【请教】图形问题！

Question

如题：
1、有两张图片，一张是红色的点，一张是蓝色的点，两张图片叠加在一起，红色点和蓝色点相交部分变为黑色，怎样在DELPHI中实现？
2、假如有一张图，图中是个黑色的箭头，背景是白色的，用程序产生离子，如何确定离子投影出来的是箭头的图形？如何在delphi中实现？
如图：
http://www.bababian.com/photos/20060215/D2AF3B6E3A5282ABE532AD6403480A6F_500.jpghttp://www.bababian.com/photos/20060124/015F00D558B4D197E0E4FE2DE669BFE2_500.jpg请大家帮帮小弟，先多谢了！

Answer 1

//第一个问题参考如下代码
procedure TForm1.Button1Click(Sender: TObject);
begin
  Canvas.CopyMode := cmSrcCopy;
  Canvas.CopyRect(
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height),
    Image1.Picture.Bitmap.Canvas,
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height)
  );  Canvas.CopyMode := cmSrcAnd;
  Canvas.CopyRect(
    Rect(0, 0, Image2.Picture.Bitmap.Width, Image2.Picture.Bitmap.Height),
    Image2.Picture.Bitmap.Canvas,
    Rect(0, 0, Image2.Picture.Bitmap.Width, Image2.Picture.Bitmap.Height)
  );
end;//第二个问题没看明白,两张图片看不出有什么区别,目标效果图是什么样的?

Answer 2

//第二个问题参考如下代码procedure TForm1.Button1Click(Sender: TObject);
begin
  Image3.Picture.Bitmap.Width := Image1.Picture.Bitmap.Width;
  Image3.Picture.Bitmap.Height := Image1.Picture.Bitmap.Height;
  Image3.Canvas.FillRect(Image3.Canvas.ClipRect);  Image3.Canvas.CopyMode := cmSrcCopy;
  Image3.Canvas.CopyRect(
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height),
    Image1.Picture.Bitmap.Canvas,
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height)
  );  Image3.Canvas.CopyMode := cmNotSrcErase;
  Image3.Canvas.CopyRect(
    Rect(0, 0, Image2.Picture.Bitmap.Width, Image2.Picture.Bitmap.Height),
    Image2.Picture.Bitmap.Canvas,
    Rect(0, 0, Image2.Picture.Bitmap.Width, Image2.Picture.Bitmap.Height)
  );  Image4.Picture.Bitmap.Width := Image1.Picture.Bitmap.Width;
  Image4.Picture.Bitmap.Height := Image1.Picture.Bitmap.Height;
  Image4.Canvas.FillRect(Image3.Canvas.ClipRect);  Image4.Canvas.Brush.Color := $000FFF;
  Image4.Canvas.FillRect(Canvas.ClipRect);
  Image4.Canvas.CopyMode := cmSrcErase;
  Image4.Canvas.CopyRect(
    Rect(0, 0, Image3.Picture.Bitmap.Width, Image3.Picture.Bitmap.Height),
    Image3.Picture.Bitmap.Canvas,
    Rect(0, 0, Image3.Picture.Bitmap.Width, Image3.Picture.Bitmap.Height)
  );  Canvas.CopyMode := cmSrcCopy;
  Canvas.CopyRect(
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height),
    Image1.Picture.Bitmap.Canvas,
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height)
  );  Canvas.CopyMode := cmNotSrcErase;
  Canvas.CopyRect(
    Rect(-1, -1, Image1.Picture.Bitmap.Width - 1, Image1.Picture.Bitmap.Height - 1),
    Image4.Picture.Bitmap.Canvas,
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height)
  );  Canvas.CopyMode := cmNotSrcErase;
  Canvas.CopyRect(
    Rect(+1, +1, Image1.Picture.Bitmap.Width + 1, Image1.Picture.Bitmap.Height + 1),
    Image4.Picture.Bitmap.Canvas,
    Rect(0, 0, Image1.Picture.Bitmap.Width, Image1.Picture.Bitmap.Height)
  );
end;