New Plugin: Scripting

[elblake]

First release of the scripting plugin.

This plugin makes it possible to implement new shapes, importers, exporters and command scripts using scripting languages like Scheme and Python.

Requires Gauche for Scheme runtime
Requires Python 3.6 or later

Scripts

The locations of scripts are specified by the user in preferences, and each script comprises of the script itself (.py or .scm) and the .wscr file, which contains information about how the script should be called, and how to construct its parameter dialog box.

The .wscr file contains directives to add specific variables for use by the script, add configuation keys to the wings:import and wings:export functions for importer and exporter scripts. .wscr files also have a simple query language when using %[...], to access parameter values, and access values as tuples, lists, orddict, as well as store and retrieve the parameter values into temporary variables.

New shape scripts show up in the new shape menu. They use the same new_shape return value as plugins.

Importer and exporter scripts show up in the File > Import and File > Export menus.

Command scripts show up on right click on a selected object and can modify meshes in three different ways:

• Scripts can use a simplified API for simple tasks such as changing the vertex positions and colors.
• Scripts can receive an e3d_mesh object, modify it, and return a e3d_mesh back.
• Scripts can use we functions directly (wings_we, wings_face, wings_edge, wings_vertex, etc), the list of callable wings we functions is defined in callable.conf. This file also provides type information for the scripting plugin to convert
  lists to erlang data structures like sets and trees automatically.

Wings doesn't need to be restarted after modifying a script, the interpreter process is out-of-process and is started and closed on each invocation.

Script errors if any will show up in the wings console window.

Plugin Scripts

Plugin scripts are scripts that get added into wing's menu system so they can be accessed the same way as plugins. A script
(.py or .scm) and .wscr file can be bundled with a plugin script conf file and the three can be added to a folder in the user folder called "plugin_scripts" and the script will show up with its own menu entry in the right click menus. This makes it so a script can be packaged for distribution and installed like an actual plugin. The "Install Plugin" menu has had changes made so plugins can be queried when a tar file is being installed which does not contain a beam file.

Script Folders

Script folder conf files are added in a user folder called "script_folders" and this makes it so a folder of scripts can be made into a submenu in the wings program. It's similar to the plugin script conf file, but more for power users to have separate script folders in
different menus in wings.

Documentation

The scripting plugin adds information and a reference manual to the help menu. The reference manual contains information for python scripts, scheme scripts and the .wscr config file.

The we function documentation is generated from the funs file in the docs folder.

Changes to Wings

The pull request makes changes to wings_dialog, wings_plugin, and wings_va:

wings_dialog:
A new documentation system built on top of the current help text window in wings_dialog was created for the scripting documentation.

wings_plugin:
The "Install Plugin" menu item has been changed so that when a tar file does not contain a beam file, but does contain an XML file containing a type string, wings will query loaded plugins for one that recognize the type string.

wings_va:
Added set_face_attr_vs/4 to wings_va to change point vertex attributes using the same list data structure that is returned from face_attr/3.

Added replace_attr/3 to wings_va.

New tools added in the tools folder:

tools/pack_manual is a script for creating manuals, it can be used for future references for other plugins as well.

Credits

Earlier version of the scripting preference dialog used wxDialog API directly, the plugin preference dialog had been rewritten to now use wings ui dialog, many thanks to Micheus help to change it over.

NOTE: Added scripting to wings.