关于IImage.Draw的速度

hanzhenwei

关于IImage.Draw的速度 [复制链接]

在PPC2005上调用Imaging API
IImagingFactory *fac = .........(创建com)
IImage *image;
fac.CreateImageFromFile ("filename", &image)
image->Draw (hdc, &dstRect, NULL);
结果一张480*160的png图片居然用了140多tickcount来draw.
(同时调用多次draw,每次都要100毫秒)

有什么好的解决方法阿

unsettled

   现在内存中创建DC，draw到内存DC，然后bitblt到目标DC，不仅速度快，还可以实现很多效果。我的数码相框就是这样做的
HDC m_hdc = GetDc(NULL);
HDC hMenDc = CreateCompatibleDC(NULL);
HBITMAP hBmp = CreateCompatibleBitmap(hMenDc,800,600);
HGDIOBJ hOldBmp = SelectObject(hMenDc,hbmp);
RECT rc;
rc.left = 0;
rc.top = 0;
rc.bottom = 800;
rc.right = 600;
pImage->Draw(m_hdc,&rc,NULL);
BitBlt(m_hdc,rc.left,rc.top,800,600,hMenDc,0,0,SRCCOPY);
SAFERELEASE(pImage)
SelectObject(hMenDc,hOldBmp );
DeleteObject(hBmp );
DeleteDC(hMenDc);

以上是代码，至于效果，就不发了