The easiest is to use an installer, if available for your distribution. However, if you do not have root privileges, you can use a binary package. If you want to build directly from source, you will end up with a binary package adapted for your system. Do not forget to set the Imagine_DIR environment variable.

Installers

If you are using Debian or derivative distribution (Ubuntu...), you can use the appropriate package, which will automatically fetch the dependencies.

64 bits: https://imagine.enpc.fr/~monasse/Imagine++/downloads/Imagine++-6.0.0-Linux-x86_64.deb

To install, enter the following commands in a terminal:

sudo apt install ./Downloads/Imagine++-6.0.0-Linux-x86_64.deb

sudo apt install qtcreator

If the interface complains about "bad package quality" or proposes to "repair", agree and continue installation.

The last point is to set your Imagine_DIR environment variable. To do it permanently: assuming that you installed into /usr/share/Imagine++, as the Debian package does:

enter the following command in a terminal
echo "Imagine_DIR DEFAULT=/usr/share/Imagine++" >> $HOME/.pam_environment
log out and log in again
to check everything works:
cmake -S ${Imagine_DIR}/test -B buildTest

cmake --build buildTest

Go to Usage and check the tests.

Alternative: Binary package

If you use another distribution, or if you do not have root privileges, you can download and extract the binary archive, after having installed the dependencies with your package manager: libqt6opengl6-dev, cmake-qt-gui, g++, gdb.

64 bits: https://imagine.enpc.fr/~monasse/Imagine++/downloads/Imagine++-6.0.0-Linux-x86_64.tar.gz

Alternative: Building from source

If for any reason one of the methods above is not appropriate for you, follow carefully these steps to create a binary package adapted to your system.

1. Sources

Get the sources here https://imagine.enpc.fr/~monasse/Imagine++/downloads/ImaginePP-6.0.0-Source.tar.gz and decompress them.

2. Tools

Get and install the following with your package manager.

Check that Qt is installed. You need not only the Qt runtime libraries, but also the header files. This is in a package called 'libqt6opengl6-dev'.
CMake.
g++.
optionally, doxygen.

The commands below work with Debian and derivatives (Ubuntu and variants):

sudo apt install libqt6opengl6-dev
sudo apt install cmake
sudo apt install g++
sudo apt install doxygen

3. Build

The following commands build the packages.

cmake -DCMAKE_BUILD_TYPE:string=Release -S /path/to/Imagine++-directory -B buildImagine
cmake --build buildImagine
#cmake --build buildImagine -t doc # Remove initial # if doxygen is intalled
cmake --build buildImagine -t package

You should see the binary archive and maybe the Debian package. You should then install one of them, following the instructions above (Installers or Alternative: Binary package).

Before installing, you may wish to check the tests, for example:

buildImagine/Imagine/Graphics/test/ImagineGraphicsTest

If the process fails somewhere, please check Troubleshooting.