src/Mod/OpenSCAD/OpenSCADUtils.py

# SPDX-License-Identifier: LGPL-2.1-or-later
#***************************************************************************
#*   Copyright (c) 2012 Sebastian Hoogen <github@sebastianhoogen.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                                                                   *
#*                                                                         *
#***************************************************************************

""" This Script includes various python helper functions that are shared across the
module."""

import io
import itertools
import os
import shutil
import sys
import subprocess
import tempfile
import time

from exportCSG import mesh2polyhedron
import FreeCAD
import Part
import Mesh
import MeshPart
import importDXF

__title__ = "FreeCAD OpenSCAD Workbench - Utility Functions"
__author__ = "Sebastian Hoogen"
__url__ = ["https://www.freecad.org"]

translate = FreeCAD.Qt.translate

try:
    BaseError = FreeCAD.Base.FreeCADError
except (ImportError, AttributeError):
    BaseError = RuntimeError


class OpenSCADError(BaseError):
    def __init__(self, value):
        self.value = value

    def __str__(self):
        return repr(self.value)


def getopenscadexe(osfilename=None):
    if not osfilename:
        osfilename = FreeCAD.ParamGet(\
            "User parameter:BaseApp/Preferences/Mod/OpenSCAD").\
            GetString('openscadexecutable')
    if osfilename and os.path.isfile(osfilename):
        return osfilename
    return searchforopenscadexe()


def searchforopenscadexe():
    """Try to use Python's built-in executable-finder. If that fails, fall back to the
    old code."""
    py3_find = shutil.which("openscad")
    if py3_find:
        return py3_find
    FreeCAD.Console.PrintError(
        "shutil.which('openscad') did not return a result. Using fallback.\n"
    )
    # The code that follows is from the original OpenSCAD WB code, kept around until we
    # can verify that all of our expected systems work with the shutil call. -CH 2/23
    if sys.platform == 'win32':
        testpaths = [os.path.join(os.environ.get('Programfiles(x86)','C:'),\
            'OpenSCAD\\openscad.exe')]
        if 'ProgramW6432' in os.environ:
            testpaths.append(os.path.join(os.environ.get('ProgramW6432','C:')\
                ,'OpenSCAD\\openscad.exe'))
        for testpath in testpaths:
            if os.path.isfile(testpath):
                return testpath
    elif sys.platform == 'darwin':
        ascript = (b'tell application "Finder"\n'
                   b'POSIX path of (application file id "org.openscad.OpenSCAD"'
                   b'as alias)\n'
                   b'end tell')
        p1=subprocess.Popen(['osascript', '-'], stdin=subprocess.PIPE,\
                stdout=subprocess.PIPE,stderr=subprocess.PIPE)
        stdout, stderr = p1.communicate(ascript)
        if p1.returncode == 0:
            opathl = stdout.decode().split('\n')
            if len(opathl) >= 1:
                return opathl[0]+'Contents/MacOS/OpenSCAD'
        #test the default path
        testpath="/Applications/OpenSCAD.app/Contents/MacOS/OpenSCAD"
        if os.path.isfile(testpath):
            return testpath
    else: #unix
        p1 = subprocess.Popen(['which','openscad'], stdout=subprocess.PIPE)
        if p1.wait() == 0:
            output = p1.stdout.read()
            output = output.decode("utf-8")
            opath = output.split('\n')[0]
            return opath


def getopenscadversion(osfilename=None):
    if not osfilename:
        osfilename = getopenscadexe()
    if osfilename and os.path.isfile(osfilename):
        with subprocess.Popen([osfilename, '-v'],\
            stdout = subprocess.PIPE,stderr=subprocess.PIPE, universal_newlines=True) as p:
            p.wait()
            stdout = p.stdout.read().strip()
            stderr = p.stderr.read().strip()
            return (stdout or stderr)


def newtempfilename():
    formatstr = 'fc-%05d-%06d-%06d'
    count = 0
    while True:
        count += 1
        yield formatstr % (os.getpid(), int(time.time()*100) % 1000000, count)

tempfilenamegen = newtempfilename()


def callopenscad(inputfilename,outputfilename=None, outputext='csg', keepname=False):
    '''call the open scad binary
    returns the filename of the result (or None),
    please delete the file afterwards'''

