c# WinForm制作图片编辑工具(图像拖动、缩放、旋转、抠图)

public class ImageProperty
 {
 public string Name { get; set; }
 public Image EditImage { get; set; } //原始图片

 public int ActualWidth => EditImage.Width; //实际尺寸
 public int ActualHeight => EditImage.Height;

 public bool ShowImageTip { get; set; } = true;

 public bool LockSizeRate { get; set; } //比例是否锁定
 public Size DrawSize { get; set; } //显示尺寸
 public object Tag { get; set; }
 }

 public class ImageEditInfo
 {
 public ImageProperty ImageProperty { get; set; }

 public Point Location { get; set; } = new Point(0, 0); //相对于打印区的位置
 public Point LocationTopRight => new Point(Location.X + Width, Location.Y);
 public Point LocationBottomRight => new Point(Location.X + Width, Location.Y + Height);
 public Point LocationBottomLeft => new Point(Location.X, Location.Y + Height);

 public int RightX => Location.X + Width;
 public int ButtomY => Location.Y + Height;

 public Size DrawSize
 {
 get { return ImageProperty.DrawSize; }
 set { ImageProperty.DrawSize = value; }
 }

 public Image Image => ImageProperty.EditImage;

 public float RotateAngle { get; set; } = 0; //旋转角度

 public bool IsSelect { get; set; }

 public bool LockSizeRate //显示比例是否锁定
 {
 get
 {
 return ImageProperty.LockSizeRate;
 }
 set
 {
 ImageProperty.LockSizeRate = value;
 }
 }

 public int Width
 {
 get
 {
 return DrawSize.Width;
 }
 set
 {
 ImageProperty.DrawSize = new Size(value, DrawSize.Height);
 }
 }

 public int Height
 {
 get
 {
 return DrawSize.Height;
 }
 set
 {
 ImageProperty.DrawSize = new Size(DrawSize.Width, value);
 }
 }

 public bool ShowImageTip
 {
 get { return ImageProperty.ShowImageTip; }
 set { ImageProperty.ShowImageTip = value; }
 } 

 public Point? RotatioBasePoint { get; set; } //旋转基点

 public Point RotatioBasePointValue => RotatioBasePoint.Value;

 public bool HasRotatioBasePoint => (RotatioBasePoint != null && RotatioBasePoint.HasValue);
}

/// <summary>
 /// pointMove相对于removeAt，以一定角度旋转
 /// </summary>
 /// <param name="pointMove"></param>
 /// <param name="removeAt"></param>
 /// <param name="rotateAngle"></param>
 /// <param name="clockwise"></param>
 /// <returns></returns>
 public static Point RotationAt(Point pointMove, Point removeAt, double rotateAngle, bool clockwise)
 {
 if (rotateAngle == 0)
 return pointMove;

 lock (matrix)
 {
 matrix.Reset();
 matrix.Rotate((float)(clockwise ? rotateAngle : -rotateAngle));

 Point pt2 = new Point(pointMove.X - removeAt.X, pointMove.Y - removeAt.Y);
 Point[] pts = new Point[] { new Point(pt2.X, pt2.Y) };
 matrix.TransformPoints(pts);

 Point result = new Point(pts[0].X + removeAt.X, pts[0].Y + removeAt.Y);
 return result;
 }
 }

 internal EN_LinePart MouseMove_HitTest(Point pt)
 {
 //鼠标位置 反向旋转，
 pt = DrawHelper.RotationAt(pt, Location, RotateAngle, false);

 //下面就是 和正常判断逻辑一样
 EN_LinePart result = MouseMove_HitTest_Corner(pt);
 if (result != EN_LinePart.无)
 return result;
}

void DrawWithRotation(Graphics g, bool saveToFile)
 {
 //设置质量
 ImageHelper.SetHighQuality(g);

 //置背景色
 if (!saveToFile)
 g.Clear(BackgroundColor);

 ImageEditInfo selectImage = null;
 foreach (ImageEditInfo imageInfo in ImageGroup.ListImageToDraw)
 {
 //画图片
 if (imageInfo.IsSelect)
 {
  Debug.Assert(selectImage == null);
  selectImage = imageInfo;
 }

 g.TranslateTransform(imageInfo.Location.X, imageInfo.Location.Y);
 g.RotateTransform(imageInfo.RotateAngle);

 //是否需要画 抠图
 Image imageToDraw = imageInfo.Image;
 if (imageInfo.CutStat == ImageCutStat.have_cut
  && imageInfo.CutPoints.Count > 2)
 {
  Bitmap bitmap = imageToDraw as Bitmap;
  System.Windows.Point[] points = imageInfo.CutPoints.Select(o => new System.Windows.Point(o.X,o.Y)).ToArray();
  Bitmap cutBitmap = ImageCutout.GetImage(bitmap, points);
  imageToDraw = cutBitmap;
 }

 g.DrawImage(imageToDraw,
  new Rectangle(0, 0, imageInfo.DrawSize.Width, imageInfo.DrawSize.Height),
  new Rectangle(0, 0, imageInfo.Image.Width, imageInfo.Image.Height),
  GraphicsUnit.Pixel);

 //画旋转基点
 if (!saveToFile && imageInfo.HasRotatioBasePoint)
 {
  Point pt = imageInfo.RotatioBasePointValue;
  g.FillEllipse(RotatioBaseBrush, pt.X - RotatioBaseRadius, pt.Y - RotatioBaseRadius, RotatioBaseRadius * 2, RotatioBaseRadius * 2);
 }

 //显示信息
 if (!saveToFile && imageInfo.ShowImageTip)
 { 
  ImageProperty ImageProperty = imageInfo.ImageProperty;
  string info = string.Format($"({imageInfo.Location.X},{imageInfo.Location.Y}) ({ImageProperty.ActualWidth}X{ImageProperty.ActualHeight}--{imageInfo.DrawSize.Width}X{imageInfo.DrawSize.Height}) (∠{imageInfo.RotateAngle.ToString("0.00")})");

  SizeF sizeF = g.MeasureString(info, _drawProperty.TxtFont);
  g.FillRectangle(_drawProperty.TxtBackgroundBrush,
  new RectangleF(new Point(), sizeF));

  g.DrawString(info, _drawProperty.TxtFont, _drawProperty.TxtBrush, new Point());
 }

 //画抠图线
 if(!saveToFile
  && imageInfo.CutStat == ImageCutStat.in_cuting
  && imageInfo.CutPoints.Count>1)
 {
  for(int i=1;i< imageInfo.CutPoints.Count;i++ )
  {
  g.DrawLine(SelectBorderPen, imageInfo.ToDestImage(imageInfo.CutPoints[i-1]),
  imageInfo.ToDestImage(imageInfo.CutPoints[i]));
  }

  if(imageInfo.CutPoints.Count > 2)
  {
  g.DrawLine(SelectBorderPen, imageInfo.ToDestImage(imageInfo.CutPoints.First()),
  imageInfo.ToDestImage(imageInfo.CutPoints.Last()));
  }
 }

 g.ResetTransform();
 }

 //画选中状态 
 if (!saveToFile && selectImage != null)
 {
 DrawSelectImageWithRotation(g, selectImage);
 }
 }