_Dot3dVW0

Computes the inner product of a pair of three or four-dimensional vectors with the "w" coordinate forced to 0.

float _Dot3dVW0( 
  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 a source vector will always force to 0.

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

The following example shows how to use Dot3dVW0 to compute the inner products of three or four dimensional vectors.

/***********************************************************/
#include <stdio.h>
#include <shintr.h>
void main()
{
     float result;
     float v1[4]={1.0,2.0,3.0,4.0};
     float v2[4]={2.0,3.0,4.0,5.0};
     result = _Dot3dVW0(v1,v2);
/***********************************************************/
     printf("result=%f\n", result);
}

This example results in the following output.

retval=20.000000

Requirements

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

See Also

_Dot4dV | _Dot3dVW1 | Microprocessor-specific Intrinsic Functions

 Last updated on Thursday, April 08, 2004

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