    def check_output2(*args, **kwargs):
        kwargs.update({'stdout':subprocess.PIPE,'stderr':subprocess.PIPE})
        p = subprocess.Popen(*args, **kwargs)
        stdoutd, stderrd = p.communicate()
        stdoutd = stdoutd.decode("utf8")
        stderrd = stderrd.decode("utf8")
        if p.returncode != 0:
            raise OpenSCADError('%s %s\n' % (stdoutd.strip(),stderrd.strip()))
            #raise Exception,'stdout %s\n stderr%s' %(stdoutd,stderrd)
        if stderrd.strip():
            FreeCAD.Console.PrintWarning(stderrd + '\n')
        if stdoutd.strip():
            FreeCAD.Console.PrintMessage(stdoutd + '\n')
            return stdoutd

    preferences = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Mod/OpenSCAD")
    osfilename = getopenscadexe()
    transferMechanism = preferences.GetInt('transfermechanism',0)
    if transferMechanism == 0: # Use the Python temp-directory creation function
        transferDirectory = tempfile.gettempdir()
    elif transferMechanism == 1: # Use a user-specified directory for the transfer
        transferDirectory = preferences.GetString('transferdirectory')
    elif transferMechanism ==  2: # Use pipes instead of tempfiles
        return call_openscad_with_pipes(inputfilename, outputfilename, outputext, keepname)
    else:
        raise OpenSCADError("Invalid transfer mechanism specified")

    if osfilename and os.path.isfile(osfilename):
        if not outputfilename:

            dir1 = transferDirectory
            if keepname:
                outputfilename = os.path.join(dir1, '%s.%s' % (os.path.split(\
                    inputfilename)[1].rsplit('.',1)[0],outputext))
            else:
                outputfilename = os.path.join(dir1,'%s.%s' % \
                    (next(tempfilenamegen),outputext))
        check_output2([osfilename, '-o', outputfilename, inputfilename])
        return outputfilename
    else:
        raise OpenSCADError('OpenSCAD executable unavailable')


def call_openscad_with_pipes(input_filename, output_filename, output_extension, keep_name):
    ''' Call OpenSCAD by sending input data to stdin, and read the output from stdout.
        Returns the tempfile the output is stored in on success, or None on failure.
        NOTE: This feature was added to OpenSCAD in 2021.01'''

    # For testing purposes continue using temp files, but now OpenSCAD does not need
    # read or write access to the files, only the FreeCAD process does. In the future
    # this could be changed to keep everything in memory, if desired.
    transfer_directory = tempfile.gettempdir()

    # Load the data back in from our tempfile:
    with open(input_filename) as datafile:
        openscad_data = datafile.read()
        # On the command line this looks like:
        #   $ cat myfile.scad | openscad --export-format csg -o - -
        p = subprocess.Popen([getopenscadexe(), "--export-format", "csg", "-o", "-", "-"],
                             stdin=subprocess.PIPE,
                             stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE)
        stdoutd,stderrd = p.communicate (input = openscad_data.encode('utf8'), timeout=15)
        stdoutd = stdoutd.decode("utf8")
        stderrd = stderrd.decode("utf8")
        if p.returncode != 0:
            raise OpenSCADError('%s %s\n' % (stdoutd.strip(),stderrd.strip()))

        if not output_filename:
            dir1 = transfer_directory
            if keep_name:
                output_filename=os.path.join(dir1,'%s.%s' % (os.path.split(\
                    input_filename)[1].rsplit('.',1)[0],output_extension))
            else:
                output_filename=os.path.join(dir1,'%s.%s' % \
                    (next(tempfilenamegen),output_extension))
        with open(output_filename,"w") as outfile:
            outfile.write(stdoutd)
            return output_filename


def callopenscadstring(scadstr,outputext='csg'):
    '''create a tempfile and call the open scad binary
    returns the filename of the result (or None),
    please delete the file afterwards'''
    dir1 = tempfile.gettempdir()
    inputfilename = os.path.join(dir1,'%s.scad' % next(tempfilenamegen))
    inputfile = io.open(inputfilename,'w', encoding="utf8")
    inputfile.write(scadstr)
    inputfile.close()
    outputfilename = callopenscad(inputfilename, outputext=outputext,\
        keepname=True)
    os.unlink(inputfilename)
    return outputfilename


def reverseimporttypes():
    '''allows one to search for supported filetypes by module'''

