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SmoothDiscreteFlyingEdges3D

web-test/PythonicAPI/Modelling/SmoothDiscreteFlyingEdges3D

Description

Creates surfaces from labeled data. Volume data does not always contain samples of continuous data. A volume may contain discrete integer values, often the result of segmentation. This example smooths the discrete models generated by vtkDiscreteFlyingEdges3D with vtkWindowedSincPolyDataFilter.

An option is provided to use vtkDiscreteMarchingCubes instead of vtkDiscreteFlyingEdges3D.

Seealso

DiscreteFlyingEdges3D produces rough models.

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

SmoothDiscreteFlyingEdges3D.py

#!/usr/bin/env python3


from dataclasses import dataclass

# noinspection PyUnresolvedReferences
import vtkmodules.vtkInteractionStyle
# noinspection PyUnresolvedReferences
import vtkmodules.vtkRenderingOpenGL2
from vtkmodules.vtkCommonColor import vtkNamedColors
from vtkmodules.vtkCommonCore import (
    vtkLookupTable,
    vtkMinimalStandardRandomSequence
)
from vtkmodules.vtkCommonDataModel import (
    vtkImageData,
    vtkSphere
)
from vtkmodules.vtkFiltersCore import vtkWindowedSincPolyDataFilter
from vtkmodules.vtkFiltersGeneral import (
    vtkDiscreteFlyingEdges3D,
    vtkDiscreteMarchingCubes
)
from vtkmodules.vtkImagingCore import vtkImageThreshold
from vtkmodules.vtkImagingHybrid import vtkSampleFunction
from vtkmodules.vtkImagingMath import vtkImageMathematics
from vtkmodules.vtkRenderingCore import (
    vtkActor,
    vtkPolyDataMapper,
    vtkRenderWindow,
    vtkRenderWindowInteractor,
    vtkRenderer
)


def get_program_parameters():
    import argparse
    description = 'Create surfaces from labeled data and smooth them.'
    epilogue = '''
    '''
    parser = argparse.ArgumentParser(description=description, epilog=epilogue,
                                     formatter_class=argparse.RawDescriptionHelpFormatter)
    parser.add_argument('-m', '--marching_cubes', action='store_false',
                        help='Use Marching Cubes instead of Flying Edges.')
    args = parser.parse_args()
    return args.marching_cubes


def main():
    use_flying_edges = get_program_parameters()

    colors = vtkNamedColors()

    # Create the RenderWindow, Renderer, Interactor
    ren = vtkRenderer(background=colors.GetColor3d('Burlywood'))
    ren_win = vtkRenderWindow(window_name='SmoothDiscreteMarchingCubes')
    ren_win.AddRenderer(ren)

    iren = vtkRenderWindowInteractor()
    iren.SetRenderWindow(ren_win)

    n = 20
    radius = 8
    blob = make_blob(n, radius)

    if use_flying_edges:
        discrete = vtkDiscreteFlyingEdges3D()
    else:
        discrete = vtkDiscreteMarchingCubes()
    discrete.GenerateValues(n, 1, n)

    smoothing_iterations = 15
    pass_band = 0.001
    feature_angle = 120.0
    smoother = vtkWindowedSincPolyDataFilter(number_of_iterations=smoothing_iterations,
                                             pass_band=pass_band, feature_angle=feature_angle,
                                             boundary_smoothing=False,
                                             feature_edge_smoothing=False,
                                             non_manifold_smoothing=True,
                                             normalize_coordinates=True)

    lut = make_colors(n)

    mapper = vtkPolyDataMapper(lookup_table=lut, scalar_range=(0, lut.number_of_colors))
    blob >> discrete >> smoother >> mapper
    actor = vtkActor(mapper=mapper)

    ren.AddActor(actor)

    ren_win.Render()

    iren.Start()


def make_blob(n, radius):
    blob_image = vtkImageData()

