# ParametricObjectsDemo

VTKExamples/Cxx/Deprecated/GeometricObjects/ParametricObjectsDemo

### Description¶

See Parametric Equations for Surfaces by Andrew Maclean for an excellent description of these beautiful parametric surfaces.

This example also demonstrates how to manipulate lists of VTK objects using vectors. Notice how parameters of the various Parametric Objects are accessed and set in the parametricObjects vector.

Other Languages

See (Python)

Question

### Code¶

ParametricObjectsDemo.cxx

#include <vtkActor.h>
#include <vtkActor2D.h>
#include <vtkCamera.h>
#include <vtkMinimalStandardRandomSequence.h>
#include <vtkNamedColors.h>
#include <vtkParametricFunctionSource.h>
#include <vtkPoints.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkTextMapper.h>
#include <vtkTextProperty.h>

#include <vtkParametricBoy.h>
#include <vtkParametricConicSpiral.h>
#include <vtkParametricCrossCap.h>
#include <vtkParametricDini.h>
#include <vtkParametricEllipsoid.h>
#include <vtkParametricEnneper.h>
#include <vtkParametricFigure8Klein.h>
#include <vtkParametricKlein.h>
#include <vtkParametricMobius.h>
#include <vtkParametricRandomHills.h>
#include <vtkParametricRoman.h>
#include <vtkParametricSpline.h>
#include <vtkParametricSuperEllipsoid.h>
#include <vtkParametricSuperToroid.h>
#include <vtkParametricTorus.h>

#include <array>
#include <vector>

int main(int, char* [])
{
vtkSmartPointer<vtkNamedColors> colors =
vtkSmartPointer<vtkNamedColors>::New();

// Set the background color.
std::array<unsigned char , 4> bkg{{26, 51, 102, 255}};
colors->SetColor("BkgColor", bkg.data());

std::vector<vtkSmartPointer<vtkParametricFunction>> parametricObjects;
parametricObjects.push_back(vtkSmartPointer<vtkParametricBoy>::New());
parametricObjects.push_back(vtkSmartPointer<vtkParametricConicSpiral>::New());
parametricObjects.push_back(vtkSmartPointer<vtkParametricCrossCap>::New());
parametricObjects.push_back(vtkSmartPointer<vtkParametricDini>::New());

parametricObjects.push_back(vtkSmartPointer<vtkParametricEllipsoid>::New());
static_cast<vtkParametricEllipsoid*>(parametricObjects.back().GetPointer())
static_cast<vtkParametricEllipsoid*>(parametricObjects.back().GetPointer())

parametricObjects.push_back(vtkSmartPointer<vtkParametricEnneper>::New());
parametricObjects.push_back(
vtkSmartPointer<vtkParametricFigure8Klein>::New());
parametricObjects.push_back(vtkSmartPointer<vtkParametricKlein>::New());
parametricObjects.push_back(vtkSmartPointer<vtkParametricMobius>::New());
static_cast<vtkParametricMobius*>(parametricObjects.back().GetPointer())
static_cast<vtkParametricMobius*>(parametricObjects.back().GetPointer())
->SetMinimumV(-0.5);
static_cast<vtkParametricMobius*>(parametricObjects.back().GetPointer())
->SetMaximumV(0.5);

vtkSmartPointer<vtkParametricRandomHills> randomHills =
vtkSmartPointer<vtkParametricRandomHills>::New();
randomHills->AllowRandomGenerationOff();
parametricObjects.push_back(randomHills);

parametricObjects.push_back(vtkSmartPointer<vtkParametricRoman>::New());

parametricObjects.push_back(
vtkSmartPointer<vtkParametricSuperEllipsoid>::New());
static_cast<vtkParametricSuperEllipsoid*>(
parametricObjects.back().GetPointer())
->SetN1(.50);
static_cast<vtkParametricSuperEllipsoid*>(
parametricObjects.back().GetPointer())
->SetN2(.1);

parametricObjects.push_back(vtkSmartPointer<vtkParametricSuperToroid>::New());
static_cast<vtkParametricSuperToroid*>(parametricObjects.back().GetPointer())
->SetN1(.2);
static_cast<vtkParametricSuperToroid*>(parametricObjects.back().GetPointer())
->SetN2(3.0);

parametricObjects.push_back(vtkSmartPointer<vtkParametricTorus>::New());

// The spline needs points
vtkSmartPointer<vtkParametricSpline> spline =
vtkSmartPointer<vtkParametricSpline>::New();
vtkSmartPointer<vtkPoints> inputPoints = vtkSmartPointer<vtkPoints>::New();
vtkSmartPointer<vtkMinimalStandardRandomSequence> rng =
vtkSmartPointer<vtkMinimalStandardRandomSequence>::New();
rng->SetSeed(8775070); // For testing.
for (auto i = 0; i < 10; ++i)
{
rng->Next();
auto x = rng->GetRangeValue(0.0, 1.0);
rng->Next();
auto y = rng->GetRangeValue(0.0, 1.0);
rng->Next();
auto z = rng->GetRangeValue(0.0, 1.0);
inputPoints->InsertNextPoint(x, y, z);
}
spline->SetPoints(inputPoints);
parametricObjects.push_back(spline);

std::vector<vtkSmartPointer<vtkParametricFunctionSource>>
parametricFunctionSources;
std::vector<vtkSmartPointer<vtkRenderer>> renderers;
std::vector<vtkSmartPointer<vtkPolyDataMapper>> mappers;
std::vector<vtkSmartPointer<vtkActor>> actors;
std::vector<vtkSmartPointer<vtkTextMapper>> textmappers;
std::vector<vtkSmartPointer<vtkActor2D>> textactors;

