If you are already a user, you probably know. If you are looking to find a relatively inexpensive media program that is extremely powerful, you might want to check out this blog post.
http://cdm.link/2016/08/isadora-2-5-creativity-server-makes-using-shaders-easier-ever/
http://cdm.link/2016/08/isadora-2-5-creativity-server-makes-using-shaders-easier-ever/