VTK/Examples/Cxx/PolyData/TriangleColoredPoints
From KitwarePublic
This example shows how by adding a color to each vertex of a triangle, the triangle's color will be smoothly varying between the colors of the vertices.
Contents
TriangleColoredPoints.cxx
#include <vtkVersion.h>
#include <vtkSmartPointer.h>
#include <vtkPoints.h>
#include <vtkXMLPolyDataWriter.h>
#include <vtkPolyData.h>
#include <vtkPointData.h>
#include <vtkCellArray.h>
#include <vtkTriangle.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
// For compatibility with new VTK generic data arrays
#ifdef vtkGenericDataArray_h
#define InsertNextTupleValue InsertNextTypedTuple
#endif
int main(int, char *[])
{
// Setup points
vtkSmartPointer<vtkPoints> points =
vtkSmartPointer<vtkPoints>::New();
points->InsertNextPoint(1.0, 0.0, 0.0);
points->InsertNextPoint(0.0, 0.0, 0.0);
points->InsertNextPoint(0.0, 1.0, 0.0);
// Define some colors
unsigned char red[3] = {255, 0, 0};
unsigned char green[3] = {0, 255, 0};
unsigned char blue[3] = {0, 0, 255};
// Setup the colors array
vtkSmartPointer<vtkUnsignedCharArray> colors =
vtkSmartPointer<vtkUnsignedCharArray>::New();
colors->SetNumberOfComponents(3);
colors->SetName("Colors");
// Add the three colors we have created to the array
colors->InsertNextTupleValue(red);
colors->InsertNextTupleValue(green);
colors->InsertNextTupleValue(blue);
// Create a triangle
vtkSmartPointer<vtkCellArray> triangles =
vtkSmartPointer<vtkCellArray>::New();
vtkSmartPointer<vtkTriangle> triangle =
vtkSmartPointer<vtkTriangle>::New();
triangle->GetPointIds()->SetId(0, 0);
triangle->GetPointIds()->SetId(1, 1);
triangle->GetPointIds()->SetId(2, 2);
triangles->InsertNextCell(triangle);
// Create a polydata object and add everything to it
vtkSmartPointer<vtkPolyData> polydata =
vtkSmartPointer<vtkPolyData>::New();
polydata->SetPoints(points);
polydata->SetPolys(triangles);
polydata->GetPointData()->SetScalars(colors);
// Visualize
vtkSmartPointer<vtkPolyDataMapper> mapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
#if VTK_MAJOR_VERSION <= 5
mapper->SetInputConnection(polydata->GetProducerPort());
#else
mapper->SetInputData(polydata);
#endif
vtkSmartPointer<vtkActor> actor =
vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
renderer->AddActor(actor);
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
Please try the new VTKExamples website.
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(TriangleColoredPoints)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(TriangleColoredPoints MACOSX_BUNDLE TriangleColoredPoints.cxx)
if(VTK_LIBRARIES)
target_link_libraries(TriangleColoredPoints ${VTK_LIBRARIES})
else()
target_link_libraries(TriangleColoredPoints vtkHybrid vtkWidgets)
endif()
Download and Build TriangleColoredPoints
Click here to download TriangleColoredPoints. and its CMakeLists.txt file.
Once the tarball TriangleColoredPoints.tar has been downloaded and extracted,
cd TriangleColoredPoints/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:
./TriangleColoredPoints
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.