为什么使用DrawText API绘制时字体边缘不平滑

当我在dc上绘制文本时，文本会出现粗糙的边缘，而在这个WindowProc处理的多个窗口上，每个窗口之间的文本看起来都不一样，这看起来很不专业。有没有一种方法可以把它画出来，使它的边缘清晰、光滑？

    case WM_PAINT:
    {
    GetClientRect(hwnd, &rect);
    hdc = BeginPaint(hwnd, &ps);
    hdcmem = CreateCompatibleDC(hdc);
    BITMAP bm;      
    HBITMAP hbmold =  (HBITMAP)SelectObject(hdcmem, gbutton);
    GetObject(gbutton, sizeof(bm), &bm);
    SetBkMode(hdcmem, TRANSPARENT);
    SetTextColor(hdcmem, RGB(74,88,91));
    HFONT hf = CreateFont(30, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, L"Myriad Pro");
    HFONT hfold = (HFONT)SelectObject(hdcmem, hf);
    //the next line works fine, but with rough text edges.
    DrawText(hdcmem, L"Drag arnFilernHere", -1, &rect, DT_CENTER | DT_VCENTER  );
    SelectObject(hdcmem, hfold);
    BitBlt(hdc, 0,0,bm.bmWidth,bm.bmHeight,hdcmem,0,0,SRCCOPY);
    SelectObject(hdcmem, hbmold);
    DeleteDC(hdcmem);
    EndPaint(hwnd, &ps);
    break;
    }