Unigine::Joint Class
Header: | #include <UniginePhysics.h> |
This class is used to simulate various types of joints and define common parameters shared by all joints.
See Also#
- A C++ API sample located in the <UnigineSDK>/source/samples/Api/Physics/JointCallbacks folder
- A C# API sample located in the <UnigineSDK>/source/csharp/samples/Api/Physics/JointCallbacks folder
- A UnigineScript API sample <UnigineSDK>/data/samples/physics/callbacks_03
Joint Class
Enums
TYPE#
Type of the joint defining its properties.Name | Description |
---|---|
JOINT_FIXED = 0 | Fixed joint. |
JOINT_BALL = 1 | Ball joint. |
JOINT_HINGE = 2 | Hinge joint. |
JOINT_PRISMATIC = 3 | Prismatic joint. |
JOINT_CYLINDRICAL = 4 | Cylindrical joint. |
JOINT_SUSPENSION = 5 | Suspension joint. |
JOINT_WHEEL = 6 | Wheel joint. |
JOINT_PARTICLES = 7 | Particles joint. |
JOINT_PATH = 8 | Path joint. |
NUM_JOINTS = 9 | Number of joints. |
Members
void setWorldAnchor ( const Math::Vec3& anchor ) #
Sets a new anchor point in the world coordinates.
Arguments
- const Math::Vec3& anchor - The coordinates of the anchor point in the world space.
Math::Vec3 getWorldAnchor() const#
Returns the current anchor point in the world coordinates.
Return value
Current coordinates of the anchor point in the world space.void setAnchor1 ( const Math::Vec3& anchor1 ) #
Sets a new coordinates of the anchor point in a system of coordinates of the second connected body.
Arguments
- const Math::Vec3& anchor1 - The coordinates of the anchor point in the body coordinate space.
Math::Vec3 getAnchor1() const#
Returns the current coordinates of the anchor point in a system of coordinates of the second connected body.
Return value
Current coordinates of the anchor point in the body coordinate space.void setAnchor0 ( const Math::Vec3& anchor0 ) #
Sets a new coordinates of the anchor point in a system of coordinates of the first connected body.
Arguments
- const Math::Vec3& anchor0 - The coordinates of the anchor point in the body coordinate space.
Math::Vec3 getAnchor0() const#
Returns the current coordinates of the anchor point in a system of coordinates of the first connected body.
Return value
Current coordinates of the anchor point in the body coordinate space.void setAngularSoftness ( float softness ) #
Sets a new angular softness (elasticity) of the joint. when the joint is twisted, angular softness defines whether angular velocities of the bodies are averaged out. for example:
- 0 means that the joint is rigid. Angular velocities of the first and the second body are independent.
- 1 means that the joint is elastic (jelly-like). If the first body changes its velocity, velocity of the second body is equalized with it.
Arguments
- float softness - The angular softness. The provided value will be clamped in the range [0;1].
float getAngularSoftness() const#
Returns the current angular softness (elasticity) of the joint. when the joint is twisted, angular softness defines whether angular velocities of the bodies are averaged out. for example:
- 0 means that the joint is rigid. Angular velocities of the first and the second body are independent.
- 1 means that the joint is elastic (jelly-like). If the first body changes its velocity, velocity of the second body is equalized with it.
Return value
Current angular softness. The provided value will be clamped in the range [0;1].void setLinearSoftness ( float softness ) #
Sets a new linear softness (elasticity) of the joint. when the joint is stretched, linear softness defines whether linear velocities of the bodies are averaged out. for example:
- 0 means that the joint is rigid. Velocities of the first and the second body are independent.
- 1 means that the joint is elastic (jelly-like). If the first body changes its velocity, velocity of the second body is equalized with it.
Arguments
- float softness - The linear softness. The provided value will be clamped in the range [0;1].
float getLinearSoftness() const#
Returns the current linear softness (elasticity) of the joint. when the joint is stretched, linear softness defines whether linear velocities of the bodies are averaged out. for example:
- 0 means that the joint is rigid. Velocities of the first and the second body are independent.
- 1 means that the joint is elastic (jelly-like). If the first body changes its velocity, velocity of the second body is equalized with it.
Return value
Current linear softness. The provided value will be clamped in the range [0;1].void setAngularRestitution ( float restitution ) #
Sets a new angular restitution (stiffness) of the joint. angular restitution defines how fast the joint compensates for change of the angle between two bodies. when bodies are turned relative each other, restitution controls the magnitude of force which is applied to both bodies so that their anchor points to become aligned again. for example:
- 1 means that the joint is to return bodies in place throughout 1 physics tick.
