ExtractSurface
VTKExamples/Cxx/Points/ExtractSurface
Description
This example loosely follows the most excellent paper by Curless and Levoy: "A Volumetric Method for Building Complex Models from Range Images." First it estimates normals from the points, then creates a signed distance field, followed by surface extraction of the zero-level set of the distance field.
The image was created using the Armadillo dataset
NOTE: The classes used in this example require vtk 7.1 or later.
Code
ExtractSurface.cxx
#include <vtkSmartPointer.h>
#include <vtkPLYReader.h>
#include <vtkXMLPolyDataReader.h>
#include <vtkOBJReader.h>
#include <vtkSTLReader.h>
#include <vtkPointSource.h>
#include <vtkPCANormalEstimation.h>
#include <vtkSignedDistance.h>
#include <vtkExtractSurface.h>
#include <vtkPointData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkCamera.h>
#include <vtksys/SystemTools.hxx>
static vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName);
int main (int argc, char *argv[])
{
vtkSmartPointer<vtkPolyData> polyData = ReadPolyData(argc > 1 ? argv[1] : "");;
double bounds[6];
polyData->GetBounds(bounds);
double range[3];
for (int i = 0; i < 3; ++i)
{
range[i] = bounds[2*i + 1] - bounds[2*i];
}
int sampleSize = polyData->GetNumberOfPoints() * .00005;
if (sampleSize < 10)
{
sampleSize = 10;
}
std::cout << "Sample size is: " << sampleSize << std::endl;
// Do we need to estimate normals?
vtkSmartPointer<vtkSignedDistance> distance =
vtkSmartPointer<vtkSignedDistance>::New();
if (polyData->GetPointData()->GetNormals())
{
std::cout << "Using normals from input file" << std::endl;
distance->SetInputData (polyData);
}
else
{
std::cout << "Estimating normals using PCANormalEstimation" << std::endl;
vtkSmartPointer<vtkPCANormalEstimation> normals =
vtkSmartPointer<vtkPCANormalEstimation>::New();
normals->SetInputData (polyData);
normals->SetSampleSize(sampleSize);
normals->SetNormalOrientationToGraphTraversal();
normals->FlipNormalsOn();
distance->SetInputConnection (normals->GetOutputPort());
}
std::cout << "Range: "
<< range[0] << ", "
<< range[1] << ", "
<< range[2] << std::endl;
int dimension = 256;
double radius = range[0] * .02;
radius = range[0] / static_cast<double>(dimension) * 3; // ~3 voxels
std::cout << "Radius: " << radius << std::endl;
distance->SetRadius(radius);
distance->SetDimensions(dimension, dimension, dimension);
distance->SetBounds(
bounds[0] - range[0] * .1,
bounds[1] + range[0] * .1,
bounds[2] - range[1] * .1,
bounds[3] + range[1] * .1,
bounds[4] - range[2] * .1,
bounds[5] + range[2] * .1);
vtkSmartPointer<vtkExtractSurface> surface =
vtkSmartPointer<vtkExtractSurface>::New();
surface->SetInputConnection (distance->GetOutputPort());
surface->SetRadius(radius * .99);
surface->Update();
vtkSmartPointer<vtkPolyDataMapper> surfaceMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
surfaceMapper->SetInputConnection(surface->GetOutputPort());
vtkSmartPointer<vtkActor> surfaceActor =
vtkSmartPointer<vtkActor>::New();
surfaceActor->SetMapper(surfaceMapper);
surfaceActor->GetProperty()->SetColor(1.0000,0.3882,0.2784);
// Create graphics stuff
//
vtkSmartPointer<vtkRenderer> ren1 =
vtkSmartPointer<vtkRenderer>::New();
ren1->SetBackground(.3, .4, .6);
vtkSmartPointer<vtkRenderWindow> renWin =
vtkSmartPointer<vtkRenderWindow>::New();
renWin->AddRenderer(ren1);
renWin->SetSize(512,512);
vtkSmartPointer<vtkRenderWindowInteractor> iren =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
iren->SetRenderWindow(renWin);
// Add the actors to the renderer, set the background and size
//
ren1->AddActor(surfaceActor);
// Generate an interesting view
//
ren1->ResetCamera();
ren1->GetActiveCamera()->Azimuth(120);
ren1->GetActiveCamera()->Elevation(30);
ren1->GetActiveCamera()->Dolly(1.0);
ren1->ResetCameraClippingRange();
iren->Initialize();
iren->Start();
return EXIT_SUCCESS;
}
static vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName)
{
vtkSmartPointer<vtkPolyData> polyData;
std::string extension = vtksys::SystemTools::GetFilenameExtension(std::string(fileName));
if (extension == ".ply")
{
vtkSmartPointer<vtkPLYReader> reader =
vtkSmartPointer<vtkPLYReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".vtp")
{
vtkSmartPointer<vtkXMLPolyDataReader> reader =
vtkSmartPointer<vtkXMLPolyDataReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".obj")
{
vtkSmartPointer<vtkOBJReader> reader =
vtkSmartPointer<vtkOBJReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".stl")
{
vtkSmartPointer<vtkSTLReader> reader =
vtkSmartPointer<vtkSTLReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else
{
vtkSmartPointer<vtkPointSource> points =
vtkSmartPointer<vtkPointSource>::New();
points->SetNumberOfPoints(100000);
points->SetRadius(10.0);
points->SetCenter(vtkMath::Random(-100, 100),
vtkMath::Random(-100, 100),
vtkMath::Random(-100, 100));
points->SetDistributionToShell();
points->Update();
polyData = points->GetOutput();
}
return polyData;
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(ExtractSurface)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(ExtractSurface MACOSX_BUNDLE ExtractSurface.cxx)
target_link_libraries(ExtractSurface ${VTK_LIBRARIES})
Download and Build ExtractSurface
Click here to download ExtractSurface and its CMakeLists.txt file. Once the tarball ExtractSurface.tar has been downloaded and extracted,
cd ExtractSurface/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:
./ExtractSurface
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.