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XMXDECN4::XMXDECN4(constfloat*) function (directxpackedvector.h)

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Initializes a new instance of XMXDECN4 from a four element float array argument.

This constructor initializes a new instance of XMXDECN4 from a four element float array argument.

Note  This constructor is only available under C++.

Syntax

void XMXDECN4(
  const float *pArray
) noexcept;

Parameters

pArray

Four element floating point array containing the values used to initialize the four components of a new instance of XMXDECN4.

Return value

None

Remarks

Array elements are mapped to the vector components of a new instance of XMXDECN4 as follows:

Vector Component Array Element Range Description
x pArray[0] -0.0, 1.0 During instantiation, pArray[0] is clamped between -1 and 1, multiplied by 511.0f and assigned to x.
y pArray[1] -0.0, 1.0 During instantiation, pArray[1] is clamped between -1 and 1, multiplied by 511.0f, and then assigned to y.
z pArray[2] -0.0, 1.0 During instantiation, pArray[2] is clamped between -1 and 1, multiplied by 511.0f, and then assigned to z.
w pArray[3] 0.0, 1.0 During instantiation, pArray[3] is clamped between 0 and 1, and then assigned to w. This argument should be between 0.0 and 1.0; during the instantiation of an instance of XMXDECN4, it is multiplied by 3.0f and then stored as the w member of the structure. 
XMXDECN4 instance;
_x1=min( max( pArray[0], -1.0 ), 1.0 );
_y1=min( max( pArray[1], -1.0 ), 1.0 );
_z1=min( max( pArray[2], -1.0 ), 1.0 );
_w1=min( max( pArray[3], 0.0 ), 1.0 );
_x1 = round( _x1 *  511.0f);
_y1 = round( _y1 *  511.0f);
_z1 = round( _z1 *  511.0f);
_w1 = round( _w1 *  3.0f);

instance.v =  ( (uint32_t)_w1 << 30) |
                (((uint32_t)_z1 & 0x3FF) << 20) |
                (((uint32_t)_y1 & 0x3FF) << 10) |
                (((uint32_t)_x1 & 0x3FF));

Requirements

Requirement Value
Target Platform Windows
Header directxpackedvector.h

See also

Reference

XMXDECN4

XMXDECN4 Constructors