Curvatures

#!/usr/bin/env python3

from dataclasses import dataclass
from pathlib import Path

import numpy as np
from vtk.util import numpy_support
from vtkmodules.numpy_interface import dataset_adapter as dsa
from vtkmodules.vtkCommonColor import (
    vtkColorSeries,
    vtkNamedColors
)
from vtkmodules.vtkCommonCore import (
    VTK_DOUBLE,
    vtkIdList
)
from vtkmodules.vtkFiltersCore import (
    vtkFeatureEdges,
    vtkGenerateIds
)
from vtkmodules.vtkFiltersGeneral import vtkCurvatures
# noinspection PyUnresolvedReferences
from vtkmodules.vtkIOXML import (
    vtkXMLPolyDataReader,
    vtkXMLPolyDataWriter,
    vtkXMLWriterBase,
)
from vtkmodules.vtkInteractionWidgets import (
    vtkCameraOrientationWidget,
    vtkScalarBarRepresentation,
    vtkScalarBarWidget,
)
from vtkmodules.vtkRenderingAnnotation import vtkScalarBarActor
from vtkmodules.vtkRenderingCore import (
    vtkActor,
    vtkColorTransferFunction,
    vtkPolyDataMapper,
    vtkRenderWindow,
    vtkRenderWindowInteractor,
    vtkRenderer,
    vtkTextProperty
)


def get_program_parameters(argv):
    import argparse
    import textwrap

    description = 'Calculate Gauss or Mean Curvature.'
    epilogue = textwrap.dedent('''
    ''')
    parser = argparse.ArgumentParser(formatter_class=argparse.RawDescriptionHelpFormatter, description=description,
                                     epilog=epilogue)
    parser.add_argument('file_name', help=' e.g. cowHead.vtp.')
    parser.add_argument('-i', default=16, type=int, help='The color map index e.g. 16.')
    parser.add_argument('-g', help='Use Gaussian Curvature.', action='store_true')
    parser.add_argument('-w', help='Write out the polydata.', action='store_true')

    args = parser.parse_args()
    return args.file_name, args.i, args.g, args.w


def main(argv):
    file_name, color_map_idx, gaussian_curvature, save_pd = get_program_parameters(argv)

    if not Path(file_name).is_file():
        print(f'The path: {file_name} does not exist.')
        return
    if gaussian_curvature:
        curvature = 'Gauss_Curvature'
    else:
        curvature = 'Mean_Curvature'

    reader = vtkXMLPolyDataReader(file_name=file_name)

    source = reader.update().output

    if gaussian_curvature:
        cc = vtkCurvatures(curvature_type=Curvatures.CurvatureType.VTK_CURVATURE_GAUSS)
    else:
        cc = vtkCurvatures(curvature_type=Curvatures.CurvatureType.VTK_CURVATURE_MEAN)
    p = (source >> cc).update().output
    adjust_edge_curvatures(p, curvature)
    source.point_data.AddArray(p.point_data.GetAbstractArray(curvature))
    scalar_range = source.point_data.GetScalars(curvature).range

    if save_pd:
        writer = vtkXMLPolyDataWriter(input_data=source, file_name='Source.vtp', data_mode=vtkXMLWriterBase.Ascii)
        writer.Write()

    # Build a lookup table
    color_series = vtkColorSeries(color_scheme=color_map_idx)
    print(f'Using color scheme #: {color_series.GetColorScheme()}, {color_series.GetColorSchemeName()}')

    lut = vtkColorTransferFunction(color_space=ColorTransferFunction.ColorSpace.VTK_CTF_HSV)

    # Use a color series to create a transfer function
    for i in range(0, color_series.GetNumberOfColors()):
        color = color_series.GetColor(i)
        double_color = list(map(lambda x: x / 255.0, color))
        t = scalar_range[0] + (scalar_range[1] - scalar_range[0]) / (color_series.GetNumberOfColors() - 1) * i
        lut.AddRGBPoint(t, double_color[0], double_color[1], double_color[2])

    colors = vtkNamedColors()

    # Create a mapper and actor.
    mapper = vtkPolyDataMapper(scalar_range=scalar_range, lookup_table=lut,
                               scalar_mode=Mapper.ScalarMode.VTK_SCALAR_MODE_USE_POINT_FIELD_DATA)
    mapper.SelectColorArray(curvature)

    actor = vtkActor(mapper=mapper)
    p >> mapper

    window_width = 800
    window_height = 800

    # Create a scalar bar
    # Set up the scalar bar properties.
    scalar_bar_properties = ScalarBarProperties()
    scalar_bar_properties.title_text = curvature.replace('_', '\n') + '\n'
    scalar_bar_properties.number_of_labels = 5
    scalar_bar_properties.maximum_dimensions['height'] = window_height
    scalar_bar_properties.lut = lut
    scalar_bar_properties.position_v['point0'] = (0.85, 0.1)
    scalar_bar_properties.position_v['point2'] = (0.1, 0.65)

