Boolean

VTKExamples/Python/ImplicitFunctions/Boolean


Description

Demonstration on how to perform boolean operations with implicit functions.

Question

If you have a simple question about this example contact us at VTKExamplesProject If your question is more complex and may require extended discussion, please use the VTK Discourse Forum

Code

Boolean.py

import vtk


def main():
    colors = vtk.vtkNamedColors()

    # create a sphere
    sphere = vtk.vtkSphere()
    sphere.SetRadius(1)
    sphere.SetCenter(1, 0, 0)

    # create a box
    box = vtk.vtkBox()
    box.SetBounds(-1, 1, -1, 1, -1, 1)

    # combine the two implicit functions
    boolean = vtk.vtkImplicitBoolean()
    boolean.SetOperationTypeToDifference()
    # boolean.SetOperationTypeToUnion()
    # boolean.SetOperationTypeToIntersection()
    boolean.AddFunction(box)
    boolean.AddFunction(sphere)

    # The sample function generates a distance function from the implicit
    # function. This is then contoured to get a polygonal surface.
    sample = vtk.vtkSampleFunction()
    sample.SetImplicitFunction(boolean)
    sample.SetModelBounds(-1, 2, -1, 1, -1, 1)
    sample.SetSampleDimensions(40, 40, 40)
    sample.ComputeNormalsOff()

    # contour
    surface = vtk.vtkContourFilter()
    surface.SetInputConnection(sample.GetOutputPort())
    surface.SetValue(0, 0.0)

    # mapper
    mapper = vtk.vtkPolyDataMapper()
    mapper.SetInputConnection(surface.GetOutputPort())
    mapper.ScalarVisibilityOff()
    actor = vtk.vtkActor()
    actor.SetMapper(mapper)
    actor.GetProperty().EdgeVisibilityOn()
    actor.GetProperty().SetColor(colors.GetColor3d('AliceBlue'))
    actor.GetProperty().SetEdgeColor(colors.GetColor3d('SteelBlue'))

    # A renderer and render window
    renderer = vtk.vtkRenderer()
    renderer.SetBackground(colors.GetColor3d('Silver'))

    # add the actor
    renderer.AddActor(actor)

    # render window
    renwin = vtk.vtkRenderWindow()
    renwin.AddRenderer(renderer)

    # An interactor
    interactor = vtk.vtkRenderWindowInteractor()
    interactor.SetRenderWindow(renwin)

    # Start
    interactor.Initialize()
    renwin.Render()
    # renderer.GetActiveCamera().AddObserver('ModifiedEvent', CameraModifiedCallback)
    renderer.GetActiveCamera().SetPosition(5.0, -4.0, 1.6)
    renderer.GetActiveCamera().SetViewUp(0.1, 0.5, 0.9)
    renderer.GetActiveCamera().SetDistance(6.7)
    renwin.Render()
    interactor.Start()


if __name__ == '__main__':
    main()