Workbench creation/ru

Вступление
This page will show you how to add a new workbench to the FreeCAD interface. Workbenches are containers for FreeCAD commands. They can be coded in Python, in C++, or in a mix of both, which has the advantage to ally the speed of C++ to the flexibility of Python. In all cases, though, your workbench will be launched by a set of two Python files. They can be "internal" workbenches, included with FreeCAD's distribution, or "external" workbenches, distributed via the Addon Manager or installed manually by downloading from some online repository. Internal workbenches may be coded in either C++, Python, or a combination of the two, whereas external workbenches must be Python-only.

Структура Верстака
You need a folder, with any name you like, placed in the user Mod directory, with an file, and, optionally an  file. The Init file is executed when FreeCAD starts, and the file is executed immediately after, but only when FreeCAD starts in GUI mode. That's all it needs for FreeCAD to find your workbench at startup and add it to its interface.

The user Mod directory is a sub-directory of the user application data directory (you can find the latter by typing in the Python console):
 * On Linux it is usually.
 * On Windows it is, which is usually.
 * On macOS it is usually.

Mod папка должна выглядеть так:

Внутри этих файлов вы можете делать все, что захотите. Обычно они используются таким образом:


 * В Init.py файл вы просто добавляете пару вещей, которые используются даже тогда, когда FreeCAD работает в консольном режиме, например таке как, импортеры и экспортеры файлов.


 * В InitGui.py файле вы инициализируете Верстак, который содержит имя, значок и ряд команд FreeCAD (см. Ниже). Этот python файл также должен иметь определенные функции, первая выполняется при загрузке FreeCAD (стараетесь делать ее как можно меньше, чтобы не замедлять запуск), еще одну, которая выполняется при активации верстака (именно там выполняется большая часть работы), и третью, когда верстак деактивирован (чтобы при необходимости можно было осободить ненужные ресурсы).

The structure and file content for a workbench described here is the classic way of creating a new workbench. One can use a slight variation in the structure of files when making a new Python workbench, that alternative way is best described as a "namespaced workbench", opening up the possibility to use pip to install the workbench. Both structures work, so it is more a question of preference when creating a new workbench. The style and structure for workbenches presented here are available in the global namespace of FreeCAD, whereas for the alternative style and structure the workbench resides in a dedicated namespace. For further readings on the topic see Related.

Структура Верстака на языке C++
Если вы собираетесь писать свой Верстак на python, вам не нужно проявлять особую осторожность, и вы можете просто разместить другие файлы python в папке с Init.py и InitGui.py. Однако при работе с C++ вам следует проявлять большую осторожность и начинать соблюдюдать одно фундаментальное правило FreeCAD: Разделение вашего рабочего стола между частью приложения (которая может работать в режиме консоли, без какого-либо элемента графического интерфейса) и частью графического интерфейса, которая будет загружена только при запуске FreeCAD с полной графической средой. Поэтому при создании рабочей среды в C++ вы, скорее всего, будете использовать два модуля: модуль самого приложения и модуль графического интерфейса. Эти два модуля, конечно, должны быть вызываемы из python. Любой модуль FreeCAD (приложение или графический интерфейс) состоит, по крайней мере, из файла инициализации модуля. Это типичный AppMyModuleGui.cpp файл:

Файл Init.py
You can choose any license you like for your workbench, but be aware that if you wish to see your workbench integrated into and distributed with the FreeCAD source code at some point, it needs to be LGPL2+ like the example above. See Licence.

The and  functions allow you to give the name and extension of a file type, and a Python module responsible for its import. In the example above, an module will handle  files. See Code snippets for more examples.

Python workbenches
This is the InitGui.py file:

Other than that, you can do anything you want: you could put your whole workbench code inside the InitGui.py if you want, but it is usually more convenient to place the different functions of your workbench in separate files. So those files are smaller and easier to read. Then you import those files into your InitGui.py file. You can organize those files the way you want, a good example is one for each FreeCAD command you add.

Preferences
You can add a Preferences page for your Python workbench. The Preferences pages look for a preference icon with a specific name in the Qt Resource system. If your icon isn't in the resource system or doesn't have the correct name, your icon won't appear on the Preferences page.

