CairoExplorer.FileToIconConverter.resizeImage C# (CSharp) Метод

        private static Bitmap resizeImage(Bitmap imgToResize, System.Drawing.Size size, int spacing)
        {
            int sourceWidth = imgToResize.Width;
            int sourceHeight = imgToResize.Height;

            float nPercent = 0;
            float nPercentW = 0;
            float nPercentH = 0;

            nPercentW = ((float)size.Width / (float)sourceWidth);
            nPercentH = ((float)size.Height / (float)sourceHeight);

            if (nPercentH < nPercentW)
                nPercent = nPercentH;
            else
                nPercent = nPercentW;

            int destWidth = (int)((sourceWidth * nPercent) - spacing * 4);
            int destHeight = (int)((sourceHeight * nPercent) - spacing * 4);

            int leftOffset = (int)((size.Width - destWidth) / 2);
            int topOffset = (int)((size.Height - destHeight) / 2);


            Bitmap b = new Bitmap(size.Width, size.Height);
            Graphics g = Graphics.FromImage((Image)b);
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
            g.DrawLines(System.Drawing.Pens.Silver, new PointF[] {
                new PointF(leftOffset - spacing, topOffset + destHeight + spacing), //BottomLeft
                new PointF(leftOffset - spacing, topOffset -spacing),                 //TopLeft
                new PointF(leftOffset + destWidth + spacing, topOffset - spacing)});//TopRight

            g.DrawLines(System.Drawing.Pens.Gray, new PointF[] {
                new PointF(leftOffset + destWidth + spacing, topOffset - spacing),  //TopRight
                new PointF(leftOffset + destWidth + spacing, topOffset + destHeight + spacing), //BottomRight
                new PointF(leftOffset - spacing, topOffset + destHeight + spacing),}); //BottomLeft

            g.DrawImage(imgToResize, leftOffset, topOffset, destWidth, destHeight);
            g.Dispose();

            return b;
        }