    def getsetfromdict(dict1, index):
        if index in dict1:
            return dict1[index]
        else:
            set1=set()
            dict1[index]=set1
            return set1

    importtypes = {}
    for key,value in FreeCAD.getImportType().items():
        if type(value) is str:
            getsetfromdict(importtypes,value).add(key)
        else:
            for vitem in value:
                getsetfromdict(importtypes,vitem).add(key)
    return importtypes


def fcsubmatrix(m):
    """Extracts the 3x3 Submatrix from a freecad Matrix Object
    as a list of row vectors"""
    return [[m.A11,m.A12,m.A13],[m.A21,m.A22,m.A23],[m.A31,m.A32,m.A33]]


def multiplymat(l, r):
    """multiply matrices given as lists of row vectors"""
    rt = zip(*r) #transpose r
    rt = list(rt)
    mat=[]
    for y in range(len(rt)):
        mline=[]
        for x in range(len(l)):
            mline.append(sum([le*re for le,re in zip(l[y],rt[x])]))
        mat.append(mline)
    return mat


def isorthogonal(submatrix, precision=4):
    """checking if 3x3 Matrix is orthogonal (M*Transp(M)==I)"""
    prod = multiplymat(submatrix,list(zip(*submatrix)))
    return [[round(f,precision) for f in line] \
        for line in prod] == [[1,0,0],[0,1,0],[0,0,1]]


def detsubmatrix(s):
    """get the determinant of a 3x3 Matrix given as list of row vectors"""
    return s[0][0]*s[1][1]*s[2][2]+s[0][1]*s[1][2]*s[2][0]+\
           s[0][2]*s[1][0]*s[2][1]-s[2][0]*s[1][1]*s[0][2]-\
           s[2][1]*s[1][2]*s[0][0]-s[2][2]*s[1][0]*s[0][1]

def isspecialorthogonalpython(submat, precision=4):
    return isorthogonal(submat,precision) and round(detsubmatrix(submat),precision) == 1

def isrotoinversionpython(submat, precision=4):
    return isorthogonal(submat,precision) and round(detsubmatrix(submat),precision) == -1

def isspecialorthogonal(mat, precision=4):
    return abs(mat.submatrix(3).isOrthogonal(10**(-precision))-1.0) < \
            10**(-precision) and \
            abs(mat.submatrix(3).determinant()-1.0) < 10**(-precision)


def decomposerotoinversion(m, precision=4):
    rmat = [[round(f,precision) for f in line] for line in fcsubmatrix(m)]
    cmat = FreeCAD.Matrix()
    if rmat == [[-1,0,0],[0,1,0],[0,0,1]]:
        cmat.scale(-1,1,1)
        return m*cmat,FreeCAD.Vector(1)
    elif rmat == [[1,0,0],[0,-1,0],[0,0,1]]:
        cmat.scale(1,-1,1)
        return m*cmat, FreeCAD.Vector(0,1)
    elif rmat == [[1,0,0],[0,1,0],[0,0,-1]]:
        cmat.scale(1,1,-1)
        return m*cmat, FreeCAD.Vector(0,0,1)
    else:
        cmat.scale(1,1,-1)
        return m*cmat, FreeCAD.Vector(0,0,1)


def mirror2mat(nv, bv):
    """calculate the transformation matrix of a mirror feature"""
    mbef = FreeCAD.Matrix()
    mbef.move(bv * -1)
    maft = FreeCAD.Matrix()
    maft.move(bv)
    return maft*vec2householder(nv)*mbef


def vec2householder(nv):
    """calculated the householder matrix for a given normal vector"""
    lnv = nv.dot(nv)
    l = 2/lnv if lnv > 0 else 0
    hh = FreeCAD.Matrix(nv.x*nv.x*l,nv.x*nv.y*l,nv.x*nv.z*l,0,\
                      nv.y*nv.x*l,nv.y*nv.y*l,nv.y*nv.z*l,0,\
                      nv.z*nv.x*l,nv.z*nv.y*l,nv.z*nv.z*l,0,0,0,0,0)
    return FreeCAD.Matrix()-hh


def mirrormesh(msh, vec):
    """mirrormesh(mesh,vector) where mesh is a mesh object and vector is a Base.Vector"""
    poly = mesh2polyhedron(msh)
    vec_string = '['+str(vec.x)+','+str(vec.y)+','+str(vec.z)+']'
    param = 'mirror('+vec_string+')'
    mi = callopenscadmeshstring('%s{%s}' % (param,''.join(poly)))
    mi.flipNormals()
    return mi


