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/*
 * Copyright (c) 2009-2018 jMonkeyEngine
 * All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
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 *   may be used to endorse or promote products derived from this software
 *   without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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package com.jme3.bullet.joints;

import com.jme3.bullet.objects.PhysicsRigidBody;
import com.jme3.math.Matrix3f;
import com.jme3.math.Vector3f;

/**
 * A 6 degree-of-freedom joint based on Bullet's btGeneric6DofSpringConstraint.
 * 
 * From the Bullet manual:

 * This generic constraint can emulate a variety of standard constraints, by
 * configuring each of the 6 degrees of freedom (dof). The first 3 dof axis are
 * linear axis, which represent translation of rigidbodies, and the latter 3 dof
 * axis represent the angular motion. Each axis can be either locked, free or
 * limited. On construction of a new btGeneric6DofSpring2Constraint, all axis
 * are locked. Afterwards the axis can be reconfigured. Note that several
 * combinations that include free and/or limited angular degrees of freedom are
 * undefined.
 * 

 * For each axis:

 * Lowerlimit = Upperlimit → axis is locked
 * Lowerlimit > Upperlimit → axis is free
 * Lowerlimit < Upperlimit → axis it limited in that range
 * 
 *
 * @author normenhansen
 */
public class SixDofSpringJoint extends SixDofJoint {

   final boolean       springEnabled[] = new boolean[6];
   final float equilibriumPoint[] = new float[6];
   final float springStiffness[] = new float[6];
   final float springDamping[] = new float[6]; // between 0 and 1 (1 == no damping)

    /**
     * No-argument constructor needed by SavableClassUtil. Do not invoke
     * directly!
     */
    public SixDofSpringJoint() {
    }

    /**
     * Instantiate a SixDofSpringJoint. To be effective, the joint must be added
     * to a physics space.
     *
     * @param nodeA the 1st body connected by the joint (not null, alias
     * created)
     * @param nodeB the 2nd body connected by the joint (not null, alias
     * created)
     * @param pivotA the local offset of the connection point in node A (not
     * null, alias created)
     * @param pivotB the local offset of the connection point in node B (not
     * null, alias created)
     * @param rotA the local orientation of the connection to node A (not
     * null, alias created)
     * @param rotB the local orientation of the connection to node B (not
     * null, alias created)
     * @param useLinearReferenceFrameA true→use node A, false→use node
     * B
     */
    public SixDofSpringJoint(PhysicsRigidBody nodeA, PhysicsRigidBody nodeB, Vector3f pivotA, Vector3f pivotB, Matrix3f rotA, Matrix3f rotB, boolean useLinearReferenceFrameA) {
        super(nodeA, nodeB, pivotA, pivotB, rotA, rotB, useLinearReferenceFrameA);
    }

    /**
     * Enable or disable the spring for the indexed degree of freedom.
     *
     * @param index which degree of freedom (≥0, <6)
     * @param onOff true → enable, false → disable
     */
    public void enableSpring(int index, boolean onOff) {
        enableSpring(objectId, index, onOff);
    }
    native void enableSpring(long objctId, int index, boolean onOff);

    /**
     * Alter the spring stiffness for the indexed degree of freedom.
     *
     * @param index which degree of freedom (≥0, <6)
     * @param stiffness the desired stiffness
     */
    public void setStiffness(int index, float stiffness) {
        setStiffness(objectId, index, stiffness);
    }
    native void setStiffness(long objctId, int index, float stiffness);

    /**
     * Alter the damping for the indexed degree of freedom.
     *
     * @param index which degree of freedom (≥0, <6)
     * @param damping the desired viscous damping ratio (0→no damping,
     * 1→critically damped, default=1)
     */
    public void setDamping(int index, float damping) {
        setDamping(objectId, index, damping);

    }
    native void setDamping(long objctId, int index, float damping);
    /**
     * Alter the equilibrium points for all degrees of freedom, based on the
     * current constraint position/orientation.
     */
    public void setEquilibriumPoint() { // set the current constraint position/orientation as an equilibrium point for all DOF
        setEquilibriumPoint(objectId);
    }
    native void setEquilibriumPoint(long objctId);
    /**
     * Alter the equilibrium point of the indexed degree of freedom, based on
     * the current constraint position/orientation.
     *
     * @param index which degree of freedom (≥0, <6)
     */
    public void setEquilibriumPoint(int index){ // set the current constraint position/orientation as an equilibrium point for given DOF
        setEquilibriumPoint(objectId, index);
    }
    native void setEquilibriumPoint(long objctId, int index);
    @Override
    native long createJoint(long objectIdA, long objectIdB, Vector3f pivotA, Matrix3f rotA, Vector3f pivotB, Matrix3f rotB, boolean useLinearReferenceFrameA);

}