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XMFLOAT3PK structure (directxpackedvector.h)

  • Article

Describes a 3D vector with X and Y components stored as 11 bit floating point number, and Z component stored as a 10 bit floating-point value.

For a list of additional functionality, such as constructors and operators, available using XMFLOAT3PK when programming in C++, see XMFLOAT3PK Extensions.

Syntax

struct XMFLOAT3PK {
  union {
    struct {
      uint32_t xm : 6;
      uint32_t xe : 5;
      uint32_t ym : 6;
      uint32_t ye : 5;
      uint32_t zm : 5;
      uint32_t ze : 5;
    };
      uint32_t v;
  };
  void         XMFLOAT3PK();
  void         XMFLOAT3PK(
    const XMFLOAT3PK & unnamedParam1
  );
  XMFLOAT3PK & operator=(
    const XMFLOAT3PK & unnamedParam1
  );
  void         XMFLOAT3PK(
    XMFLOAT3PK && unnamedParam1
  );
  XMFLOAT3PK & operator=(
    XMFLOAT3PK && unnamedParam1
  );
  void         XMFLOAT3PK(
    uint32_t Packed
  ) noexcept;
  void         XMFLOAT3PK(
    float _x,
    float _y,
    float _z
  ) noexcept;
  void         XMFLOAT3PK(
    const float *pArray
  ) noexcept;
  void         operator uint32_t() noexcept;
  XMFLOAT3PK & operator=(
    uint32_t Packed
  ) noexcept;
};

Members

6 xm

The 6-bit mantissa for the x component.

5 xe

The 5-bit biased exponent for the x component.

6 ym

The 6-bit mantissa for the y component.

5 ye

The 5-bit biased exponent for the y component.

5 zm

The 5-bit mantissa for the z component.

5 ze

The 5-bit biased exponent for the z component.

v

Unsigned 32-bit integer representing the 3D vector.

void XMFLOAT3PK()

Default constructor for XMFLOAT3PK.

Default constructor for XMFLOAT3PK.

Note  This constructor is only available under C++.
 

void XMFLOAT3PK( const XMFLOAT3PK & unnamedParam1)

A constructor for XMFLOAT3PK.

A constructor for XMFLOAT3PK.

Note  This constructor is only available under C++.

XMFLOAT3PK & operator=( const XMFLOAT3PK & unnamedParam1)

void XMFLOAT3PK( XMFLOAT3PK && unnamedParam1)

Assigns the vector component data from one instance of XMFLOAT3SE to the current instance of XMFLOAT3SE.

This operator assigns the vector component data from one instance of XMFLOAT3SE to the current instance of XMFLOAT3SE.

Note  This operator is only available under C++.

XMFLOAT3PK & operator=( XMFLOAT3PK && unnamedParam1)

Assigns the vector component data from one instance of XMFLOAT3PK to the current instance of XMFLOAT3PK.

This operator assigns the vector component data from one instance of XMFLOAT3PK to the current instance of XMFLOAT3PK.

Note  This operator is only available under C++.

void XMFLOAT3PK( uint32_t Packed) noexcept

Initializes a new instance of XMFLOAT3PK from a uint32_t variable containing component data in a packed format.

This constructor initializes a new instance of XMFLOAT3PK from a uint32_t variable containing component data in a packed format.

Note  This constructor is only available under C++.
 

void XMFLOAT3PK( float _x, float _y, float _z) noexcept

Initializes a new instance of XMFLOAT3PK from three float arguments.

This constructor initializes a new instance of XMFLOAT3PK from three float arguments.

Note  This constructor is only available under C++.
 

void XMFLOAT3PK( const float *pArray) noexcept

Initializes a new instance of XMFLOAT3PK from a three element float array argument.

This constructor initializes a new instance of XMFLOAT3PK from a three element float array argument.

Note  This constructor is only available under C++.

void operator uint32_t() noexcept

Returns an instance of uint32_t containing the components of the XMFLOAT3PK instance in a packed format.

This operator returns an instance of uint32_t containing the components of the XMFLOAT3PK instance in a packed format.

Note  This operator is only available under C++.
 

XMFLOAT3PK & operator=( uint32_t Packed) noexcept

This operator assigns the vector component data packed in an instance of uint32_t to the current instance of XMFLOAT3PK.

Note  This operator is only available under C++.
 

Remarks

There are no sign bits. This means all partial-precision numbers are positive. The z component is stored in the most significant bits, and the x component is stored in the least significant bits like this:

(Z10Y11X11): [31] ZZZZZzzz zzYYYYYy yyyyyXXX XXxxxxxx [0]

Or in detail:

  • Bits 0-5 of v are the 6 bit mantissa of the x component's floating point value: the xm member of the structure.
  • Bits 6-10 of v are the 5 bit exponent of the x component's floating point value the xe member of the structure.
  • Bits 11-16 of v are the 6-bit mantissa of the y component's floating point value: the ym member of the structure.
  • Bits 17-21 of v are the 5 bit exponent of the y component's floating point value: the ye member of the structure.
  • Bits 22-26 of v are the 5 bit mantissa of the z component's floating point value: the zm member of the structure.
  • Bits 27-31 of v are the 5 bit exponent of the z component's floating point value: the ze member of the structure.
XMFLOAT3PK can be loaded into instances of XMVECTOR by using XMLoadFloat3PK.

Instances of XMVECTOR can be stored into an instance of XMFLOAT3PK with XMStoreFloat3PK.

MIN_F10 / MIN_F11 = 6.10352e-5

MAX_F10 = 64512

MAX_F11 = 65024

Namespace: Use DirectX::PackedVector

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
Header directxpackedvector.h

See also

DirectXMath Library Structures

XMFLOAT3PK Extensions