D3DXQuaternionLn function (D3dx9math.h)
Note
The D3DX utility library is deprecated. We recommend that you use DirectXMath instead.
Calculates the natural logarithm.
Syntax
D3DXQUATERNION* D3DXQuaternionLn(
_Inout_ D3DXQUATERNION *pOut,
_In_ const D3DXQUATERNION *pQ
);
Parameters
-
pOut [in, out]
-
Type: D3DXQUATERNION*
Pointer to the D3DXQUATERNION structure that is the result of the operation.
-
pQ [in]
-
Type: const D3DXQUATERNION*
Pointer to the source D3DXQUATERNION structure.
Return value
Type: D3DXQUATERNION*
Pointer to a D3DXQUATERNION structure that is the natural logarithm.
Remarks
The D3DXQuaternionLn function works only for unit quaternions.
A unit quaternion, is defined by:
Q == (cos(theta), sin(theta) * v) where |v| = 1
The natural logarithm of Q is, ln(Q) = (0, theta * v)
The return value for this function is the same value returned in the pOut parameter. In this way, the D3DXQuaternionLn function can be used as a parameter for another function.
Use D3DXQuaternionNormalize for any quaternion input that is not already normalized.
Requirements
| Requirement | Value |
|---|---|
| Header |
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| Library |
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See also