def scalemesh(msh, vec):
    """scalemesh(mesh,vector) where mesh is a mesh object and vector is a Base.Vector"""
    poly = mesh2polyhedron(msh)
    vec_string = '['+str(vec.x)+','+str(vec.y)+','+str(vec.z)+']'
    param = 'scale('+vec_string+')'
    mi = callopenscadmeshstring('%s{%s}' % (param,''.join(poly)))
    mi.flipNormals()
    return mi


def resizemesh(msh, vec):
    """resizemesh(mesh,vector) where mesh is a mesh object and vector is a Base.Vector"""
    poly = mesh2polyhedron(msh)
    vec_string = '['+str(vec.x)+','+str(vec.y)+','+str(vec.z)+']'
    param = 'resize('+vec_string+')'
    mi = callopenscadmeshstring('%s{%s}' % (param,''.join(poly)))
    mi.flipNormals()
    return mi


def angneg(d):
    return d if (d <= 180.0) else (d-360)


def shorthexfloat(f):
    mantisse, exponent = f.hex().split('p',1)
    return '%sp%s' % (mantisse.rstrip('0'),exponent)


def comparerotations(r1,r2):
    '''compares two rotations
    a value of zero means that they are identical'''
    r2c = FreeCAD.Rotation(r2)
    r2c.invert()
    return r1.multiply(r2c).Angle

def findbestmatchingrotation(r1):
    vangl = \
(1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 11.25, 12.0, 13.0,
14.0, 15.0, 16.0, (180.0/11.0), 17.0, 18.0, 19.0, 20.0, 21.0, 22.0, 22.5,
23.0, 24.0, 25.0, 26.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, (360.0/11.0),
33.0, 33.75, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0,
44.0, 45.0, 46.0, 47.0, 48.0, 49.0,(540.0/11.0), 50.0, 51.0, (360.0/7.0),
52.0, 53.0, 54.0, 55.0, 56.0, 56.25, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0,
63.0, 64.0, 65.0,(720.0/11.0), 66.0, 67.0, 67.5, 68.0, 69.0, 70.0, 71.0,
72.0, 73.0, 74.0, 75.0, 76.0, 77.0, 78.0, 78.75, 79.0, 80.0, 81.0,(900.0/11.0),
82.0, 83.0, 84.0, 85.0, 86.0, 87.0, 88.0, 89.0, 90.0, 91.0, 92.0, 93.0, 94.0,
95.0, 96.0, 97.0, 98.0,(1080.0/11.0), 99.0, 100.0, 101.0, 101.25, 102.0,
(720.0/7.0), 103.0, 104.0, 105.0, 106.0, 107.0, 108.0, 109.0, 110.0, 111.0,
112.0, 112.5, 113.0, 114.0, (1260.0/11), 115.0, 116.0, 117.0, 118.0, 119.0,
120.0, 121.0, 122.0, 123.0, 123.75, 124.0, 125.0, 126.0, 127.0, 128.0,
 129.0, 130.0,(1440.0/11.0), 131.0, 132.0, 133.0, 134.0, 135.0, 136.0,
137.0, 138.0, 139.0, 140.0, 141.0, 142.0, 143.0, 144.0, 145.0, 146.0, 146.25,
147.0, (1620.0/11.0), 148.0, 149.0, 150.0, 151.0, 152.0, 153.0, 154.0,
(1080.0/7.0), 155.0, 156.0, 157.0, 157.5, 158.0, 159.0, 160.0, 161.0, 162.0,
163.0, (1800.0/11.0), 164.0, 165.0, 166.0, 167.0, 168.0, 168.75, 169.0, 170.0,
171.0, 172.0, 173.0, 174.0, 175.0, 176.0, 177.0,178.0, 179.0,180.0,
-179.0, -178.0, -177.0, -176.0, -175.0, -174.0, -173.0, -172.0, -171.0, -170.0,
-169.0, -168.75, -168.0, -167.0, -166.0, -165.0, -164.0, (-1800.0/11.0),
-163.0, -162.0, -161.0, -160.0, -159.0, -158.0, -157.5, -157.0, -156.0,
-155.0, (-1080.0/7.0), -154.0, -153.0, -152.0, -151.0, -150.0, -149.0, -148.0,
(-1620.0/11.0), -147.0, -146.25, -146.0, -145.0, -144.0, -143.0, -142.0,
-141.0, -140.0, -139.0,-138.0, -137.0, -136.0, -135.0, -134.0, -133.0, -132.0,
 -131.0, (-1440/11.0), -130.0, -129.0, -128.0,-127.0, -126.0, -125.0, -124.0,
 -123.75, -123.0, -122.0, -121.0, -120.0, -119.0, -118.0, -117.0, -116.0,
-115.0,(-1260.0/11.0), -114.0, -113.0, -112.5, -112.0, -111.0, -110.0, -109.0,
-108.0, -107.0, -106.0, -105.0,-104.0, -103.0,(-720.0/7.0), -102.0, -101.25,
-101.0, -100.0, -99.0, (-1080.0/11.0), -98.0, -97.0, -96.0, -95.0, -94.0,
-93.0, -92.0, -91.0, -90.0, -89.0, -88.0, -87.0, -86.0, -85.0, -84.0, -83.0,
-82.0,(-900.0/11.0), -81.0, -80.0, -79.0, -78.75, -78.0, -77.0, -76.0, -75.0,
-74.0, -73.0, -72.0, -71.0, -70.0, -69.0, -68.0, -67.5, -67.0, -66.0,
(-720.0/11.0), -65.0, -64.0, -63.0, -62.0, -61.0, -60.0, -59.0, -58.0, -57.0,
-56.25, -56.0, -55.0, -54.0, -53.0, -52.0,(-360.0/7.0), -51.0, -50.0,
(-540.0/11.0), -49.0, -48.0, -47.0, -46.0, -45.0, -44.0, -43.0, -42.0, -41.0,
-40.0, -39.0, -38.0, -37.0, -36.0, -35.0, -34.0, -33.75, -33.0,(-360.0/11.0),
-32.0, -31.0, -30.0, -29.0, -28.0, -27.0, -26.0, -25.0, -24.0, -23.0, -22.5,
-22.0, -21.0, -20.0, -19.0, -18.0, -17.0,(-180.0/11.0), -16.0, -15.0, -14.0,
-13.0, -12.0, -11.25, -11.0, -10.0, -9.0, -8.0, -7.0, -6.0, -5.0, -4.0, -3.0,
-2.0, -1.0)
    def tup2nvect(tup):
        """convert a tuple to a normalized vector"""
        v = FreeCAD.Vector(*tup)
        v.normalize()
        return v


