public final class Quaternion extends java.lang.Object implements Savable, java.lang.Cloneable, java.io.Serializable
Quaternion
defines a single example of a more general class of
hypercomplex numbers. Quaternions extends a rotation in three dimensions to a
rotation in four dimensions. This avoids "gimbal lock" and allows for smooth
continuous rotation.
Quaternion
is defined by four floating point numbers: {x y z w}.Modifier and Type | Field and Description |
---|---|
static Quaternion |
DIRECTION_Z
another instance of the identity Quaternion (0, 0, 0, 1)
|
static Quaternion |
IDENTITY
Represents the identity quaternion rotation (0, 0, 0, 1).
|
protected float |
w
the W (real) component (not an angle!)
|
protected float |
x
the X component (not an angle!)
|
protected float |
y
the Y component (not an angle!)
|
protected float |
z
the Z component (not an angle!)
|
static Quaternion |
ZERO
The zero quaternion (0, 0, 0, 0) doesn't represent any rotation.
|
Constructor and Description |
---|
Quaternion()
Constructor instantiates a new
Quaternion object
initializing all values to zero, except w which is initialized to 1. |
Quaternion(float[] angles)
Instantiate a new
Quaternion from Tait-Bryan angles,
applying the rotations in x-z-y extrinsic order or y-z'-x" intrinsic
order. |
Quaternion(float x,
float y,
float z,
float w)
Constructor instantiates a new
Quaternion object from the
given list of parameters. |
Quaternion(Quaternion q)
Constructor instantiates a new
Quaternion object from an
existing quaternion, creating a copy. |
Quaternion(Quaternion q1,
Quaternion q2,
float interp)
Constructor instantiates a new
Quaternion object from an
interpolation between two other quaternions. |
Modifier and Type | Method and Description |
---|---|
Quaternion |
add(Quaternion q)
add adds the values of this quaternion to those of the
parameter quaternion. |
Quaternion |
addLocal(Quaternion q)
add adds the values of this quaternion to those of the
parameter quaternion. |
void |
apply(Matrix3f matrix)
apply multiplies this quaternion by a parameter matrix
internally. |
Quaternion |
clone()
Create a copy of this quaternion.
|
float |
dot(Quaternion q)
dot calculates and returns the dot product of this
quaternion with that of the parameter quaternion. |
boolean |
equals(java.lang.Object o)
equals determines if two quaternions are logically equal,
that is, if the values of (x, y, z, w) are the same for both quaternions. |
Quaternion |
fromAngleAxis(float angle,
Vector3f axis)
fromAngleAxis sets this quaternion to the values specified
by an angle and an axis of rotation. |
Quaternion |
fromAngleNormalAxis(float angle,
Vector3f axis)
fromAngleNormalAxis sets this quaternion to the values
specified by an angle and a normalized axis of rotation. |
Quaternion |
fromAngles(float[] angles)
Reconfigure this
Quaternion based on Tait-Bryan angles,
applying the rotations in x-z-y extrinsic order or y-z'-x" intrinsic
order. |
Quaternion |
fromAngles(float xAngle,
float yAngle,
float zAngle)
Reconfigure this Quaternion based on Tait-Bryan rotations, applying the
rotations in x-z-y extrinsic order or y-z'-x" intrinsic order.
|
Quaternion |
fromAxes(Vector3f[] axis)
fromAxes creates a Quaternion that
represents the coordinate system defined by three axes. |
Quaternion |
fromAxes(Vector3f xAxis,
Vector3f yAxis,
Vector3f zAxis)
fromAxes creates a Quaternion that
represents the coordinate system defined by three axes. |
Quaternion |
fromRotationMatrix(float m00,
float m01,
float m02,
float m10,
float m11,
float m12,
float m20,
float m21,
float m22)
Set this quaternion based on a rotation matrix with the specified
elements.
|
Quaternion |
fromRotationMatrix(Matrix3f matrix)
fromRotationMatrix generates a quaternion from a supplied
matrix. |
Vector3f |
getRotationColumn(int i)
getRotationColumn returns one of three columns specified
by the parameter. |
Vector3f |
getRotationColumn(int i,
Vector3f store)
getRotationColumn returns one of three columns specified
by the parameter. |
float |
getW()
Determine the W (real) component.
|
float |
getX()
Determine the X component.
|
float |
getY()
Determine the Y component.
|
float |
getZ()
Determine the Z component.
