# Source code for pymatgen.vis.structure_vtk

    # coding: utf-8
    # Copyright (c) Pymatgen Development Team.
    # Distributed under the terms of the MIT License.

    """
    This module contains classes to wrap Python VTK to make nice molecular plots.
    """

    __author__ = "Shyue Ping Ong"
    __copyright__ = "Copyright 2011, The Materials Project"
    __version__ = "0.1"
    __maintainer__ = "Shyue Ping Ong"
    __email__ = "shyuep@gmail.com"
    __date__ = "Nov 27, 2011"

    import os
    import itertools
    import math
    import subprocess
    import time

    import numpy as np

    try:
        import vtk
        from vtk import vtkInteractorStyleTrackballCamera
    except ImportError:
        # VTK not present. The Camera is to set object to avoid errors in unittest.
        vtk = None
        vtkInteractorStyleTrackballCamera = object

    from monty.serialization import loadfn
    from monty.dev import requires

    from pymatgen.util.coord import in_coord_list
    from pymatgen.core.periodic_table import Specie
    from pymatgen.core.structure import Structure
    from pymatgen.core.sites import PeriodicSite

    module_dir = os.path.dirname(os.path.abspath(__file__))
    EL_COLORS = loadfn(os.path.join(module_dir, "ElementColorSchemes.yaml"))

    class StructureVis:
        """
        Provides Structure object visualization using VTK.
        """

        @requires(vtk, "Visualization requires the installation of VTK with "
                       "Python bindings.")
        def __init__(self, element_color_mapping=None, show_unit_cell=True,
                     show_bonds=False, show_polyhedron=True,
                     poly_radii_tol_factor=0.5, excluded_bonding_elements=None):
            """
            Constructs a Structure Visualization.

            Args:
                element_color_mapping: Optional color mapping for the elements,
                    as a dict of {symbol: rgb tuple}. For example, {"Fe": (255,
                    123,0), ....} If None is specified, a default based on
                    Jmol"s color scheme is used.
                show_unit_cell: Set to False to not show the unit cell
                    boundaries. Defaults to True.
                show_bonds: Set to True to show bonds. Defaults to True.
                show_polyhedron: Set to True to show polyhedrons. Defaults to
                    False.
                poly_radii_tol_factor: The polyhedron and bonding code uses the
                    ionic radii of the elements or species to determine if two
                    atoms are bonded. This specifies a tolerance scaling factor
                    such that atoms which are (1 + poly_radii_tol_factor) * sum
                    of ionic radii apart are still considered as bonded.
                excluded_bonding_elements: List of atom types to exclude from
                    bonding determination. Defaults to an empty list. Useful
                    when trying to visualize a certain atom type in the
                    framework (e.g., Li in a Li-ion battery cathode material).

            Useful keyboard shortcuts implemented.
                h : Show help
                A/a : Increase/decrease cell by one unit vector in a-direction
                B/b : Increase/decrease cell by one unit vector in b-direction
                C/c : Increase/decrease cell by one unit vector in c-direction
                # : Toggle showing of polyhedrons
                - : Toggle showing of bonds
                [ : Decrease poly_radii_tol_factor by 0.05
                ] : Increase poly_radii_tol_factor by 0.05
                r : Reset camera direction
                o : Orthogonalize structure
                Up/Down : Rotate view along Up direction by 90 clock/anticlockwise
                Left/right : Rotate view along camera direction by 90
                clock/anticlockwise
            """
            # create a rendering window and renderer
            self.ren = vtk.vtkRenderer()
            self.ren_win = vtk.vtkRenderWindow()
            self.ren_win.AddRenderer(self.ren)
            self.ren.SetBackground(1, 1, 1)
            self.title = "Structure Visualizer"
            # create a renderwindowinteractor
            self.iren = vtk.vtkRenderWindowInteractor()
            self.iren.SetRenderWindow(self.ren_win)
            self.mapper_map = {}
            self.structure = None

            if element_color_mapping:
                self.el_color_mapping = element_color_mapping
            else:
                self.el_color_mapping = EL_COLORS["VESTA"]
            self.show_unit_cell = show_unit_cell
            self.show_bonds = show_bonds
            self.show_polyhedron = show_polyhedron
            self.poly_radii_tol_factor = poly_radii_tol_factor
            self.excluded_bonding_elements = excluded_bonding_elements if \
                excluded_bonding_elements else []
            self.show_help = True
            self.supercell = [[1, 0, 0], [0, 1, 0], [0, 0, 1]]
            self.redraw()

            style = StructureInteractorStyle(self)
            self.iren.SetInteractorStyle(style)
            self.ren.parent = self

        def rotate_view(self, axis_ind=0, angle=0):
            """
            Rotate the camera view.

            Args:
                axis_ind: Index of axis to rotate. Defaults to 0, i.e., a-axis.
                angle: Angle to rotate by. Defaults to 0.
            """
            camera = self.ren.GetActiveCamera()
            if axis_ind == 0:
                camera.Roll(angle)
            elif axis_ind == 1:
                camera.Azimuth(angle)
            else:
                camera.Pitch(angle)
            self.ren_win.Render()

        def write_image(self, filename="image.png", magnification=1,
                        image_format="png"):
            """
            Save render window to an image.

            Arguments:
                filename:
                    filename to save to. Defaults to image.png.
                magnification:
                    magnification. Use it to render high res images.
                image_format:
                    choose between jpeg, png.  Png is the default.
            """
            render_large = vtk.vtkRenderLargeImage()
            render_large.SetInput(self.ren)
            if image_format == "jpeg":
                writer = vtk.vtkJPEGWriter()
                writer.SetQuality(80)
            else:
                writer = vtk.vtkPNGWriter()

            render_large.SetMagnification(magnification)
            writer.SetFileName(filename)

            writer.SetInputConnection(render_large.GetOutputPort())
            self.ren_win.Render()
            writer.Write()
            del render_large

        def redraw(self, reset_camera=False):
            """
            Redraw the render window.

