//
// Returns a vector that is orthogonal to A (but of arbitrary length).
//
Vector OrthogonalTo( const Vector &A )
{
Vector B( A.Size() );
double c = 0.5 * SupNorm( A );
if( A.Size() < 2 )
{
// Just return the zero-vector.
}
else if( c == 0.0 )
{
B(0) = 1.0;
}
else for( register int i = 0; i < A.Size(); i++ )
{
if( Abs( A(i)) > c )
{
int k = ( i > 0 ) ? i - 1 : i + 1;
B(k) = -A(i);
B(i) = A(k);
break;
}
}
return B;
}
/*-------------------------------------------------------------------------*
* O R T H O G O N A L T O *
* *
* Returns a vector that is orthogonal to A (but of arbitrary length). *
* *
*-------------------------------------------------------------------------*/
Vec3 OrthogonalTo( const Vec3 &A )
{
float c = 0.5 * SupNorm( A );
if( c == 0.0 ) return Vec3( 1.0, 0.0, 0.0 );
if( c <= Abs(A.X()) ) return Vec3( -A.Y(), A.X(), 0.0 );
if( c <= Abs(A.Y()) ) return Vec3( 0.0, -A.Z(), A.Y() );
return Vec3( A.Z(), 0.0, -A.X() );
}
