VisualizeModifiedBSPTree
VTKEx/Cxx/DataStructures/VisualizeModifiedBSPTree
Description¶
This demo displays level of a vtkModifiedBSPTree using a slider. A Modified BSP Tree is a BSP Tree. It is used for rendering, collision detection, and point location.
Here is the embedded video:
Seealso
Question
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Code¶
VisualizeModifiedBSPTree.cxx
#include <vtkActor.h>
#include <vtkCallbackCommand.h>
#include <vtkCommand.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkMath.h>
#include <vtkModifiedBSPTree.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPointSource.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkProperty2D.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSliderRepresentation2D.h>
#include <vtkSliderWidget.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkTextProperty.h>
#include <vtkWidgetEvent.h>
#include <vtkWidgetEventTranslator.h>
#include <vtkBYUReader.h>
#include <vtkOBJReader.h>
#include <vtkPLYReader.h>
#include <vtkPolyDataReader.h>
#include <vtkSTLReader.h>
#include <vtkXMLPolyDataReader.h>
#include <vtksys/SystemTools.hxx>
#include <cmath>
namespace {
class vtkSliderCallback : public vtkCommand {
public:
static vtkSliderCallback *New() { return new vtkSliderCallback; }
vtkSliderCallback() : BSPTree(0), Level(0), PolyData(0), Renderer(0) {}
virtual void Execute(vtkObject *caller, unsigned long, void *) {
vtkSliderWidget *sliderWidget = reinterpret_cast<vtkSliderWidget *>(caller);
this->Level = vtkMath::Round(static_cast<vtkSliderRepresentation *>(
sliderWidget->GetRepresentation())
->GetValue());
this->BSPTree->GenerateRepresentation(this->Level, this->PolyData);
this->Renderer->Render();
}
vtkModifiedBSPTree *BSPTree;
int Level;
vtkPolyData *PolyData;
vtkRenderer *Renderer;
};
} // namespace
namespace
{
vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName);
}
int main(int argc, char *argv[]) {
vtkSmartPointer<vtkPolyData> polyData = ReadPolyData(argc > 1 ? argv[1] : "");;
auto colors =
vtkSmartPointer<vtkNamedColors>::New();
auto pointsMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
pointsMapper->SetInputData(polyData);
pointsMapper->ScalarVisibilityOff();
auto pointsActor = vtkSmartPointer<vtkActor>::New();
pointsActor->SetMapper(pointsMapper);
pointsActor->GetProperty()->SetInterpolationToFlat();
pointsActor->GetProperty()->SetOpacity(.3);
pointsActor->GetProperty()->SetColor(colors->GetColor4d("Yellow").GetData());
// Create the tree
auto bspTree =
vtkSmartPointer<vtkModifiedBSPTree>::New();
bspTree->SetDataSet(polyData);
bspTree->BuildLocator();
int maxLevel = 5;
// Initialize the representation
auto polydata = vtkSmartPointer<vtkPolyData>::New();
bspTree->SetMaxLevel(maxLevel);
bspTree->GenerateRepresentation(0, polydata);
auto bspTreeMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
bspTreeMapper->SetInputData(polydata);
auto bspTreeActor = vtkSmartPointer<vtkActor>::New();
bspTreeActor->SetMapper(bspTreeMapper);
bspTreeActor->GetProperty()->SetInterpolationToFlat();
bspTreeActor->GetProperty()->SetOpacity(.5);
bspTreeActor->GetProperty()->EdgeVisibilityOn();
bspTreeActor->GetProperty()->SetColor(
colors->GetColor4d("SpringGreen").GetData());
// A renderer and render window
auto renderer = vtkSmartPointer<vtkRenderer>::New();
auto renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
// An interactor
auto style =
vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();
auto renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
renderWindowInteractor->SetInteractorStyle(style);
// Add the actors to the scene
renderer->AddActor(pointsActor);
renderer->AddActor(bspTreeActor);
renderer->SetBackground(colors->GetColor3d("SteelBLue").GetData());
renderer->UseHiddenLineRemovalOn();
// Render an image (lights and cameras are created automatically)
renderWindow->SetWindowName("VisualizeModifiedBSPTree");
renderWindow->SetSize(600, 600);
renderWindow->Render();
