Vol

#!/usr/bin/env python3

# noinspection PyUnresolvedReferences
import vtkmodules.vtkInteractionStyle
# noinspection PyUnresolvedReferences
import vtkmodules.vtkRenderingOpenGL2
from vtkmodules.vtkCommonColor import vtkNamedColors
from vtkmodules.vtkCommonCore import vtkDoubleArray
from vtkmodules.vtkCommonDataModel import vtkStructuredPoints
from vtkmodules.vtkFiltersCore import vtkContourFilter
from vtkmodules.vtkRenderingCore import (
    vtkActor,
    vtkPolyDataMapper,
    vtkRenderWindow,
    vtkRenderWindowInteractor,
    vtkRenderer
)


def main():
    colors = vtkNamedColors()

    renderer = vtkRenderer(background=colors.GetColor3d('SlateGray'))
    ren_win = vtkRenderWindow(size=(512, 512), window_name='Vol')
    ren_win.AddRenderer(renderer)
    iren = vtkRenderWindowInteractor()
    iren.render_window = ren_win

    sp = 1.0 / 25.0
    scalars = vtkDoubleArray(number_of_components = 1, number_of_tuples=26)
    for k in range(0, 26):
        z = -0.5 + k * sp
        k_offset = k * 26 * 26
        for j in range(0, 26):
            y = -0.5 + j * sp
            j_offset = j * 26
            for i in range(0, 26):
                x = -0.5 + i * sp
                s = x * x + y * y + z * z - (0.4 * 0.4)
                offset = i + j_offset + k_offset
                scalars.InsertTuple1(offset, s)

    # print((sp,)*3)
    vol = vtkStructuredPoints(dimensions=(26, 26, 26),origin=(-0.5, -0.5, -0.5),spacing=(sp,)*3)
    vol.point_data.SetScalars(scalars)

    contour = vtkContourFilter(value=(0, 0.0))
    contour.SetInputData(vol)

    vol_mapper = vtkPolyDataMapper(scalar_visibility=False)
    vol >> contour >> vol_mapper

    vol_actor = vtkActor(mapper=vol_mapper)
    vol_actor.property.edge_visibility = True
    vol_actor.property.color = colors.GetColor3d('Salmon')

    renderer.AddActor(vol_actor)

    # Interact with the data.
    ren_win.Render()

    iren.Start()


if __name__ == '__main__':
    main()