            Args:
                reset_camera: Set to True to reset the camera to a
                    pre-determined default for each structure.  Defaults to False.
            """
            self.ren.RemoveAllViewProps()
            self.picker = None
            self.add_picker_fixed()
            self.helptxt_mapper = vtk.vtkTextMapper()
            tprops = self.helptxt_mapper.GetTextProperty()
            tprops.SetFontSize(14)
            tprops.SetFontFamilyToTimes()
            tprops.SetColor(0, 0, 0)

            if self.structure is not None:
                self.set_structure(self.structure, reset_camera)

            self.ren_win.Render()

        def orthongonalize_structure(self):
            """
            Orthogonalize the structure.
            """
            if self.structure is not None:
                self.set_structure(self.structure.copy(sanitize=True))
            self.ren_win.Render()

        def display_help(self):
            """
            Display the help for various keyboard shortcuts.
            """
            helptxt = ["h : Toggle help",
                       "A/a, B/b or C/c : Increase/decrease cell by one a,"
                       " b or c unit vector", "# : Toggle showing of polyhedrons",
                       "-: Toggle showing of bonds", "r : Reset camera direction",
                       "[/]: Decrease or increase poly_radii_tol_factor "
                       "by 0.05. Value = " + str(self.poly_radii_tol_factor),
                       "Up/Down: Rotate view along Up direction by 90 "
                       "clockwise/anticlockwise",
                       "Left/right: Rotate view along camera direction by "
                       "90 clockwise/anticlockwise", "s: Save view to image.png",
                       "o: Orthogonalize structure"]
            self.helptxt_mapper.SetInput("\n".join(helptxt))
            self.helptxt_actor.SetPosition(10, 10)
            self.helptxt_actor.VisibilityOn()

        def set_structure(self, structure, reset_camera=True, to_unit_cell=True):
            """
            Add a structure to the visualizer.

            Args:
                structure: structure to visualize
                reset_camera: Set to True to reset the camera to a default
                    determined based on the structure.
                to_unit_cell: Whether or not to fall back sites into the unit cell.
            """
            self.ren.RemoveAllViewProps()

            has_lattice = hasattr(structure, "lattice")

            if has_lattice:
                s = Structure.from_sites(structure, to_unit_cell=to_unit_cell)
                s.make_supercell(self.supercell, to_unit_cell=to_unit_cell)
            else:
                s = structure

            inc_coords = []
            for site in s:
                self.add_site(site)
                inc_coords.append(site.coords)

            count = 0
            labels = ["a", "b", "c"]
            colors = [(1, 0, 0), (0, 1, 0), (0, 0, 1)]

            if has_lattice:
                matrix = s.lattice.matrix

            if self.show_unit_cell and has_lattice:
                # matrix = s.lattice.matrix
                self.add_text([0, 0, 0], "o")
                for vec in matrix:
                    self.add_line((0, 0, 0), vec, colors[count])
                    self.add_text(vec, labels[count], colors[count])
                    count += 1
                for (vec1, vec2) in itertools.permutations(matrix, 2):
                    self.add_line(vec1, vec1 + vec2)
                for (vec1, vec2, vec3) in itertools.permutations(matrix, 3):
                    self.add_line(vec1 + vec2, vec1 + vec2 + vec3)

            if self.show_bonds or self.show_polyhedron:
                elements = sorted(s.composition.elements, key=lambda a: a.X)
                anion = elements[-1]

                def contains_anion(site):
                    for sp in site.species.keys():
                        if sp.symbol == anion.symbol:
                            return True
                    return False

                anion_radius = anion.average_ionic_radius
                for site in s:
                    exclude = False
                    max_radius = 0
                    color = np.array([0, 0, 0])
                    for sp, occu in site.species.items():
                        if sp.symbol in self.excluded_bonding_elements or sp == anion:
                            exclude = True
                            break
                        max_radius = max(max_radius, sp.average_ionic_radius)
                        color = color + occu * np.array(self.el_color_mapping.get(sp.symbol, [0, 0, 0]))

                    if not exclude:
                        max_radius = (1 + self.poly_radii_tol_factor) * (max_radius + anion_radius)
                        nn = structure.get_neighbors(site, float(max_radius))
                        nn_sites = []
                        for neighbor in nn:
                            if contains_anion(neighbor):
                                nn_sites.append(neighbor)
                                if not in_coord_list(inc_coords, neighbor.coords):
                                    self.add_site(neighbor)
                        if self.show_bonds:
                            self.add_bonds(nn_sites, site)
                        if self.show_polyhedron:
                            color = [i / 255 for i in color]
                            self.add_polyhedron(nn_sites, site, color)

            if self.show_help:
                self.helptxt_actor = vtk.vtkActor2D()
                self.helptxt_actor.VisibilityOn()
                self.helptxt_actor.SetMapper(self.helptxt_mapper)
                self.ren.AddActor(self.helptxt_actor)
                self.display_help()

            camera = self.ren.GetActiveCamera()
            if reset_camera:
                if has_lattice:
                    # Adjust the camera for best viewing
                    lengths = s.lattice.abc
                    pos = (matrix[1] + matrix[2]) * 0.5 + matrix[0] * max(lengths) / lengths[0] * 3.5
                    camera.SetPosition(pos)
                    camera.SetViewUp(matrix[2])
                    camera.SetFocalPoint((matrix[0] + matrix[1] + matrix[2]) * 0.5)
                else:
                    origin = s.center_of_mass
                    max_site = max(
                        s, key=lambda site: site.distance_from_point(origin))
                    camera.SetPosition(origin + 5 * (max_site.coords - origin))
                    camera.SetFocalPoint(s.center_of_mass)

            self.structure = structure
            self.title = s.composition.formula

        def zoom(self, factor):
            """
            Zoom the camera view by a factor.
            """
            camera = self.ren.GetActiveCamera()
            camera.Zoom(factor)
            self.ren_win.Render()

        def show(self):
            """
            Display the visualizer.
            """
            self.iren.Initialize()
            self.ren_win.SetSize(800, 800)
            self.ren_win.SetWindowName(self.title)
            self.ren_win.Render()
            self.iren.Start()

        def add_site(self, site):
            """
            Add a site to the render window. The site is displayed as a sphere, the
            color of which is determined based on the element. Partially occupied
            sites are displayed as a single element color, though the site info
            still shows the partial occupancy.

