javax.media.j3d.PositionPathInterpolator Maven / Gradle / Ivy
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* Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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package javax.media.j3d;
import javax.vecmath.Point3f;
import javax.vecmath.Vector3f;
/**
* PositionPathInterpolator behavior. This class defines a behavior
* that modifies the translational component of its target TransformGroup
* by linearly interpolating among a series of predefined knot/position
* pairs (using the value generated by the specified Alpha object). The
* interpolated position is used to generate a translation transform
* in the local coordinate system of this interpolator. The first knot
* must have a value of 0.0. The last knot must have a value of 1.0. An
* intermediate knot with index k must have a value strictly greater
* than any knot with index less than k.
*/
public class PositionPathInterpolator extends PathInterpolator {
private Transform3D position = new Transform3D();
private Vector3f pos = new Vector3f();
// Array of positions at each knot
private Point3f positions[];
private float prevInterpolationValue = Float.NaN;
// We can't use a boolean flag since it is possible
// that after alpha change, this procedure only run
// once at alpha.finish(). So the best way is to
// detect alpha value change.
private float prevAlphaValue = Float.NaN;
private WakeupCriterion passiveWakeupCriterion = new WakeupOnElapsedFrames(0, true);
// non-public, default constructor used by cloneNode
PositionPathInterpolator() {
}
/**
* Constructs a new PositionPathInterpolator that varies the transform
* of the target TransformGroup.
* @param alpha the alpha object for this interpolator
* @param target the TransformGroup node affected by this translator
* @param axisOfTransform the transform that defines the local
* coordinate system in which this interpolator operates
* @param knots an array of knot values that specify interpolation points.
* @param positions an array of position values at the knots.
* @exception IllegalArgumentException if the lengths of the
* knots and positions arrays are not the same.
*/
public PositionPathInterpolator(Alpha alpha,
TransformGroup target,
Transform3D axisOfTransform,
float[] knots,
Point3f[] positions) {
super(alpha, target, axisOfTransform, knots);
if (knots.length != positions.length)
throw new IllegalArgumentException(J3dI18N.getString("PositionPathInterpolator0"));
setPathArrays(positions);
}
/**
* Sets the position at the specified index for this
* interpolator.
* @param index the index of the position to be changed
* @param position the new position at the index
*/
public void setPosition(int index, Point3f position) {
this.positions[index].set(position);
}
/**
* Retrieves the position value at the specified index.
* @param index the index of the value requested
* @param position the variable to receive the position value at
* the specified index
*/
public void getPosition(int index, Point3f position) {
position.set(this.positions[index]);
}
/**
* Replaces the existing arrays of knot values
* and position values with the specified arrays.
* The arrays of knots and positions are copied
* into this interpolator object.
* @param knots a new array of knot values that specify
* interpolation points
* @param positions a new array of position values at the knots
* @exception IllegalArgumentException if the lengths of the
* knots and positions arrays are not the same.
*
* @since Java 3D 1.2
*/
public void setPathArrays(float[] knots,
Point3f[] positions) {
if (knots.length != positions.length)
throw new IllegalArgumentException(J3dI18N.getString("PositionPathInterpolator0"));
setKnots(knots);
setPathArrays(positions);
}
// Set the specific arrays for this path interpolator
private void setPathArrays(Point3f[] positions) {
this.positions = new Point3f[positions.length];
for(int i = 0; i < positions.length; i++) {
this.positions[i] = new Point3f();
this.positions[i].set(positions[i]);
}
}
/**
* Copies the array of position values from this interpolator
* into the specified array.
* The array must be large enough to hold all of the positions.
* The individual array elements must be allocated by the caller.
* @param positions array that will receive the positions
*
* @since Java 3D 1.2
*/
public void getPositions(Point3f[] positions) {
for (int i = 0; i < this.positions.length; i++) {
positions[i].set(this.positions[i]);
}
}
/**
* @deprecated As of Java 3D version 1.3, replaced by
* TransformInterpolator.setTransformAxis(Transform3D)
*/
public void setAxisOfTranslation(Transform3D axisOfTranslation) {
setTransformAxis(axisOfTranslation);
}
/**
* @deprecated As of Java 3D version 1.3, replaced by
* TransformInterpolator.getTransformAxis()
*/
public Transform3D getAxisOfTranslation() {
return getTransformAxis();
}
/**
* Computes the new transform for this interpolator for a given
* alpha value.
*
* @param alphaValue alpha value between 0.0 and 1.0
* @param transform object that receives the computed transform for
* the specified alpha value
*
* @since Java 3D 1.3
*/
@Override
public void computeTransform(float alphaValue, Transform3D transform) {
computePathInterpolation(alphaValue);
if (currentKnotIndex == 0 &&
currentInterpolationValue == 0f) {
pos.x = positions[0].x;
pos.y = positions[0].y;
pos.z = positions[0].z;
} else {
pos.x = positions[currentKnotIndex].x +
(positions[currentKnotIndex+1].x -
positions[currentKnotIndex].x) * currentInterpolationValue;
pos.y = positions[currentKnotIndex].y +
(positions[currentKnotIndex+1].y -
positions[currentKnotIndex].y) * currentInterpolationValue;
pos.z = positions[currentKnotIndex].z +
(positions[currentKnotIndex+1].z -
positions[currentKnotIndex].z) * currentInterpolationValue;
}
position.setIdentity();
position.setTranslation(pos);
// construct a Transform3D from: axis * position * axisInverse
transform.mul(axis, position);
transform.mul(transform, axisInverse);
}
/**
* Used to create a new instance of the node. This routine is called
* by cloneTree to duplicate the current node.
* @param forceDuplicate when set to true, causes the
* duplicateOnCloneTree flag to be ignored. When
* false, the value of each node's
* duplicateOnCloneTree variable determines whether
* NodeComponent data is duplicated or copied.
*
* @see Node#cloneTree
* @see Node#cloneNode
* @see Node#duplicateNode
* @see NodeComponent#setDuplicateOnCloneTree
*/
@Override
public Node cloneNode(boolean forceDuplicate) {
PositionPathInterpolator ppi = new PositionPathInterpolator();
ppi.duplicateNode(this, forceDuplicate);
return ppi;
}
/**
* Copies all PositionPathInterpolator information from
* originalNode into
* the current node. This method is called from the
* cloneNode method which is, in turn, called by the
* cloneTree method.
*
* @param originalNode the original node to duplicate.
* @param forceDuplicate when set to true, causes the
* duplicateOnCloneTree flag to be ignored. When
* false, the value of each node's
* duplicateOnCloneTree variable determines whether
* NodeComponent data is duplicated or copied.
*
* @exception RestrictedAccessException if this object is part of a live
* or compiled scenegraph.
*
* @see Node#duplicateNode
* @see Node#cloneTree
* @see NodeComponent#setDuplicateOnCloneTree
*/
@Override
void duplicateAttributes(Node originalNode, boolean forceDuplicate) {
super.duplicateAttributes(originalNode, forceDuplicate);
PositionPathInterpolator pi =
(PositionPathInterpolator) originalNode;
int len = pi.getArrayLengths();
// No API available to set the size of positions
positions = new Point3f[len];
Point3f dupPoint = new Point3f();
for (int i = 0; i < len; i++) {
positions[i] = new Point3f();
pi.getPosition(i, dupPoint);
setPosition(i, dupPoint);
}
}
}