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# -*- coding: utf-8 -*-

# Copyright (c) 2020 Simone Bignetti, Gottolengo Italy (simone.b)
#
# This file is part of the FreeCAD CAx development system.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
# USA
#
# You can contact me by mail at simone.bignetti@linux.it

__Name__ = 'HilbertCurve'
__Comment__ = 'This macro creates an Hilbert curve wire in 2 or 3 dimensions with many iterations.'
__Author__  = 'Simone Bignetti'
__Version__ = '1.2.0'
__Date__    = '2020-12-29'
__License__ = 'GNU LESSER GENERAL PUBLIC LICENSE Version 2.1, February 1999'
__Web__ = 'https://wiki.freecad.org/Macro_HilbertCurve'
__Wiki__ = 'https://wiki.freecad.org/Macro_HilbertCurve'
__Icon__ = 'https://wiki.freecad.org/images/6/69/Hilbert_curve_icon.png'
__Help__ = 'Choose the dimensions of the wire, the number of the iterations and the length of the wire segment.'
__Status__ = 'Stable'
__Requires__ = ''
__Communication__ = 'https://forum.freecad.org/viewtopic.php?f=22&t=53781'
__Files__ = 'HilbertCurve.svg'


# For the wire
import FreeCAD as app
import Draft

# For the gui
from PySide import QtGui, QtCore

class HilbertCurve:
    """The class of the Hilbert curve.
    
    By this class it's possible to create a wire
    of a fractal Hilbert curve with
    a fixed number of dimensions and iterations.
    """
    
    def __init__(self, dimensions, iterations):
        """Initialize the Hilbert curve.
        Args:
            iterations (int): iterations to use in constructing the curve
            dimensions (int): number of dimensions
        """

self.dimensions = dimensions
        self.iterations = iterations

# minimum and maximum distance along curve
        self.min_distance = 0
        self.max_distance = 2 ** (self.iterations * self.dimensions) - 1

# minimum and maximum coordinate value in any dimension
        self.min_coordinate = 0
        self.max_coordinate = 2 ** self.iterations - 1

# number of points
        self.number_of_points = 2 ** (self.iterations * self.dimensions)

def point_from_distance(self, distance):
        """Return a point in n-dimensional space given a distance along a the curve.
        Args:
            distance (int): integer distance along the curve
        Returns:
            point (iterable of ints): an n-dimensional vector of length dimensions where
            each component value is between 0 and 2**iterations-1.
        """

bit_string = format(distance, 'b').zfill(self.iterations * self.dimensions)  # zero filled binary distance
        point = [int(bit_string[i::self.dimensions], 2) for i in range(self.dimensions)]  # transpose of distance

# Gray decode: point = point xor (point / 2)
        gray = point[self.dimensions-1] >> 1
        for i in range(self.dimensions-1, 0, -1):
            point[i] ^= point[i-1]
        point[0] ^= gray

# Undo excess work
        q = 2
        while q != (2 << (self.iterations-1)):
            p = q - 1
            for i in range(self.dimensions-1, -1, -1):
                if point[i] & q:
                    # invert
                    point[0] ^= p
                else:
                    # exchange
                    gray = (point[0] ^ point[i]) & p
                    point[0] ^= gray
                    point[i] ^= gray
            q <<= 1

return point

def get_min_distance(self):
        """Return the minimum distance along the curve."""
        return self.min_distance

def get_max_distance(self):
        """Return the maximum distance along the curve."""
        return self.max_distance

def get_min_coordinate(self):
        """Return the minimum coordinate value in any dimension."""
        return self.min_coordinate

def get_max_coordinate(self):
        """Return the maximum coordinate value in any dimension."""
        return self.max_coordinate

def get_number_of_points(self):
        """Return the number of points in the curve."""
        return self.number_of_points

def get_points(self):
        """Return the list of points in the curve."""
        points = []
        for point_number in range(self.number_of_points):
            points.append(self.point_from_distance(point_number))
        return points

def __str__(self):
        return f"HilbertCurve(dimensions={self.dimensions}, iterations={self.iterations})"

def __repr__(self):
        return self.__str__()


class Hilbert_Dialog(QtGui.QDialog):
    """The dialog for the Hilbert curve
    
    This class opens in FreeCAD a dialog to input
    the number of dimensions and the number of iterations
    to create the Hilbert curve.
    OK creates the curve.
    CANCEL quit the macro.
    """

