/// <summary>
        /// Generates a toroidally tiled noise
        /// </summary>
        private static unsafe void GenerateNoise( Texture3dData data, Noise3dTextureBuilderParameters parameters, byte* voxels )
        {
            SimpleNoise3d sNoise = new SimpleNoise3d();
            Noise noise = new Noise( );
            float nW	= parameters.NoiseWidth;
            float nH	= parameters.NoiseHeight;
            float nD	= parameters.NoiseDepth;
            float nX0	= parameters.NoiseX;
            float nY0	= parameters.NoiseY;
            float nZ0	= parameters.NoiseZ;
            float nXInc = nW / data.Width;
            float nYInc = nH / data.Height;
            float nZInc = nD / data.Depth;
            byte* voxel = voxels;
            int bytesPerVoxel = TextureFormatInfo.GetSizeInBytes( parameters.Format );
            if ( bytesPerVoxel != 3 && bytesPerVoxel != 4 )
            {

                throw new InvalidDataException( string.Format( "Unexpected voxel stride of {0} - expected either 3 or 4 from format {1}", bytesPerVoxel, parameters.Format ) );
            }

            //	Check hacked channel expectations...
            bool hasAlpha = TextureFormatInfo.HasAlphaChannel( parameters.Format );
            float nZ = nZ0;
            float maxNoise = float.MinValue;
            float minNoise = float.MaxValue;
            for ( int z = 0; z < parameters.Depth; ++z, nZ += nZInc )
            {
                float nY = nY0;
                for ( int y = 0; y < parameters.Height; ++y, nY += nYInc )
                {
                    float nX = nX0;
                    for ( int x = 0; x < parameters.Width; ++x, nX += nXInc )
                    {
                        switch ( parameters.GenerationType )
                        {
                            case NoiseGenerationType.Grayscale :
                                {
                                    float n = ( 1.0f + sNoise.GetTilingNoise( nX, nY, nZ, nW, nH, nD ) ) / 2;

                                    maxNoise = Math.Max( maxNoise, n );
                                    minNoise = Math.Min( minNoise, n );

                                //	float n = 0.5f + noise.GetNoise( nX, nY, nZ );
                                    voxel[ 0 ] = NoiseToByte( n );
                                    voxel[ 1 ] = voxel[ 0 ];
                                    voxel[ 2 ] = voxel[ 0 ];
                                    if ( hasAlpha )
                                    {
                                        voxel[ 3 ] = voxel[ 0 ];
                                    }
                                    break;
                                }
                            case NoiseGenerationType.MultiChannel :
                                {
                                    float r = noise.GetNoise( nX, nY, nZ );
                                    float g = noise.GetNoise( nX + nW, nY, nZ );
                                    float b = noise.GetNoise( nX, nY + nH, nZ );
                                    voxel[ 0 ] = NoiseToByte( r );
                                    voxel[ 1 ] = NoiseToByte( g );
                                    voxel[ 2 ] = NoiseToByte( b );
                                    if ( hasAlpha )
                                    {
                                        float a = noise.GetNoise( nX, nY, nZ + parameters.NoiseDepth );
                                        voxel[ 3 ] = NoiseToByte( a );
                                    }
                                    break;
                                }
                            case NoiseGenerationType.TilingGrayscale :
                                {
                                    float n = GetTiledNoise( noise, nX, nY, nZ, nX0, nY0, nZ0, nW, nH, nD );
                                    voxel[ 0 ] = NoiseToByte( n );
                                    voxel[ 1 ] = voxel[ 0 ];
                                    voxel[ 2 ] = voxel[ 0 ];
                                    if ( hasAlpha )
                                    {
                                        voxel[ 3 ] = voxel[ 0 ];
                                    }
                                    break;
                                }
                            case NoiseGenerationType.TilingMultiChannel :
                                {
                                    float r = GetTiledNoise( noise, nX, nY, nZ, nX0, nY0, nZ0, nW, nH, nD );
                                    float g = GetTiledNoise( noise, nX + nW, nY, nZ, nX0 + nW, nY0, nZ0, nW, nH, nD );
                                    float b = GetTiledNoise( noise, nX, nY + nH, nZ, nX0, nY0 + nH, nZ0, nW, nH, nD );
                                    voxel[ 0 ] = NoiseToByte( r );
                                    voxel[ 1 ] = NoiseToByte( g );
                                    voxel[ 2 ] = NoiseToByte( b );
                                    if ( hasAlpha )
                                    {
                                        float a = GetTiledNoise( noise, nX, nY, nZ + nD, nX0, nY0, nZ0 + nD, nW, nH, nD );
                                        voxel[ 3 ] = NoiseToByte( a );
                                    }
                                    break;
                                }
                            case NoiseGenerationType.BigNoise :
                                {
                                    float real = 0.5f + GetTiledNoise( noise, nX, nY, nZ, nX0, nY0, nZ0, nW, nH, nD );
                                    float imag = 0.5f + GetTiledNoise( noise, nX + nW, nY + nH, nZ + nD, nX0, nY0, nZ0, nW, nH, nD );

                                //	maxNoise = Math.Max( maxNoise, real );
                                //	minNoise = Math.Min( minNoise, real );

                                    double a = Math.PI + Math.PI * real;

                                    voxel[ 0 ] = NoiseToByte( real );
                                    voxel[ 1 ] = NoiseToByte( imag );
                                    voxel[ 2 ] = ( byte )Utils.Clamp( ( Math.Sin( a ) + 1 ) * 127.5, 0, 255 );
                                    voxel[ 3 ] = ( byte )Utils.Clamp( ( Math.Cos( a ) + 1 ) * 127.5, 0, 255 );

                                    break;
                                }
                            default :
                                throw new NotSupportedException( string.Format( "Noise generation type \"{0}\" is not supported yet", parameters.GenerationType ) );
                        }

                        voxel += bytesPerVoxel;
                    }
                }
            }
        }
 private static float GetNoise( Noise noise, float w, float h, float d, float x, float y, float z )
 {
     return noise.GetNoise( x % w, y % h, z % d );
 }