Unigine.PhysicalTrigger Class

To force update of the physical trigger updateContacts() can be called. After that, you can access all updated data about the contacts in the same frame. However, handler functions will still be executed only when the next engine function is called: that is, before updatePhysics() (in the current frame), or before the update() (in the next frame) — whatever comes first.

Notice

If you have moved some nodes and want to execute event handlers based on changed positions in the same frame, you need to call updateSpatial() first.

Usage Example#

In this example a physical trigger and two boxes, each with a body and a shape, are created. When a box with matching physical mask enters the physical trigger the trigger_enter() function is called, when it leaves the trigger - the trigger_leave() function is called.

Source code (C#)

using System;
using System.Collections;
using System.Collections.Generic;
using Unigine;
using System.Linq;
using System.Text;

#region Math Variables
#if UNIGINE_DOUBLE
using Scalar = System.Double;
using Vec2 = Unigine.dvec2;
using Vec3 = Unigine.dvec3;
using Vec4 = Unigine.dvec4;
using Mat4 = Unigine.dmat4;
#else
using Scalar = System.Single;
using Vec2 = Unigine.vec2;
using Vec3 = Unigine.vec3;
using Vec4 = Unigine.vec4;
using Mat4 = Unigine.mat4;
using WorldBoundBox = Unigine.BoundBox;
using WorldBoundSphere = Unigine.BoundSphere;
using WorldBoundFrustum = Unigine.BoundFrustum;
#endif
#endregion

[Component(PropertyGuid = "AUTOGENERATED_GUID")] // <-- this line is generated automatically for a new component
public class name : Component
{
	PhysicalTrigger trigger;
	EventConnections trigger_event_connections = new EventConnections();
	ObjectMeshDynamic box1;
	ObjectMeshDynamic box2;
	
	// function to be executed when a physical object enters the trigger
	private void trigger_enter(Body body)
	{
		// trying to get an object from the body
		Unigine.Object obj = body.Object;
		if (!obj)
			return;
		
		// enabling material emission for all object's surfaces
		for (int i = 0; i < obj.NumSurfaces; i++)
			obj.SetMaterialState("emission", 1, i);

		// displaying the name of the object entering trigger area
		Log.Message("\n {0} has entered the trigger area!", body.Object.Name);
	}

	// function to be executed when a physical object leaves the trigger
	private void trigger_leave(Body body)
	{
		// trying to get an object from the body
		Unigine.Object obj = body.Object;
		if (!obj)
			return;
		
		// disabling material emission for all object's surfaces
		for (int i = 0; i < obj.NumSurfaces; i++)
			obj.SetMaterialState("emission", 0, i);

		// displaying the name of the object leaving trigger area
		Log.Message("\n {0} has left the trigger area!", body.Object.Name);
	}

	/// function, creating a named box having a specified size, color and transformation with a body and a shape
	ObjectMeshDynamic createBodyBox(String name, vec3 size, float mass, vec4 color, Mat4 transform, int physical_mask)
	{
		// creating geometry and setting up its parameters (name, material and transformation)
		ObjectMeshDynamic OMD = Primitives.CreateBox(size);
		OMD.WorldTransform = transform;
		OMD.SetMaterialParameterFloat4("albedo_color", color, 0);
		OMD.Name = name;

		// adding physics, i.e. a rigid body and a box shape with specified mass
		BodyRigid body = new BodyRigid(OMD);

		body.AddShape(new ShapeBox(size), MathLib.Translate(new vec3(0.0f)));
		body.PhysicalMask = physical_mask;
		body.Mass = mass;

		return OMD;
	}
	
	private void Init()
	{
			// enabling visualizer to render bounds of the physical trigger	
			Unigine.Console.Run("show_visualizer 1");

			// creating a physical trigger
			trigger = new PhysicalTrigger(Shape.TYPE.SHAPE_BOX,new vec3(2.0f, 2.0f, 1.0f));

			// setting trigger's position
			trigger.Position = new Vec3(0.0f, 0.0f, 1.0f);

			// setting trigger's physical mask equal to 1
			trigger.PhysicalMask = 1;

			// retrieving trigger size
			vec3 size = trigger.Size;
	
			// displaying trigger size and shape type
			Log.Message("\n Trigger parameters size({0}, {1} , {2}) type: {3}", size.x, size.y, size.z, trigger.ShapeType);
	
