void Render(HDC hdc, RectI target, int pageNo, float zoom) {
ScopedCritSec scope(&currAccess);
if (currBmp && currPage == pageNo && currSize == target.Size())
currBmp->StretchDIBits(hdc, target);
else if (!thread) {
reqPage = pageNo;
reqZoom = zoom;
reqSize = target.Size();
reqAbort = false;
thread = CreateThread(NULL, 0, RenderThread, this, 0, 0);
}
else if (reqPage != pageNo || reqSize != target.Size()) {
if (abortCookie)
abortCookie->Abort();
reqAbort = true;
}
}
void Abort() {
ScopedCritSec scope(&cookieAccess);
if (cookie)
cookie->Abort();
Clear();
}