    # Create a renderer, render window, and interactor
    renderer = vtkRenderer(background=colors.GetColor3d('DarkSlateGray'))
    ren_win = vtkRenderWindow(size=(window_width, window_height), window_name='Curvatures')
    ren_win.AddRenderer(renderer)

    iren = vtkRenderWindowInteractor()
    iren.render_window = ren_win
    # Important: The interactor must be set prior to enabling the widget.
    iren.render_window = ren_win

    text_property = vtkTextProperty(color=colors.GetColor3d('AliceBlue'), bold=True, italic=True, shadow=True,
                                    font_size=16,
                                    justification=TextProperty.Justification.VTK_TEXT_LEFT)
    scalar_bar_widget = make_scalar_bar_widget(scalar_bar_properties, text_property, iren)
    scalar_bar_widget.default_renderer = renderer

    cam_orient_manipulator = vtkCameraOrientationWidget(parent_renderer=renderer)
    # Enable the widget.
    cam_orient_manipulator.On()

    # Add the actors to the scene
    renderer.AddActor(actor)
    renderer.SetBackground(colors.GetColor3d('DarkSlateGray'))

    # Render and interact
    ren_win.Render()
    iren.Start()


def adjust_edge_curvatures(source, curvature_name, epsilon=1.0e-08):
    """
    This function adjusts curvatures along the edges of the surface by replacing
     the value with the average value of the curvatures of points in the neighborhood.

    :param source: The vtkCurvatures object.
    :param curvature_name: The name of the curvature, 'Gauss_Curvature' or 'Mean_Curvature'.
    :param epsilon: Absolute curvature values less than this will be set to zero.
    :return:
    """

    def point_neighbourhood(pt_id):
        """
        Extract the topological neighbors for point.

        :param pt_id: The point id.
        :return: The neighbour ids.
        """
        cell_ids = vtkIdList()
        source.GetPointCells(pt_id, cell_ids)
        neighbour = set()
        for cell_idx in range(0, cell_ids.GetNumberOfIds()):
            cell_id = cell_ids.GetId(cell_idx)
            cell_point_ids = vtkIdList()
            source.GetCellPoints(cell_id, cell_point_ids)
            for cell_pt_idx in range(0, cell_point_ids.GetNumberOfIds()):
                neighbour.add(cell_point_ids.GetId(cell_pt_idx))
        return neighbour

    def compute_distance(pt_id_a, pt_id_b):
        """
        Compute the distance between two points given their ids.

        :param pt_id_a: First point.
        :param pt_id_b: Second point.
        :return: The distance.
        """
        pt_a = np.array(source.GetPoint(pt_id_a))
        pt_b = np.array(source.GetPoint(pt_id_b))
        return np.linalg.norm(pt_a - pt_b)

    # Get the active scalars
    source.point_data.SetActiveScalars(curvature_name)
    np_source = dsa.WrapDataObject(source)
    curvatures = np_source.PointData[curvature_name]

    #  Get the boundary point IDs.
    array_name = 'ids'
    id_filter = vtkGenerateIds(point_ids=True, cell_ids=False,
                               point_ids_array_name=array_name,
                               cell_ids_array_name=array_name)

    edges = vtkFeatureEdges(boundary_edges=True, manifold_edges=False,
                            non_manifold_edges=False, feature_edges=False)

    (source >> id_filter >> edges).update()

    edge_array = edges.output.GetPointData().GetArray(array_name)
    boundary_ids = []
    for i in range(edges.output.GetNumberOfPoints()):
        boundary_ids.append(edge_array.GetValue(i))
    # Remove duplicate Ids.
    p_ids_set = set(boundary_ids)

    # Iterate over the edge points and compute the curvature as the weighted
    # average of the neighbours.
    count_invalid = 0
    for p_id in boundary_ids:
        p_ids_neighbors = point_neighbourhood(p_id)
        # Keep only interior points.
        p_ids_neighbors -= p_ids_set
        # Compute distances and extract curvature values.
        curvs = [curvatures[p_id_n] for p_id_n in p_ids_neighbors]
        dists = [compute_distance(p_id_n, p_id) for p_id_n in p_ids_neighbors]
        curvs = np.array(curvs)
        dists = np.array(dists)
        curvs = curvs[dists > 0]
        dists = dists[dists > 0]
        if len(curvs) > 0:
            weights = 1 / np.array(dists)
            weights /= weights.sum()
            new_curv = np.dot(curvs, weights)
        else:
            # Corner case.
            count_invalid += 1
            # Assuming the curvature of the point is planar.
            new_curv = 0.0
        # Set the new curvature value.
        curvatures[p_id] = new_curv