Adding your workbench icon:
 * the preferences icon needs to be named "preferences-" + "modulename" + ".svg" (all lowercase)
 * make a qrc file containing all icon names
 * in the main *.py directory, run pyside-rcc -o myResources.py myqrc.qrc
 * in InitGui.py, add import myResource(.py)
 * update your repository(git) with myResources.py and myqrc.qrc

You'll need to redo the steps if you add/change icons.

@kbwbe has created a nice script to compile resources for the A2Plus workbench. See below.

Adding your preference page(s):
 * You need to compile the Qt designer plugin that allows you to add preference settings with Qt Designer
 * Create a blank widget in Qt Designer (no buttons or anything)
 * Design your preference page, any setting that must be saved (preferences) must be one of the Gui::Pref* widgets that were added by the plugin)
 * In any of those, make sure you fill the PrefName (the name of your preference value) and PrefPath (ex: Mod/MyWorkbenchName), which will save your value under BaseApp/Preferences/Mod/MyWorkbenchName
 * Save the ui file in your workbench, make sure it's handled by cmake
 * In your workbench, for ex. inside the InitGui file, inside the Initialize method (but any other place works too), add: FreeCADGui.addPreferencePage("/path/to/myUiFile.ui","MyGroup"), "MyGroup" being one of the preferences groups on the left. FreeCAD will automatically look for a "preferences-mygroup.svg" file in its known locations (which you can extend with FreeCADGui.addIconPath)
 * Make sure the addPreferencePage method is called only once, otherwise your pref page will be added several times

Distribution
To distribute your Python workbench, you may either simply host the files in some location and instruct your users to download them and place them in their Mod directory manually, or you may host them in an online git repository (GitHub, GitLab, Framagit, and Debian Salsa are currently supported locations) and configure them for the Addon Manager to install. Instructions for inclusion on FreeCAD's official Addons list can be found on the FreeCAD Addons GitHub repository. To use the Addon Manager, a package.xml metadata file should be included, which instructs the Addon Manager how to find your workbench's icon, and allows display of a description, version number, etc. It can also be used to specify other external Addons that your Workbench either depends on, is blocked by, or is intended to replace.

Optionally, you can include a metadata file describing your Python dependencies. This may be either a file called metadata.txt describing your workbench's external dependencies (on either other Addons, Workbenches, or Python modules), or a requirements.txt describing your Python dependencies. Note that if using a requirements.txt file, only the names of the specified packages are used for dependency resolution: pip command options, include options and version information are not supported by the Addon Manager. Users may manually run the requirements file using pip if those features are required.

The format of the metadata.txt file is plain text, with three optional lines:

Each line should consist of a comma-separated list of items your Workbench depends on. Workbenches may be either an internal FreeCAD Workbench, e.g. "FEM", or an external Addon, for example "Curves". The required and optional Python libraries should be specified with their canonical Python names, such as you would use with. For example:

You may also include a script that is run when your package is uninstalled. This is a file called "uninstall.py" located at the top level of your Addon. It is executed when a user uninstalls your Addon using the Addon Manager. Use it to clean up anything your Addon may have done to the users system that should not persist when the Addon is gone (e.g. removing cache files, etc.).

C++ workbenches
If you are going to code your workbench in C++, you will probably want to code the workbench definition itself in C++ too (although it is not necessary: you could also code only the tools in C++, and leave the workbench definition in Python). In that case, the InitGui.py file becomes very simple: It might contain just one line:

where MyModule is your complete C++ workbench, including the commands and workbench definition.

Coding C++ workbenches works in a pretty similar way. This is a typical Workbench.cpp file to include in the Gui part of your module:

Preferences
You can add a Preferences page for C++ workbenches too. The steps are similar to those for Python.

FreeCAD commands
FreeCAD commands are the basic building block of the FreeCAD interface. They can appear as a button on toolbars, and as a menu entry in menus. But it is the same command. A command is a simple Python class, that must contain a couple of predefined attributes and functions, that define the name of the command, its icon, and what to do when the command is activated.

C++ command definition
Similarly, you can code your commands in C++, typically have a Commands.cpp file in your Gui module. This is a typical Commands.cpp file:

"Compiling" your resource file
compileA2pResources.py from the A2Plus workbench:

Related

 * Translating an external workbench
 * Namespaced Workbenches - discussion
 * freecad.workbench_starterkit