    def wkaxes():
        """well known axes for rotations"""
        vtupl=((1,0,0),(0,1,0),(0,0,1),
            (1,1,0),(1,0,1),(0,1,1),(-1,1,0),(-1,0,1),(0,1,-1),
            (1,1,1),(1,1,-1),(1,-1,1),(-1,1,1))
        return tuple(tup2nvect(tup) for tup in vtupl)

    bestrot = FreeCAD.Rotation()
    dangle  = comparerotations(r1, bestrot)
    for axis in wkaxes():
        for angle in vangl:
            for axissign in (1.0,-1.0):
                r2=FreeCAD.Rotation(axis*axissign, angle)
                dangletest = comparerotations(r1,r2)
                if dangletest < dangle:
                    bestrot = r2
                    dangle = dangletest
    return (bestrot,dangle)


def roundrotation(rot, maxangulardistance=1e-5):
    '''guess the rotation axis and angle for a rotation
    recreated from rounded floating point values
    (from a quaterion or transformation matrix)'''
    def teststandardrot(r1, maxangulardistance=1e-5):
        '''test a few common rotations beforehand'''
        eulers = []
        for angle in (90,-90,180,45,-45,135,-135):
            for euler in itertools.permutations((0,0,angle)):
                eulers.append(euler)
        for euler in itertools.product((0,45,90,135,180,-45,-90,-135), repeat=3):
            eulers.append(euler)
        for euler in eulers:
            r2 = FreeCAD.Rotation(*euler)
            if comparerotations(r1, r2) < maxangulardistance:
                return r2

    if rot.isNull():
        return rot
    firstguess = teststandardrot(rot,maxangulardistance)
    if firstguess is not None:
        return firstguess
    #brute force
    bestguess,angulardistance = findbestmatchingrotation(rot)
    if angulardistance < maxangulardistance: #use guess
        return bestguess
    else: #use original
        return rot


