XMVectorReciprocalSqrtEst function (directxmath.h)
Estimates the per-component reciprocal square root of a vector.
Syntax
XMVECTOR XM_CALLCONV XMVectorReciprocalSqrtEst(
[in] FXMVECTOR V
) noexcept;
Parameters
[in] V
Vector whose reciprocal square root is estimated.
Return value
Returns a vector. Each component is an estimate of the reciprocal square-root of the corresponding component of V.
Remarks
The reciprocal square-root operation handles special input values as follows.
| Input Value | Return Value |
|---|---|
| +Infinity | 0 |
| +0.0f | +Infinity |
| -0.0f | -Infinity |
| < 0.0f | QNaN |
Est functions offer increased performance at the expense of reduced accuracy.
Est functions are appropriate for non-critical calculations where accuracy can be sacrificed for speed.
The exact amount of lost accuracy and speed increase are platform dependent.
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
| Requirement | Value |
|---|---|
| Target Platform | Windows |
| Header | directxmath.h (include DirectXMath.h) |