            Args:
                site: Site to add.
            """
            start_angle = 0
            radius = 0
            total_occu = 0

            for specie, occu in site.species.items():
                radius += occu * (specie.ionic_radius
                                  if isinstance(specie, Specie) and specie.ionic_radius
                                  else specie.average_ionic_radius)
                total_occu += occu

            vis_radius = 0.2 + 0.002 * radius

            for specie, occu in site.species.items():
                if not specie:
                    color = (1, 1, 1)
                elif specie.symbol in self.el_color_mapping:
                    color = [i / 255 for i in self.el_color_mapping[specie.symbol]]
                mapper = self.add_partial_sphere(site.coords, vis_radius, color,
                                                 start_angle, start_angle + 360 * occu)
                self.mapper_map[mapper] = [site]
                start_angle += 360 * occu

            if total_occu < 1:
                mapper = self.add_partial_sphere(site.coords, vis_radius, (1, 1, 1),
                                                 start_angle, start_angle + 360 * (1 - total_occu))
                self.mapper_map[mapper] = [site]

        def add_partial_sphere(self, coords, radius, color, start=0, end=360,
                               opacity=1.0):
            """
            Adding a partial sphere (to display partial occupancies.

            Args:
                coords (nd.array): Coordinates
                radius (float): Radius of sphere
                color (): Color of sphere.
                start (float): Starting angle.
                end (float): Ending angle.
                opacity (float): Opacity.
            """
            sphere = vtk.vtkSphereSource()
            sphere.SetCenter(coords)
            sphere.SetRadius(radius)
            sphere.SetThetaResolution(18)
            sphere.SetPhiResolution(18)
            sphere.SetStartTheta(start)
            sphere.SetEndTheta(end)

            mapper = vtk.vtkPolyDataMapper()
            mapper.SetInputConnection(sphere.GetOutputPort())
            actor = vtk.vtkActor()
            actor.SetMapper(mapper)
            actor.GetProperty().SetColor(color)
            actor.GetProperty().SetOpacity(opacity)
            self.ren.AddActor(actor)
            return mapper

        def add_text(self, coords, text, color=(0, 0, 0)):
            """
            Add text at a coordinate.

            Args:
                coords: Coordinates to add text at.
                text: Text to place.
                color: Color for text as RGB. Defaults to black.
            """
            source = vtk.vtkVectorText()
            source.SetText(text)
            mapper = vtk.vtkPolyDataMapper()
            mapper.SetInputConnection(source.GetOutputPort())
            follower = vtk.vtkFollower()
            follower.SetMapper(mapper)
            follower.GetProperty().SetColor(color)
            follower.SetPosition(coords)
            follower.SetScale(0.5)
            self.ren.AddActor(follower)
            follower.SetCamera(self.ren.GetActiveCamera())

        def add_line(self, start, end, color=(0.5, 0.5, 0.5), width=1):
            """
            Adds a line.

            Args:
                start: Starting coordinates for line.
                end: Ending coordinates for line.
                color: Color for text as RGB. Defaults to grey.
                width: Width of line. Defaults to 1.
            """
            source = vtk.vtkLineSource()
            source.SetPoint1(start)
            source.SetPoint2(end)

            vertexIDs = vtk.vtkStringArray()
            vertexIDs.SetNumberOfComponents(1)
            vertexIDs.SetName("VertexIDs")
            # Set the vertex labels
            vertexIDs.InsertNextValue("a")
            vertexIDs.InsertNextValue("b")
            source.GetOutput().GetPointData().AddArray(vertexIDs)

            mapper = vtk.vtkPolyDataMapper()
            mapper.SetInputConnection(source.GetOutputPort())
            actor = vtk.vtkActor()
            actor.SetMapper(mapper)
            actor.GetProperty().SetColor(color)
            actor.GetProperty().SetLineWidth(width)
            self.ren.AddActor(actor)

        def add_polyhedron(self, neighbors, center, color, opacity=1.0,
                           draw_edges=False, edges_color=[0.0, 0.0, 0.0],
                           edges_linewidth=2):
            """
            Adds a polyhedron.

            Args:
                neighbors: Neighbors of the polyhedron (the vertices).
                center: The atom in the center of the polyhedron.
                color: Color for text as RGB.
                opacity: Opacity of the polyhedron
                draw_edges: If set to True, the a line will be drawn at each edge
                edges_color: Color of the line for the edges
                edges_linewidth: Width of the line drawn for the edges
            """
            points = vtk.vtkPoints()
            conv = vtk.vtkConvexPointSet()
            for i in range(len(neighbors)):
                x, y, z = neighbors[i].coords
                points.InsertPoint(i, x, y, z)
                conv.GetPointIds().InsertId(i, i)
            grid = vtk.vtkUnstructuredGrid()
            grid.Allocate(1, 1)
            grid.InsertNextCell(conv.GetCellType(), conv.GetPointIds())
            grid.SetPoints(points)

