BRDFSlices.DisplayForm.BuildScaleTable C# (CSharp) Method

        protected void BuildScaleTable()
        {
            m_Intersections = new double[INTERSECTIONS_TABLE_SIZE,INTERSECTIONS_TABLE_SIZE];

            // Use Newton Raphson method to compute the interesection
            //  for the equation f(x) = tan(a.x).tan(x) - b = 0
            //
            // The derivative of f(x) is:
            //	f'(x) = a.tan(x)/cos²(a.x) + tan(a.x)/cos²(x)
            //
            int	SumIterations = 0;
            for ( int Y=0; Y < INTERSECTIONS_TABLE_SIZE; Y++ )
            {
                double	PhiD = Y * 0.5 * Math.PI / (INTERSECTIONS_TABLE_SIZE-1);
                double	b = 1.0 / Math.Cos( PhiD );

                for ( int X=0; X < INTERSECTIONS_TABLE_SIZE; X++ )
                {
                    double	SlopeAngle = X * 0.5 * Math.PI / (INTERSECTIONS_TABLE_SIZE-1);
                    double	a = Math.Tan( SlopeAngle );

                    int		IterationsCount;
                    double	Intersection = SolveNewton( a, b, out IterationsCount );
                    m_Intersections[X,Y] = (float) Intersection;

                    SumIterations += IterationsCount;
                }
            }
            double	AverageIterationsCount = (double) SumIterations / (INTERSECTIONS_TABLE_SIZE*INTERSECTIONS_TABLE_SIZE);	// Get average iterations per texel

            // Save the result
            using ( FileStream S = new FileInfo( "Intersections" + INTERSECTIONS_TABLE_SIZE + "x" + INTERSECTIONS_TABLE_SIZE + ".double" ).Create() )
                using ( BinaryWriter Writer = new BinaryWriter( S ) )
                {
                    for ( int Y=0; Y < INTERSECTIONS_TABLE_SIZE; Y++ )
                        for ( int X=0; X < INTERSECTIONS_TABLE_SIZE; X++ )
                            Writer.Write( m_Intersections[X,Y] );
                }

            using ( FileStream S = new FileInfo( "Intersections" + INTERSECTIONS_TABLE_SIZE + "x" + INTERSECTIONS_TABLE_SIZE + ".float" ).Create() )
                using ( BinaryWriter Writer = new BinaryWriter( S ) )
                {
                    for ( int Y=0; Y < INTERSECTIONS_TABLE_SIZE; Y++ )
                        for ( int X=0; X < INTERSECTIONS_TABLE_SIZE; X++ )
                            Writer.Write( 1.0f / (float) m_Intersections[X,Y] );
                }
        }