return true if the Quat represents a zero rotation, and therefore can be ignored in computations.

Length of the quaternion = sqrt(vec . vec)

Length of the quaternion = vec . vec.

Conjugate.

Multiplicative inverse method.

q^(-1) = q^

a quaternion which will perform a rotation of an angle around the axis given by the vector(x,y,z).

Define Spherical Linear interpolation method also

Set the elements of the Quat to represent a rotation of angle (degrees) around the axis (x,y,z)

Make a rotation Quat which will rotate vec1 to vec2. Generally take a dot product to get the angle between these and then use a cross product to get the rotation axis Watch out for the two special cases when the vectors are co-incident or opposite in direction.

Make a rotation Quat which will rotate vec1 to vec2

This routine uses only fast geometric transforms, without costly acos/sin computations. It's exact, fast, and with less degenerate cases than the acos/sin method.

For an explanation of the math used, you may see for example: http://logiciels.cnes.fr/MARMOTTES/marmottes-mathematique.pdf

Note

This is the rotation with shortest angle, which is the one equivalent to the acos/sin transform method. Other rotations exists, for example to additionally keep a local horizontal attitude.

Author

Nicolas Brodu

Return the angle and vector components represented by the quaternion.

Calculate and return the rotation as euler angles.

Spherical Linear Interpolation.

As t goes from 0 to 1, the Quat object goes from "from" to "to".

Spherical Linear Interpolation As t goes from 0 to 1, the Quat object goes from "from" to "to" Reference: Shoemake at SIGGRAPH 89 See also http://www.gamasutra.com/features/programming/19980703/quaternions_01.htm

Multiply by scalar.

Binary multiply.

Rotate a vector by this quaternion.

Unary multiply by scalar.

Unary multiply.

Divide by scalar.

Binary divide.

Unary divide by scalar.

Unary divide.

Binary addition.

Unary addition.

Unary subtraction.

Binary subtraction.

returns the negative of the quaternion. calls operator -() on the Vec4