D3DXQuaternionExp

Calculates the exponential.

D3DXQUATERNION * D3DXQuaternionExp(
  D3DXQUATERNION * pOut,
  CONST D3DXQUATERNION * pQ
);

Parameters

pOut

[in, out] Pointer to the D3DXQUATERNION structure that is the result of the operation.

pQ

[in] Pointer to the source D3DXQUATERNION structure.

Return Values

Pointer to a D3DXQUATERNION structure that is the exponential.

Remarks

This method converts a pure quaternion to a unit quaternion. D3DXQuaternionExp expects a pure quaternion, where w is ignored in the calculation (w == 0).

Given a pure quaternion defined by:
q = (0, theta * v); 
    
This method calculates the exponential result.
exp(Q) = (cos(theta), sin(theta) * v)

where v is the vector portion of a quaternion.

The return value for this function is the same value returned in the pOut parameter. In this way, the D3DXQuaternionExp function can be used as a parameter for another function.

The D3DXQuaternionSquadSetup method can also be used to set up the control points of a quaternion.

Use D3DXQuaternionNormalize for any quaternion input that is not already normalized.

Requirements

Header: Declared in D3dx9math.h.

See Also

D3DXQuaternionLn, D3DXQuaternionSquad