汉字在画布上移动如何清除尾迹？(100分)

请问各位专家汉字在画布上移动如何清除尾迹？

一是完全重画
或是画之前保存要画的区域
移动后恢复
如此如此：）

每次画图时清除背景，或者用底色在原位置上画一次
然后在新位置重画

可以先将背景保存为一幅位图，如果想要擦除，只需要以背景色重画位图区域就行了。
异或方式对字不起作用, 只对直线等起作用

DoubleBuffered := True;


When DoubleBuffered is false, the windowed control paints itself directly to the window. When DoubleBuffered is true, the windowed control paints itself to an in-memory bitmap that is then used to paint the window. Double buffering reduces the amount of flicker when the control repaints, but is more memory intensive.

When a windowed control is a dock site and has an associated dock manager, it must be double-buffered.

Note: Some controls, such as TRichEdit, can抰 paint themselves into a bitmap. For such controls, DoubleBuffered must be set to false.

如果是自己画，DoubleBuffered := True;没有用的。

还是要自己创建一个临时的Bitmap，按htw的方法，先在上面画背景，
再画字，之后再复制到屏幕上。

多人接受答案了。