Java 类com.badlogic.gdx.physics.box2d.joints.DistanceJoint 实例源码

public DistanceJoint createDistanceJoint(Body bodyA, Body bodyB,
    Vector2 localA, Vector2 localB, int length) {
DistanceJointDef dJoint = new DistanceJointDef();
dJoint.bodyA = bodyA;
dJoint.bodyB = bodyB;
dJoint.localAnchorA.set(localA.x * WORLD_TO_BOX, localA.y
    * WORLD_TO_BOX);
dJoint.localAnchorB.set(localB.x * WORLD_TO_BOX, localB.y
    * WORLD_TO_BOX);
dJoint.length = length * WORLD_TO_BOX;
return (DistanceJoint) world.createJoint(dJoint);
   }

public DistanceJoint createDistanceJoint(Body bodyA, Body bodyB,
        Vector2 localA, Vector2 localB, int length) {
    DistanceJointDef dJoint = new DistanceJointDef();
    dJoint.bodyA = bodyA;
    dJoint.bodyB = bodyB;
    dJoint.localAnchorA.set(localA.x * WORLD_TO_BOX, localA.y
            * WORLD_TO_BOX);
    dJoint.localAnchorB.set(localB.x * WORLD_TO_BOX, localB.y
            * WORLD_TO_BOX);
    dJoint.length = length * WORLD_TO_BOX;
    return (DistanceJoint) world.createJoint(dJoint);
}

/**
 * When a hero collides with a "sticky" obstacle, this figures out what to do
 *
 * @param sticky  The sticky actor... it should always be an obstacle for now
 * @param other   The other actor... it should always be a hero for now
 * @param contact A description of the contact event
 */
private void handleSticky(final WorldActor sticky, final WorldActor other, Contact contact) {
    // don't create a joint if we've already got one
    if (other.mDJoint != null)
        return;
    // don't create a joint if we're supposed to wait
    if (System.currentTimeMillis() < other.mStickyDelay)
        return;
    // go sticky obstacles... only do something if we're hitting the
    // obstacle from the correct direction
    if ((sticky.mIsSticky[0] && other.getYPosition() >= sticky.getYPosition() + sticky.mSize.y)
            || (sticky.mIsSticky[1] && other.getXPosition() + other.mSize.x <= sticky.getXPosition())
            || (sticky.mIsSticky[3] && other.getXPosition() >= sticky.getXPosition() + sticky.mSize.x)
            || (sticky.mIsSticky[2] && other.getYPosition() + other.mSize.y <= sticky.getYPosition())) {
        // create distance and weld joints... somehow, the combination is needed to get this to
        // work. Note that this function runs during the box2d step, so we need to make the
        // joint in a callback that runs later
        final Vector2 v = contact.getWorldManifold().getPoints()[0];
        mOneTimeEvents.add(new LolAction() {
            @Override
            public void go() {
                other.mBody.setLinearVelocity(0, 0);
                DistanceJointDef d = new DistanceJointDef();
                d.initialize(sticky.mBody, other.mBody, v, v);
                d.collideConnected = true;
                other.mDJoint = (DistanceJoint) mWorld.createJoint(d);
                WeldJointDef w = new WeldJointDef();
                w.initialize(sticky.mBody, other.mBody, v);
                w.collideConnected = true;
                other.mWJoint = (WeldJoint) mWorld.createJoint(w);
            }
        });
    }
}

public DistanceJoint createDistanceJoint(Body bodyA, Body bodyB, int length) {
return createDistanceJoint(bodyA, bodyB, Vector2.Zero, Vector2.Zero,
    length);
   }

public DistanceJoint createDistanceJoint(Body bodyA, Body bodyB, int length) {
    return createDistanceJoint(bodyA, bodyB, Vector2.Zero, Vector2.Zero,
            length);
}