- 0.2 means that the joint is to return bodies in place throughout 5 physics ticks.
Arguments
- float restitution - The angular restitution. The provided value will be clamped in the range [0;1].
float getAngularRestitution() const#
Returns the current angular restitution (stiffness) of the joint. angular restitution defines how fast the joint compensates for change of the angle between two bodies. when bodies are turned relative each other, restitution controls the magnitude of force which is applied to both bodies so that their anchor points to become aligned again. for example:
- 1 means that the joint is to return bodies in place throughout 1 physics tick.
- 0.2 means that the joint is to return bodies in place throughout 5 physics ticks.
Return value
Current angular restitution. The provided value will be clamped in the range [0;1].void setLinearRestitution ( float restitution ) #
Sets a new linear restitution (stiffness) of the joint. linear restitution defines how fast the joint compensates for linear coordinate change between two bodies. when bodies are dragged apart, restitution controls the magnitude of force which is applied to both bodies so that their anchor points to become aligned again. for example:
- 1 means that the joint is to return bodies in place throughout 1 physics tick.
- 0.2 means that the joint is to return bodies in place throughout 5 physics ticks.
Arguments
- float restitution - The linear restitution. The provided value will be clamped in the range [0;1].
float getLinearRestitution() const#
Returns the current linear restitution (stiffness) of the joint. linear restitution defines how fast the joint compensates for linear coordinate change between two bodies. when bodies are dragged apart, restitution controls the magnitude of force which is applied to both bodies so that their anchor points to become aligned again. for example:
- 1 means that the joint is to return bodies in place throughout 1 physics tick.
- 0.2 means that the joint is to return bodies in place throughout 5 physics ticks.
Return value
Current linear restitution. The provided value will be clamped in the range [0;1].void setMaxTorque ( float torque ) #
Sets a new maximum amount of torque that can be exerted on the joint. if this limit is exceeded, the joint breaks.
Arguments
- float torque - The maximum amount of torque.
float getMaxTorque() const#
Returns the current maximum amount of torque that can be exerted on the joint. if this limit is exceeded, the joint breaks.
Return value
Current maximum amount of torque.void setMaxForce ( float force ) #
Sets a new maximum amount of force that can be exerted on the joint. if this limit is exceeded, the joint breaks.
Arguments
- float force - The maximum amount of force.
float getMaxForce() const#
Returns the current maximum amount of force that can be exerted on the joint. if this limit is exceeded, the joint breaks.
Return value
Current maximum amount of force.void setNumIterations ( int iterations ) #
Sets a new number of iterations used to solve joints. If a non-positive value is set as a value, 1 will be used instead.
Arguments
- int iterations - The number of iterations.
int getNumIterations() const#
Returns the current number of iterations used to solve joints. If a non-positive value is set as a value, 1 will be used instead.
Return value
Current number of iterations.void setName ( const char * name ) #
Sets a new name of the joint.
Arguments
- const char * name - The name of the joint.
const char * getName() const#
Returns the current name of the joint.
Return value
Current name of the joint.void setFrozen ( bool frozen ) #
Sets a new value indicating if the joint is frozen.
Arguments
- bool frozen - Set true to enable the joint frozen state; false - to disable it.
bool isFrozen() const#
Returns the current value indicating if the joint is frozen.
Return value
true if the joint frozen state is enabled; otherwise false.void setBroken ( bool broken ) #
Sets a new value indicating if the joint is broken or intact.
Arguments
- bool broken - Set true to enable the joint broken state; false - to disable it.
bool isBroken() const#
Returns the current value indicating if the joint is broken or intact.
Return value
true if the joint broken state is enabled; otherwise false.void setCollision ( int collision ) #
Sets a new value indicating if collisions between the connected bodies are enabled.
Arguments
- int collision - The value indicating if collisions between the connected bodies are enabled: positive number for enabled collisions between the bodies, 0 for disabled collisions.
int getCollision() const#
Returns the current value indicating if collisions between the connected bodies are enabled.
Return value
Current value indicating if collisions between the connected bodies are enabled: positive number for enabled collisions between the bodies, 0 for disabled collisions.bool isEnabledSelf() const#
Returns the current value indicating is the joint is enabled.
Return value
true if the joint is enabled; otherwise false.void setEnabled ( bool enabled ) #
Sets a new value indicating if the joint calculations are enabled.
Arguments
- bool enabled - Set true to enable the joint calculations; false - to disable it.
bool isEnabled() const#
Returns the current value indicating if the joint calculations are enabled.
