freecad-cam/Mod/Draft/importAirfoilDAT.py
2026-02-01 01:59:24 +01:00

208 lines
6.5 KiB
Python

# -*- coding: utf-8 -*-
## @package importAirfoilDAT
# \ingroup DRAFT
# \brief Airfoil (.dat) file importer
#
# This module provides support for importing airfoil .dat files
'''@package importAirfoilDAT
Airfoil (.dat) file importer
This module provides support for importing airfoil .dat files.
'''
# Check code with
# flake8 --ignore=E226,E266,E401,W503
# ***************************************************************************
# * Copyright (c) 2010 Heiko Jakob <heiko.jakob@gediegos.de> *
# * *
# * This program is free software; you can redistribute it and/or modify *
# * it under the terms of the GNU Lesser General Public License (LGPL) *
# * as published by the Free Software Foundation; either version 2 of *
# * the License, or (at your option) any later version. *
# * for detail see the LICENCE text file. *
# * *
# * This program is distributed in the hope that it will be useful, *
# * but WITHOUT ANY WARRANTY; without even the implied warranty of *
# * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
# * GNU Library General Public License for more details. *
# * *
# * You should have received a copy of the GNU Library General Public *
# * License along with this program; if not, write to the Free Software *
# * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 *
# * USA *
# * *
# ***************************************************************************
__title__ = "FreeCAD Draft Workbench - Airfoil data importer"
__author__ = "Heiko Jakob <heiko.jakob@gediegos.de>"
__url__ = "https://www.freecad.org"
import re
import os
import FreeCAD
import Draft
import Part
from FreeCAD import Vector
from FreeCAD import Console as FCC
from draftutils.utils import pyopen
if FreeCAD.GuiUp:
from draftutils.translate import translate
else:
def translate(context, txt):
return txt
useDraftWire = True
def open(filename):
"""Open filename and parse.
Parameters
----------
filename : str
The path to the filename to be opened.
Returns
-------
App::Document
The new FreeCAD document object created, with the parsed information.
"""
docname = os.path.splitext(os.path.basename(filename))[0]
doc = FreeCAD.newDocument(docname)
doc.Label = docname
process(filename)
doc.recompute()
def insert(filename, docname):
"""Get an active document and parse.
If no document exists, it is created.
Parameters
----------
filename : str
The path to the filename to be opened.
docname : str
The name of the active App::Document if one exists, or
of the new one created.
Returns
-------
App::Document
The active FreeCAD document, or the document created if none exists,
with the parsed information.
"""
groupname = os.path.splitext(os.path.basename(filename))[0]
try:
doc = FreeCAD.getDocument(docname)
except NameError:
doc = FreeCAD.newDocument(docname)
obj = process(filename)
if obj is not None:
importgroup = doc.addObject("App::DocumentObjectGroup", groupname)
importgroup.Group = [obj]
doc.recompute()
def process(filename):
"""Process the filename and create a Draft Wire from the data.
The common airfoil dat format has many flavors.
This code should work with almost every dialect.
Parameters
----------
filename : str
The path to the filename to be opened.
Returns
-------
Part::Part2DObject or None.
The created Draft Wire object or None if the file contains less
than 3 points.
"""
# Regex to identify data rows and throw away unused metadata
xval = r'(?P<xval>\-?\s*\d*\.*\d*([Ee]\-?\d+)?)'
yval = r'(?P<yval>\-?\s*\d*\.*\d*([Ee]\-?\d+)?)'
_regex = r'^\s*' + xval + r'\,?\s*' + yval + r'\s*$'
regex = re.compile(_regex)
afile = pyopen(filename, 'r')
# read the airfoil name which is always at the first line
airfoilname = afile.readline().strip()
coords = []
# upside = True
# last_x = None
# Collect the data
for lin in afile:
curdat = regex.match(lin)
if (curdat is not None
and curdat.group("xval")
and curdat.group("yval")):
x = float(curdat.group("xval"))
y = float(curdat.group("yval"))
# Some files specify the number of upper and lower points on the 2nd line:
# " 67. 72."
# See: http://airfoiltools.com/airfoil
# This line must be skipped:
if x < 2 and y < 2:
# the normal processing
coords.append(Vector(x, y, 0))
afile.close()
if len(coords) < 3:
FCC.PrintError(translate("ImportAirfoilDAT", "Did not find enough coordinates") + "\n")
return None
# sometimes coords are divided in upper an lower side
# so that x-coordinate begin new from leading or trailing edge
# check for start coordinates in the middle of list
if coords[0:-1].count(coords[0]) > 1:
flippoint = coords.index(coords[0], 1)
upper = coords[0:flippoint]
lower = coords[flippoint+1:]
lower.reverse()
for i in lower:
upper.append(i)
coords = upper
# do we use the parametric Draft Wire?
if useDraftWire:
obj = Draft.make_wire(coords, True)
# obj.label = airfoilname
else:
# alternate solution, uses common Part Faces
lines = []
first_v = None
last_v = None
for v in coords:
if first_v is None:
first_v = v
# Line between v and last_v if they're not equal
if (last_v is not None) and (last_v != v):
lines.append(Part.makeLine(last_v, v))
# The new last_v
last_v = v
# close the wire if needed
if last_v != first_v:
lines.append(Part.makeLine(last_v, first_v))
wire = Part.Wire(lines)
face = Part.Face(wire)
obj = FreeCAD.ActiveDocument.addObject('Part::Feature', airfoilname)
obj.Shape = face
return obj