# SpecularSpheres

VTKExamples/Python/Rendering/SpecularSpheres

### Description

### Code

SpecularSpheres.py

    #!/usr/bin/env python
    # -*- coding: utf-8 -*-

    import vtk

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

        # Set the background color.
        colors.SetColor("BkgColor", [26, 51, 102, 255])

        # The following lines create a sphere represented by polygons.
        sphere = vtk.vtkSphereSource()
        sphere.SetThetaResolution(100)
        sphere.SetPhiResolution(50)

        # The mapper is responsible for pushing the geometry into the graphics
        # library. It may also do color mapping, if scalars or other attributes
        # are defined.
        #
        sphereMapper = vtk.vtkPolyDataMapper()
        sphereMapper.SetInputConnection(sphere.GetOutputPort())

        # The actor is a grouping mechanism: besides the geometry (mapper), it
        # also has a property, transformation matrix, and/or texture map.
        # In this example we create eight different spheres (two rows of four
        # spheres) and set the specular lighting coefficients. A little ambient
        # is turned on so the sphere is not completely black on the back side.
        #
        sphere1 = vtk.vtkActor()
        sphere1.SetMapper(sphereMapper)
        sphere1.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere1.GetProperty().SetAmbient(0.3)
        sphere1.GetProperty().SetDiffuse(0.0)
        sphere1.GetProperty().SetSpecular(1.0)
        sphere1.GetProperty().SetSpecularPower(5.0)

        sphere2 = vtk.vtkActor()
        sphere2.SetMapper(sphereMapper)
        sphere2.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere2.GetProperty().SetAmbient(0.3)
        sphere2.GetProperty().SetDiffuse(0.0)
        sphere2.GetProperty().SetSpecular(1.0)
        sphere2.GetProperty().SetSpecularPower(10.0)
        sphere2.AddPosition(1.25, 0, 0)

        sphere3 = vtk.vtkActor()
        sphere3.SetMapper(sphereMapper)
        sphere3.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere3.GetProperty().SetAmbient(0.3)
        sphere3.GetProperty().SetDiffuse(0.0)
        sphere3.GetProperty().SetSpecular(1.0)
        sphere3.GetProperty().SetSpecularPower(20.0)
        sphere3.AddPosition(2.5, 0, 0)

        sphere4 = vtk.vtkActor()
        sphere4.SetMapper(sphereMapper)
        sphere4.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere4.GetProperty().SetAmbient(0.3)
        sphere4.GetProperty().SetDiffuse(0.0)
        sphere4.GetProperty().SetSpecular(1.0)
        sphere4.GetProperty().SetSpecularPower(40.0)
        sphere4.AddPosition(3.75, 0, 0)

        sphere5 = vtk.vtkActor()
        sphere5.SetMapper(sphereMapper)
        sphere5.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere5.GetProperty().SetAmbient(0.3)
        sphere5.GetProperty().SetDiffuse(0.0)
        sphere5.GetProperty().SetSpecular(0.5)
        sphere5.GetProperty().SetSpecularPower(5.0)
        sphere5.AddPosition(0.0, 1.25, 0)

        sphere6 = vtk.vtkActor()
        sphere6.SetMapper(sphereMapper)
        sphere6.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere6.GetProperty().SetAmbient(0.3)
        sphere6.GetProperty().SetDiffuse(0.0)
        sphere6.GetProperty().SetSpecular(0.5)
        sphere6.GetProperty().SetSpecularPower(10.0)
        sphere6.AddPosition(1.25, 1.25, 0)

        sphere7 = vtk.vtkActor()
        sphere7.SetMapper(sphereMapper)
        sphere7.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere7.GetProperty().SetAmbient(0.3)
        sphere7.GetProperty().SetDiffuse(0.0)
        sphere7.GetProperty().SetSpecular(0.5)
        sphere7.GetProperty().SetSpecularPower(20.0)
        sphere7.AddPosition(2.5, 1.25, 0)

        sphere8 = vtk.vtkActor()
        sphere8.SetMapper(sphereMapper)
        sphere8.GetProperty().SetColor(colors.GetColor3d("Red"))
        sphere8.GetProperty().SetAmbient(0.3)
        sphere8.GetProperty().SetDiffuse(0.0)
        sphere8.GetProperty().SetSpecular(0.5)
        sphere8.GetProperty().SetSpecularPower(40.0)
        sphere8.AddPosition(3.75, 1.25, 0)

        # Create the graphics structure. The renderer renders into the
        # render window. The render window interactor captures mouse events
        # and will perform appropriate camera or actor manipulation
        # depending on the nature of the events.
        #
        ren = vtk.vtkRenderer()
        renWin = vtk.vtkRenderWindow()
        renWin.AddRenderer(ren)
        iren = vtk.vtkRenderWindowInteractor()
        iren.SetRenderWindow(renWin)

        # Add the actors to the renderer, set the background and size.
        #
        ren.AddActor(sphere1)
        ren.AddActor(sphere2)
        ren.AddActor(sphere3)
        ren.AddActor(sphere4)
        ren.AddActor(sphere5)
        ren.AddActor(sphere6)
        ren.AddActor(sphere7)
        ren.AddActor(sphere8)
        ren.SetBackground(colors.GetColor3d("BkgColor"))
        renWin.SetSize(640, 480)

        # Set up the lighting.
        #
        light = vtk.vtkLight()
        light.SetFocalPoint(1.875, 0.6125, 0)
        light.SetPosition(0.875, 1.6125, 1)
        ren.AddLight(light)

        # We want to eliminate perspective effects on the apparent lighting.
        # Parallel camera projection will be used. To zoom in parallel projection
        # mode, the ParallelScale is set.
        #
        ren.GetActiveCamera().SetFocalPoint(0, 0, 0)
        ren.GetActiveCamera().SetPosition(0, 0, 1)
        ren.GetActiveCamera().SetViewUp(0, 1, 0)
        ren.GetActiveCamera().ParallelProjectionOn()
        ren.ResetCamera()
        ren.GetActiveCamera().SetParallelScale(1.5)

        # This starts the event loop and invokes an initial render.
        #
        iren.Initialize()
        iren.Start()

    if __name__ == "__main__":
        main()