SubdivisionDemo
VTKEx/Cxx/Meshes/SubdivisionDemo
Question
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Code¶
SubdivisionDemo.cxx
#include <vtkActor.h>
#include <vtkButterflySubdivisionFilter.h>
#include <vtkCamera.h>
#include <vtkCellArray.h>
#include <vtkCellData.h>
#include <vtkColor.h>
#include <vtkDoubleArray.h>
#include <vtkLegendBoxActor.h>
#include <vtkLinearSubdivisionFilter.h>
#include <vtkLoopSubdivisionFilter.h>
#include <vtkNamedColors.h>
#include <vtkPointData.h>
#include <vtkPoints.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkTriangle.h>
#include <vtkTriangleFilter.h>
#include <vtkXMLPolyDataReader.h>
// Readers
#include <vtkBYUReader.h>
#include <vtkOBJReader.h>
#include <vtkPLYReader.h>
#include <vtkPolyDataReader.h>
#include <vtkSTLReader.h>
#include <vtkXMLPolyDataReader.h>
#include <vtkPolyData.h>
#include <vtkSphereSource.h>
#include <algorithm> // For transform()
#include <cctype> // For to_lower
#include <string> // For find_last_of()
namespace {
vtkSmartPointer<vtkPolyData> ReadPolyData(std::string const& fileName);
}
int main(int argc, char* argv[])
{
// Test with these parameters: footbones.ply 2
int numberOfSubdivisions = 2;
auto polyData = ReadPolyData(argc > 1 ? argv[1] : "");
vtkSmartPointer<vtkPolyData> originalMesh; /* =
vtkSmartPointer<vtkPolyData>::New();*/
if (argc > 1) // If a file name is specified, open and use the file.
{
// Subdivision filters only work on triangles
auto triangles = vtkSmartPointer<vtkTriangleFilter>::New();
triangles->SetInputData(polyData);
triangles->Update();
originalMesh = triangles->GetOutput();
}
else
{
originalMesh = polyData;
}
if (argc > 2)
{
numberOfSubdivisions = std::stod(argv[2]);
}
std::cout << "Before subdivision" << std::endl;
std::cout << " There are " << originalMesh->GetNumberOfPoints()
<< " points." << std::endl;
std::cout << " There are " << originalMesh->GetNumberOfPolys()
<< " triangles." << std::endl;
auto colors = vtkSmartPointer<vtkNamedColors>::New();
vtkColor3d background = colors->GetColor3d("Gray");
vtkColor3d originalColor = colors->GetColor3d("Tomato");
vtkColor3d loopColor = colors->GetColor3d("Banana");
vtkColor3d butterflyColor = colors->GetColor3d("DodgerBlue");
double numberOfViewports = 3.0;
auto renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->SetSize(400 * numberOfViewports, 512); //(width, height)
auto renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
auto camera = vtkSmartPointer<vtkCamera>::New();
auto legend = vtkSmartPointer<vtkLegendBoxActor>::New();
legend->SetNumberOfEntries(3);
auto legendRen = vtkSmartPointer<vtkRenderer>::New();
for (unsigned i = 0; i < numberOfViewports; i++)
{
// Note: Here we create a superclass pointer (vtkPolyDataAlgorithm) so
// that we can easily instantiate different types of subdivision filters.
// Typically you would not want to do this, but rather create the pointer
// to be the type filter you will actually use, e.g.
// vtkSmartPointer<vtkLinearSubdivisionFilter> subdivisionFilter =
// vtkSmartPointer<vtkLinearSubdivisionFilter>::New();
vtkSmartPointer<vtkPolyDataAlgorithm> subdivisionFilter;
auto renderer = vtkSmartPointer<vtkRenderer>::New();
auto actor = vtkSmartPointer<vtkActor>::New();
switch (i)
{
case 0:
subdivisionFilter = vtkSmartPointer<vtkLinearSubdivisionFilter>::New();
dynamic_cast<vtkLinearSubdivisionFilter*>(subdivisionFilter.GetPointer())
->SetNumberOfSubdivisions(numberOfSubdivisions);
actor->GetProperty()->SetDiffuseColor(originalColor.GetData());
legend->SetEntry(i, subdivisionFilter->GetOutput(), "Linear",
originalColor.GetData());
break;
case 1:
subdivisionFilter = vtkSmartPointer<vtkLoopSubdivisionFilter>::New();
dynamic_cast<vtkLoopSubdivisionFilter*>(subdivisionFilter.GetPointer())
->SetNumberOfSubdivisions(numberOfSubdivisions);
actor->GetProperty()->SetDiffuseColor(loopColor.GetData());
legend->SetEntry(i, subdivisionFilter->GetOutput(), "Loop",
loopColor.GetData());
break;
case 2:
subdivisionFilter = vtkSmartPointer<vtkButterflySubdivisionFilter>::New();
dynamic_cast<vtkButterflySubdivisionFilter*>(
subdivisionFilter.GetPointer())
->SetNumberOfSubdivisions(numberOfSubdivisions);
actor->GetProperty()->SetDiffuseColor(butterflyColor.GetData());
legend->SetEntry(i, subdivisionFilter->GetOutput(), "Butterfly",
butterflyColor.GetData());
break;
default:
break;
}
subdivisionFilter->SetInputData(originalMesh);
subdivisionFilter->Update();
renderWindow->AddRenderer(renderer);
// We reserve the lower part of the viewport for the legend.