			// subscribing for the Enter event 
			trigger.EventEnter.Connect(trigger_event_connections, body => trigger_enter(body));

			// subscribing for the Leave event 
			trigger.EventLeave.Connect(trigger_event_connections, body => trigger_leave(body));

			// creating a box with a body and physical mask value equal to 2 to be ignored by the trigger
			box1 = createBodyBox("Box1", new vec3(0.2f), 5.0f, new vec4(1.0f, 0.0f, 0.0f, 1.0f), MathLib.Translate(new Vec3(0.0f, 0.0f, 2.22f)),2);

			// creating a box with a body and physical mask value equal to 1 to affect the trigger
			box2 = createBodyBox("Box2", new vec3(0.2f), 0.0f, new vec4(1.0f, 1.0f, 0.0f, 1.0f), MathLib.Translate(new Vec3(3.5f, 0.0f, 1.2f)),1);

			// displaying physical masks of both boxes and the trigger
			Log.Message("\n Box1 Physical mask: {0}", box1.Body.PhysicalMask);
			Log.Message("\n Box2 Physical mask: {0}", box2.Body.PhysicalMask);
			Log.Message("\n Trigger Physical mask: {0}", trigger.PhysicalMask);
	}
	
	private void Update()
	{
		// showing the bounds of the physical trigger
		trigger.RenderVisualizer();

		// changing the position of the second box
		box2.WorldPosition = box2.WorldPosition - new vec3(0.5f * Game.IFps, 0.0f, 0.0f);
			
	}

	private void UpdatePhysics()
	{
		
		// updating information on trigger contacts
		trigger.UpdateContacts();
		
	}
	
	private void Shutdown()
	{
		
		// unsubscribing from all events
		trigger_event_connections.DisconnectAll();
	}
}

Properties:

Name	Description
vec3 Size	The size of the physical trigger.
int ShapeType	The shape type of the physical trigger.
int NumContacts	The total number of contacts with bodies, shapes, and colliding surfaces in which a physical trigger participated.
int NumBodies	The total number of bodies intersecting with the physical trigger.
string LeaveCallbackName	The name of the callback function fired on leaving the physical trigger.
int ExclusionMask	The bit mask that prevents detecting collisions with shapes and bodies.
string EnterCallbackName	The name of the callback function fired on entering the physical trigger.
int CollisionMask	The collision bit mask for the trigger: the trigger will be activated if the entered body will have a matching physical mask and at the same time its shape will have a matching collision mask.
Event<Body> EventLeave	The Event triggered when a body enters the physical trigger.
Event<Body> EventEnter	The Event triggered when a body leaves the physical trigger.

Methods:

Name	Description View: Sort by:
PhysicalTrigger	Constructor.
GetBody	Returns the specified body that intersects the physical trigger.
GetContactDepth	Returns penetration depth by the given contact.
GetContactNormal	Returns a normal of the contact point, in world coordinates.
GetContactObject	Returns an object participating in the contact with a physical trigger .
GetContactPoint	Returns world coordinates of the contact point.
GetContactShape	Returns a shape that collided with a physical trigger.
GetContactSurface	Returns the surface of the current object, which is in contact .
type	Returns the type of the node.
UpdateContacts	Forces a physical trigger to be updated, i.e. to recalculate its intersections with physical objects and colliders.

PhysicalTrigger Class

Properties

vec3 Size#

The size of the physical trigger.

int ShapeType#

The shape type of the physical trigger.

int NumContacts#

The total number of contacts with bodies, shapes, and colliding surfaces in which a physical trigger participated.

int NumBodies#

The total number of bodies intersecting with the physical trigger.

string LeaveCallbackName#

The name of the callback function fired on leaving the physical trigger. This callback function is set via setLeaveCallbackName() .

int ExclusionMask#

The bit mask that prevents detecting collisions with shapes and bodies. This mask is independent of the collision mask. To avoid detecting collisions by a physical trigger for bodies and shapes with matching collision masks, at least one bit in exclusion masks should match.

string EnterCallbackName#

The name of the callback function fired on entering the physical trigger.

int CollisionMask#

The collision bit mask for the trigger:

the trigger will be activated if the entered body will have a matching physical mask and at the same time its shape will have a matching collision mask.