def __init__(self):
        super(Hilbert_Dialog, self).__init__()
        self.setupUi()

def setupUi(self):
        self.dimensions = 2
        self.iterations = 3

self.setGeometry(250, 250, 400, 300)  # Window definition
        self.setWindowTitle("Hilbert curve Macro")

titleLabel = QtGui.QLabel("Create an Hilbert curve in two or three dimensions")  # Title and subtitle
        titleFont = QtGui.QFont()
        titleFont.setBold(True)
        titleFont.setWeight(75)
        titleLabel.setFont(titleFont)
        subtitleLabel = QtGui.QLabel("This macro creates a wire in the draft workbench\nwith the shape of an Hilbert curve in two or three dimensions.\nFor example, you can use this wire as a sweep path.\nIt's recommended to apply a radius at the wire,\nin order to obtain a correct sweep generation.")
        titleBox = QtGui.QVBoxLayout()
        titleBox.addWidget(titleLabel)
        titleBox.addWidget(subtitleLabel)
        titleBox.insertStretch(-1)

dimensionsLabel = QtGui.QLabel("Number of dimensions: ")  # Number of dimensions
        self.twoDradioButton = QtGui.QRadioButton()
        self.twoDradioButton.setText("2D")
        self.twoDradioButton.setChecked(True)
        self.threeDradioButton = QtGui.QRadioButton()
        self.threeDradioButton.setText("3D")
        dimensionsBox=QtGui.QHBoxLayout()
        dimensionsBox.addWidget(dimensionsLabel)
        dimensionsBox.addWidget(self.twoDradioButton)
        dimensionsBox.addWidget(self.threeDradioButton)

iterationsLabel = QtGui.QLabel("Iterations:")  # Iterations  and length spins in a grid
        self.iterationsSpin = QtGui.QSpinBox()
        self.iterationsSpin.setMinimum(1)
        self.iterationsSpin.setMaximum(10)
        lengthLabel = QtGui.QLabel("Length:")
        self.lengthSpin = QtGui.QDoubleSpinBox()
        self.lengthSpin.setMinimum(1.0)
        self.lengthSpin.setMaximum(999999.000000000000000)
        self.lengthSpin.setValue(10.000000000000000)
        grid = QtGui.QGridLayout()
        grid.setSpacing(10)
        grid.addWidget(iterationsLabel, 1, 0)
        grid.addWidget(self.iterationsSpin, 1, 1)
        grid.addWidget(lengthLabel, 2, 0)
        grid.addWidget(self.lengthSpin, 2, 1)

okButton = QtGui.QPushButton("OK")  # Ok and Cancel Buttons at right bottom
        okButton.clicked.connect(self.onOkButton)
        cancelButton = QtGui.QPushButton("Cancel")
        cancelButton.clicked.connect(self.onCancelButton)
        buttonBox = QtGui.QHBoxLayout()
        buttonBox.addStretch()
        buttonBox.addWidget(okButton)
        buttonBox.addWidget(cancelButton)

vbox = QtGui.QVBoxLayout()
        vbox.addLayout(titleBox)
        vbox.addLayout(dimensionsBox)
        vbox.addLayout(grid)
        vbox.addLayout(buttonBox)
        vbox.setSpacing(30)
        vbox.insertStretch(1)
        self.setLayout(vbox)

self.show()

def onOkButton(self):
        if self.twoDradioButton.isChecked():
            dimensions = 2
        else:
            dimensions = 3
        iterations = self.iterationsSpin.value()
        length = self.lengthSpin.value()
        HC=HilbertCurve(dimensions, iterations)
        points = HC.get_points()
        pl = app.Placement()
        pl.Rotation.Q = (0.0, 0.0, 0.0, 1.0)
        pl.Base = app.Vector(0.0, 0.0, 0.0)
        vectors = []
        if dimensions == 2:
            for point in points:
                vectors.append(app.Vector(point[0]*length, point[1]*length, 0.0))
        else:
            for point in points:
                vectors.append(app.Vector(point[0]*length, point[1]*length, point[2]*length))
        wire = Draft.makeWire(vectors, placement=pl, closed=False, face=False, support=None)
        wire.Label = "Hilbert"
        Draft.autogroup(wire)
        self.close()

def onCancelButton(self):
        self.close()


hilbert_dialog = Hilbert_Dialog()
hilbert_dialog.exec()