Megawizard TCL script interface

I would like to automate the process of generating custom megafunctions.

I was under the impression that then entirety of Quartus II could be automated using TCL scripts, but I cannot seem to locate any functions that can generate custom megafunctions for you. Does this have to be done via the GUI?

The reason I ask is because I am using SOPC builder to build a system that has some custom components within it. This means I am using my own custom _hw.tcl files to describe the interfaces on my custom HDL components.

I would also like to be able to generate parameterized megafunctions based on the parameters passed to the instances of the custom components in SOPC builder, without having to generate all of these megafunctions by hand using the Megawizard GUI. Is what I want to do possible?

Thanks!