|
int |
hashCode()
hashCode returns the hash code value as an integer and is
supported for the benefit of hashing based collection classes such as
Hashtable, HashMap, HashSet etc. |
Quaternion |
inverse()
inverse returns the inverse of this quaternion as a new
quaternion. |
Quaternion |
inverseLocal()
inverse calculates the inverse of this quaternion and
returns this quaternion after it is calculated. |
boolean |
isIdentity() |
boolean |
isSimilar(Quaternion other,
float epsilon)
Returns true if this quaternion is similar to the specified quaternion
within some value of epsilon.
|
void |
loadIdentity()
Sets this Quaternion to {0, 0, 0, 1}.
|
Quaternion |
lookAt(Vector3f direction,
Vector3f up)
lookAt is a convenience method for auto-setting the
quaternion based on a direction and an up vector. |
Quaternion |
mult(float scalar)
mult multiplies this quaternion by a parameter scalar. |
Quaternion |
mult(Quaternion q)
mult multiplies this quaternion by a parameter quaternion. |
Quaternion |
mult(Quaternion q,
Quaternion res)
mult multiplies this quaternion by a parameter quaternion. |
Vector3f |
mult(Vector3f v)
mult multiplies this quaternion by a parameter vector. |
Vector3f |
mult(Vector3f v,
Vector3f store)
mult multiplies this quaternion by a parameter vector. |
Quaternion |
multLocal(float scalar)
mult multiplies this quaternion by a parameter scalar. |
Quaternion |
multLocal(float qx,
float qy,
float qz,
float qw)
Multiplies this Quaternion by the supplied quaternion.
|
Quaternion |
multLocal(Quaternion q)
Multiplies this Quaternion by the supplied quaternion.
|
Vector3f |
multLocal(Vector3f v)
mult multiplies this quaternion by a parameter vector. |
void |
negate()
Flip the signs of all components of this Quaternion.
|
void |
nlerp(Quaternion q2,
float blend)
Sets the values of this quaternion to the nlerp from itself to q2 by blend.
|
float |
norm()
norm returns the norm of this quaternion. |
Quaternion |
normalizeLocal()
normalize normalizes the current Quaternion . |
Quaternion |
opposite() |
Quaternion |
opposite(Quaternion store)
FIXME: This seems to have singularity type issues with angle == 0, possibly others such as PI.
|
Quaternion |
oppositeLocal() |
void |
read(JmeImporter e)
De-serialize this quaternion from the specified importer, for example
when loading from a J3O file.
|
void |
readExternal(java.io.ObjectInput in)
readExternal builds a quaternion from an
ObjectInput object. |
Quaternion |
set(float x,
float y,
float z,
float w)
sets the data in a
Quaternion object from the given list of
parameters. |
Quaternion |
set(Quaternion q)
Sets the data in this
Quaternion object to be equal to the
passed Quaternion object. |
void |
slerp(Quaternion q2,
float changeAmnt)
Sets the values of this quaternion to the slerp from itself to q2 by
changeAmnt
|
Quaternion |
slerp(Quaternion q1,
Quaternion q2,
float t)
slerp sets this quaternion's value as an interpolation
between two other quaternions. |
Quaternion |
subtract(Quaternion q)
subtract subtracts the values of the parameter quaternion
from those of this quaternion. |
Quaternion |
subtractLocal(Quaternion q)
subtract subtracts the values of the parameter quaternion
from those of this quaternion. |
float |
toAngleAxis(Vector3f axisStore)
toAngleAxis sets a given angle and axis to that
represented by the current quaternion. |
float[] |
toAngles(float[] angles)
Convert this
Quaternion to Tait-Bryan angles, to be applied
in x-z-y intrinsic order or y-z'-x" extrinsic order, for instance by
fromAngles(float[]) . |
void |
toAxes(Vector3f[] axes)
toAxes determines the axes of the coordinate system
described by this Quaternion. |
Matrix3f |
toRotationMatrix()
toRotationMatrix converts this quaternion to a rotational
matrix. |
Matrix3f |
toRotationMatrix(Matrix3f result)
toRotationMatrix converts this quaternion to a rotational
matrix. |
Matrix4f |
toRotationMatrix(Matrix4f result)
toRotationMatrix converts this quaternion to a rotational
matrix. |
java.lang.String |
toString()
toString returns a string representation of this
Quaternion . |
Matrix4f |
toTransformMatrix(Matrix4f store)
toTransformMatrix converts this quaternion to a transform
matrix. |
void |
write(JmeExporter e)
Serialize this quaternion to the specified exporter, for example when
saving to a J3O file.
