vtkRandomGraphSource can be used to create a random graph which includes points and edges.
vtkGraphLayoutView is a vtkRenderView which has its own renderer and iterator, we can use it to display graph view.

from vtk import *

# create a random graph
source = vtkRandomGraphSource()
source.SetNumberOfVertices(100)
source.SetNumberOfEdges(110)
source.StartWithTreeOn()

#create a view to display the graph
view = vtkGraphLayoutView()
view.SetLayoutStrategyToSimple2D() #SetLayoutStrategyToRandom()
view.ColorVerticesOn()
view.SetVertexColorArrayName("vertex id")
view.SetRepresentationFromInputConnection(source.GetOutputPort())

# Apply a theme to the views
theme = vtkViewTheme.CreateMellowTheme()
view.ApplyViewTheme(theme)
theme.FastDelete()
#view.GetRenderWindow().SetSize(500,500)
view.ResetCamera()
view.Render()
view.GetInteractor().Start()

we can get the following result if the source starts with tree off:

The vtkGraphLayoutView object can set different layout strategy.
There are some available layout strategies we can use: vtkFast2DLayoutStrategy, vtkCircularLayoutStrategy, vtkConeLayoutStrategy and etc.
vtkCircularLayoutStrategy example:

 from vtk import *

source = vtkRandomGraphSource()
source.SetNumberOfVertices(100)
source.SetNumberOfEdges(0)
source.StartWithTreeOff()
view = vtkGraphLayoutView()
view.ColorVerticesOn()
view.SetVertexColorArrayName("vertex id")
view.SetRepresentationFromInputConnection(source.GetOutputPort())

strategy = vtkCircularLayoutStrategy() #Assigns points to the vertices around a circle with unit radius.

view.SetLayoutStrategy( strategy )
theme = vtkViewTheme.CreateOceanTheme()
view.ApplyViewTheme(theme)
theme.FastDelete()
view.ResetCamera()
view.Render()

view.GetInteractor().Start()

 

vtkCircularLayoutStrategy

Others:

vtkFast2DLayoutStrategy


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