    #  Set small values to zero.
    if epsilon != 0.0:
        curvatures = np.where(abs(curvatures) < epsilon, 0, curvatures)
        curv = numpy_support.numpy_to_vtk(num_array=curvatures.ravel(),
                                          deep=True,
                                          array_type=VTK_DOUBLE)
        curv.name = curvature_name
        source.point_data.RemoveArray(curvature_name)
        source.point_data.AddArray(curv)
        source.point_data.active_scalars = curvature_name


class ScalarBarProperties:
    """
    The properties needed for scalar bars.
    """
    named_colors = vtkNamedColors()

    lut = None
    # These are in pixels
    maximum_dimensions = {'width': 100, 'height': 260}
    title_text = '',
    number_of_labels: int = 5
    # Orientation vertical=True, horizontal=False
    orientation: bool = True
    # Horizontal and vertical positioning
    position_v = {'point1': (0.85, 0.1), 'point2': (0.1, 0.7)}
    position_h = {'point1': (0.10, 0.1), 'point2': (0.7, 0.1)}


def make_scalar_bar_widget(scalar_bar_properties, text_property, interactor):
    """
    Make a scalar bar widget.

    :param scalar_bar_properties: The lookup table, title name, maximum dimensions in pixels and position.
    :param text_property: The properties for the title.
    :param interactor: The vtkInteractor.
    :return: The scalar bar widget.
    """
    sb_actor = vtkScalarBarActor(lookup_table=scalar_bar_properties.lut, title=scalar_bar_properties.title_text,
                                 unconstrained_font_size=True, number_of_labels=scalar_bar_properties.number_of_labels,
                                 title_text_property=text_property
                                 )

    sb_rep = vtkScalarBarRepresentation(enforce_normalized_viewport_bounds=True,
                                        orientation=scalar_bar_properties.orientation)

    # Set the position
    sb_rep.position_coordinate.SetCoordinateSystemToNormalizedViewport()
    sb_rep.position2_coordinate.SetCoordinateSystemToNormalizedViewport()
    if scalar_bar_properties.orientation:
        sb_rep.position_coordinate.value = scalar_bar_properties.position_v['point1']
        sb_rep.position2_coordinate.value = scalar_bar_properties.position_v['point2']
    else:
        sb_rep.position_coordinate.value = scalar_bar_properties.position_h['point1']
        sb_rep.position2_coordinate.value = scalar_bar_properties.position_h['point2']

    widget = vtkScalarBarWidget(representation=sb_rep, scalar_bar_actor=sb_actor, interactor=interactor, enabled=True)

    return widget


@dataclass(frozen=True)
class ColorTransferFunction:
    @dataclass(frozen=True)
    class ColorSpace:
        VTK_CTF_RGB: int = 0
        VTK_CTF_HSV: int = 1
        VTK_CTF_LAB: int = 2
        VTK_CTF_DIVERGING: int = 3
        VTK_CTF_LAB_CIEDE2000: int = 4
        VTK_CTF_STEP: int = 5

    @dataclass(frozen=True)
    class Scale:
        VTK_CTF_LINEAR: int = 0
        VTK_CTF_LOG10: int = 1


@dataclass(frozen=True)
class Curvatures:
    @dataclass(frozen=True)
    class CurvatureType:
        VTK_CURVATURE_GAUSS: int = 0
        VTK_CURVATURE_MEAN: int = 1
        VTK_CURVATURE_MAXIMUM: int = 2
        VTK_CURVATURE_MINIMUM: int = 3


@dataclass(frozen=True)
class Mapper:
    @dataclass(frozen=True)
    class ColorMode:
        VTK_COLOR_MODE_DEFAULT: int = 0
        VTK_COLOR_MODE_MAP_SCALARS: int = 1
        VTK_COLOR_MODE_DIRECT_SCALARS: int = 2

    @dataclass(frozen=True)
    class ScalarMode:
        VTK_SCALAR_MODE_DEFAULT: int = 0
        VTK_SCALAR_MODE_USE_POINT_DATA: int = 1
        VTK_SCALAR_MODE_USE_CELL_DATA: int = 2
        VTK_SCALAR_MODE_USE_POINT_FIELD_DATA: int = 3
        VTK_SCALAR_MODE_USE_CELL_FIELD_DATA: int = 4
        VTK_SCALAR_MODE_USE_FIELD_DATA: int = 5


@dataclass(frozen=True)
class TextProperty:
    @dataclass(frozen=True)
    class Justification:
        VTK_TEXT_LEFT: int = 0
        VTK_TEXT_CENTERED: int = 1
        VTK_TEXT_RIGHT: int = 2

    @dataclass(frozen=True)
    class VerticalJustification:
        VTK_TEXT_BOTTOM: int = 0
        VTK_TEXT_CENTERED: int = 1
        VTK_TEXT_TOP: int = 2


if __name__ == '__main__':
    import sys

    main(sys.argv)