Cairo 下载，测试

You need to download the all-in-one bundle available here. You can discover this link yourself by visitinghttp://www.gtk.org/ and clicking "Download", then "Windows (32-bit)". Extract it to a directory that doesn't include spaces, and add that directory to your PATH. You will also need to cabal install gtk2hs-buildtools before you attempt to cabal install gtk.

GTK+ 是多平台制图接口，测试下PDF 转图片处理能力

下载一大堆DLL exe，