QuantizePolyDataPoints
VTKExamples/Cxx/PolyData/QuantizePolyDataPoints
Description
This example demonstrates how to "snap" points onto a discrete grid. This example rounds the coordinates of each point the the nearest .1
Code
QuantizePolyDataPoints.cxx
#include <vtkSmartPointer.h>
#include <vtkQuantizePolyDataPoints.h>
#include <vtkPoints.h>
#include <vtkPolyData.h>
#include <vtkPointSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkXMLPolyDataReader.h>
int main(int, char *[])
{
vtkSmartPointer<vtkPointSource> pointSource =
vtkSmartPointer<vtkPointSource>::New();
pointSource->SetNumberOfPoints(10);
pointSource->Update();
std::cout << "There are " << pointSource->GetNumberOfPoints()
<< " points." << std::endl;
vtkSmartPointer<vtkQuantizePolyDataPoints> quantizeFilter =
vtkSmartPointer<vtkQuantizePolyDataPoints>::New();
quantizeFilter->SetInputConnection(pointSource->GetOutputPort());
quantizeFilter->SetQFactor(.1);
quantizeFilter->Update();
vtkPolyData* quantized = quantizeFilter->GetOutput();
std::cout << "There are " << quantized->GetNumberOfPoints()
<< " quantized points." << std::endl;
for(vtkIdType i = 0; i < pointSource->GetOutput()->GetNumberOfPoints(); i++)
{
double pOrig[3];
double pQuantized[3];
pointSource->GetOutput()->GetPoint(i,pOrig);
quantized->GetPoints()->GetPoint(i,pQuantized);
std::cout << "Point " << i << " : ("
<< pOrig[0] << ", " << pOrig[1] << ", " << pOrig[2] << ")"
<< " (" << pQuantized[0] << ", " << pQuantized[1] << ", " << pQuantized[2]
<< ")" << std::endl;
}
vtkSmartPointer<vtkPolyDataMapper> inputMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
inputMapper->SetInputConnection(pointSource->GetOutputPort());
vtkSmartPointer<vtkActor> inputActor =
vtkSmartPointer<vtkActor>::New();
inputActor->SetMapper(inputMapper);
vtkSmartPointer<vtkPolyDataMapper> quantizedMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
quantizedMapper->SetInputConnection(quantizeFilter->GetOutputPort());
vtkSmartPointer<vtkActor> quantizedActor =
vtkSmartPointer<vtkActor>::New();
quantizedActor->SetMapper(quantizedMapper);
// There will be one render window
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->SetSize(600, 300);
// And one interactor
vtkSmartPointer<vtkRenderWindowInteractor> interactor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
interactor->SetRenderWindow(renderWindow);
// Define viewport ranges
// (xmin, ymin, xmax, ymax)
double leftViewport[4] = {0.0, 0.0, 0.5, 1.0};
double rightViewport[4] = {0.5, 0.0, 1.0, 1.0};
// Setup both renderers
vtkSmartPointer<vtkRenderer> leftRenderer =
vtkSmartPointer<vtkRenderer>::New();
renderWindow->AddRenderer(leftRenderer);
leftRenderer->SetViewport(leftViewport);
leftRenderer->SetBackground(.6, .5, .4);
vtkSmartPointer<vtkRenderer> rightRenderer =
vtkSmartPointer<vtkRenderer>::New();
renderWindow->AddRenderer(rightRenderer);
rightRenderer->SetViewport(rightViewport);
rightRenderer->SetBackground(.4, .5, .6);
// Add the sphere to the left and the cube to the right
leftRenderer->AddActor(inputActor);
rightRenderer->AddActor(quantizedActor);
leftRenderer->ResetCamera();
rightRenderer->ResetCamera();
renderWindow->Render();
interactor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(QuantizePolyDataPoints)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(QuantizePolyDataPoints MACOSX_BUNDLE QuantizePolyDataPoints.cxx)
target_link_libraries(QuantizePolyDataPoints ${VTK_LIBRARIES})
Download and Build QuantizePolyDataPoints
Click here to download QuantizePolyDataPoints and its CMakeLists.txt file. Once the tarball QuantizePolyDataPoints.tar has been downloaded and extracted,
cd QuantizePolyDataPoints/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:
./QuantizePolyDataPoints
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.