Class PositionPathInterpolator


  • public class PositionPathInterpolator
    extends PathInterpolator
    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.
    • Constructor Detail

      • PositionPathInterpolator

        public PositionPathInterpolator​(Alpha alpha,
                                        TransformGroup target,
                                        Transform3D axisOfTransform,
                                        float[] knots,
                                        javax.vecmath.Point3f[] positions)
        Constructs a new PositionPathInterpolator that varies the transform of the target TransformGroup.
        Parameters:
        alpha - the alpha object for this interpolator
        target - the TransformGroup node affected by this translator
        axisOfTransform - the transform that defines the local coordinate system in which this interpolator operates
        knots - an array of knot values that specify interpolation points.
        positions - an array of position values at the knots.
        Throws:
        java.lang.IllegalArgumentException - if the lengths of the knots and positions arrays are not the same.
    • Method Detail

      • setPosition

        public void setPosition​(int index,
                                javax.vecmath.Point3f position)
        Sets the position at the specified index for this interpolator.
        Parameters:
        index - the index of the position to be changed
        position - the new position at the index
      • getPosition

        public void getPosition​(int index,
                                javax.vecmath.Point3f position)
        Retrieves the position value at the specified index.
        Parameters:
        index - the index of the value requested
        position - the variable to receive the position value at the specified index
      • setPathArrays

        public void setPathArrays​(float[] knots,
                                  javax.vecmath.Point3f[] positions)
        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.
        Parameters:
        knots - a new array of knot values that specify interpolation points
        positions - a new array of position values at the knots
        Throws:
        java.lang.IllegalArgumentException - if the lengths of the knots and positions arrays are not the same.
        Since:
        Java 3D 1.2
      • getPositions

        public void getPositions​(javax.vecmath.Point3f[] positions)
        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.
        Parameters:
        positions - array that will receive the positions
        Since:
        Java 3D 1.2
      • setAxisOfTranslation

        public void setAxisOfTranslation​(Transform3D axisOfTranslation)
        Deprecated.
        As of Java 3D version 1.3, replaced by TransformInterpolator.setTransformAxis(Transform3D)
      • getAxisOfTranslation

        public Transform3D getAxisOfTranslation()
        Deprecated.
        As of Java 3D version 1.3, replaced by TransformInterpolator.getTransformAxis()
      • computeTransform

        public void computeTransform​(float alphaValue,
                                     Transform3D transform)
        Computes the new transform for this interpolator for a given alpha value.
        Specified by:
        computeTransform in class TransformInterpolator
        Parameters:
        alphaValue - alpha value between 0.0 and 1.0
        transform - object that receives the computed transform for the specified alpha value
        Since:
        Java 3D 1.3