/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.badlogic.gdx.physics.box2d.joints;
import com.badlogic.gdx.math.Vector2;
import com.badlogic.gdx.physics.box2d.Joint;
import com.badlogic.gdx.physics.box2d.World;
/** A revolute joint constrains two bodies to share a common point while they are free to rotate about the point. The relative
* rotation about the shared point is the joint angle. You can limit the relative rotation with a joint limit that specifies a
* lower and upper angle. You can use a motor to drive the relative rotation about the shared point. A maximum motor torque is
* provided so that infinite forces are not generated. */
public class RevoluteJoint extends Joint {
// @off
/*JNI
#include <Box2D/Box2D.h>
*/
/** Get the first ground anchor. */
private final float[] tmp = new float[2];
private final Vector2 localAnchorA = new Vector2();
private final Vector2 localAnchorB = new Vector2();
public RevoluteJoint (World world, long addr) {
super(world, addr);
}
/** Get the current joint angle in radians. */
public float getJointAngle () {
return jniGetJointAngle(addr);
}
private native float jniGetJointAngle (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetJointAngle();
*/
/** Get the current joint angle speed in radians per second. */
public float getJointSpeed () {
return jniGetJointSpeed(addr);
}
private native float jniGetJointSpeed (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetJointSpeed();
*/
/** Is the joint limit enabled? */
public boolean isLimitEnabled () {
return jniIsLimitEnabled(addr);
}
private native boolean jniIsLimitEnabled (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->IsLimitEnabled();
*/
/** Enable/disable the joint limit. */
public void enableLimit (boolean flag) {
jniEnableLimit(addr, flag);
}
private native void jniEnableLimit (long addr, boolean flag); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
joint->EnableLimit(flag);
*/
/** Get the lower joint limit in radians. */
public float getLowerLimit () {
return jniGetLowerLimit(addr);
}
private native float jniGetLowerLimit (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetLowerLimit();
*/
/** Get the upper joint limit in radians. */
public float getUpperLimit () {
return jniGetUpperLimit(addr);
}
private native float jniGetUpperLimit (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetUpperLimit();
*/
/** Set the joint limits in radians.
* @param upper */
public void setLimits (float lower, float upper) {
jniSetLimits(addr, lower, upper);
}
private native void jniSetLimits (long addr, float lower, float upper); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
joint->SetLimits(lower, upper );
*/
/** Is the joint motor enabled? */
public boolean isMotorEnabled () {
return jniIsMotorEnabled(addr);
}
private native boolean jniIsMotorEnabled (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->IsMotorEnabled();
*/
/** Enable/disable the joint motor. */
public void enableMotor (boolean flag) {
jniEnableMotor(addr, flag);
}
private native void jniEnableMotor (long addr, boolean flag); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
joint->EnableMotor(flag);
*/
/** Set the motor speed in radians per second. */
public void setMotorSpeed (float speed) {
jniSetMotorSpeed(addr, speed);
}
private native void jniSetMotorSpeed (long addr, float speed); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
joint->SetMotorSpeed(speed);
*/
/** Get the motor speed in radians per second. */
public float getMotorSpeed () {
return jniGetMotorSpeed(addr);
}
private native float jniGetMotorSpeed (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetMotorSpeed();
*/
/** Set the maximum motor torque, usually in N-m. */
public void setMaxMotorTorque (float torque) {
jniSetMaxMotorTorque(addr, torque);
}
private native void jniSetMaxMotorTorque (long addr, float torque); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
joint->SetMaxMotorTorque(torque);
*/
/** Get the current motor torque, usually in N-m. */
public float getMotorTorque (float invDt) {
return jniGetMotorTorque(addr, invDt);
}
private native float jniGetMotorTorque (long addr, float invDt); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetMotorTorque(invDt);
*/
public Vector2 getLocalAnchorA () {
jniGetLocalAnchorA(addr, tmp);
localAnchorA.set(tmp[0], tmp[1]);
return localAnchorA;
}
private native void jniGetLocalAnchorA (long addr, float[] anchor); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
anchor[0] = joint->GetLocalAnchorA().x;
anchor[1] = joint->GetLocalAnchorA().y;
*/
public Vector2 getLocalAnchorB () {
jniGetLocalAnchorB(addr, tmp);
localAnchorB.set(tmp[0], tmp[1]);
return localAnchorB;
}
private native void jniGetLocalAnchorB (long addr, float[] anchor); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
anchor[0] = joint->GetLocalAnchorB().x;
anchor[1] = joint->GetLocalAnchorB().y;
*/
/** Get the current motor torque, usually in N-m. */
public float getReferenceAngle () {
return jniGetReferenceAngle(addr);
}
private native float jniGetReferenceAngle (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetReferenceAngle();
*/
public float getMaxMotorTorque () {
return jniGetMaxMotorTorque(addr);
}
private native float jniGetMaxMotorTorque (long addr); /*
b2RevoluteJoint* joint = (b2RevoluteJoint*)addr;
return joint->GetMaxMotorTorque();
*/
}