Packages in VLE are autonomous projects which gather for example source code of PDEVS models, VPZ files, documentations or data. The goal of the packages in VLE is to improve the development of big models and to facilitate the sharing of models and code.

Example of a package hierarchy

  |─ buildvle/           ; the compilation directory,
  |                      ; it should not be directly modified
  |─ cmake/              ; cmake scripts
  |─ data/               ; data of your package
  |─ doc/                ; documentation of your package
  |─ exp/                ; experience, ie. vpz, of your package
  │   └─ CMakeLists.txt  ; CMake file of the directory exp
  │   └─ mymodel.vpz     ; your experiment (vpz file)
  |─ src/                ; directory of the source code
  │   └─ CMakeLists.txt  ; CMake file of the directory src
  │   └─ mydynamics.cpp  ; cpp code for your dynamics
  |                      ; (DEVS atomic model)
  |─ test/               ; directory containing the unit tests
  |                      ; for your package
  └─ Authors.txt         ; a Authors file
  └─ CMakeCPack.cmake    ; CMake packaging script
  └─ CMakeLists.txt      ; a root CMakeFile
  └─ Description.txt     ; a Description file
  └─ License.txt         ; a Licence file
  └─ News.txt            ; a News file
  └─ Readme.txt          ; a Readme file

A package or project in VLE have several directories and sub-directories. Although all files have their importance we will detail only the most important.

The VPZ files into the exp directory

A VPZ file represents a model and the experiment associated to the model. It can be simulated by vle application. It contains the structure of the model (seen as a graph) and inputs/outputs of the models. You can edit the model with the gvle application. The XML structure of this file is detailed here.

The Description.txt file

The Description.txt gives the description of the project. You should fill it with detailed informations about your package. There is an example of a Description.txt file :

Package: mypackage
Version: 0.1.0
Depends: vle.extension.decision, vle.extension.difference-equation
Build-Depends: vle.output
Maintainer: My name <mymail>
Description: Still in progress
Tags: examples
Url: http://mydistribution/
Size: 0
MD5sum: xxxx

You have to least to update the name of the package with the name of the directory (ie. mypackage). You can set a version to your package. The Depends tag should contain a list of packages you depend on for building your dynamics. For example if you use the vle extension for modelling difference equations (see VLE package distribution, it has to be listed. The Build-Depends should contain the list of packages you use (this time, without requiring them for the building process), typically it can be the vle.output package.

The cpp files into src directory

If you have the most integrated mode of use of VLE (using modelling plug ins into gvle, it is not required that you modify these files. They are generated by the modelling plug ins.

Each cpp files into src/ represents an atomic model. An atomic model is a C++ class that inherits from vle::devs::Dynacmis. Moreover a macro such as DECLARE_DYNAMICS has to be used in order to declare the class mentioned above to be a DEVS atomic model.

The CMakeLists.txt files

Once again, if you have the most integrated mode of use of VLE, it is not required that you modify these files.

These file are present in each subdirectory of a package. Depending on their location they have different roles. For examples the CMakeLists.txt file at the root directory declares the project and search for VLE includes and binaries. The CMakeLists.txt in src/ declares the C++ target to compile and to install.

How to manipulate VLE packages

In order to design the model the application gvle application is required. Designing the model means modifying the VPZ files of your package. These files are basically XML files and could be edited directly with a text editor; nevertheless gvle provides a gui to manipulate VPZ.

Otherwise in order to perform simulations, using the vle application in the package mode is sufficient. Also gvle provides some of these commands such as clean, rclean, configure, build and create.