            dsm = vtk.vtkDataSetMapper()
            polysites = [center]
            polysites.extend(neighbors)
            self.mapper_map[dsm] = polysites
            if vtk.VTK_MAJOR_VERSION <= 5:
                dsm.SetInputConnection(grid.GetProducerPort())
            else:
                dsm.SetInputData(grid)
            ac = vtk.vtkActor()
            # ac.SetMapper(mapHull)
            ac.SetMapper(dsm)
            ac.GetProperty().SetOpacity(opacity)
            if color == 'element':
                # If partial occupations are involved, the color of the specie with
                # the highest occupation is used
                myoccu = 0.0
                for specie, occu in center.species.items():
                    if occu > myoccu:
                        myspecie = specie
                        myoccu = occu
                color = [i / 255 for i in self.el_color_mapping[myspecie.symbol]]
                ac.GetProperty().SetColor(color)
            else:
                ac.GetProperty().SetColor(color)
            if draw_edges:
                ac.GetProperty().SetEdgeColor(edges_color)
                ac.GetProperty().SetLineWidth(edges_linewidth)
                ac.GetProperty().EdgeVisibilityOn()
            self.ren.AddActor(ac)

        def add_triangle(self, neighbors, color, center=None, opacity=0.4,
                         draw_edges=False, edges_color=[0.0, 0.0, 0.0],
                         edges_linewidth=2):
            """
            Adds a triangular surface between three atoms.

            Args:
                atoms: Atoms between which a triangle will be drawn.
                color: Color for triangle as RGB.
                center: The "central atom" of the triangle
                opacity: opacity of the triangle
                draw_edges: If set to True, the a line will be  drawn at each edge
                edges_color: Color of the line for the edges
                edges_linewidth: Width of the line drawn for the edges
            """
            points = vtk.vtkPoints()
            triangle = vtk.vtkTriangle()
            for ii in range(3):
                points.InsertNextPoint(neighbors[ii].x, neighbors[ii].y,
                                       neighbors[ii].z)
                triangle.GetPointIds().SetId(ii, ii)
            triangles = vtk.vtkCellArray()
            triangles.InsertNextCell(triangle)

            # polydata object
            trianglePolyData = vtk.vtkPolyData()
            trianglePolyData.SetPoints(points)
            trianglePolyData.SetPolys(triangles)

            # mapper
            mapper = vtk.vtkPolyDataMapper()
            mapper.SetInput(trianglePolyData)

            ac = vtk.vtkActor()
            ac.SetMapper(mapper)
            ac.GetProperty().SetOpacity(opacity)
            if color == 'element':
                if center is None:
                    raise ValueError(
                        'Color should be chosen according to the central atom, '
                        'and central atom is not provided')
                # If partial occupations are involved, the color of the specie with
                # the highest occupation is used
                myoccu = 0.0
                for specie, occu in center.species.items():
                    if occu > myoccu:
                        myspecie = specie
                        myoccu = occu
                color = [i / 255 for i in self.el_color_mapping[myspecie.symbol]]
                ac.GetProperty().SetColor(color)
            else:
                ac.GetProperty().SetColor(color)
            if draw_edges:
                ac.GetProperty().SetEdgeColor(edges_color)
                ac.GetProperty().SetLineWidth(edges_linewidth)
                ac.GetProperty().EdgeVisibilityOn()
            self.ren.AddActor(ac)

        def add_faces(self, faces, color, opacity=0.35):
            """
            Adding face of polygon.

            Args:
                faces (): Coordinates of the faces.
                color (): Color.
                opacity (float): Opacity
            """
            for face in faces:
                if len(face) == 3:
                    points = vtk.vtkPoints()
                    triangle = vtk.vtkTriangle()
                    for ii in range(3):
                        points.InsertNextPoint(face[ii][0], face[ii][1], face[ii][2])
                        triangle.GetPointIds().SetId(ii, ii)
                    triangles = vtk.vtkCellArray()
                    triangles.InsertNextCell(triangle)
                    trianglePolyData = vtk.vtkPolyData()
                    trianglePolyData.SetPoints(points)
                    trianglePolyData.SetPolys(triangles)
                    mapper = vtk.vtkPolyDataMapper()
                    if vtk.VTK_MAJOR_VERSION <= 5:
                        mapper.SetInputConnection(trianglePolyData.GetProducerPort())
                    else:
                        mapper.SetInputData(trianglePolyData)
                    # mapper.SetInput(trianglePolyData)
                    ac = vtk.vtkActor()
                    ac.SetMapper(mapper)
                    ac.GetProperty().SetOpacity(opacity)
                    ac.GetProperty().SetColor(color)
                    self.ren.AddActor(ac)
                elif False and len(face) == 4:
                    points = vtk.vtkPoints()
                    for ii in range(4):
                        points.InsertNextPoint(face[ii][0], face[ii][1], face[ii][2])
                    line1 = vtk.vtkLine()
                    line1.GetPointIds().SetId(0, 0)
                    line1.GetPointIds().SetId(1, 2)
                    line2 = vtk.vtkLine()
                    line2.GetPointIds().SetId(0, 3)
                    line2.GetPointIds().SetId(1, 1)
                    lines = vtk.vtkCellArray()
                    lines.InsertNextCell(line1)
                    lines.InsertNextCell(line2)
                    polydata = vtk.vtkPolyData()
                    polydata.SetPoints(points)
                    polydata.SetLines(lines)
                    ruledSurfaceFilter = vtk.vtkRuledSurfaceFilter()
                    ruledSurfaceFilter.SetInput(polydata)
                    ruledSurfaceFilter.SetResolution(15, 15)
                    ruledSurfaceFilter.SetRuledModeToResample()
                    mapper = vtk.vtkPolyDataMapper()
                    mapper.SetInput(ruledSurfaceFilter.GetOutput())
                    ac = vtk.vtkActor()
                    ac.SetMapper(mapper)
                    ac.GetProperty().SetOpacity(opacity)
                    ac.GetProperty().SetColor(color)
                    self.ren.AddActor(ac)
                elif len(face) > 3:
                    center = np.zeros(3, np.float)
                    for site in face:
                        center += site
                    center /= np.float(len(face))
                    for ii in range(len(face)):
                        points = vtk.vtkPoints()
                        triangle = vtk.vtkTriangle()
                        points.InsertNextPoint(face[ii][0], face[ii][1], face[ii][2])
                        ii2 = np.mod(ii + 1, len(face))
                        points.InsertNextPoint(face[ii2][0], face[ii2][1], face[ii2][2])
                        points.InsertNextPoint(center[0], center[1], center[2])
                        for ii in range(3):
                            triangle.GetPointIds().SetId(ii, ii)
                        triangles = vtk.vtkCellArray()
                        triangles.InsertNextCell(triangle)
                        trianglePolyData = vtk.vtkPolyData()
                        trianglePolyData.SetPoints(points)
                        trianglePolyData.SetPolys(triangles)
                        mapper = vtk.vtkPolyDataMapper()
                        if vtk.VTK_MAJOR_VERSION <= 5:
                            mapper.SetInputConnection(trianglePolyData.GetProducerPort())
                        else:
                            mapper.SetInputData(trianglePolyData)
                        # mapper.SetInput(trianglePolyData)
                        ac = vtk.vtkActor()
                        ac.SetMapper(mapper)
                        ac.GetProperty().SetOpacity(opacity)
                        ac.GetProperty().SetColor(color)
                        self.ren.AddActor(ac)
                else:
                    raise ValueError("Number of points for a face should be >= 3")

