How to install MolTwister
Obtaining MolTwister
The first step is to download MolTwister. Goto the MolTwister homepage and select Download. You will be directed to the GitHub repository of MolTwister. The download can be done in two ways
Perform a git clone of the repository
Download the zip file of the repository
Git
Depending on the method used to download MolTwister, it may be necessary to install Git. On Ubuntu this is done by
sudo apt install git
On MacOS, Git can be installed using binary installers or through repositories, such as Homebrew. For example,
brew install git
GCC, G++ and CLang
MolTwister is written in C++. Hence, if GCC and G++ has not been installed, they must be installed. On Ubuntu, this can be done by
sudo apt install gcc
sudo apt install g++
On MacOS, MolTwister will be compiled using CLang. If CLang is not installed. make sure it is installed. This can be done by installing XCode.
CMake
To compile MolTwister, version 3.11, or greater, of CMake must be installed. On ubuntu, this can be done by
sudo apt install cmake
It is also possible to simplify the compilation process by installing cmake-gui:
sudo apt install cmake-gui
The GNU Readline Library
MolTwister uses the GNU Readline Library. The source code and binary files, in addition to installation instructions, are available at The GNU Readline Library home page. However, it is also possible (e.g., on Ubuntu) to install the development version through a repository:
sudo apt install libreadline-dev
The library is also avialable on repositories for MacOS and can be installed using Homebrew or MacPorts. For example,
brew install readline
Python/C
Python/C comes with Python and is used by MolTwister. On Ubuntu, this can be installed by
sudo apt install python3
sudo apt install libpython3-dev
Note that the Python3 package usually comes pre-installed on newer versions of Ubuntu. For MacOS, the Python3 package can be downloaded from python.org. It may also be necessary to install XCode to obtain the appropriate development libraries to compile Python/C specific code.
OpenGL
MolTwister uses OpenGL. Hence, the OpenGL development packages must be installed. On Ubuntu, this can be done by
sudo apt install libopengl-dev
sudo apt-get install libglu1-mesa-dev freeglut3-dev mesa-common-dev
If XCode is installed on MacOS, then development libraries for both OpenGL and the GLUT libraries should already be installed.
Compiling MolTwister
To compile MolTwister from the command line, goto the MolTwister source folder (where the CMakeLists.txt file resides). Then, type
cmake CMakeLists.txt -DINCLUDE_CUDA_COMMANDS=OFF
make
CUDA
To compile with GPU acceleration for the MD simulator in MolTwister, the latest CUDA development toolkit must be installed, together with appropriate drivers for the graphics card. To compile with cuda, use
cmake CMakeLists.txt -DINCLUDE_CUDA_COMMANDS=ON
make
There also exists a command line switch to enable debug code. This is achieved by adding
-DCUDA_DBG_INFO=ON
to the cmake call above.
Using QtCreator
It is recommended to use QtCreator as an IDE for the MolTwister project (since this has been tested extensively, both on MacOS and Ubuntu). The project is opened by choosing “Open Project” and selecting the CMakeLists.txt file. The first time the project is opened, the IDE will ask to configure the project. In that case, select “Desktop Qt x.y.z …” (for MacOS choose the clang 64bit compiler). A file called CMakeLists.txt.user will be created. If it becomes necessary to redo the configuration process, simply delete this file. To perform the cmake configuration right click the project and select “Run CMake” (usually happend automatically the first time the project is configured). After this, it is possible to right click and select “Build” or “Rebuild”.
On the menu that by default appears at the left hand side of the IDE window, there are a few options (”Welcome”, “Edit”, “Debug”, “Projects” and “Help”). Click on “Projects” and “Build” (under “Build & Run”). There, it is possible to select and deselect the INCLUDE_CUDA_COMMANDS and CUDA_DBG_INFO options. Activate the selection by clicking “Apply Configuration Changes”. Then, “Run CMake” and “Rebuild”.
On MacOS, it is important to goto Projects > Buid & Run > Run, from the left hand menu bar and tick “Run in Terminal”.
Installation of MolTwister
If MolTwister was compiled from the command line, make sure the working folder is the folder containing the source code (same folder as pulled from Git and
the same folder from where make
was called). In case QtCreater was used to build MolTwister, goto the build output folder created by QtCreator.
Usually, the output folder is created one level below the source folder. However, this is configurable through the QtCreator user interface. Then execute
sudo make install
This will install MolTwister as ‘moltwister’ under /usr/local/bin.
It should now be possible to execute the moltwister
command from any folder from within the command prompt, to start MolTwister.