fisica

Class FContactResult

java.lang.Object

fisica.FContactResult

public class FContactResult
extends Object

Represents the result of the contact between two bodies. Objects of this type are not created by the users. Contact results are passed to the user when they implement the contactResult(FContactResult){ } method in the applet:

 
 FWorld world;

 void setup() {
   Fisica.init(this);

   world = new FWorld();
   world.setEdges();

   // Create and add bodies to the world here
   // ...
 }

 void draw() {
   world.step();
   world.draw();
 }

 void contactResult(FContactResult result) {
   // Draw an ellipse where the contact took place and as big as the normal impulse of the contact
   ellipse(result.getX(), result.getY(), result.getNormalImpulse(), result.getNormalImpulse());

   // Trigger your sound here
   // ...
 }

 

To know if the contact is the beggining, the continuation or the end of a contact it is better to use the other methods contactStarted(FContact){ }, contactPersisted(FContact){ } and contactEnded(FContact){ }.

See Also:

FContact

Field Summary

Fields

Modifier and Type	Field and Description
protected FBody	m_body1
protected FBody	m_body2
protected fisica.FContactID	m_id
protected org.jbox2d.common.Vec2	m_normal
protected float	m_normalImpulse
protected org.jbox2d.common.Vec2	m_position
protected float	m_tangentImpulse

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FContactResult(org.jbox2d.dynamics.contacts.ContactResult contactResult)

Method Summary

Modifier and Type	Method and Description
FBody	getBody1() Returns the first body involved in the contact.
FBody	getBody2() Returns the second body involved in the contact.
fisica.FContactID	getId() Get the identifier of the contact.
float	getNormalImpulse() Returns the normal component of the impulse of the contact.
float	getNormalX() Returns the horizontal component of the contact normal.
float	getNormalY() Returns the vertical component of the contact normal.
float	getTangentImpulse() Returns the tangential component of the impulse of the contact.
float	getX() Returns the horizontal position of the contact point.
float	getY() Returns the vertical position of the contact point.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

m_position

protected org.jbox2d.common.Vec2 m_position

m_normal

protected org.jbox2d.common.Vec2 m_normal

m_body1

protected FBody m_body1

m_body2

protected FBody m_body2

m_normalImpulse

protected float m_normalImpulse

m_tangentImpulse

protected float m_tangentImpulse

m_id

protected fisica.FContactID m_id

Constructor Detail

FContactResult

protected FContactResult(org.jbox2d.dynamics.contacts.ContactResult contactResult)

Method Detail

getBody1

public FBody getBody1()

Returns the first body involved in the contact.

Returns:

first of the bodies involved in the contact

getBody2

public FBody getBody2()

Returns the second body involved in the contact.

Returns:

second of the bodies involved in the contact

getX

public float getX()

Returns the horizontal position of the contact point.

Returns:

the horizontal position of the contact point in pixels

See Also:

getY()

getY

public float getY()

Returns the vertical position of the contact point.

Returns:

the vertical position of the contact point in pixels

See Also:

getX()

getNormalX

public float getNormalX()

Returns the horizontal component of the contact normal.

Returns:

the horizontal component of the contact normal

See Also:

getNormalY()

getNormalY

public float getNormalY()

Returns the vertical component of the contact normal.

Returns:

the vertical component of the contact normal

See Also:

getNormalX()

getNormalImpulse

public float getNormalImpulse()

Returns the normal component of the impulse of the contact. This gives an idea of the strength of the collision that took place. This represents the impulse necessary to avoid penetration of the bodies involved in the collision. The impluse is simply the force multiplied by the timestep. The result is returned in impulse units (kg * pixels / s).

Returns:

the normal component of the contact's impulse

See Also:

getTangentImpulse()

getTangentImpulse

public float getTangentImpulse()

Returns the tangential component of the impulse of the contact. This gives an idea of the strength of the friction between the bodies that took place. The impluse is simply the force multiplied by the timestep. The result is returned in impulse units (kg * pixels / s).

Returns:

the tangent component of the contact's impulse

See Also:

getNormalImpulse()

getId

public fisica.FContactID getId()

Get the identifier of the contact. This value is useful in order to uniquely identify a contact. A new contact ID is created whenever to bodies enter into contact at a given point. If the bodies slide against each other the contact ID is maintained even if the point of contact is modified due to the slide. As soon as the two bodies separate the contact is considered ended.

Returns:

a unique identifier representing the contact