Assuming that you have the source tree at /path/to/gismo, here is how to use G+Smo in your application:

• Choose a folder for building (eg. folder /path/to/build for demonstation):

mkdir /path/to/build cd /path/to/build

Note: If you only need to experiment with a small main.cpp file, the far easiest way to go is to copy the file "main.cpp" to the source folder gismo/examples. Then issue:

cmake /path/to/gismo make -j2 main ./bin/main Hello G+Smo.

After executing cmake, the file is included directly to the "examples" compilation list, and the binary file is created in the subfolder ./bin. However, if you need to use the library as an external dependency, then continue reading these instructions.

• Configure, build and install on a predefined location (eg. ./path/to/install for demonstration):

The configure step: cmake /path/to/gismo -DCMAKE_INSTALL_PREFIX=/path/to/install -DGISMO_EXAMPLES=OFF

The build step:

make -j2

Note that here we assume that Makefiles were used (autotools). We could explicitly choose a builder during configuration or CMake will resort to an available builder in the system. Another popular builder is ninja, in which case we would always issue "ninja" instead of "make".

The install step (optional), requires that the build step above succeeded:

make -j2 install

The installation will create the folder /path/to/install, containing:

• ./include/gismo Include path needed by the library (eg. gismo.h)
• ./lib Shared library (eg. libgismo.so)
• ./bin Compiled examples (only if GISMO_EXAMPLES=ON)

During development that might also involve frequent re-building of G+Smo the install step would have to be executed after each build. Therefore one could also skip this step and use the build folder to deploy the library to an external project.

There are several solutions for using the library in your project:

• Solution 1: use the provided main.cpp and CMakeLists.txt (recommended)

Copy the provided "CMakeLists.txt" and main.cpp to a folder of your choice. In that folder issue:

We can point our new project directly to the build folder (eg. if install was not executed):

cd /path/to/myproject cmake . -Dgismo_DIR=/path/to/build

Alternatively, if we would like to point to our install location the path would change:

cmake . -Dgismo_DIR=/path/to/install

This will create a "Makefile" (therefore will overwrite any existing makefiles). For this solution the installation of G+Smo is not mandatory.

It is important to see in the output of CMake the message:

"G+Smo shared library found in /some/path"

This reveals the actual dynamic or static library file that will be used for linking. If the path is not the one instructed in gsimo_DIR, then we might need to remove the CMakeCache.txt file and try again. Another complication might be that CMake usually "remembers" a specific build location and uses that one, eg. when we do not explicitly set gismo_DIR or the path we set is not correct. In that case we should delete the cache file (CMakeCache.txt) and also remove the following folder:

rm -rf ~/.cmake/packages/gismo

and restart the process.

If the configuration is successfull, then typing "make" should create the binary file "main", which can be executed as:

make ./main Hello G+Smo.

Note A: CMake can produce project files for Visual Studio, Ninja, CodeBlocks, and many other build systems, see https://cmake.org/cmake/help/v3.0/manual/cmake-generators.7.html.

Note B: On Windows (but also linux), we can use the graphical tool cmake-gui to configure and compile. On linux the interactive tool ccmake is also an option.

• Solution 2: use the provided main.cpp and Makefile (in unix-based systems)

Copy the provided "Makefile" and main.cpp to a folder of your choice. You need to edit the Makefile and update the variable GISMODIR to point to your install directory where G+Smo is found:

GISMODIR :=/path/to/install

Then typing "make" should create the binary file "main", which can be executed as:

make ./main Hello G+Smo.

• Solution 3: Run your favorite compiler, eg. GCC, and link with libgismo.so:

If installation was performed, then we can also use:

g++ main.cpp -I/path/to/install/include/gismo -L/path/to/install/lib -Wl,-rpath=/path/to/install/lib -lgismo -o main ./main Hello G+Smo.

Or, on Windows, using the Microsoft compiler on a developer command prompt:

cl /EHsc main.cpp /I C:\path\to\install\include\gismo /link C:\path\to\install\lib\gismo.lib main.exe Hello G+Smo.