CMake installation directory

Dear authors, I have a question or feature request about CMake install directory - I would like to install the RooUnfold library and include files to a specific directory - I tried what I use in other packages

cmake -DCMAKE_INSTALL_PREFIX:PATH=... ../RooUnfold/

but make install doesn't seem to use the CMAKE_INSTALL_PREFIX variable. Am I doing something wrong?

I unfortunately don't have much experience with CMake, I can see that the variable is still present in build/cmake_install.cmake but then it seems to be ignored

Thank you, Zdenek