        def add_edges(self, edges, type='line', linewidth=2, color=[0.0, 0.0, 0.0]):
            """
            Args:
                edges (): List of edges
                type ():
                linewidth (): Width of line
                color (nd.array/tuple): RGB color.
            """
            points = vtk.vtkPoints()
            lines = vtk.vtkCellArray()
            for iedge, edge in enumerate(edges):
                points.InsertPoint(2 * iedge, edge[0])
                points.InsertPoint(2 * iedge + 1, edge[1])
                lines.InsertNextCell(2)
                lines.InsertCellPoint(2 * iedge)
                lines.InsertCellPoint(2 * iedge + 1)
            polydata = vtk.vtkPolyData()
            polydata.SetPoints(points)
            polydata.SetLines(lines)
            mapper = vtk.vtkPolyDataMapper()
            if vtk.VTK_MAJOR_VERSION <= 5:
                mapper.SetInputConnection(polydata.GetProducerPort())
            else:
                mapper.SetInputData(polydata)
            # mapper.SetInput(polydata)
            ac = vtk.vtkActor()
            ac.SetMapper(mapper)
            ac.GetProperty().SetColor(color)
            ac.GetProperty().SetLineWidth(linewidth)
            self.ren.AddActor(ac)

        def add_bonds(self, neighbors, center, color=None, opacity=None,
                      radius=0.1):
            """
            Adds bonds for a site.

            Args:
                neighbors: Neighbors of the site.
                center: The site in the center for all bonds.
                color: Color of the tubes representing the bonds
                opacity: Opacity of the tubes representing the bonds
                radius: Radius of tube s representing the bonds
            """
            points = vtk.vtkPoints()
            points.InsertPoint(0, center.x, center.y, center.z)
            n = len(neighbors)
            lines = vtk.vtkCellArray()
            for i in range(n):
                points.InsertPoint(i + 1, neighbors[i].coords)
                lines.InsertNextCell(2)
                lines.InsertCellPoint(0)
                lines.InsertCellPoint(i + 1)
            pd = vtk.vtkPolyData()
            pd.SetPoints(points)
            pd.SetLines(lines)

            tube = vtk.vtkTubeFilter()
            if vtk.VTK_MAJOR_VERSION <= 5:
                tube.SetInputConnection(pd.GetProducerPort())
            else:
                tube.SetInputData(pd)
            tube.SetRadius(radius)

            mapper = vtk.vtkPolyDataMapper()
            mapper.SetInputConnection(tube.GetOutputPort())

            actor = vtk.vtkActor()
            actor.SetMapper(mapper)
            if opacity is not None:
                actor.GetProperty().SetOpacity(opacity)
            if color is not None:
                actor.GetProperty().SetColor(color)
            self.ren.AddActor(actor)

        def add_picker_fixed(self):
            """
            Create a cell picker.Returns:
            """
            picker = vtk.vtkCellPicker()

            # Create a Python function to create the text for the text mapper used
            # to display the results of picking.

            def annotate_pick(obj, event):
                if picker.GetCellId() < 0 and not self.show_help:
                    self.helptxt_actor.VisibilityOff()
                else:
                    mapper = picker.GetMapper()
                    if mapper in self.mapper_map:
                        output = []
                        for site in self.mapper_map[mapper]:
                            row = ["{} - ".format(site.species_string),
                                   ", ".join(["{:.3f}".format(c)
                                              for c in site.frac_coords]),
                                   "[" + ", ".join(["{:.3f}".format(c)
                                                    for c in site.coords]) +
                                   "]"]
                            output.append("".join(row))
                        self.helptxt_mapper.SetInput("\n".join(output))
                        self.helptxt_actor.SetPosition(10, 10)
                        self.helptxt_actor.VisibilityOn()
                        self.show_help = False

            self.picker = picker
            picker.AddObserver("EndPickEvent", annotate_pick)
            self.iren.SetPicker(picker)

        def add_picker(self):
            """
            Create a cell picker.
            """
            picker = vtk.vtkCellPicker()
            # Create a Python function to create the text for the text mapper used
            # to display the results of picking.
            source = vtk.vtkVectorText()
            mapper = vtk.vtkPolyDataMapper()
            mapper.SetInputConnection(source.GetOutputPort())
            follower = vtk.vtkFollower()
            follower.SetMapper(mapper)
            follower.GetProperty().SetColor((0, 0, 0))
            follower.SetScale(0.2)
            self.ren.AddActor(follower)
            follower.SetCamera(self.ren.GetActiveCamera())
            follower.VisibilityOff()

