Package com.openinventor.inventor

Class SbRotationd

java.lang.Object
com.openinventor.inventor.SbBasic
com.openinventor.inventor.SbRotationd
public class SbRotationd extends SbBasic
Class for representing a rotation (double precision). Object that stores a rotation using double precision values. Although Open Inventor fields still store only single precision values, for certain applications it is useful and convenient to be able to store and manipulate double precision values, for example, double precision coordinate data or values that will be used for further computation.

The rotation value is stored internally as a quaternion. Quaternion representation is more compact, faster to compute and more numerically stable than rotation matrices. Quaternion representation allows smooth rotation (spherical linear interpolation) and avoids the problem of "gimbal lock" associated with Euler angles. It is not necessary to deal directly with quaternions. Many convenience methods are provided to set and get rotations using matrix and axis/angle representations.

Rotations are most commonly specified using an axis and an angle in radians. A common mistake is to use the constructor or setValue method that takes four double values, when intending to set an axis and angle. The methods that take four double values directly specify the quaternion value, which is probably not the intended result. For example: 

 // Create a rotation of PI/2 radians around the Z axis:
 
 // Incorrect.
 // (Compiles, but actually sets the quaternion value directly!)
 SbRotationd rotation1 = new SbRotationd(0, 0, 1, 1.5707963);
 
 // This is the correct rotation.
 SbRotationd rotation2 = new SbRotationd(new SbVec3d(0, 0, 1), 1.5707963);

See Also:

  • Field Details

    • array

      public final double[] array

  • Constructor Details

    • SbRotationd

      public SbRotationd(SbRotationd copyFrom)

    • SbRotationd

      public SbRotationd(double[] components)

    • SbRotationd

      public SbRotationd(double q0, double q1, double q2, double q3)
      Constructor. The constructors that take four doubles create a quaternion from those doubles (careful, this differs from the four numbers in an axis/radian definition).

    • SbRotationd

      public SbRotationd()
      Constructor for rotation. The initial value is no rotation.

    • SbRotationd

      public SbRotationd(SbMatrixd m)
      Constructor. The matrix constructor requires a valid rotation matrix.

    • SbRotationd

      public SbRotationd(SbMatrix3 m)
      Constructor. The matrix constructor requires a valid 3x3 rotation matrix.

    • SbRotationd

      public SbRotationd(SbVec3d axis, double radians)
      Constructor. The axis/radians constructor creates a rotation of angle radians about the given axis.

    • SbRotationd

      public SbRotationd(SbVec3d rotateFrom, SbVec3d rotateTo)
      Constructor. The rotateFrom/To constructor defines rotation that rotates from one vector into another. The rotateFrom and rotateTo vectors are normalized by the constructor before calculating the rotation.

  • Method Details

    • setValue

      public SbRotationd setValue(double[] components)

    • getValue

      public double[] getValue()

    • setValue

      public SbRotationd setValue(double[] components, int startIndex)

    • setValue

      public void setValue(SbRotationd copyFrom)

    • scaleAngle

      public void scaleAngle(double scaleFactor)
      Keep the axis the same. Multiply the angle of rotation by the amount scaleFactor.

    • multVec

      public SbVec3d multVec(SbVec3d src)
      Multiplies the given vector by the matrix of this rotation.

    • times

      public SbRotationd times(SbRotationd q2)
      Multiplication of two rotations; results in product of rotations.

    • identity

      public static SbRotationd identity()
      Returns a null rotation.

    • toArray

      public static SbRotationd[] toArray(long nativeArray, long length)

    • setValue

      public SbRotationd setValue(double q0, double q1, double q2, double q3)
      Sets value of rotation from 4 individual components of a quaternion.

    • slerp

      public static SbRotationd slerp(SbRotationd rot0, SbRotationd rot1, double t)
      Spherical linear interpolation: as t goes from 0 to 1, returned value goes from rot0 to rot1.

    • getMatrixd

      public SbMatrixd getMatrixd()
      Returns corresponding 4x4 rotation matrix.

    • setValue

      public SbRotationd setValue(SbVec3d axis, double radians)
      Sets value of vector from 3D rotation axis vector and angle in radians.

    • decompose

      public SbRotationd.AxisAngle decompose()
      Returns corresponding 3D rotation axis vector and angle in radians.

    • setValue

      public SbRotationd setValue(SbVec3d rotateFrom, SbVec3d rotateTo)
      Sets rotation to rotate one direction vector to another. The rotateFrom and rotateTo arguments are normalized before the rotation is calculated.

    • getMatrix

      public SbMatrix getMatrix()
      Returns corresponding 4x4 rotation matrix.

    • invert

      public SbRotationd invert()
      Changes a rotation to be its inverse.

    • inverse

      public SbRotationd inverse()
      Returns the inverse of a rotation.

    • setValue

      public SbRotationd setValue(SbMatrixd m)
      Sets value of rotation from a rotation matrix.

    • getMatrix3

      public SbMatrix3 getMatrix3()
      Returns corresponding 3x3 rotation matrix.

    • setValue

      public SbRotationd setValue(SbRotation rotate)
      Sets rotation from a single precision rotation.

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object

    • equals

      public boolean equals(SbRotationd r, double tolerance)
      Equality comparison within given tolerance - the square of the length of the maximum distance between the two quaternion vectors.

    • setValue

      public SbRotationd setValue(SbMatrix3 m)
      Sets rotation from a 3x3 rotation matrix.

    • setValue

      public SbRotationd setValue(SbMatrix m)
      Sets rotation from a single precision rotation matrix.

    • multiply

      public void multiply(SbRotationd q)
      Multiplies by another rotation; results in product of rotations.