Return value
true if the joint calculations is enabled; otherwise false.void setBody1 ( const Ptr<Body>& body1 ) #
Sets a new second body connected using the joint.
Arguments
Ptr<Body> getBody1() const#
Returns the current second body connected using the joint.
Return value
Current second body connected with the joint.void setBody0 ( const Ptr<Body>& body0 ) #
Sets a new first body connected using the joint.
Arguments
Ptr<Body> getBody0() const#
Returns the current first body connected using the joint.
Return value
Current first body connected with the joint.const char * getTypeName() const#
Returns the current name of the joint type.
Return value
Current name of the joint type.Joint::TYPE getType() const#
Returns the current type of the joint.
Return value
Current type of the joint, one of the JOINT_* pre-defined variables.void setNode1 ( const Ptr<Node>& node1 ) #
Sets a new node possessing the second body connected to the joint.
Arguments
- const Ptr<Node>& node1 - The node possessing the second body connected to the joint is assigned. The node must be an object and must have a body assigned.
Ptr<Node> getNode1() const#
Returns the current node possessing the second body connected to the joint.
Return value
Current node possessing the second body connected to the joint is assigned. The node must be an object and must have a body assigned.void setNode0 ( const Ptr<Node>& node0 ) #
Sets a new node possessing the first body connected to the joint.
Arguments
- const Ptr<Node>& node0 - The node possessing the first body connected to the joint is assigned. The node must be an object and must have a body assigned.
Ptr<Node> getNode0() const#
Returns the current node possessing the first body connected to the joint.
Return value
Current node possessing the first body connected to the joint is assigned. The node must be an object and must have a body assigned.Event<const Ptr<Joint> &> getEventBroken() const#
Event triggered when the joint breaks. The event handler must receive a Joint as an argument. You can subscribe to events via
connect()
and unsubscribe via
disconnect(). You can also use
EventConnection
and
EventConnections
classes for convenience (see examples below).
The event handler signature is as follows: myhandler(For more details see the Event Handling article.
Usage Example
// implement the Broken event handler
void broken_event_handler(const Ptr<Joint> & joint)
{
Log::message("\Handling Broken event\n");
}
//////////////////////////////////////////////////////////////////////////////
// 1. Multiple subscriptions can be linked to an instance of the EventConnections
// class that you can use later to remove all these subscriptions at once
//////////////////////////////////////////////////////////////////////////////
// create an instance of the EventConnections class
EventConnections broken_event_connections;
// link to this instance when subscribing to an event (subscription to various events can be linked)
publisher->getEventBroken().connect(broken_event_connections, broken_event_handler);
// other subscriptions are also linked to this EventConnections instance
// (e.g. you can subscribe using lambdas)
publisher->getEventBroken().connect(broken_event_connections, [](const Ptr<Joint> & joint) {
Log::message("\Handling Broken event (lambda).\n");
}
);
// ...
// later all of these linked subscriptions can be removed with a single line
broken_event_connections.disconnectAll();
//////////////////////////////////////////////////////////////////////////////
// 2. You can subscribe and unsubscribe via an instance of the EventConnection
// class. And toggle this particular connection off and on, when necessary.
//////////////////////////////////////////////////////////////////////////////
// create an instance of the EventConnection class
EventConnection broken_event_connection;
// subscribe to the Broken event with a handler function keeping the connection
publisher->getEventBroken().connect(broken_event_connection, broken_event_handler);
// ...
// you can temporarily disable a particular event connection to perform certain actions
broken_event_connection.setEnabled(false);
// ... actions to be performed
// and enable it back when necessary
broken_event_connection.setEnabled(true);
// ...
// remove subscription to the Broken event via the connection
broken_event_connection.disconnect();
//////////////////////////////////////////////////////////////////////////////
// 3. You can add EventConnection/EventConnections instance as a member of the
// class that handles the event. In this case all linked subscriptions will be
// automatically removed when class destructor is called
//////////////////////////////////////////////////////////////////////////////
// Class handling the event
class SomeClass
{
public:
// instance of the EventConnections class as a class member
EventConnections e_connections;
// A Broken event handler implemented as a class member
void event_handler(const Ptr<Joint> & joint)
{
Log::message("\Handling Broken event\n");
// ...
}
};
SomeClass *sc = new SomeClass();
// ...
// specify a class instance in case a handler method belongs to some class
publisher->getEventBroken().connect(sc->e_connections, sc, &SomeClass::event_handler);
// ...