            def annotate_pick(obj, event):
                if picker.GetCellId() < 0:
                    follower.VisibilityOff()
                else:
                    pick_pos = picker.GetPickPosition()
                    mapper = picker.GetMapper()
                    if mapper in self.mapper_map:
                        site = self.mapper_map[mapper]
                        output = [site.species_string, "Frac. coords: " +
                                  " ".join(["{:.4f}".format(c)
                                            for c in
                                            site.frac_coords])]
                        source.SetText("\n".join(output))
                        follower.SetPosition(pick_pos)
                        follower.VisibilityOn()

            picker.AddObserver("EndPickEvent", annotate_pick)
            self.picker = picker
            self.iren.SetPicker(picker)

    class StructureInteractorStyle(vtkInteractorStyleTrackballCamera):
        """
        A custom interactor style for visualizing structures.
        """

        def __init__(self, parent):
            """
            Args:
                parent ():
            """
            self.parent = parent
            self.AddObserver("LeftButtonPressEvent", self.leftButtonPressEvent)
            self.AddObserver("MouseMoveEvent", self.mouseMoveEvent)
            self.AddObserver("LeftButtonReleaseEvent", self.leftButtonReleaseEvent)
            self.AddObserver("KeyPressEvent", self.keyPressEvent)

        def leftButtonPressEvent(self, obj, event):
            """
            Args:
                obj ():
                event ():
            """
            self.mouse_motion = 0
            self.OnLeftButtonDown()
            return

        def mouseMoveEvent(self, obj, event):
            """
            Args:
                obj ():
                event ():
            """
            self.mouse_motion = 1
            self.OnMouseMove()
            return

        def leftButtonReleaseEvent(self, obj, event):
            """
            Args:
                obj ():
                event ():
            """
            ren = obj.GetCurrentRenderer()
            iren = ren.GetRenderWindow().GetInteractor()
            if self.mouse_motion == 0:
                pos = iren.GetEventPosition()
                iren.GetPicker().Pick(pos[0], pos[1], 0, ren)
            self.OnLeftButtonUp()
            return

        def keyPressEvent(self, obj, event):
            """
            Args:
                obj ():
                event ():
            """
            parent = obj.GetCurrentRenderer().parent
            sym = parent.iren.GetKeySym()

            if sym in "ABCabc":
                if sym == "A":
                    parent.supercell[0][0] += 1
                elif sym == "B":
                    parent.supercell[1][1] += 1
                elif sym == "C":
                    parent.supercell[2][2] += 1
                elif sym == "a":
                    parent.supercell[0][0] = max(parent.supercell[0][0] - 1, 1)
                elif sym == "b":
                    parent.supercell[1][1] = max(parent.supercell[1][1] - 1, 1)
                elif sym == "c":
                    parent.supercell[2][2] = max(parent.supercell[2][2] - 1, 1)
                parent.redraw()
            elif sym == "numbersign":
                parent.show_polyhedron = not parent.show_polyhedron
                parent.redraw()
            elif sym == "minus":
                parent.show_bonds = not parent.show_bonds
                parent.redraw()
            elif sym == "bracketleft":
                parent.poly_radii_tol_factor -= 0.05 \
                    if parent.poly_radii_tol_factor > 0 else 0
                parent.redraw()
            elif sym == "bracketright":
                parent.poly_radii_tol_factor += 0.05
                parent.redraw()
            elif sym == "h":
                parent.show_help = not parent.show_help
                parent.redraw()
            elif sym == "r":
                parent.redraw(True)
            elif sym == "s":
                parent.write_image("image.png")
            elif sym == "Up":
                parent.rotate_view(1, 90)
            elif sym == "Down":
                parent.rotate_view(1, -90)
            elif sym == "Left":
                parent.rotate_view(0, -90)
            elif sym == "Right":
                parent.rotate_view(0, 90)
            elif sym == "o":
                parent.orthongonalize_structure()
                parent.redraw()

            self.OnKeyPress()

    def make_movie(structures, output_filename="movie.mp4", zoom=1.0, fps=20,
                   bitrate="10000k", quality=1, **kwargs):
        r"""
        Generate a movie from a sequence of structures using vtk and ffmpeg.

        Args:
            structures ([Structure]): sequence of structures
            output_filename (str): filename for structure output. defaults to
                movie.mp4
            zoom (float): A zoom to be applied to the visualizer. Defaults to 1.0.
            fps (int): Frames per second for the movie. Defaults to 20.
            bitrate (str): Video bitate.  Defaults to "10000k" (fairly high
                quality).
            quality (int): A quality scale. Defaults to 1.
            \\*\\*kwargs: Any kwargs supported by StructureVis to modify the images
                generated.
        """
        vis = StructureVis(**kwargs)
        vis.show_help = False
        vis.redraw()
        vis.zoom(zoom)
        sigfig = int(math.floor(math.log10(len(structures))) + 1)
        filename = "image{0:0" + str(sigfig) + "d}.png"
        for i, s in enumerate(structures):
            vis.set_structure(s)
            vis.write_image(filename.format(i), 3)
        filename = "image%0" + str(sigfig) + "d.png"
        args = ["ffmpeg", "-y", "-i", filename,
                "-q:v", str(quality), "-r", str(fps), "-b:v", str(bitrate),
                output_filename]
        subprocess.Popen(args)

    class MultiStructuresVis(StructureVis):
        """
        Visualization for multiple structures.
        """
        DEFAULT_ANIMATED_MOVIE_OPTIONS = {'time_between_frames': 0.1,
                                          'looping_type': 'restart',
                                          'number_of_loops': 1,
                                          'time_between_loops': 1.0}

