Matrix3x3 &Matrix3x3::Inverse( )
{
// Compute determinate
ZED_FLOAT32 Det = Determinate( );
if( ZED::Arithmetic::IsZero( Det ) )
{
zedTrace( "Error: Matrix::Inverse -- singular matrix!" );
return *this;
}
// Set this matrix as the adjoint and multiply by 1/Det to get the
// inverse
ZED_FLOAT32 InverseDet = 1.0f / Det;
*this = Adjoint( );
m_M[ 0 ] *= InverseDet;
m_M[ 1 ] *= InverseDet;
m_M[ 2 ] *= InverseDet;
m_M[ 3 ] *= InverseDet;
m_M[ 4 ] *= InverseDet;
m_M[ 5 ] *= InverseDet;
m_M[ 6 ] *= InverseDet;
m_M[ 7 ] *= InverseDet;
m_M[ 8 ] *= InverseDet;
return *this;
}
bool CMatrix4x4<T>::GetInverseMatrix(CMatrix4x4 &matInverse) const
{
T nDeterminate = Determinate();
int i, j, sign;
if(fabs(nDeterminate) < 0.0005)
{
return false;
}
for(i = 0; i < 4; i++)
{
for(j = 0; j < 4; j++)
{
sign = 1 - ((i+j)%2) * 2;
Matrix3x3<T> matSub = GetSubMatrix3x3(i,j);
T det = matSub.Determinate();
matInverse.m_Entries[i+j*4] = (det * sign)/nDeterminate;
}//end for
}//end for
return true;
}//end GetInverseMatrix
Vector3f Matrix3f::Solve(const Vector3f& constants) const{
float det = Determinate();
float x = SetColumn(0, constants).Determinate() / det;
float y = SetColumn(1, constants).Determinate() / det;
float z = SetColumn(2, constants).Determinate() / det;
return(Vector3f(x, y, z));
}
