# XMVector4Normalize function

Returns the normalized version of a 4D vector.

## Syntax

``````XMVECTOR XM_CALLCONV XMVector4Normalize(
FXMVECTOR V
);
``````

`V`

4D vector.

## Return Value

Returns the normalized version of V.

## Remarks

For a vector of length 0, this function returns a zero vector. For a vector with infinite length, it returns a vector of QNaN.

Note that for most graphics applications, ensuring the vectors have well-defined lengths that don't cause problems for normalization is common practice. However, if you need a robust normalization that works for all floating-point inputs, you can use the following code instead:

``````
inline XMVECTOR XMVector4NormalizeRobust( FXMVECTOR V )
{
// Compute the maximum absolute value component.
XMVECTOR vAbs = XMVectorAbs(V);
XMVECTOR max0 = XMVectorSplatX(vAbs);
XMVECTOR max1 = XMVectorSplatY(vAbs);
XMVECTOR max2 = XMVectorSplatZ(vAbs);
XMVECTOR max3 = XMVectorSplatW(vAbs);
max0 = XMVectorMax(max0, max1);
max2 = XMVectorMax(max2, max3);
max0 = XMVectorMax(max0, max2);

// Divide by the maximum absolute component.
XMVECTOR normalized = XMVectorDivide(V, max0);

// Set to zero when the original length is zero.

// (sqrLength, sqrLength, sqrLength, sqrLength)
XMVECTOR t0 = XMVector4Dot(normalized, normalized);

// (length, length, length, length)
XMVECTOR length = XMVectorSqrt(t0);

// Divide by the length to normalize.
normalized = XMVectorDivide(normalized, length);

// Set to zero when the original length is zero or infinity.  In the
// latter case, this is considered to be an unexpected condition.
return normalized;
}

``````

### Platform Requirements

Microsoft Visual Studio 2010 or Microsoft Visual Studio 2012 with the Windows SDK for Windows 8. Supported for Win32 desktop apps, Windows Store apps, and Windows Phone 8 apps.

## Requirements

Target Platform Windows