// handler class instance is deleted with all its subscriptions removed automatically
delete sc;
//////////////////////////////////////////////////////////////////////////////
// 4. You can subscribe and unsubscribe via the handler function directly
//////////////////////////////////////////////////////////////////////////////
// subscribe to the Broken event with a handler function
publisher->getEventBroken().connect(broken_event_handler);
// remove subscription to the Broken event later by the handler function
publisher->getEventBroken().disconnect(broken_event_handler);
//////////////////////////////////////////////////////////////////////////////
// 5. Subscribe to an event saving an ID and unsubscribe later by this ID
//////////////////////////////////////////////////////////////////////////////
// define a connection ID to be used to unsubscribe later
EventConnectionId broken_handler_id;
// subscribe to the Broken event with a lambda handler function and keeping connection ID
broken_handler_id = publisher->getEventBroken().connect([](const Ptr<Joint> & joint) {
Log::message("\Handling Broken event (lambda).\n");
}
);
// remove the subscription later using the ID
publisher->getEventBroken().disconnect(broken_handler_id);
//////////////////////////////////////////////////////////////////////////////
// 6. Ignoring all Broken events when necessary
//////////////////////////////////////////////////////////////////////////////
// you can temporarily disable the event to perform certain actions without triggering it
publisher->getEventBroken().setEnabled(false);
// ... actions to be performed
// and enable it back when necessary
publisher->getEventBroken().setEnabled(true);
Return value
Event reference.Ptr<Joint> createJoint ( int type ) #
Creates a new joint of the specified type.Arguments
- int type - Joint type. One of the JOINT_* values.
Return value
New created joint smart pointer.Ptr<Joint> createJoint ( const char * type_name ) #
Creates a new joint of the specified type.Arguments
- const char * type_name - Joint type name.
Return value
New created joint smart pointer.Ptr<BodyRigid> getBodyRigid0 ( ) #
Returns the first connected body as a rigid body.Return value
The first rigid body connected using the joint or NULL (0), if the body is not rigid.Ptr<BodyRigid> getBodyRigid1 ( ) #
Returns the second connected body as a rigid body.Return value
The second rigid body connected using the joint or NULL (0), if the body is not rigid.int setID ( int id ) #
Sets the unique ID for the joint.Arguments
- int id - Unique ID.
Return value
1 if the ID is set successfully; otherwise, 0.int getID ( ) const#
Returns the unique ID of the joint.Return value
Unique ID.const char * getTypeName ( int type ) #
Returns the name of a joint type with a given ID.Arguments
- int type - Joint type ID. One of the JOINT_* values.
Return value
Joint type name.Ptr<Joint> clone ( ) const#
Clones the joint.Return value
Copy of the joint.void renderVisualizer ( const Math::vec4 & color ) #
Renders the joint.You should enable the engine visualizer by the show_visualizer 1 console command.
Arguments
- const Math::vec4 & color - Color, in which the joint will be rendered.
int saveState ( const Ptr<Stream> & stream ) const#
Saves the state of a given node into a binary stream.- If a node is a parent for other nodes, states of these child nodes need to be saved manually.
- To save the state from a buffer, file or a message from a socket, make sure the stream is opened. For buffers and files, you also need to set the proper position for reading.
Example using saveState() and restoreState() methods:
// set the joint state
joint->setAngularRestitution(0.8f);
// save state
BlobPtr blob_state = Blob::create();
joint->saveState(blob_state);
// change the state
joint->setAngularRestitution(0.4f);
// restore state
blob_state->seekSet(0); // returning the carriage to the start of the blob
joint->restoreState(blob_state);
Arguments
Return value
true if the node state is saved successfully; otherwise, false.int restoreState ( const Ptr<Stream> & stream ) #
Restores the state of a given node from a binary stream.- If a node is a parent for other nodes, states of these child nodes need to be restored manually.
- To save the state into a buffer, file or a message from a socket, make sure the stream is opened. If necessary, you can set a position for writing for buffers and files.
Example using saveState() and restoreState() methods:
// set the joint state
joint->setAngularRestitution(0.8f);
// save state
BlobPtr blob_state = Blob::create();
joint->saveState(blob_state);
// change the state
joint->setAngularRestitution(0.4f);
// restore state
blob_state->seekSet(0); // returning the carriage to the start of the blob
joint->restoreState(blob_state);
Arguments
Return value
true if the node state is restored successfully; otherwise, false.void swap ( const Ptr<Joint> & joint ) #
Swaps the joints saving the pointers.Arguments
- const Ptr<Joint> & joint - A joint to swap.
Last update:
2024-04-19
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