KdTreePointLocatorClosestPoint
VTKExamples/Cxx/DataStructures/KdTreePointLocatorClosestPoint
Description¶
This example creates a set of three points, builds a KDTree from them, then demonstrates how to find the closest point to a query point.
Code¶
KdTreePointLocatorClosestPoint.cxx
#include <vtkSmartPointer.h> #include <vtkPoints.h> #include <vtkPolyData.h> #include <vtkIdList.h> #include <vtkKdTreePointLocator.h> int main(int, char *[]) { // Setup point coordinates double x[3] = {1.0, 0.0, 0.0}; double y[3] = {0.0, 1.0, 0.0}; double z[3] = {0.0, 0.0, 1.0}; vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New(); points->InsertNextPoint(x); points->InsertNextPoint(y); points->InsertNextPoint(z); vtkSmartPointer<vtkPolyData> polydata = vtkSmartPointer<vtkPolyData>::New(); polydata->SetPoints(points); // Create the tree vtkSmartPointer<vtkKdTreePointLocator> kDTree = vtkSmartPointer<vtkKdTreePointLocator>::New(); kDTree->SetDataSet(polydata); kDTree->BuildLocator(); double testPoint[3] = {2.0, 0.0, 0.0}; // Find the closest points to TestPoint vtkIdType iD = kDTree->FindClosestPoint(testPoint); std::cout << "The closest point is point " << iD << std::endl; //Get the coordinates of the closest point double closestPoint[3]; kDTree->GetDataSet()->GetPoint(iD, closestPoint); std::cout << "Coordinates: " << closestPoint[0] << " " << closestPoint[1] << " " << closestPoint[2] << std::endl; return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(KdTreePointLocatorClosestPoint) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(KdTreePointLocatorClosestPoint MACOSX_BUNDLE KdTreePointLocatorClosestPoint.cxx) target_link_libraries(KdTreePointLocatorClosestPoint ${VTK_LIBRARIES})
Download and Build KdTreePointLocatorClosestPoint¶
Danger
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Click here to download KdTreePointLocatorClosestPoint and its CMakeLists.txt file. Once the tarball KdTreePointLocatorClosestPoint.tar has been downloaded and extracted,
cd KdTreePointLocatorClosestPoint/build
If VTK is installed:
cmake ..
If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:
cmake -DVTK_DIR:PATH=/home/me/vtk_build ..
Build the project:
make
and run it:
./KdTreePointLocatorClosestPoint
WINDOWS USERS PLEASE NOTE: Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.