        def __init__(self, element_color_mapping=None, show_unit_cell=True,
                     show_bonds=False, show_polyhedron=False,
                     poly_radii_tol_factor=0.5, excluded_bonding_elements=None,
                     animated_movie_options=DEFAULT_ANIMATED_MOVIE_OPTIONS):
            """
            Args:
                element_color_mapping: Optional color mapping for the elements,
                    as a dict of {symbol: rgb tuple}. For example, {"Fe": (255,
                    123,0), ....} If None is specified, a default based on
                    Jmol"s color scheme is used.
                show_unit_cell: Set to False to not show the unit cell
                    boundaries. Defaults to True.
                show_bonds: Set to True to show bonds. Defaults to True.
                show_polyhedron: Set to True to show polyhedrons. Defaults to
                    False.
                poly_radii_tol_factor: The polyhedron and bonding code uses the
                    ionic radii of the elements or species to determine if two
                    atoms are bonded. This specifies a tolerance scaling factor
                    such that atoms which are (1 + poly_radii_tol_factor) * sum
                    of ionic radii apart are still considered as bonded.
                excluded_bonding_elements: List of atom types to exclude from
                    bonding determination. Defaults to an empty list. Useful
                    when trying to visualize a certain atom type in the
                    framework (e.g., Li in a Li-ion battery cathode material).
                animated_movie_options (): Used for moving.
            """
            super().__init__(element_color_mapping=element_color_mapping,
                             show_unit_cell=show_unit_cell,
                             show_bonds=show_bonds, show_polyhedron=show_polyhedron,
                             poly_radii_tol_factor=poly_radii_tol_factor,
                             excluded_bonding_elements=excluded_bonding_elements)
            self.warningtxt_actor = vtk.vtkActor2D()
            self.infotxt_actor = vtk.vtkActor2D()
            self.structures = None
            style = MultiStructuresInteractorStyle(self)
            self.iren.SetInteractorStyle(style)
            self.istruct = 0
            self.current_structure = None
            self.set_animated_movie_options(animated_movie_options=animated_movie_options)

        def set_structures(self, structures, tags=None):
            """
            Add list of structures to the visualizer.

            Args:
                structures (List of Structures):
                tags (): List of tags.
            """
            self.structures = structures
            self.istruct = 0
            self.current_structure = self.structures[self.istruct]
            self.tags = tags if tags is not None else []
            self.all_radii = []
            self.all_vis_radii = []
            for struct in self.structures:
                struct_radii = []
                struct_vis_radii = []
                for site in struct:
                    radius = 0
                    for specie, occu in site.species.items():
                        radius += occu * (specie.ionic_radius
                                          if isinstance(specie, Specie) and specie.ionic_radius
                                          else specie.average_ionic_radius)
                        vis_radius = 0.2 + 0.002 * radius
                    struct_radii.append(radius)
                    struct_vis_radii.append(vis_radius)
                self.all_radii.append(struct_radii)
                self.all_vis_radii.append(struct_vis_radii)
            self.set_structure(self.current_structure, reset_camera=True, to_unit_cell=False)

        def set_structure(self, structure, reset_camera=True, to_unit_cell=False):
            """
            Add a structure to the visualizer.

            Args:
                structure: structure to visualize
                reset_camera: Set to True to reset the camera to a default
                    determined based on the structure.
                to_unit_cell: Whether or not to fall back sites into the unit cell.
            """
            super().set_structure(structure=structure, reset_camera=reset_camera,
                                  to_unit_cell=to_unit_cell)
            self.apply_tags()

        def apply_tags(self):
            """
            Apply tags.
            """
            tags = {}
            for tag in self.tags:
                istruct = tag.get('istruct', 'all')
                if istruct != 'all':
                    if istruct != self.istruct:
                        continue
                site_index = tag['site_index']
                color = tag.get('color', [0.5, 0.5, 0.5])
                opacity = tag.get('opacity', 0.5)
                if site_index == 'unit_cell_all':
                    struct_radii = self.all_vis_radii[self.istruct]
                    for isite, site in enumerate(self.current_structure):
                        vis_radius = 1.5 * tag.get('radius', struct_radii[isite])
                        tags[(isite, (0, 0, 0))] = {'radius': vis_radius,
                                                    'color': color,
                                                    'opacity': opacity}
                    continue
                cell_index = tag['cell_index']
                if 'radius' in tag:
                    vis_radius = tag['radius']
                elif 'radius_factor' in tag:
                    vis_radius = tag['radius_factor'] * self.all_vis_radii[self.istruct][site_index]
                else:
                    vis_radius = 1.5 * self.all_vis_radii[self.istruct][site_index]
                tags[(site_index, cell_index)] = {'radius': vis_radius,
                                                  'color': color,
                                                  'opacity': opacity}
            for site_and_cell_index, tag_style in tags.items():
                isite, cell_index = site_and_cell_index
                site = self.current_structure[isite]
                if cell_index == (0, 0, 0):
                    coords = site.coords
                else:
                    fcoords = site.frac_coords + np.array(cell_index)
                    site_image = PeriodicSite(site.species, fcoords,
                                              self.current_structure.lattice, to_unit_cell=False,
                                              coords_are_cartesian=False,
                                              properties=site.properties)
                    self.add_site(site_image)
                    coords = site_image.coords
                vis_radius = tag_style['radius']
                color = tag_style['color']
                opacity = tag_style['opacity']
                self.add_partial_sphere(coords=coords, radius=vis_radius,
                                        color=color, start=0, end=360,
                                        opacity=opacity)

        def set_animated_movie_options(self, animated_movie_options=None):
            """
            Args:
                animated_movie_options ():
            """
            if animated_movie_options is None:
                self.animated_movie_options = self.DEFAULT_ANIMATED_MOVIE_OPTIONS.copy()
            else:
                self.animated_movie_options = self.DEFAULT_ANIMATED_MOVIE_OPTIONS.copy()
                for key in animated_movie_options:
                    if key not in self.DEFAULT_ANIMATED_MOVIE_OPTIONS.keys():
                        raise ValueError('Wrong option for animated movie')
                self.animated_movie_options.update(animated_movie_options)