def callopenscadmeshstring(scadstr):
    """Call OpenSCAD and return the result as a Mesh"""
    tmpfilename = callopenscadstring(scadstr, 'stl')
    newmesh = Mesh.Mesh()
    newmesh.read(tmpfilename)
    try:
        os.unlink(tmpfilename)
    except OSError:
        pass
    return newmesh


def meshopinline(opname, iterable1):
    """uses OpenSCAD to combine meshes
    takes the name of the CGAL operation and an iterable (tuple,list) of
    FreeCAD Mesh objects
    includes all the mesh data in the SCAD file
    """
    return callopenscadmeshstring('%s(){%s}' % (opname,' '.join(\
        (mesh2polyhedron(meshobj) for meshobj in iterable1))))


def meshoptempfile(opname, iterable1):
    """uses OpenSCAD to combine meshes
    takes the name of the CGAL operation and an iterable (tuple,list) of
    FreeCAD Mesh objects
    uses stl files to supply the mesh data
    """
    dir1 = tempfile.gettempdir()
    filenames = []
    for mesh in iterable1:
        outputfilename = os.path.join(dir1, '%s.stl' % next(tempfilenamegen))
        mesh.write(outputfilename)
        filenames.append(outputfilename)
    #absolute path causes error. We rely that the scad file will be in the dame tmpdir
    meshimports = ' '.join("import(file = \"%s\");" % \
        #filename \
        os.path.split(filename)[1] for filename in filenames)
    result = callopenscadmeshstring('%s(){%s}' % (opname,meshimports))
    for filename in filenames:
        try:
            os.unlink(filename)
        except OSError:
            pass
    return result


def meshoponobjs(opname, inobjs):
    """
    takes a string (operation name) and a list of Feature Objects
    returns a mesh and a list of objects that were used
    Part Objects will be meshed
     """
    objs = []
    meshes = []
    for obj in inobjs:
        if obj.isDerivedFrom('Mesh::Feature'):
            objs.append(obj)
            meshes.append(obj.Mesh)
        elif obj.isDerivedFrom('Part::Feature'):
            #mesh the shape
            params = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Mod/OpenSCAD")
            objs.append(obj)
            if False: # disabled due to issue 1292
                meshes.append(MeshPart.meshFromShape(obj.Shape,params.GetFloat(\
                'meshmaxlength',1.0), params.GetFloat('meshmaxarea',0.0),\
                 params.GetFloat('meshlocallen',0.0),\
                 params.GetFloat('meshdeflection',0.0)))
            else:
                meshes.append(Mesh.Mesh(obj.Shape.tessellate(params.GetFloat(\
                            'meshmaxlength',1.0))))
        else:
            pass #neither a mesh nor a part
    if len(objs) > 0:
        return (meshoptempfile(opname,meshes),objs)
    else:
        return (None,[])


def process2D_ObjectsViaOpenSCADShape(ObjList, Operation, doc):
    # https://www.freecad.org/tracker/view.php?id=3419
    params = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Mod/OpenSCAD")
    fn  = params.GetInt('fnForImport',32)
    fnStr = ",$fn=" + str(fn)
    #
    dir1 = tempfile.gettempdir()
    filenames = []
    for item in ObjList :
        outputfilename=os.path.join(dir1,'%s.dxf' % next(tempfilenamegen))
        importDXF.export([item],outputfilename, True, True)
        filenames.append(outputfilename)
    # https://www.freecad.org/tracker/view.php?id=3419
    dxfimports = ' '.join("import(file = \"%s\" %s);" % \
        #filename \
        (os.path.split(filename)[1], fnStr) for filename in filenames)
    #
    tmpfilename = callopenscadstring('%s(){%s}' % (Operation,dxfimports),'dxf')
    from OpenSCAD2Dgeom import importDXFface
    # TBD: assure the given doc is active
    face = importDXFface(tmpfilename,None,None)
    #clean up
    filenames.append(tmpfilename) #delete the output file as well
    try:
        os.unlink(tmpfilename)
    except OSError:
        pass
    return face


