/*
* Copyright (c) 2009-2012 jMonkeyEngine
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* * Redistributions in binary form must reproduce the above copyright
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package com.jme3.bullet.joints;
import com.bulletphysics.dynamics.constraintsolver.HingeConstraint;
import com.jme3.bullet.objects.PhysicsRigidBody;
import com.jme3.bullet.util.Converter;
import com.jme3.export.InputCapsule;
import com.jme3.export.JmeExporter;
import com.jme3.export.JmeImporter;
import com.jme3.export.OutputCapsule;
import com.jme3.math.Vector3f;
import java.io.IOException;
/**
* <i>From bullet manual:</i><br>
* Hinge constraint, or revolute joint restricts two additional angular degrees of freedom,
* so the body can only rotate around one axis, the hinge axis.
* This can be useful to represent doors or wheels rotating around one axis.
* The user can specify limits and motor for the hinge.
* @author normenhansen
*/
public class HingeJoint extends PhysicsJoint {
protected Vector3f axisA;
protected Vector3f axisB;
protected boolean angularOnly = false;
protected float biasFactor = 0.3f;
protected float relaxationFactor = 1.0f;
protected float limitSoftness = 0.9f;
public HingeJoint() {
}
/**
* Creates a new HingeJoint
* @param pivotA local translation of the joint connection point in node A
* @param pivotB local translation of the joint connection point in node B
*/
public HingeJoint(PhysicsRigidBody nodeA, PhysicsRigidBody nodeB, Vector3f pivotA, Vector3f pivotB, Vector3f axisA, Vector3f axisB) {
super(nodeA, nodeB, pivotA, pivotB);
this.axisA = axisA;
this.axisB = axisB;
createJoint();
}
/**
* Enables the motor.
* @param enable if true, motor is enabled.
* @param targetVelocity the target velocity of the rotation.
* @param maxMotorImpulse the max force applied to the hinge to rotate it.
*/
public void enableMotor(boolean enable, float targetVelocity, float maxMotorImpulse) {
((HingeConstraint) constraint).enableAngularMotor(enable, targetVelocity, maxMotorImpulse);
}
/**
* Sets the limits of this joint.
* @param low the low limit in radians.
* @param high the high limit in radians.
*/
public void setLimit(float low, float high) {
((HingeConstraint) constraint).setLimit(low, high);
}
/**
* Sets the limits of this joint.
* If you're above the softness, velocities that would shoot through the actual limit are slowed down. The bias be in the range of 0.2 - 0.5.
* @param low the low limit in radians.
* @param high the high limit in radians.
* @param _softness the factor at which the velocity error correction starts operating,i.e a softness of 0.9 means that the vel. corr starts at 90% of the limit range.
* @param _biasFactor the magnitude of the position correction. It tells you how strictly the position error (drift ) is corrected.
* @param _relaxationFactor the rate at which velocity errors are corrected. This can be seen as the strength of the limits. A low value will make the the limits more spongy.
*/
public void setLimit(float low, float high, float _softness, float _biasFactor, float _relaxationFactor) {
biasFactor = _biasFactor;
relaxationFactor = _relaxationFactor;
limitSoftness = _softness;
((HingeConstraint) constraint).setLimit(low, high, _softness, _biasFactor, _relaxationFactor);
}
public float getUpperLimit(){
return ((HingeConstraint) constraint).getUpperLimit();
}
public float getLowerLimit(){
return ((HingeConstraint) constraint).getLowerLimit();
}
public void setAngularOnly(boolean angularOnly) {
this.angularOnly = angularOnly;
((HingeConstraint) constraint).setAngularOnly(angularOnly);
}
public float getHingeAngle() {
return ((HingeConstraint) constraint).getHingeAngle();
}
public void write(JmeExporter ex) throws IOException {
super.write(ex);
OutputCapsule capsule = ex.getCapsule(this);
capsule.write(axisA, "axisA", new Vector3f());
capsule.write(axisB, "axisB", new Vector3f());
capsule.write(angularOnly, "angularOnly", false);
capsule.write(((HingeConstraint) constraint).getLowerLimit(), "lowerLimit", 1e30f);
capsule.write(((HingeConstraint) constraint).getUpperLimit(), "upperLimit", -1e30f);
capsule.write(biasFactor, "biasFactor", 0.3f);
capsule.write(relaxationFactor, "relaxationFactor", 1f);
capsule.write(limitSoftness, "limitSoftness", 0.9f);
capsule.write(((HingeConstraint) constraint).getEnableAngularMotor(), "enableAngularMotor", false);
capsule.write(((HingeConstraint) constraint).getMotorTargetVelosity(), "targetVelocity", 0.0f);
capsule.write(((HingeConstraint) constraint).getMaxMotorImpulse(), "maxMotorImpulse", 0.0f);
}
public void read(JmeImporter im) throws IOException {
super.read(im);
InputCapsule capsule = im.getCapsule(this);
this.axisA = (Vector3f) capsule.readSavable("axisA", new Vector3f());
this.axisB = (Vector3f) capsule.readSavable("axisB", new Vector3f());
this.angularOnly = capsule.readBoolean("angularOnly", false);
float lowerLimit = capsule.readFloat("lowerLimit", 1e30f);
float upperLimit = capsule.readFloat("upperLimit", -1e30f);
this.biasFactor = capsule.readFloat("biasFactor", 0.3f);
this.relaxationFactor = capsule.readFloat("relaxationFactor", 1f);
this.limitSoftness = capsule.readFloat("limitSoftness", 0.9f);
boolean enableAngularMotor=capsule.readBoolean("enableAngularMotor", false);
float targetVelocity=capsule.readFloat("targetVelocity", 0.0f);
float maxMotorImpulse=capsule.readFloat("maxMotorImpulse", 0.0f);
createJoint();
enableMotor(enableAngularMotor, targetVelocity, maxMotorImpulse);
((HingeConstraint) constraint).setLimit(lowerLimit, upperLimit, limitSoftness, biasFactor, relaxationFactor);
}
protected void createJoint() {
constraint = new HingeConstraint(nodeA.getObjectId(), nodeB.getObjectId(),
Converter.convert(pivotA), Converter.convert(pivotB),
Converter.convert(axisA), Converter.convert(axisB));
}
}