TransformPolyData

Description¶

This example demonstrates how to apply a transform to a data set. It uses vtkTransformPolyDataFilter, but it can be replaced with vtkTransformFilter for different types of data sets, including vtkUnstructuredGrid and vtkStructuredGrid. vtkTransformFilter will work with vtkPolyData, too).

Other languages

See (Cxx), (Java)

Question

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Code¶

TransformPolyData.py

#!/usr/bin/env python

# noinspection PyUnresolvedReferences
import vtkmodules.vtkInteractionStyle
# noinspection PyUnresolvedReferences
import vtkmodules.vtkRenderingOpenGL2
from vtkmodules.vtkCommonColor import vtkNamedColors
from vtkmodules.vtkCommonTransforms import vtkTransform
from vtkmodules.vtkFiltersGeneral import vtkTransformPolyDataFilter
from vtkmodules.vtkFiltersSources import vtkSphereSource
from vtkmodules.vtkRenderingCore import (
    vtkActor,
    vtkPolyDataMapper,
    vtkRenderWindow,
    vtkRenderWindowInteractor,
    vtkRenderer
)


def main():
    colors = vtkNamedColors()

    # Create the polydata geometry
    sphereSource = vtkSphereSource()
    sphereSource.Update()

    # Set up the actor to display the untransformed polydata
    originalMapper = vtkPolyDataMapper()
    originalMapper.SetInputConnection(sphereSource.GetOutputPort())

    originalActor = vtkActor()
    originalActor.SetMapper(originalMapper)
    originalActor.GetProperty().SetColor(colors.GetColor3d('Blue'))

    # Set up the transform filter
    translation = vtkTransform()
    translation.Translate(1.0, 2.0, 3.0)

    transformFilter = vtkTransformPolyDataFilter()
    transformFilter.SetInputConnection(sphereSource.GetOutputPort())
    transformFilter.SetTransform(translation)
    transformFilter.Update()

    # Set up the actor to display the transformed polydata
    transformedMapper = vtkPolyDataMapper()
    transformedMapper.SetInputConnection(transformFilter.GetOutputPort())

    transformedActor = vtkActor()
    transformedActor.SetMapper(transformedMapper)
    transformedActor.GetProperty().SetColor(colors.GetColor3d('Red'))

    # Set up the rest of the visualization pipeline
    renderer = vtkRenderer()
    renderer.AddActor(originalActor)
    renderer.AddActor(transformedActor)
    renderer.SetBackground(colors.GetColor3d('Green'))

    renderWindow = vtkRenderWindow()
    renderWindow.AddRenderer(renderer)
    renderWindowInteractor = vtkRenderWindowInteractor()
    renderWindowInteractor.SetRenderWindow(renderWindow)

    renderWindow.SetWindowName('TransformPolyData')
    renderWindow.Render()

    renderWindowInteractor.Start()


if __name__ == '__main__':
    main()