ExternalProject_Add allows build and install libraries.
I experiment with it and as an example I use Slicer 3D. I can see that Slicer builds some libs and other libs Slicer builds-install.
What is the logic behind that? When usually developpers use ExternalProject_Add to simply build and when to build-install libraries?
As for me I’m trying understand do I need to build or build-install Eigen3 (header only) via ExternalProject_Add?
I don’t know what makes DCMTK so different. I suspect that might be because it uses a shared install directory somewhere, but I think Slicer developers are better positioned to answer.