Event<Body> EventLeave#

The Event triggered when a body enters the physical trigger. The event handler must receive a Body as its first argument. In addition, it can also take 2 arguments of any type. You can subscribe to events via Connect() and unsubscribe via Disconnect(). You can also use EventConnection and EventConnections classes for convenience (see examples below).

Notice

For more details see the Event Handling article.

The event handler signature is as follows: myhandler(Body body)

Usage Example

Source code (C#)

// implement the Leave event handler
void leave_event_handler(Body body)
{
	Log.Message("\Handling Leave event\n");
}

//////////////////////////////////////////////////////////////////////////////
//  1. Multiple subscriptions can be linked to an EventConnections instance
//  class that you can use later to remove all these subscriptions at once
//////////////////////////////////////////////////////////////////////////////

// create an instance of the EventConnections class
EventConnections leave_event_connections = new EventConnections();


// link to this instance when subscribing to an event (subscription to various events can be linked)
publisher.EventLeave.Connect(leave_event_connections, leave_event_handler);

// other subscriptions are also linked to this EventConnections instance 
// (e.g. you can subscribe using lambdas)
publisher.EventLeave.Connect(leave_event_connections, (Body body) => { 
		Log.Message("Handling Leave event lambda\n");
		}
	);

// later all of these linked subscriptions can be removed with a single line
leave_event_connections.DisconnectAll();

//////////////////////////////////////////////////////////////////////////////
//  2. You can subscribe and unsubscribe via the handler function directly
//////////////////////////////////////////////////////////////////////////////

// subscribe to the Leave event with a handler function
publisher.EventLeave.Connect(leave_event_handler);


// remove subscription to the Leave event later by the handler function
publisher.EventLeave.Disconnect(leave_event_handler);


//////////////////////////////////////////////////////////////////////////////
//   3. Subscribe to an event and unsubscribe later via an EventConnection instance
//////////////////////////////////////////////////////////////////////////////

// define a connection to be used to unsubscribe later
EventConnection leave_event_connection;

// subscribe to the Leave event with a lambda handler function and keeping the connection
leave_event_connection = publisher.EventLeave.Connect((Body body) => { 
		Log.Message("Handling Leave event lambda\n");
	}
);

// ...

// you can temporarily disable a particular event connection 
leave_event_connection.Enabled = false;

// ... perform certain actions

// and enable it back when necessary
leave_event_connection.Enabled = true;

// ...

// remove the subscription later using the saved connection
leave_event_connection.Disconnect();

//////////////////////////////////////////////////////////////////////////////
//   4. Ignoring Leave events when necessary
//////////////////////////////////////////////////////////////////////////////

// you can temporarily disable the event to perform certain actions without triggering it
publisher.EventLeave.Enabled = false;

// ... actions to be performed

// and enable it back when necessary
publisher.EventLeave.Enabled = true;

Event<Body> EventEnter#

The Event triggered when a body leaves the physical trigger. The callback function must receive a Body as its first argument. In addition, it can also take 2 arguments of any type. You can subscribe to events via Connect() and unsubscribe via Disconnect(). You can also use EventConnection and EventConnections classes for convenience (see examples below).

Notice

For more details see the Event Handling article.

The event handler signature is as follows: myhandler(Body body)

Usage Example

Source code (C#)

// implement the Enter event handler
void enter_event_handler(Body body)
{
	Log.Message("\Handling Enter event\n");
}

//////////////////////////////////////////////////////////////////////////////
//  1. Multiple subscriptions can be linked to an EventConnections instance
//  class that you can use later to remove all these subscriptions at once
//////////////////////////////////////////////////////////////////////////////

// create an instance of the EventConnections class
EventConnections enter_event_connections = new EventConnections();


// link to this instance when subscribing to an event (subscription to various events can be linked)
publisher.EventEnter.Connect(enter_event_connections, enter_event_handler);

// other subscriptions are also linked to this EventConnections instance 
// (e.g. you can subscribe using lambdas)
publisher.EventEnter.Connect(enter_event_connections, (Body body) => { 
		Log.Message("Handling Enter event lambda\n");
		}
	);

// later all of these linked subscriptions can be removed with a single line
enter_event_connections.DisconnectAll();

//////////////////////////////////////////////////////////////////////////////
//  2. You can subscribe and unsubscribe via the handler function directly
//////////////////////////////////////////////////////////////////////////////

