Design document for the Morpho Gmsh Extension

gen.py

This file, under gmsh/api/gen.py, has the following structure:

// gen.py
from GenApi import * # Contains all the relevant objects and methods
...
api = API(version_major, version_minor, version_patch)

gmsh = api.add_module('gmsh', 'top-level functions')

doc = '''Initialize the Gmsh API ... ''' 
gmsh.add('initialize', doc, None, iargcargv(), ibool('readConfigFiles', 'true', 'True', 'true'), ibool('run', 'false', 'False'))

doc = '''Return 1 if the Gmsh API is initialized, and 0 if not.'''
gmsh.add('isInitialized', doc, oint)
...
option = gmsh.add_module('option', 'option handling functions')

doc = ''' ... '''
option.add(...)
...
model = gmsh.add_module('model', ...)
...
model.add('add', doc, None, istring('name'))
...
mesh = model.add_module('mesh', 'mesh functions') # Submodule of 'model'
...
api.write_c()
api.write_python()
...

Outline of gmsh/api/gen.py

The top level API object collects all the modules and submodules and writes them to various target languages. Its add_module method creates and returns a Module object, which has its own add_module method. The add method of the Module object takes in the name of the method, its documentation, the return type, and the input and output arguments. The I/O arguments are passed as objects of the arg class. Note that these are target-language agnostic (aside from providing default values for some languages), and the separate write methods of the API object handle the language-specific details. This allows gen.py to remain the same for all languages, and only the GenApi.py file needs to be modified for each language.

In light of this, we will aim to reuse the original gen.py as is, and only modify GenApi.py for our purposes.