auto sliderRep =
vtkSmartPointer<vtkSliderRepresentation2D>::New();
sliderRep->SetMinimumValue(0);
sliderRep->SetMaximumValue(bspTree->GetLevel());
sliderRep->SetValue(bspTree->GetLevel() / 2);
sliderRep->SetTitleText("Level");
sliderRep->GetPoint1Coordinate()->SetCoordinateSystemToNormalizedDisplay();
sliderRep->GetPoint1Coordinate()->SetValue(.2, .2);
sliderRep->GetPoint2Coordinate()->SetCoordinateSystemToNormalizedDisplay();
sliderRep->GetPoint2Coordinate()->SetValue(.8, .2);
sliderRep->SetSliderLength(0.075);
sliderRep->SetSliderWidth(0.05);
sliderRep->SetEndCapLength(0.05);
sliderRep->GetTitleProperty()->SetColor(
colors->GetColor3d("Beige").GetData());
sliderRep->GetCapProperty()->SetColor(
colors->GetColor3d("MistyRose").GetData());
sliderRep->GetSliderProperty()->SetColor(
colors->GetColor3d("LightBlue").GetData());
sliderRep->GetSelectedProperty()->SetColor(
colors->GetColor3d("Violet").GetData());
auto sliderWidget =
vtkSmartPointer<vtkSliderWidget>::New();
sliderWidget->SetInteractor(renderWindowInteractor);
sliderWidget->SetRepresentation(sliderRep);
sliderWidget->SetAnimationModeToAnimate();
sliderWidget->EnabledOn();
auto callback =
vtkSmartPointer<vtkSliderCallback>::New();
callback->BSPTree = bspTree;
callback->PolyData = polydata;
callback->Renderer = renderer;
callback->Execute(sliderWidget, 0, 0);
sliderWidget->AddObserver(vtkCommand::InteractionEvent, callback);
renderWindowInteractor->Initialize();
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
namespace
{
vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName)
{
vtkSmartPointer<vtkPolyData> polyData;
std::string extension = vtksys::SystemTools::GetFilenameLastExtension(std::string(fileName));
if (extension == ".ply")
{
auto reader =
vtkSmartPointer<vtkPLYReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".vtp")
{
auto reader =
vtkSmartPointer<vtkXMLPolyDataReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".obj")
{
auto reader =
vtkSmartPointer<vtkOBJReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".stl")
{
auto reader =
vtkSmartPointer<vtkSTLReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".vtk")
{
auto reader =
vtkSmartPointer<vtkPolyDataReader>::New();
reader->SetFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else if (extension == ".g")
{
auto reader =
vtkSmartPointer<vtkBYUReader>::New();
reader->SetGeometryFileName (fileName);
reader->Update();
polyData = reader->GetOutput();
}
else
{
vtkSmartPointer<vtkSphereSource> source =
vtkSmartPointer<vtkSphereSource>::New();
source->Update();
polyData = source->GetOutput();
}
return polyData;
}
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(VisualizeModifiedBSPTree)
find_package(VTK COMPONENTS
vtkvtkCommonColor
vtkvtkCommonCore
vtkvtkCommonDataModel
vtkvtkFiltersFlowPaths
vtkvtkFiltersSources
vtkvtkIOGeometry
vtkvtkIOLegacy
vtkvtkIOPLY
vtkvtkIOXML
vtkvtkInteractionStyle
vtkvtkInteractionWidgets
vtkvtkRenderingContextOpenGL2
vtkvtkRenderingCore
vtkvtkRenderingFreeType
vtkvtkRenderingGL2PSOpenGL2
vtkvtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
message("Skipping VisualizeModifiedBSPTree: ${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(VisualizeModifiedBSPTree MACOSX_BUNDLE VisualizeModifiedBSPTree.cxx )
target_link_libraries(VisualizeModifiedBSPTree PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(VisualizeModifiedBSPTree MACOSX_BUNDLE VisualizeModifiedBSPTree.cxx )
target_link_libraries(VisualizeModifiedBSPTree PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS VisualizeModifiedBSPTree
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build VisualizeModifiedBSPTree¶
Click here to download VisualizeModifiedBSPTree and its CMakeLists.txt file. Once the tarball VisualizeModifiedBSPTree.tar has been downloaded and extracted,
cd VisualizeModifiedBSPTree/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:
./VisualizeModifiedBSPTree
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.