@Override
public DistanceJoint getJoint(){return (DistanceJoint) joint;}

private long createProperJoint(JointDef paramJointDef)
{
  if (paramJointDef.type == JointDef.JointType.DistanceJoint)
  {
    DistanceJointDef localDistanceJointDef = (DistanceJointDef)paramJointDef;
    return jniCreateDistanceJoint(this.addr, localDistanceJointDef.bodyA.addr, localDistanceJointDef.bodyB.addr, localDistanceJointDef.collideConnected, localDistanceJointDef.localAnchorA.x, localDistanceJointDef.localAnchorA.y, localDistanceJointDef.localAnchorB.x, localDistanceJointDef.localAnchorB.y, localDistanceJointDef.length, localDistanceJointDef.frequencyHz, localDistanceJointDef.dampingRatio);
  }
  if (paramJointDef.type == JointDef.JointType.FrictionJoint)
  {
    FrictionJointDef localFrictionJointDef = (FrictionJointDef)paramJointDef;
    return jniCreateFrictionJoint(this.addr, localFrictionJointDef.bodyA.addr, localFrictionJointDef.bodyB.addr, localFrictionJointDef.collideConnected, localFrictionJointDef.localAnchorA.x, localFrictionJointDef.localAnchorA.y, localFrictionJointDef.localAnchorB.x, localFrictionJointDef.localAnchorB.y, localFrictionJointDef.maxForce, localFrictionJointDef.maxTorque);
  }
  if (paramJointDef.type == JointDef.JointType.GearJoint)
  {
    GearJointDef localGearJointDef = (GearJointDef)paramJointDef;
    return jniCreateGearJoint(this.addr, localGearJointDef.bodyA.addr, localGearJointDef.bodyB.addr, localGearJointDef.collideConnected, localGearJointDef.joint1.addr, localGearJointDef.joint2.addr, localGearJointDef.ratio);
  }
  if (paramJointDef.type == JointDef.JointType.MouseJoint)
  {
    MouseJointDef localMouseJointDef = (MouseJointDef)paramJointDef;
    return jniCreateMouseJoint(this.addr, localMouseJointDef.bodyA.addr, localMouseJointDef.bodyB.addr, localMouseJointDef.collideConnected, localMouseJointDef.target.x, localMouseJointDef.target.y, localMouseJointDef.maxForce, localMouseJointDef.frequencyHz, localMouseJointDef.dampingRatio);
  }
  if (paramJointDef.type == JointDef.JointType.PrismaticJoint)
  {
    PrismaticJointDef localPrismaticJointDef = (PrismaticJointDef)paramJointDef;
    return jniCreatePrismaticJoint(this.addr, localPrismaticJointDef.bodyA.addr, localPrismaticJointDef.bodyB.addr, localPrismaticJointDef.collideConnected, localPrismaticJointDef.localAnchorA.x, localPrismaticJointDef.localAnchorA.y, localPrismaticJointDef.localAnchorB.x, localPrismaticJointDef.localAnchorB.y, localPrismaticJointDef.localAxisA.x, localPrismaticJointDef.localAxisA.y, localPrismaticJointDef.referenceAngle, localPrismaticJointDef.enableLimit, localPrismaticJointDef.lowerTranslation, localPrismaticJointDef.upperTranslation, localPrismaticJointDef.enableMotor, localPrismaticJointDef.maxMotorForce, localPrismaticJointDef.motorSpeed);
  }
  if (paramJointDef.type == JointDef.JointType.PulleyJoint)
  {
    PulleyJointDef localPulleyJointDef = (PulleyJointDef)paramJointDef;
    return jniCreatePulleyJoint(this.addr, localPulleyJointDef.bodyA.addr, localPulleyJointDef.bodyB.addr, localPulleyJointDef.collideConnected, localPulleyJointDef.groundAnchorA.x, localPulleyJointDef.groundAnchorA.y, localPulleyJointDef.groundAnchorB.x, localPulleyJointDef.groundAnchorB.y, localPulleyJointDef.localAnchorA.x, localPulleyJointDef.localAnchorA.y, localPulleyJointDef.localAnchorB.x, localPulleyJointDef.localAnchorB.y, localPulleyJointDef.lengthA, localPulleyJointDef.lengthB, localPulleyJointDef.ratio);
  }
  if (paramJointDef.type == JointDef.JointType.RevoluteJoint)
  {
    RevoluteJointDef localRevoluteJointDef = (RevoluteJointDef)paramJointDef;
    return jniCreateRevoluteJoint(this.addr, localRevoluteJointDef.bodyA.addr, localRevoluteJointDef.bodyB.addr, localRevoluteJointDef.collideConnected, localRevoluteJointDef.localAnchorA.x, localRevoluteJointDef.localAnchorA.y, localRevoluteJointDef.localAnchorB.x, localRevoluteJointDef.localAnchorB.y, localRevoluteJointDef.referenceAngle, localRevoluteJointDef.enableLimit, localRevoluteJointDef.lowerAngle, localRevoluteJointDef.upperAngle, localRevoluteJointDef.enableMotor, localRevoluteJointDef.motorSpeed, localRevoluteJointDef.maxMotorTorque);
  }
  if (paramJointDef.type == JointDef.JointType.WeldJoint)
  {
    WeldJointDef localWeldJointDef = (WeldJointDef)paramJointDef;
    return jniCreateWeldJoint(this.addr, localWeldJointDef.bodyA.addr, localWeldJointDef.bodyB.addr, localWeldJointDef.collideConnected, localWeldJointDef.localAnchorA.x, localWeldJointDef.localAnchorA.y, localWeldJointDef.localAnchorB.x, localWeldJointDef.localAnchorB.y, localWeldJointDef.referenceAngle);
  }
  if (paramJointDef.type == JointDef.JointType.RopeJoint)
  {
    RopeJointDef localRopeJointDef = (RopeJointDef)paramJointDef;
    return jniCreateRopeJoint(this.addr, localRopeJointDef.bodyA.addr, localRopeJointDef.bodyB.addr, localRopeJointDef.collideConnected, localRopeJointDef.localAnchorA.x, localRopeJointDef.localAnchorA.y, localRopeJointDef.localAnchorB.x, localRopeJointDef.localAnchorB.y, localRopeJointDef.maxLength);
  }
  if (paramJointDef.type == JointDef.JointType.WheelJoint)
  {
    WheelJointDef localWheelJointDef = (WheelJointDef)paramJointDef;
    return jniCreateWheelJoint(this.addr, localWheelJointDef.bodyA.addr, localWheelJointDef.bodyB.addr, localWheelJointDef.collideConnected, localWheelJointDef.localAnchorA.x, localWheelJointDef.localAnchorA.y, localWheelJointDef.localAnchorB.x, localWheelJointDef.localAnchorB.y, localWheelJointDef.localAxisA.x, localWheelJointDef.localAxisA.y, localWheelJointDef.enableMotor, localWheelJointDef.maxMotorTorque, localWheelJointDef.motorSpeed, localWheelJointDef.frequencyHz, localWheelJointDef.dampingRatio);
  }
  return 0L;
}

/**
 * Modify an existing distance joint by changing the distance between the actors
 *
 * @param newDist The new distance between the actors involved in the joint
 */
public void setDistance(float newDist) {
    DistanceJoint dj = (DistanceJoint) mDistJoint;
    dj.setLength(newDist);
}