双缓冲的aero玻璃效果下的文字输出，是用BufferPaint（vista/win7独有的api实现的）是无闪烁的，也不需要用gdiplus先把文字栅格化到位图上。-Double buffer text render out with aero, use buffer paint api, no gdi plus, no blink.

A small sample showing how to create a non-rectangular window. Windows provides an API called SetWindowRgn() that makes it easy for applications to create irregularly shaped windows. Then you need to catch the WM_NCHITTEST, WM_NCACTIVATE and WM_NCP