# Polygon

VTKExamples/Python/GeometricObjects/Polygon

### Code

Polygon.py

    #!/usr/bin/env python

    import vtk

    # Setup four points
    points = vtk.vtkPoints()
    points.InsertNextPoint(0.0, 0.0, 0.0)
    points.InsertNextPoint(1.0, 0.0, 0.0)
    points.InsertNextPoint(1.0, 1.0, 0.0)
    points.InsertNextPoint(0.0, 1.0, 0.0)

    # Create the polygon
    polygon = vtk.vtkPolygon()
    polygon.GetPointIds().SetNumberOfIds(4)  # make a quad
    polygon.GetPointIds().SetId(0, 0)
    polygon.GetPointIds().SetId(1, 1)
    polygon.GetPointIds().SetId(2, 2)
    polygon.GetPointIds().SetId(3, 3)

    # Add the polygon to a list of polygons
    polygons = vtk.vtkCellArray()
    polygons.InsertNextCell(polygon)

    # Create a PolyData
    polygonPolyData = vtk.vtkPolyData()
    polygonPolyData.SetPoints(points)
    polygonPolyData.SetPolys(polygons)

    # Create a mapper and actor
    mapper = vtk.vtkPolyDataMapper()
    if vtk.VTK_MAJOR_VERSION <= 5:
        mapper.SetInput(polygonPolyData)
    else:
        mapper.SetInputData(polygonPolyData)

    actor = vtk.vtkActor()
    actor.SetMapper(mapper)

    # Visualize
    renderer = vtk.vtkRenderer()
    renderWindow = vtk.vtkRenderWindow()
    renderWindow.AddRenderer(renderer)
    renderWindowInteractor = vtk.vtkRenderWindowInteractor()
    renderWindowInteractor.SetRenderWindow(renderWindow)

    renderer.AddActor(actor)
    renderer.SetBackground(.5, .3, .31)  # Background color salmon

    renderWindow.Render()
    renderWindowInteractor.Start()