C++里面的PaintStructure是个什么东西？

是一个绘图结构，这是MSDN上的解释，全是英文的，不知你能不能看懂。我都是开着“金山词霸”的鼠标取词功能读MSDN的，效果非常好：
PAINTSTRUCT
This structure contains information that an application uses to paint the client area of a window owned by that application.

typedef struct tagPAINTSTRUCT {
HDC hdc;
BOOL fErase;
RECT rcPaint;
BOOL fRestore;
BOOL fIncUpdate;
BYTE rgbReserved[32];
} PAINTSTRUCT;
Members
hdc
Handle to the display DC to be used for painting.
fErase
Boolean that specifies whether the background must be erased. This value is nonzero if the application should erase the background. The application is responsible for erasing the background if a window class is created without a background brush. For more information about backgrounds, see the description of the hbrBackground member of the WNDCLASS structure.
rcPaint
Specifies a RECT structure that specifies the upper left and lower right corners of the rectangle in which the pa