joint

This class is used to create hinge joints.

Example

The following code illustrates connection of two bodies (b0 and b1) using a hinge joint.

Source code (C++)
include <UniginePhysics.h>

/* .. */

JointHingePtr joint = JointHinge::create(b0, b1);

// setting joint axis coordinates
joint->setWorldAxis(vec3(1.0f, 0.0f, 0.0f));

// setting common joint constraint parameters
joint->setLinearRestitution(0.4f);
joint->setAngularRestitution(0.4f);
joint->setLinearSoftness(0.4f);
joint->setAngularSoftness(0.4f);

// setting angular damping
joint->setAngularDamping(8.0f);

// setting angular limits, in degrees [-20; 20]
joint->setAngularLimitFrom(-20.0f);
joint->setAngularLimitTo(20.0f);

// setting spring rigidity coefficient
joint->setAngularSpring(8.0f);

// setting number of iterations
joint->setNumIterations(16);

Usage examples:

static JointHingePtr create()

Constructor. Creates a hinge joint with an anchor at the origin of the world coordinates.

static JointHingePtr create(const Ptr<Body> & body0, const Ptr<Body> & body1)

Constructor. Creates a hinge joint connecting two given bodies. An anchor is placed between centers of mass of the bodies.

Arguments

• const Ptr<Body> & body0 - First body to be connected with the joint.
• const Ptr<Body> & body1 - Second body to be connected with the joint.

static JointHingePtr create(const Ptr<Body> & body0, const Ptr<Body> & body1, const Math::Vec3 & anchor, const Math::vec3 & axis)

Constructor. Creates a hinge joint connecting two given bodies with specified axis coordinates and an anchor placed at specified coordinates.

Arguments

• const Ptr<Body> & body0 - First body to be connected with the joint.
• const Ptr<Body> & body1 - Second body to be connected with the joint.
• const Math::Vec3 & anchor - Anchor coordinates.
• const Math::vec3 & axis - Axis coordinates.

Ptr<JointHinge>cast(const Ptr<Joint> & joint)

Casts a JointHinge out of the Joint instance.

Arguments

• const Ptr<Joint> & joint - Joint instance.

JointHinge.

voidsetAngularAngle(float angle)

Sets a target angle of the attached angular spring. The spring tries to rotate the connected bodies so that they make this angle.

Arguments

• float angle - Angle in degrees. The provided value will be saturated in the range [-180; 180].

floatgetAngularAngle()

Returns the target angle of the attached angular spring. The spring tries to rotate the connected bodies so that they make this angle.

Return value

Target angle in degrees.

voidsetAngularDamping(float damping)

Sets an angular damping of the joint.

Arguments

• float damping - Angular damping. If a negative value is provided, 0 will be used instead.

floatgetAngularDamping()

Returns the angular damping of the joint.

Angular damping.

voidsetAngularLimitFrom(float from)

Sets a low rotation limit angle. Rotation limit specifies how much a connected body can rotate around the joint axis.

Arguments

• float from - Angle in degrees. The provided value will be saturated in the range [-180; 180].

floatgetAngularLimitFrom()

Returns the low rotation limit angle. Rotation limit specifies how much a connected body can rotate around the joint axis.

Return value

Low rotation limit angle in degrees.

voidsetAngularLimitTo(float to)

Sets a high rotation limit angle. Rotation limit specifies how much a connected body can rotate around the joint axis.

Arguments

• float to - Angle in degrees. The provided value will be saturated in the range [-180; 180].

floatgetAngularLimitTo()

Returns the high rotation limit angle. Rotation limit specifies how much a connected body can rotate around the joint axis.

Return value

High rotation limit angle in degrees.

voidsetAngularSpring(float spring)

Sets a rigidity coefficient of the angular spring.

Arguments

• float spring - Rigidity coefficient. If a negative value is provided, 0 will be used instead. 0 detaches the spring.

floatgetAngularSpring()

Returns the rigidity coefficient of the angular spring. 0 means that the spring is not attached.

Return value

Rigidity coefficient.

voidsetAngularTorque(float torque)

Sets a maximum torque of the angular motor.

Arguments

• float torque - Maximum torque. If a negative value is provided, 0 will be used instead. 0 detaches the motor.

floatgetAngularTorque()

Returns the maximum torque of the attached angular motor. 0 means that the motor is not attached.

Maximum torque.

voidsetAngularVelocity(float velocity)

Sets a target velocity of the attached angular motor.

Arguments

• float velocity - Velocity in radians per second.

floatgetAngularVelocity()

Returns the target velocity of the attached angular motor.

Return value

Target velocity in radians per second.

voidsetAxis0(const Math::vec3 & axis0)

Sets an axis of the first connected body.

Arguments

• const Math::vec3 & axis0 - Axis of the first body. The provided vector will be normalized.

Math::vec3getAxis0()

Returns the axis of the first connected body.

Return value

Axis of the first body.

voidsetAxis1(const Math::vec3 & axis1)

Sets an axis of the second connected body.

Arguments

• const Math::vec3 & axis1 - Axis of the second body. The provided vector will be normalized.

Math::vec3getAxis1()

Returns the axis of the second connected body.

Return value

Axis of the second body.

floatgetCurrentAngularAngle()

Returns the current angle between the bodies.

Return value

Current angle in degrees.

floatgetCurrentAngularVelocity()

Returns the current velocity of the motor, i.e. the difference between angular velocities of two bodies connected with a hinge relative the hinge axis.
Notice
This function returns the valid velocity only if both bodies are of BodyRigid type. Otherwise, 0 is returned.

Return value

Current motor velocity in radians per second.

voidsetWorldAxis(const Math::vec3 & axis)

Sets a joint axis. This method updates axes of the connected bodies.

Arguments

• const Math::vec3 & axis - Joint axis.

Math::vec3getWorldAxis()

Returns the joint axis. The joint axis is calculated based on the axes of the connected bodies.

Return value

Joint axis.
Last update: 10.08.2018