|
void |
writeExternal(java.io.ObjectOutput out)
writeExternal writes this quaternion out to a
ObjectOutput object. |
public static final Quaternion IDENTITY
public static final Quaternion DIRECTION_Z
public static final Quaternion ZERO
protected float x
protected float y
protected float z
protected float w
public Quaternion()
Quaternion
object
initializing all values to zero, except w which is initialized to 1.public Quaternion(float x, float y, float z, float w)
Quaternion
object from the
given list of parameters.x
- the x value of the quaternion.y
- the y value of the quaternion.z
- the z value of the quaternion.w
- the w value of the quaternion.public Quaternion(float[] angles)
Quaternion
from Tait-Bryan angles,
applying the rotations in x-z-y extrinsic order or y-z'-x" intrinsic
order.angles
- an array of Tait-Bryan angles (in radians, exactly 3
elements, the X angle in angles[0], the Y angle in angles[1], and the Z
angle in angles[2], unaffected)public Quaternion(Quaternion q1, Quaternion q2, float interp)
Quaternion
object from an
interpolation between two other quaternions.q1
- the first quaternion.q2
- the second quaternion.interp
- the amount to interpolate between the two quaternions.public Quaternion(Quaternion q)
Quaternion
object from an
existing quaternion, creating a copy.q
- the quaternion to copy.public float getX()
public float getY()
public float getZ()
public float getW()
public Quaternion set(float x, float y, float z, float w)
Quaternion
object from the given list of
parameters.x
- the x value of the quaternion.y
- the y value of the quaternion.z
- the z value of the quaternion.w
- the w value of the quaternion.public Quaternion set(Quaternion q)
Quaternion
object to be equal to the
passed Quaternion
object. The values are copied producing
a new object.q
- The Quaternion to copy values from.public void loadIdentity()
public boolean isIdentity()
public Quaternion fromAngles(float[] angles)
Quaternion
based on Tait-Bryan angles,
applying the rotations in x-z-y extrinsic order or y-z'-x" intrinsic
order.angles
- an array of Tait-Bryan angles (in radians, exactly 3
elements, the X angle in angles[0], the Y angle in angles[1], and the Z
angle in angles[2], unaffected)public Quaternion fromAngles(float xAngle, float yAngle, float zAngle)
xAngle
- the X angle (in radians)yAngle
- the Y angle (in radians)zAngle
- the Z angle (in radians)public float[] toAngles(float[] angles)
Quaternion
to Tait-Bryan angles, to be applied
in x-z-y intrinsic order or y-z'-x" extrinsic order, for instance by
fromAngles(float[])
.
Note that the result is not always 100% accurate due to the implications
of Tait-Bryan angles.angles
- an array of 3 floats in which to store the result, or else
null (If null, a new array will be allocated.)public Quaternion fromRotationMatrix(Matrix3f matrix)
fromRotationMatrix
generates a quaternion from a supplied
matrix. This matrix is assumed to be a rotational matrix.matrix
- the matrix that defines the rotation.public Quaternion fromRotationMatrix(float m00, float m01, float m02, float m10, float m11, float m12, float m20, float m21, float m22)
m00
- the matrix element in row 0, column 0m01
- the matrix element in row 0, column 1m02
- the matrix element in row 0, column 2m10
- the matrix element in row 1, column 0m11
- the matrix element in row 1, column 1m12
- the matrix element in row 1, column 2m20
- the matrix element in row 2, column 0m21
- the matrix element in row 2, column 1m22
- the matrix element in row 2, column 2public Matrix3f toRotationMatrix()
toRotationMatrix
converts this quaternion to a rotational
matrix. Note: the result is created from a normalized version of this quat.public Matrix3f toRotationMatrix(Matrix3f result)
toRotationMatrix
converts this quaternion to a rotational
matrix. The result is stored in result.result
- The Matrix3f to store the result in.public Matrix4f toTransformMatrix(Matrix4f store)
toTransformMatrix
converts this quaternion to a transform
matrix. The result is stored in result.
Note this method won't preserve the scale of the given matrix.store
- The Matrix3f to store the result in.public Matrix4f toRotationMatrix(Matrix4f result)
toRotationMatrix
converts this quaternion to a rotational
matrix. The result is stored in result. 4th row and 4th column values are
untouched. Note: the result is created from a normalized version of this quat.