// Create one text property for all
vtkSmartPointer<vtkTextProperty> textProperty =
vtkSmartPointer<vtkTextProperty>::New();
textProperty->SetFontSize(12);
textProperty->SetJustificationToCentered();

vtkSmartPointer<vtkProperty> backProperty =
vtkSmartPointer<vtkProperty>::New();
backProperty->SetColor(colors->GetColor3d("Tomato").GetData());

// Create a parametric function source, renderer, mapper, and actor
// for each object
for (auto i = 0; i < parametricObjects.size(); i++)
{
parametricFunctionSources.push_back(
vtkSmartPointer<vtkParametricFunctionSource>::New());
parametricFunctionSources[i]->SetParametricFunction(parametricObjects[i]);
parametricFunctionSources[i]->SetUResolution(51);
parametricFunctionSources[i]->SetVResolution(51);
parametricFunctionSources[i]->SetWResolution(51);
parametricFunctionSources[i]->Update();

mappers.push_back(vtkSmartPointer<vtkPolyDataMapper>::New());
mappers[i]->SetInputConnection(
parametricFunctionSources[i]->GetOutputPort());

actors.push_back(vtkSmartPointer<vtkActor>::New());
actors[i]->SetMapper(mappers[i]);
actors[i]->GetProperty()->SetColor(colors->GetColor3d("Banana").GetData());
actors[i]->GetProperty()->SetSpecular(.5);
actors[i]->GetProperty()->SetSpecularPower(20);
actors[i]->SetBackfaceProperty(backProperty);

textmappers.push_back(vtkSmartPointer<vtkTextMapper>::New());
textmappers[i]->SetInput(parametricObjects[i]->GetClassName());
textmappers[i]->SetTextProperty(textProperty);

textactors.push_back(vtkSmartPointer<vtkActor2D>::New());
textactors[i]->SetMapper(textmappers[i]);
textactors[i]->SetPosition(100, 16);

renderers.push_back(vtkSmartPointer<vtkRenderer>::New());
renderers[i]->SetBackground(colors->GetColor3d("BkgColor").GetData());
}

// Setup the viewports
auto xGridDimensions = 4;
auto yGridDimensions = 4;
auto rendererSize = 200;
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->SetWindowName("Parametric Objects Demonstration");
renderWindow->SetSize(rendererSize * xGridDimensions,
rendererSize * yGridDimensions);

for(auto row = 0; row < yGridDimensions; row++)
{
for(auto col = 0; col < xGridDimensions; col++)
{
int index = row * xGridDimensions + col;

// (xmin, ymin, xmax, ymax)
double viewport[4] = {
static_cast<double>(col) / xGridDimensions,
static_cast<double>(yGridDimensions - (row + 1))/ yGridDimensions,
static_cast<double>(col + 1) / xGridDimensions,
static_cast<double>(yGridDimensions - row) / yGridDimensions
};

if(index > int(actors.size()) - 1)
{
// Add a renderer even if there is no actor.
// This makes the render window background all the same color.
vtkSmartPointer<vtkRenderer> ren = vtkSmartPointer<vtkRenderer>::New();
ren->SetBackground(colors->GetColor3d("BkgColor").GetData());
ren->SetViewport(viewport);
continue;
}

renderers[index]->SetViewport(viewport);
renderers[index]->ResetCamera();
renderers[index]->GetActiveCamera()->Azimuth(30);
renderers[index]->GetActiveCamera()->Elevation(-30);
renderers[index]->ResetCameraClippingRange();
}
}

vtkSmartPointer<vtkRenderWindowInteractor> interactor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
interactor->SetRenderWindow(renderWindow);

renderWindow->Render();
interactor->Start();

return EXIT_SUCCESS;
}


### CMakeLists.txt¶

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(ParametricObjectsDemo)

find_package(VTK COMPONENTS
vtkCommonColor
vtkCommonComputationalGeometry
vtkCommonCore
vtkInteractionStyle
vtkRenderingContextOpenGL2
vtkRenderingCore
vtkRenderingFreeType
vtkRenderingGL2PSOpenGL2
vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
message("Skipping ParametricObjectsDemo: ${VTK_NOT_FOUND_MESSAGE}") return () endif() message (STATUS "VTK_VERSION:${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
# old system
include(${VTK_USE_FILE}) add_executable(ParametricObjectsDemo MACOSX_BUNDLE ParametricObjectsDemo.cxx ) target_link_libraries(ParametricObjectsDemo PRIVATE${VTK_LIBRARIES})
else ()
# include all components
target_link_libraries(ParametricObjectsDemo PRIVATE ${VTK_LIBRARIES}) # vtk_module_autoinit is needed vtk_module_autoinit( TARGETS ParametricObjectsDemo MODULES${VTK_LIBRARIES}
)
endif ()


cd ParametricObjectsDemo/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:

./ParametricObjectsDemo


WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.