    max_r = 50 - 2.0 * radius
    random_sequence = vtkMinimalStandardRandomSequence(seed=5071)
    for i in range(0, n):

        x = random_sequence.GetRangeValue(-max_r, max_r)
        random_sequence.Next()
        y = random_sequence.GetRangeValue(-max_r, max_r)
        random_sequence.Next()
        z = random_sequence.GetRangeValue(-max_r, max_r)
        random_sequence.Next()

        sphere = vtkSphere(radius=radius, center=(int(x), int(y), int(z)))

        sampler = vtkSampleFunction(implicit_function=sphere, output_scalar_type=ImageCast.OutputScalarType.VTK_FLOAT,
                                    sample_dimensions=(100, 100, 100), model_bounds=(-50, 50, -50, 50, -50, 50))

        thres = vtkImageThreshold(replace_in=True, replace_out=True, in_value=i + 1, out_value=0)
        thres.ThresholdByLower(radius * radius)
        (sampler >> thres).update()
        if i == 0:
            blob_image.DeepCopy(thres.output)

        max_value = vtkImageMathematics(operation=ImageMathematics.Operation.VTK_MAX)
        ((blob_image, thres) >> max_value).update()

        blob_image.DeepCopy(max_value.output)

    return blob_image


def make_colors(n):
    """
    Generate some random colors
    :param n: The number of colors.
    :return: The lookup table.
    """

    lut = vtkLookupTable(number_of_colors=n, table_range=(0, n - 1), scale=LookupTable.Scale.VTK_SCALE_LINEAR)
    lut.Build()
    lut.table_value = (0, 0.0, 0.0, 0.0, 1.0)

    random_sequence = vtkMinimalStandardRandomSequence()
    random_sequence.SetSeed(5071)
    for i in range(1, n):
        r = random_sequence.GetRangeValue(0.4, 1)
        random_sequence.Next()
        g = random_sequence.GetRangeValue(0.4, 1)
        random_sequence.Next()
        b = random_sequence.GetRangeValue(0.4, 1)
        random_sequence.Next()
        lut.table_value = (i, r, g, b, 1.0)

    return lut


@dataclass(frozen=True)
class ImageCast:
    @dataclass(frozen=True)
    class OutputScalarType:
        VTK_CHAR: int = 2
        VTK_UNSIGNED_CHAR: int = 3
        VTK_SHORT: int = 4
        VTK_UNSIGNED_SHORT: int = 5
        VTK_INT: int = 6
        VTK_UNSIGNED_INT: int = 7
        VTK_LONG: int = 8
        VTK_UNSIGNED_LONG: int = 9
        VTK_FLOAT: int = 10
        VTK_DOUBLE: int = 11


@dataclass(frozen=True)
class ImageMathematics:
    @dataclass(frozen=True)
    class Operation:
        VTK_ADD: int = 0
        VTK_SUBTRACT: int = 1
        VTK_MULTIPLY: int = 2
        VTK_DIVIDE: int = 3
        VTK_INVERT: int = 4
        VTK_SIN: int = 5
        VTK_COS: int = 6
        VTK_EXP: int = 7
        VTK_LOG: int = 8
        VTK_ABS: int = 9
        VTK_SQR: int = 10
        VTK_SQRT: int = 11
        VTK_MIN: int = 12
        VTK_MAX: int = 13
        VTK_ATAN: int = 14
        VTK_ATAN2: int = 15
        VTK_MULTIPLYBYK: int = 16
        VTK_ADDC: int = 17
        VTK_CONJUGATE: int = 18
        VTK_COMPLEX_MULTIPLY: int = 19
        VTK_REPLACECBYK: int = 20


@dataclass(frozen=True)
class LookupTable:
    @dataclass(frozen=True)
    class Scale:
        VTK_SCALE_LINEAR: int = 0
        VTK_SCALE_LOG10: int = 1


if __name__ == '__main__':
    main()