        def display_help(self):
            """
            Display the help for various keyboard shortcuts.
            """
            helptxt = ["h : Toggle help",
                       "A/a, B/b or C/c : Increase/decrease cell by one a,"
                       " b or c unit vector", "# : Toggle showing of polyhedrons",
                       "-: Toggle showing of bonds", "r : Reset camera direction",
                       "[/]: Decrease or increase poly_radii_tol_factor "
                       "by 0.05. Value = " + str(self.poly_radii_tol_factor),
                       "Up/Down: Rotate view along Up direction by 90 "
                       "clockwise/anticlockwise",
                       "Left/right: Rotate view along camera direction by "
                       "90 clockwise/anticlockwise", "s: Save view to image.png",
                       "o: Orthogonalize structure",
                       "n: Move to next structure",
                       "p: Move to previous structure",
                       "m: Animated movie of the structures"]
            self.helptxt_mapper.SetInput("\n".join(helptxt))
            self.helptxt_actor.SetPosition(10, 10)
            self.helptxt_actor.VisibilityOn()

        def display_warning(self, warning):
            """
            Args:
                warning (str): Warning
            """
            self.warningtxt_mapper = vtk.vtkTextMapper()
            tprops = self.warningtxt_mapper.GetTextProperty()
            tprops.SetFontSize(14)
            tprops.SetFontFamilyToTimes()
            tprops.SetColor(1, 0, 0)
            tprops.BoldOn()
            tprops.SetJustificationToRight()
            self.warningtxt = "WARNING : {}".format(warning)
            self.warningtxt_actor = vtk.vtkActor2D()
            self.warningtxt_actor.VisibilityOn()
            self.warningtxt_actor.SetMapper(self.warningtxt_mapper)
            self.ren.AddActor(self.warningtxt_actor)
            self.warningtxt_mapper.SetInput(self.warningtxt)
            winsize = self.ren_win.GetSize()
            self.warningtxt_actor.SetPosition(winsize[0] - 10, 10)
            self.warningtxt_actor.VisibilityOn()

        def erase_warning(self):
            """
            Remove warnings.
            """
            self.warningtxt_actor.VisibilityOff()

        def display_info(self, info):
            """
            Args:
                info (str): Information.
            """
            self.infotxt_mapper = vtk.vtkTextMapper()
            tprops = self.infotxt_mapper.GetTextProperty()
            tprops.SetFontSize(14)
            tprops.SetFontFamilyToTimes()
            tprops.SetColor(0, 0, 1)
            tprops.BoldOn()
            tprops.SetVerticalJustificationToTop()
            self.infotxt = "INFO : {}".format(info)
            self.infotxt_actor = vtk.vtkActor2D()
            self.infotxt_actor.VisibilityOn()
            self.infotxt_actor.SetMapper(self.infotxt_mapper)
            self.ren.AddActor(self.infotxt_actor)
            self.infotxt_mapper.SetInput(self.infotxt)
            winsize = self.ren_win.GetSize()
            self.infotxt_actor.SetPosition(10, winsize[1] - 10)
            self.infotxt_actor.VisibilityOn()

        def erase_info(self):
            """
            Erase all info.
            """
            self.infotxt_actor.VisibilityOff()

    class MultiStructuresInteractorStyle(StructureInteractorStyle):
        """
        Interactor for MultiStructureVis.
        """
        def __init__(self, parent):
            """
            Args:
                parent ():
            """
            StructureInteractorStyle.__init__(self, parent=parent)

        def keyPressEvent(self, obj, event):
            """
            Args:
                obj ():
                event ():
            """
            parent = obj.GetCurrentRenderer().parent
            sym = parent.iren.GetKeySym()

            if sym == "n":
                if parent.istruct == len(parent.structures) - 1:
                    parent.display_warning('LAST STRUCTURE')
                    parent.ren_win.Render()
                else:
                    parent.istruct += 1
                    parent.current_structure = parent.structures[parent.istruct]
                    parent.set_structure(parent.current_structure, reset_camera=False, to_unit_cell=False)
                    parent.erase_warning()
                    parent.ren_win.Render()
            elif sym == "p":
                if parent.istruct == 0:
                    parent.display_warning('FIRST STRUCTURE')
                    parent.ren_win.Render()
                else:

                    parent.istruct -= 1
                    parent.current_structure = parent.structures[parent.istruct]
                    parent.set_structure(parent.current_structure, reset_camera=False, to_unit_cell=False)
                    parent.erase_warning()
                    parent.ren_win.Render()
            elif sym == "m":
                parent.istruct = 0
                parent.current_structure = parent.structures[parent.istruct]
                parent.set_structure(parent.current_structure, reset_camera=False, to_unit_cell=False)
                parent.erase_warning()
                parent.ren_win.Render()
                nloops = parent.animated_movie_options['number_of_loops']
                tstep = parent.animated_movie_options['time_between_frames']
                tloops = parent.animated_movie_options['time_between_loops']
                if parent.animated_movie_options['looping_type'] == 'restart':
                    loop_istructs = range(len(parent.structures))
                elif parent.animated_movie_options['looping_type'] == 'palindrome':
                    loop_istructs = range(len(parent.structures)) + range(len(parent.structures) - 2, -1, -1)
                else:
                    raise ValueError('"looping_type" should be "restart" or "palindrome"')
                for iloop in range(nloops):
                    for istruct in loop_istructs:
                        time.sleep(tstep)
                        parent.istruct = istruct
                        parent.current_structure = parent.structures[parent.istruct]
                        parent.set_structure(parent.current_structure, reset_camera=False, to_unit_cell=False)
                        parent.display_info('Animated movie : structure {:d}/{:d} '
                                            '(loop {:d}/{:d})'.format(istruct + 1, len(parent.structures),
                                                                      iloop + 1, nloops))
                        parent.ren_win.Render()
                    time.sleep(tloops)
                parent.erase_info()
                parent.display_info('Ended animated movie ...')
                parent.ren_win.Render()

            StructureInteractorStyle.keyPressEvent(self, obj, event)