[CMake] Add resource file (.r) to Xcode project

[Kevin Molcard]

Hi all,
I am pretty new to CMake and I am trying to port an AudioUnit project.
Therefore, I have to compile a resource file (.r) with the Rez compiler.
Is it possible to do that with Cmake?

So far the only way to do that is to manually call the Rez compiler 
through add_custom_command.

Thanks in advance,
Kevin