Hi,
I’m beginner. I read tutorial and watch examples but some basic questions still actual.
So here is simple example of vtkStructuredGrid
. I’m trying to add data to the points and display this data as color. The problem that this modified example doesn’t work. As a result my displayed data is the same as in the picture from the example link. Please, give me a hint what I’am doing wrong?
Here is my modified code:
#include <vtkSmartPointer.h>
#include <vtkStructuredGrid.h>
#include <vtkXMLStructuredGridWriter.h>
#include <vtkDataSetMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkDoubleArray.h>
#include <vtkFloatArray.h>
#include <vtkLookupTable.h>
#include <vtkScalarBarActor.h>
#include <vtkPointData.h>
int main(int, char *[])
{
// Create a grid
vtkSmartPointer<vtkStructuredGrid> structuredGrid =
vtkSmartPointer<vtkStructuredGrid>::New();
vtkSmartPointer<vtkPoints> points =
vtkSmartPointer<vtkPoints>::New();
vtkDoubleArray *array = vtkDoubleArray::New();
size_t nx = 2, ny = 3, nz = 2;
double x, y, z;
x = 0.0;
y = 0.0;
z = 0.0;
for (size_t i = 0; i < nx*ny*nz; i++){
array->InsertNextValue(i);
}
for(unsigned int k = 0; k < nz; k++)
{
z += 2.0;
for(unsigned int j = 0; j < ny; j++)
{
y += 1.0;
for(unsigned int i = 0; i < nx; i++)
{
x += .5;
points->InsertNextPoint(x, y, z);
}
}
}
// Specify the dimensions of the grid
structuredGrid->SetDimensions(nx,ny,nz);
structuredGrid->SetPoints(points);
structuredGrid->GetPointData()->AddArray(array);
int* dims = structuredGrid->GetDimensions();
// Retrieve the entries from the grid and print them to the screen
unsigned int counter = 0;
for (int k = 0; k < dims[2]; k++)
{
for (int j = 0; j < dims[1]; j++)
{
for (int i = 0; i < dims[0]; i++)
{
double p[3];
structuredGrid->GetPoint(counter, p);
double pNew[3];
structuredGrid->GetPoint(i, j, k, pNew);
std::cout << "P : "
<< p[0] << " "
<< p[1] << " "
<< p[2] << std::endl;
std::cout << "PNew: "
<< pNew[0] << " "
<< pNew[1] << " "
<< pNew[2] << std::endl;
counter++;
}
}
}
// Map the scalar values in the image to colors with a lookup table:
vtkSmartPointer<vtkLookupTable> lookupTable =
vtkSmartPointer<vtkLookupTable>::New();
//lookupTable->SetRange(0.0, nx*ny*nz); // image intensity range
//lookupTable->SetValueRange(0.0, nx*ny*nz); // from black to white
lookupTable->SetTableRange(0, nx*ny*nz);
//lookupTable->SetSaturationRange(0.0, nx*ny*nz); // no color saturation
//lookupTable->SetNumberOfTableValues(256);
lookupTable->SetRampToLinear();
lookupTable->Build();
// Create a mapper and actor
vtkSmartPointer<vtkDataSetMapper> mapper =
vtkSmartPointer<vtkDataSetMapper>::New();
mapper->SetInputData(structuredGrid);
mapper->SetLookupTable(lookupTable);
vtkSmartPointer<vtkActor> actor =
vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
// Create a renderer, render window, and interactor
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
// Add the actor to the scene
renderer->AddActor(actor);
renderer->SetBackground(.3, .6, .3); // Background color green
// Render and interact
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
Best regards,
kerim