def process2D_ObjectsViaOpenSCAD(ObjList, Operation, doc=None):
    doc = doc or FreeCAD.activeDocument()
    face=process2D_ObjectsViaOpenSCADShape(ObjList,Operation,doc)
    obj=doc.addObject('Part::Feature',Operation)
    obj.Shape=face
    # Hide Children
    if FreeCAD.GuiUp:
        for index in ObjList :
            index.ViewObject.hide()
    return obj


def process3D_ObjectsViaOpenSCADShape(ObjList, Operation, maxmeshpoints=None):
    params = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Mod/OpenSCAD")
    if False: # disabled due to issue 1292
        meshes = [MeshPart.meshFromShape(obj.Shape,params.GetFloat(\
                'meshmaxlength',1.0), params.GetFloat('meshmaxarea',0.0),\
                 params.GetFloat('meshlocallen',0.0),\
                 params.GetFloat('meshdeflection',0.0)) for obj in ObjList]
    else:
        meshes = [Mesh.Mesh(obj.Shape.tessellate(params.GetFloat(\
                            'meshmaxlength',1.0))) for obj in ObjList]
    if max(mesh.CountPoints for mesh in meshes) < \
            (maxmeshpoints or params.GetInt('tempmeshmaxpoints', 5000)):
        stlmesh = meshoptempfile(Operation,meshes)
        sh = Part.Shape()
        sh.makeShapeFromMesh(stlmesh.Topology, 0.1)
        solid = Part.Solid(sh)
        solid = solid.removeSplitter()
        if solid.Volume < 0:
            solid.complement()
        return solid


def process3D_ObjectsViaOpenSCAD(doc,ObjList, Operation):
    solid = process3D_ObjectsViaOpenSCADShape(ObjList,Operation)
    if solid is not None:
        obj = doc.addObject('Part::Feature',Operation) #non-parametric object
        obj.Shape=solid#.removeSplitter()
        if FreeCAD.GuiUp:
            for index in ObjList:
                index.ViewObject.hide()
        return obj


def process_ObjectsViaOpenSCADShape(doc, children, name, maxmeshpoints=None):
    if all((not obj.Shape.isNull() and obj.Shape.Volume == 0) \
            for obj in children):
        return process2D_ObjectsViaOpenSCADShape(children,name,doc)
    elif all((not obj.Shape.isNull() and obj.Shape.Volume > 0) \
            for obj in children):
        return process3D_ObjectsViaOpenSCADShape(children,name,maxmeshpoints)
    else:
        FreeCAD.Console.PrintError( translate('OpenSCAD',\
            "OpenSCAD file contains both 2D and 3D shapes. That is not supported in this importer, all shapes must have the same dimensionality.")+'\n')

def process_ObjectsViaOpenSCAD(doc,children,name):
    if all((not obj.Shape.isNull() and obj.Shape.Volume == 0) \
            for obj in children):
        return process2D_ObjectsViaOpenSCAD(children,name,doc)
    elif all((not obj.Shape.isNull() and obj.Shape.Volume > 0) \
            for obj in children):
        return process3D_ObjectsViaOpenSCAD(doc,children,name)
    else:
        FreeCAD.Console.PrintError( translate('OpenSCAD',\
            "Error: either all shapes must be 2D or all shapes must be 3D") + '\n')


def removesubtree(objs):
    def addsubobjs(obj, toremoveset):
        toremove.add(obj)
        for subobj in obj.OutList:
            addsubobjs(subobj, toremoveset)

    toremove = set()
    for obj in objs:
        addsubobjs(obj, toremove)
    checkinlistcomplete = False
    while not checkinlistcomplete:
        for obj in toremove:
            if (obj not in objs) and (frozenset(obj.InList) - toremove):
                toremove.remove(obj)
                break
        else:
            checkinlistcomplete = True
    for obj in toremove:
        obj.Document.removeObject(obj.Name)


def applyPlacement(shape):
    if shape.Placement.isNull():
        return shape
    else:
        if shape.ShapeType == 'Solid':
            return Part.Solid(shape.childShapes()[0])
        elif shape.ShapeType == 'Face':
            return Part.Face(shape.childShapes())
        elif shape.ShapeType == 'Compound':
            return Part.Compound(shape.childShapes())
        elif shape.ShapeType == 'Wire':
            return Part.Wire(shape.childShapes())
        elif shape.ShapeType == 'Shell':
            return Part.Shell(shape.childShapes())
        else:
            return Part.Compound([shape])