Note that this method will preserve the scale of the given matrixresult
- The Matrix4f to store the result in.public Vector3f getRotationColumn(int i)
getRotationColumn
returns one of three columns specified
by the parameter. This column is returned as a Vector3f
object.i
- the column to retrieve. Must be between 0 and 2.public Vector3f getRotationColumn(int i, Vector3f store)
getRotationColumn
returns one of three columns specified
by the parameter. This column is returned as a Vector3f
object. The value is retrieved as if this quaternion was first normalized.i
- the column to retrieve. Must be between 0 and 2.store
- the vector object to store the result in. if null, a new one
is created.public Quaternion fromAngleAxis(float angle, Vector3f axis)
fromAngleAxis
sets this quaternion to the values specified
by an angle and an axis of rotation. This method creates an object, so
use fromAngleNormalAxis if your axis is already normalized.angle
- the angle to rotate (in radians).axis
- the axis of rotation.public Quaternion fromAngleNormalAxis(float angle, Vector3f axis)
fromAngleNormalAxis
sets this quaternion to the values
specified by an angle and a normalized axis of rotation.angle
- the angle to rotate (in radians).axis
- the axis of rotation (already normalized).public float toAngleAxis(Vector3f axisStore)
toAngleAxis
sets a given angle and axis to that
represented by the current quaternion. The values are stored as
follows: The axis is provided as a parameter and built by the method,
the angle is returned as a float.axisStore
- the object we'll store the computed axis in.public Quaternion slerp(Quaternion q1, Quaternion q2, float t)
slerp
sets this quaternion's value as an interpolation
between two other quaternions.q1
- the first quaternion.q2
- the second quaternion.t
- the amount to interpolate between the two quaternions.public void slerp(Quaternion q2, float changeAmnt)
q2
- Final interpolation valuechangeAmnt
- The amount differencepublic void nlerp(Quaternion q2, float blend)
q2
- the desired final value when blend=1 (not null, unaffected)blend
- the fractional weight applied to q2 (0→this, 1→q2)public Quaternion add(Quaternion q)
add
adds the values of this quaternion to those of the
parameter quaternion. The result is returned as a new quaternion.q
- the quaternion to add to this.public Quaternion addLocal(Quaternion q)
add
adds the values of this quaternion to those of the
parameter quaternion. The result is stored in this Quaternion.q
- the quaternion to add to this.public Quaternion subtract(Quaternion q)
subtract
subtracts the values of the parameter quaternion
from those of this quaternion. The result is returned as a new
quaternion.q
- the quaternion to subtract from this.public Quaternion subtractLocal(Quaternion q)
subtract
subtracts the values of the parameter quaternion
from those of this quaternion. The result is stored in this Quaternion.q
- the quaternion to subtract from this.public Quaternion mult(Quaternion q)
mult
multiplies this quaternion by a parameter quaternion.
The result is returned as a new quaternion. It should be noted that
quaternion multiplication is not commutative so q * p != p * q.q
- the quaternion to multiply this quaternion by.public Quaternion mult(Quaternion q, Quaternion res)
mult
multiplies this quaternion by a parameter quaternion.
The result is returned as a new quaternion. It should be noted that
quaternion multiplication is not commutative so q * p != p * q.
It IS safe for q and res to be the same object.
