圆形截图

1.算法

 

/// <summary>
        /// 圆形截图
        /// </summary>
        /// <param name="rec">截取部分矩形的值：rec(X，Y, Width，Height)</param>
        /// <param name="size">画布大小size(宽，高)</param>
        /// <returns></returns>
        public static BitmapImage CutEllipse(Rectangle rec, System.Drawing.Size size)
        {
            Bitmap bitmap = new Bitmap(size.Width, size.Height);
            Image img = bitmapFill;
            using (Graphics g = Graphics.FromImage(bitmap))
            {
                using (TextureBrush br = new TextureBrush(img, System.Drawing.Drawing2D.WrapMode.Clamp, rec))
                {
                    br.ScaleTransform(bitmap.Width / (float)rec.Width, bitmap.Height / (float)rec.Height);
                    g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;//消除锯齿
                    g.FillEllipse(br, new Rectangle(System.Drawing.Point.Empty, size));
                }
            }return GetBitmapImageBybitmap(bitmap);
        }

2.调用

//System.Drawing.Rectangle(左上角X坐标, 左上角Y坐标, 宽, 高)
//System.Drawing.Size(画布的宽, 画布的高)
this.ShotImage.Source = ImageHelper.CutEllipse(new System.Drawing.Rectangle(RouStaX, RouStaY, width, height), new System.Drawing.Size(width, height));