renderer->SetViewport(static_cast<double>(i) / numberOfViewports, 0.2,
static_cast<double>(i + 1) / numberOfViewports, 1);
renderer->SetBackground(background.GetData());
renderer->SetActiveCamera(camera);
renderer->UseHiddenLineRemovalOn();
// Create a mapper and actor
auto mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
mapper->SetInputConnection(subdivisionFilter->GetOutputPort());
actor->SetMapper(mapper);
renderer->AddActor(actor);
renderer->ResetCamera();
}
// Position the legend below the three viewports defined above.
legend->GetPositionCoordinate()->SetCoordinateSystemToView();
legend->GetPositionCoordinate()->SetValue(-0.3, -0.9);
legend->GetPosition2Coordinate()->SetCoordinateSystemToView();
legend->GetPosition2Coordinate()->SetValue(0.3, 0.9);
legend->BorderOff();
legendRen->AddActor(legend);
legendRen->SetBackground(background.GetData());
legendRen->SetViewport(0.0, 0.0, 1.0, 0.2);
renderWindow->AddRenderer(legendRen);
renderWindow->Render();
renderWindow->SetWindowName("Multiple ViewPorts");
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
namespace {
vtkSmartPointer<vtkPolyData> ReadPolyData(std::string const& fileName)
{
vtkSmartPointer<vtkPolyData> polyData;
std::string extension = "";
if (fileName.find_last_of(".") != std::string::npos)
{
extension = fileName.substr(fileName.find_last_of("."));
}
// Make the extension lowercase
std::transform(extension.begin(), extension.end(), extension.begin(),
::tolower);
if (extension == ".ply")
{
auto reader = vtkSmartPointer<vtkPLYReader>::New();
reader->SetFileName(fileName.c_str());
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".vtp")
{
auto reader = vtkSmartPointer<vtkXMLPolyDataReader>::New();
reader->SetFileName(fileName.c_str());
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".obj")
{
auto reader = vtkSmartPointer<vtkOBJReader>::New();
reader->SetFileName(fileName.c_str());
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".stl")
{
auto reader = vtkSmartPointer<vtkSTLReader>::New();
reader->SetFileName(fileName.c_str());
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".vtk")
{
auto reader = vtkSmartPointer<vtkPolyDataReader>::New();
reader->SetFileName(fileName.c_str());
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".g")
{
auto reader = vtkSmartPointer<vtkBYUReader>::New();
reader->SetGeometryFileName(fileName.c_str());
reader->Update();
polyData = reader->GetOutput();
}
else
{
// Return a polydata sphere if the extension is unknown.
auto source = vtkSmartPointer<vtkSphereSource>::New();
source->SetThetaResolution(20);
source->SetPhiResolution(11);
source->Update();
polyData = source->GetOutput();
}
return polyData;
}
} // namespace
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(SubdivisionDemo)
find_package(VTK COMPONENTS
vtkvtkCommonColor
vtkvtkCommonCore
vtkvtkCommonDataModel
vtkvtkFiltersCore
vtkvtkFiltersModeling
vtkvtkFiltersSources
vtkvtkIOGeometry
vtkvtkIOLegacy
vtkvtkIOPLY
vtkvtkIOXML
vtkvtkInteractionStyle
vtkvtkRenderingAnnotation
vtkvtkRenderingContextOpenGL2
vtkvtkRenderingCore
vtkvtkRenderingFreeType
vtkvtkRenderingGL2PSOpenGL2
vtkvtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
message("Skipping SubdivisionDemo: ${VTK_NOT_FOUND_MESSAGE}")
return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
# old system
include(${VTK_USE_FILE})
add_executable(SubdivisionDemo MACOSX_BUNDLE SubdivisionDemo.cxx )
target_link_libraries(SubdivisionDemo PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(SubdivisionDemo MACOSX_BUNDLE SubdivisionDemo.cxx )
target_link_libraries(SubdivisionDemo PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS SubdivisionDemo
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build SubdivisionDemo¶
Click here to download SubdivisionDemo and its CMakeLists.txt file. Once the tarball SubdivisionDemo.tar has been downloaded and extracted,
cd SubdivisionDemo/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:
./SubdivisionDemo
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.