It IS NOT safe for this and res to be the same object.q
- the quaternion to multiply this quaternion by.res
- the quaternion to store the result in.public void apply(Matrix3f matrix)
apply
multiplies this quaternion by a parameter matrix
internally.matrix
- the matrix to apply to this quaternion.public Quaternion fromAxes(Vector3f[] axis)
fromAxes
creates a Quaternion
that
represents the coordinate system defined by three axes. These axes are
assumed to be orthogonal and no error checking is applied. Thus, the user
must insure that the three axes being provided indeed represents a proper
right handed coordinate system.axis
- the array containing the three vectors representing the
coordinate system.public Quaternion fromAxes(Vector3f xAxis, Vector3f yAxis, Vector3f zAxis)
fromAxes
creates a Quaternion
that
represents the coordinate system defined by three axes. These axes are
assumed to be orthogonal and no error checking is applied. Thus, the user
must insure that the three axes being provided indeed represents a proper
right handed coordinate system.xAxis
- vector representing the x-axis of the coordinate system.yAxis
- vector representing the y-axis of the coordinate system.zAxis
- vector representing the z-axis of the coordinate system.public void toAxes(Vector3f[] axes)
toAxes
determines the axes of the coordinate system
described by this Quaternion.axes
- an array to store the results (not null, length=3, modified)public Vector3f mult(Vector3f v)
mult
multiplies this quaternion by a parameter vector. The
result is returned as a new vector.v
- the vector to multiply this quaternion by.public Vector3f multLocal(Vector3f v)
mult
multiplies this quaternion by a parameter vector. The
result is stored in the supplied vectorv
- the vector to multiply this quaternion by.public Quaternion multLocal(Quaternion q)
q
- The Quaternion to multiply this one by.public Quaternion multLocal(float qx, float qy, float qz, float qw)
qx
- quat x valueqy
- quat y valueqz
- quat z valueqw
- quat w valuepublic Vector3f mult(Vector3f v, Vector3f store)
mult
multiplies this quaternion by a parameter vector. The
result is returned as a new vector.v
- the vector to multiply this quaternion by.store
- the vector to store the result in. It IS safe for v and store
to be the same object.public Quaternion mult(float scalar)
mult
multiplies this quaternion by a parameter scalar. The
result is returned as a new quaternion.scalar
- the scalar to multiply this quaternion by.public Quaternion multLocal(float scalar)
mult
multiplies this quaternion by a parameter scalar. The
result is stored locally.scalar
- the scalar to multiply this quaternion by.public float dot(Quaternion q)
dot
calculates and returns the dot product of this
quaternion with that of the parameter quaternion.q
- the quaternion to calculate the dot product of.public float norm()
norm
returns the norm of this quaternion. This is the dot
product of this quaternion with itself.public Quaternion normalizeLocal()
normalize
normalizes the current Quaternion
.
The result is stored internally.public Quaternion inverse()
inverse
returns the inverse of this quaternion as a new
quaternion. If this quaternion does not have an inverse (if its normal is
0 or less), then null is returned.public Quaternion inverseLocal()
inverse
calculates the inverse of this quaternion and
returns this quaternion after it is calculated. If this quaternion does
not have an inverse (if its normal is 0 or less), nothing happenspublic void negate()
public java.lang.String toString()
toString
returns a string representation of this
Quaternion
. The format is:
(X.XXXX, Y.YYYY, Z.ZZZZ, W.WWWW)toString
in class java.lang.Object
Object.toString()
public boolean equals(java.lang.Object o)
equals
determines if two quaternions are logically equal,
that is, if the values of (x, y, z, w) are the same for both quaternions.equals
in class java.lang.Object
o
- the object to compare for equalitypublic boolean isSimilar(Quaternion other, float epsilon)
other
- the Quaternion to compare with (not null, unaffected)epsilon
- the error tolerance for each componentpublic int hashCode()
hashCode
returns the hash code value as an integer and is
supported for the benefit of hashing based collection classes such as
Hashtable, HashMap, HashSet etc.hashCode
in class java.lang.Object
Object.hashCode()
public void readExternal(java.io.ObjectInput in) throws java.io.IOException
readExternal
builds a quaternion from an
ObjectInput
object. in
- the ObjectInput value to read from.java.io.IOException
- if the ObjectInput value has problems reading a float.Externalizable
public void writeExternal(java.io.ObjectOutput out) throws java.io.IOException
writeExternal
writes this quaternion out to a
ObjectOutput
object. NOTE: Used with serialization. Not to
be called manually.out
- the object to write to.java.io.IOException
- if writing to the ObjectOutput fails.Externalizable
public Quaternion lookAt(Vector3f direction, Vector3f up)
lookAt
is a convenience method for auto-setting the
quaternion based on a direction and an up vector. It computes
the rotation to transform the z-axis to point into 'direction'
and the y-axis to 'up'. Note that the results will be invalid
if a zero length direction vector (0,0,0) is supplied, or if the
direction and up vectors are parallel.direction
- where to look at in terms of local coordinatesup
- a vector indicating the local up direction.
(typically {0, 1, 0} in jME.)public void write(JmeExporter e) throws java.io.IOException
public void read(JmeImporter e) throws java.io.IOException
public Quaternion opposite()
public Quaternion opposite(Quaternion store)
store
- A Quaternion to store our result in. If null, a new one is
created.public Quaternion oppositeLocal()
public Quaternion clone()
clone
in class java.lang.Object