Xfce by design leaves out much of the eye candy of other systems. There aren't even fancy animations. The most you can get is 2D accelerated compositing if your driver supports it (most do), unless you are willing to install other software.

You have to enable the compositing feature in XFCE's settings manager, and to my memory it will use hardware acceleration automatically. (You may need to do this manually but I am on unity so I cannot test it).