_Dot3dVW1

  • 项目

Computes the inner product of a pair of three or four-dimensional vectors with the "w" coordinate forced to 1.

float _Dot3dVW1( 
  float* vector1, 
  float* vector2 
);

Parameters

  • vector1
    [in] Pointer to a three or four-dimensional source vector.
  • vector2
    [in] Pointer to a three or four-dimensional destination vector.

Return Values

The scalar resulting from the inner product.

Remarks

The fourth coordinate of the source vector will always force to 1.

To implement this function, use the -Qsh4 -Oi flag when compiling.

The following example shows how to compute the inner products of three or four dimensional vectors.

/***********************************************************/
#include <stdio.h>
#include <shintr.h>
void main()
{
     float retval;
     float v1[3] = {1.0, 2.0, 3.0};
     float v2[3] = {2.0, 3.0, 4.0};
     retval = _Dot3dVW1(v1, v2);
/***********************************************************/
     printf("retval=%f\n", retval);
}

This example results in the following output.

retval=21.000000

Requirements

OS Versions: Windows CE .NET 4.0 and later.
Header: shintr.h.

See Also

Microprocessor-specific Intrinsic Functions | _Dot4dV | _Dot3dVW0

 Last updated on Thursday, April 08, 2004

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