ConstructTree

#include <vtkGraphLayoutView.h>
#include <vtkMutableDirectedGraph.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkTree.h>

int main(int, char*[])
{
  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkMutableDirectedGraph> graph;

  vtkIdType v1 = graph->AddVertex();
  vtkIdType v2 = graph->AddChild(v1);
  graph->AddChild(v1);
  graph->AddChild(v2);

  /*
  //equivalent to:

  vtkIdType v1 = g->AddVertex();
  vtkIdType v2 = g->AddVertex();
  vtkIdType v3 = g->AddVertex();
  vtkIdType v4 = g->AddVertex();

  g->AddEdge ( v1, v2 );
  g->AddEdge ( v1, v3 );
  g->AddEdge ( v2, v4 );
  */

  vtkNew<vtkTree> tree;
  bool success = tree->CheckedShallowCopy(graph);
  std::cout << "Success? " << success << std::endl;

  vtkNew<vtkGraphLayoutView> treeLayoutView;
  treeLayoutView->AddRepresentationFromInput(tree);
  treeLayoutView->SetLayoutStrategyToTree();
  treeLayoutView->ResetCamera();
  treeLayoutView->GetRenderer()->SetBackground(
      colors->GetColor3d("Navy").GetData());
  treeLayoutView->GetRenderer()->SetBackground2(
      colors->GetColor3d("MidnightBlue").GetData());
  treeLayoutView->GetRenderWindow()->SetWindowName("ConstructTree");
  treeLayoutView->Render();
  treeLayoutView->GetInteractor()->Start();

  return EXIT_SUCCESS;
}

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(ConstructTree)

find_package(VTK COMPONENTS 
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "ConstructTree: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(ConstructTree MACOSX_BUNDLE ConstructTree.cxx )
  target_link_libraries(ConstructTree PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS ConstructTree
  MODULES ${VTK_LIBRARIES}
)

cd ConstructTree/build

cmake ..

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

make

./ConstructTree