// subscribe to the Enter event with a handler function
publisher.EventEnter.Connect(enter_event_handler);


// remove subscription to the Enter event later by the handler function
publisher.EventEnter.Disconnect(enter_event_handler);


//////////////////////////////////////////////////////////////////////////////
//   3. Subscribe to an event and unsubscribe later via an EventConnection instance
//////////////////////////////////////////////////////////////////////////////

// define a connection to be used to unsubscribe later
EventConnection enter_event_connection;

// subscribe to the Enter event with a lambda handler function and keeping the connection
enter_event_connection = publisher.EventEnter.Connect((Body body) => { 
		Log.Message("Handling Enter event lambda\n");
	}
);

// ...

// you can temporarily disable a particular event connection 
enter_event_connection.Enabled = false;

// ... perform certain actions

// and enable it back when necessary
enter_event_connection.Enabled = true;

// ...

// remove the subscription later using the saved connection
enter_event_connection.Disconnect();

//////////////////////////////////////////////////////////////////////////////
//   4. Ignoring Enter events when necessary
//////////////////////////////////////////////////////////////////////////////

// you can temporarily disable the event to perform certain actions without triggering it
publisher.EventEnter.Enabled = false;

// ... actions to be performed

// and enable it back when necessary
publisher.EventEnter.Enabled = true;

Members

PhysicalTrigger ( Shape.TYPE type, vec3 size ) #

Constructor. Creates a physical trigger of the specified shape and size.

Arguments

Shape.TYPE type - Shape of the physical trigger:
- 0 = Sphere
- 1 = Capsule
- 2 = Cylinder
- 3 = Box
vec3 size - Size of the physical trigger:
- Radius, in case of a sphere
- Radius and height, in case of a capsule or a cylinder
- Dimensions, in case of the box

Body GetBody ( int num ) #

Returns the specified body that intersects the physical trigger.

Arguments

int num - Body number.

Return value

Intersected body.

float GetContactDepth ( int contact ) #

Returns penetration depth by the given contact.

Arguments

int contact - Contact number.

Return value

Penetration depth.

vec3 GetContactNormal ( int contact ) #

Returns a normal of the contact point, in world coordinates.

Arguments

int contact - Contact number.

Return value

Normal of the contact point.

Object GetContactObject ( int contact ) #

Returns an object participating in the contact with a physical trigger .

Arguments

int contact - Contact number.

Return value

Object in contact.

vec3 GetContactPoint ( int contact ) #

Returns world coordinates of the contact point.

Arguments

int contact - Contact number.

Return value

Contact point.

Shape GetContactShape ( int contact ) #

Returns a shape that collided with a physical trigger.

Arguments

int contact - Contact number.

Return value

Shape in contact.

int GetContactSurface ( int contact ) #

Returns the surface of the current object, which is in contact .

Arguments

int contact - Contact number.

Return value

Surface number.

static int type ( ) #

Returns the type of the node.

Return value

Physical trigger type identifier.

void UpdateContacts ( ) #

Forces a physical trigger to be updated, i.e. to recalculate its intersections with physical objects and colliders. After that, you can access all updated data; however, event handler functions themselves will be executed only when physics flush is over.

Last update: 2024-08-01

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Unigine.PhysicalTrigger Class

In This Article:

See Also#

Usage Example#

Properties:

Methods:

PhysicalTrigger Class

Properties

vec3 Size#

int ShapeType#

int NumContacts#

int NumBodies#

string LeaveCallbackName#

int ExclusionMask#

string EnterCallbackName#

int CollisionMask#

Event<Body> EventLeave#

Event<Body> EventEnter#

Members

PhysicalTrigger ( Shape.TYPE type, vec3 size ) #

Arguments

Body GetBody ( int num ) #

Arguments

Return value

float GetContactDepth ( int contact ) #

Arguments

Return value

vec3 GetContactNormal ( int contact ) #

Arguments

Return value

Object GetContactObject ( int contact ) #

Arguments

Return value

vec3 GetContactPoint ( int contact ) #

Arguments

Return value

Shape GetContactShape ( int contact ) #

Arguments

Return value

int GetContactSurface ( int contact ) #

Arguments

Return value

static int type ( ) #

Return value

void UpdateContacts ( ) #