# Triangle

VTKExamples/Python/GeometricObjects/Triangle

### Description¶

The triangle is a primary two-dimensional cell. The triangle is defined by a counterclockwise ordered list of three points. The order of the points specifies the direction of the surface normal using the right-hand rule.

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See (Cxx), (Java), (CSharp)

Question

### Code¶

Triangle.py

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

import vtk

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

# Create a triangle
points = vtk.vtkPoints()
points.InsertNextPoint(1.0, 0.0, 0.0)
points.InsertNextPoint(0.0, 0.0, 0.0)
points.InsertNextPoint(0.0, 1.0, 0.0)

triangle = vtk.vtkTriangle()
triangle.GetPointIds().SetId(0, 0)
triangle.GetPointIds().SetId(1, 1)
triangle.GetPointIds().SetId(2, 2)

triangles = vtk.vtkCellArray()
triangles.InsertNextCell(triangle)

# Create a polydata object
trianglePolyData = vtk.vtkPolyData()

# Add the geometry and topology to the polydata
trianglePolyData.SetPoints(points)
trianglePolyData.SetPolys(triangles)

# Create mapper and actor
mapper = vtk.vtkPolyDataMapper()
mapper.SetInputData(trianglePolyData)
actor = vtk.vtkActor()
actor.GetProperty().SetColor(colors.GetColor3d("Cyan"))
actor.SetMapper(mapper)

# Create a renderer, render window, and an interactor
renderer = vtk.vtkRenderer()
renderWindow = vtk.vtkRenderWindow()
renderWindow.SetWindowName("Triangle")
renderWindowInteractor = vtk.vtkRenderWindowInteractor()
renderWindowInteractor.SetRenderWindow(renderWindow)

# Add the actors to the scene