[CMake] Multiple installer packages from subsets of one large CMake project?

[Kerry Bonin]

Hello! 

We've recently migrated a very large project to CMake, comprised of 
about 15M lines of source spread across about 30 common libraries and 
about 10 applications.  (A VR/MMO/game development platform over P2P and 
associated tools.)  We've brought up the first installer for the main 
application, and have run into an issue that I can't find a clear answer 
to...

Short version:  Is there a simple way to generate multiple separate 
installers from within one CMake project?  

Longer version: We have a source tree structured as shown below.  The 
dependencies are rather complex, so we've always managed the targets 
together (previously in parallel in Developer Studio and make.)  In 
CMake we can now cleanly build any of the targets, and have only one 
build system, which we love!  What we would now like to do is to create 
multiple installer packages that are built from managed subsets of the 
project.  What is the best approach for this?

Thanks!

Kerry Bonin

open source
  libraries
    lib 1
    lib 1 unit tests
    lib 2
    lib 2 unit tests
  applications
    app 1
    app 2
closed source
  libraries
    lib 3
    lib 3 unit tests
    lib 4
    lib 4 unit tests
  applications
    app 3
    app 4