_beginPaint _impl beginPaint beginPaintBuffered beginPath bezierTo clearCachedBitmap clearRect clearWindow clipPath clipRect closePath drawBitmap drawCachedBitmap drawCachedBitmap2 drawEllipse drawHandle drawLine drawPath drawRect drawTextAt endPaint getEncoder GiGdipCanvas hasCachedBitmap isBufferedDrawing lineTo moveTo quadTo restoreClip save saveCachedBitmap saveClip setBrush setPen thumbnailImage ~GiGdipCanvas

drawCachedBitmap() bool GiGdipCanvas::drawCachedBitmap ( int  x = 0, int  y = 0, bool  secondBmp = false  ) 显示上次缓存的内容