The Opacity example is abnormal. When the Opacity is less than 1, the object disappears
Dear sir
Test example: https://kitware.github.io/vtk-examples/site/Cxx/Visualization/Opacity/ VTK 9.0.1 Windows10-x64
I only modified the 35 lines of the example, which is the part to adjust the transparency But when the transparency is less than 1, the object will disappear
Is there a problem with my writing? Or is the routine not suitable for this version of vtk9.0.1? Looking forward to your help
line 35: sphereActor->GetProperty()->SetOpacity(0.7);
line 35: sphereActor->GetProperty()->SetOpacity(1);
#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkCubeSource.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSphereSource.h>
int main(int, char*[])
{
vtkNew<vtkNamedColors> colors;
// Cube
vtkNew<vtkCubeSource> cubeSource;
vtkNew<vtkPolyDataMapper> cubeMapper;
cubeMapper->SetInputConnection(cubeSource->GetOutputPort());
vtkNew<vtkActor> cubeActor;
cubeActor->GetProperty()->SetOpacity(0.5);
cubeActor->SetMapper(cubeMapper);
cubeActor->GetProperty()->SetColor(colors->GetColor3d("MistyRose").GetData());
// Sphere
vtkNew<vtkSphereSource> sphereSource;
vtkNew<vtkPolyDataMapper> sphereMapper;
sphereMapper->SetInputConnection(sphereSource->GetOutputPort());
vtkNew<vtkActor> sphereActor;
sphereActor->GetProperty()->SetColor(
colors->GetColor3d("LightGreen").GetData());
sphereActor->GetProperty()->SetOpacity(0.7);
sphereActor->SetMapper(sphereMapper);
// Create renderers and add actors of plane and cube
vtkNew<vtkRenderer> renderer;
renderer->AddActor(cubeActor);
renderer->AddActor(sphereActor);
// Add renderer to renderwindow and render
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->AddRenderer(renderer);
renderWindow->SetWindowName("Opacity");
renderer->SetBackground(colors->GetColor3d("DimGray").GetData());
renderWindow->Render();
renderer->GetActiveCamera()->Azimuth(-22.5);
renderer->GetActiveCamera()->Elevation(30);
vtkNew<vtkRenderWindowInteractor> interactor;
interactor->SetRenderWindow(renderWindow);
renderWindow->Render();
interactor->Start();
return EXIT_SUCCESS;
}
Edited by Mathieu Westphal (Kitware)