KdTree
Repository source: KdTree
Description¶
This example demonstrates how to use vtkKdTree to build a tree from a vtkPoints object. Note that since AddDataSet or SetDataSet were not called, you cannot use GetDataSet.
Question
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Code¶
KdTree.cxx
#include <vtkDataSetCollection.h>
#include <vtkKdTree.h>
#include <vtkNew.h>
#include <vtkPoints.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};
vtkNew<vtkPoints> points;
points->InsertNextPoint(x);
points->InsertNextPoint(y);
points->InsertNextPoint(z);
// Create the tree
vtkNew<vtkKdTree> kDTree;
kDTree->BuildLocatorFromPoints(points);
double testPoint[3] = {2.0, 0.0, 0.0};
const auto pointCoordinates = [](const double* pt) {
std::cout << "Coordinates: " << pt[0] << " " << pt[1] << " " << pt[2]
<< std::endl;
};
// Find the closest point to TestPoint.
double closestPointDist;
vtkIdType id = kDTree->FindClosestPoint(
testPoint, closestPointDist); // vtkKdTree::FindClosestPoint: must build
// locator first
std::cout << "Test Point ";
pointCoordinates(testPoint);
std::cout << "The closest point is point " << id << std::endl;
// Get the closest point in the KD Tree from the point data.
std::cout << "Closest point ";
pointCoordinates(points->GetPoint(id));
std::cout << "Distance: " << closestPointDist << std::endl;
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(KdTree)
find_package(VTK COMPONENTS
CommonCore
CommonDataModel
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "KdTree: 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(KdTree MACOSX_BUNDLE KdTree.cxx )
target_link_libraries(KdTree PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS KdTree
MODULES ${VTK_LIBRARIES}
)
Download and Build KdTree¶
Click here to download KdTree and its CMakeLists.txt file. Once the tarball KdTree.tar has been downloaded and extracted,
cd KdTree/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:
./KdTree
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.