# qvtk rendering

**URL:** <https://discourse.vtk.org/t/qvtk-rendering/11432>\
**Category:** Development\
**Created:** [May 11, 2023, 9:14am UTC](https://discourse.vtk.org/t/qvtk-rendering/11432 "2023-05-11T09:14:53Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![ubed20](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/u/c4cdca/32.png) [@ubed20](https://discourse.vtk.org/u/ubed20)\
**Post date:** [May 11, 2023, 9:14am UTC](https://discourse.vtk.org/t/qvtk-rendering/11432/1 "2023-05-11T09:14:54Z")

</div>

i am rendering change detection using point clouds data using vtk actors in QT GUI but i cannot interact with the window i can just load the data for change detection. i cannot zoom or rotate the point clouds and render the changed point clouds in the widow.  
vtkSmartPointer UprightRenderer = vtkSmartPointer::New();  
UprightRenderer-\>UseDepthPeelingOn();  
UprightRenderer-\>GradientBackgroundOn();  
UprightRenderer-\>SetBackground(0, 0, 0); // Background 2 color black  
UprightRenderer-\>SetBackground2(1, 1, 1); // Background color white  
UprightRenderer-\>AddActor(vtk\_PC\_Actor2);  
UprightRenderer-\>ResetCamera();

```
vtkSmartPointer<vtkGenericOpenGLRenderWindow> renderWindowRight = vtkSmartPointer<vtkGenericOpenGLRenderWindow>::New();
renderWindowRight->AddRenderer(UprightRenderer);

ui->UpRightWidget->SetRenderWindow(renderWindowRight);
ui->UpRightWidget->GetRenderWindow()->GetRenderers()->GetFirstRenderer()->SetActiveCamera(ui->UpLeftWidget->GetRenderWindow()->GetRenderers()->GetFirstRenderer()->GetActiveCamera());
ui->UpRightWidget->GetRenderWindow()->AddObserver(vtkCommand::RenderEvent, this, &PCLViewer::ModifiedHandlerSx);
ui->UpRightWidget->GetRenderWindow()->GetRenderers()->GetFirstRenderer()->Render();
ui->UpRightWidget->GetRenderWindow()->GetInteractor()->Render();
ui->UpRightWidget->GetRenderWindow()->Render();
ui->UpRightWidget->update();

```

here how pass the actor to render in the window. i am getting this stack trace on the terminal.  
Generic Warning: In /home/sentech/lib/VTK-8.2.0/Rendering/OpenGL2/vtkOpenGLState.cxx, line 162  
Error in cache state for GL\_VIEWPORT

Generic Warning: In /home/sentech/lib/VTK-8.2.0/Rendering/OpenGL2/vtkOpenGLState.cxx, line 173  
Error in cache state for GL\_SCISSOR\_BOX

Generic Warning: In /home/sentech/lib/VTK-8.2.0/Rendering/OpenGL2/vtkOpenGLState.cxx, line 229  
at stack loc  
0x7f27ea8099ea : vtksys::SystemInformationImplementation::GetProgramStack[abi:cxx11](int, int) [(libvtksys-8.2.so.1) ???:-1]  
0x7f27ea80456d : vtksys::SystemInformation::GetProgramStack[abi:cxx11](int, int) [(libvtksys-8.2.so.1) ???:-1]  
0x7f27f08fba35 : vtkOpenGLState::CheckState() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f08fd27a : vtkOpenGLState::vtkglViewport(int, int, int, int) [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f081ed51 : vtkOpenGLCamera::Render(vtkRenderer\*) [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f0513bb2 : vtkRenderer::UpdateCamera() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f08e176b : vtkOpenGLRenderer::DeviceRender() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f0513386 : vtkRenderer::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f0510794 : vtkRendererCollection::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f052e9e3 : vtkRenderWindow::DoStereoRender() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f052e797 : vtkRenderWindow::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f08dd4b4 : vtkOpenGLRenderWindow::Render() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f09a9dba : vtkXOpenGLRenderWindow::Render() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f053b892 : vtkRenderWindowInteractor::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f5672643 : QVTKWidget::doDeferredRender() [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f5671a81 : QVTKWidget::paintEvent(QPaintEvent\*) [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f511f2b6 : QWidget::event(QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5671789 : QVTKWidget::event(QEvent\*) [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f50dca66 : QApplicationPrivate::notify\_helper(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f50e60f0 : QApplication::notify(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f46c480a : QCoreApplication::notifyInternal2(QObject\*, QEvent\*) [(libQt5Core.so.5) ???:-1]  
0x7f27f5117f4a : QWidgetPrivate::sendPaintEvent(QRegion const&) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5118799 : QWidgetPrivate::drawWidget(QPaintDevice\*, QRegion const&, QPoint const&, int, QPainter\*, QWidgetBackingStore\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f50ed09d : QWidgetPrivate::repaint\_sys(QRegion const&) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5107318 : QWidgetPrivate::syncBackingStore() [(libQt5Widgets.so.5) ???:-1]  
0x7f27f511fcac : QWidget::event(QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5671789 : QVTKWidget::event(QEvent\*) [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f50dca66 : QApplicationPrivate::notify\_helper(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f50e60f0 : QApplication::notify(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f46c480a : QCoreApplication::notifyInternal2(QObject\*, QEvent\*) [(libQt5Core.so.5) ???:-1]  
0x7f27f46c7488 : QCoreApplicationPrivate::sendPostedEvents(QObject\*, int, QThreadData\*) [(libQt5Core.so.5) ???:-1]  
0x7f27f471ce37 : ??? [(???) ???:-1]  
0x7f27eb25617d : g\_main\_context\_dispatch [(libglib-2.0.so.0) ???:-1]  
0x7f27eb256400 : ??? [(???) ???:-1]  
0x7f27eb2564a3 : g\_main\_context\_iteration [(libglib-2.0.so.0) ???:-1]  
0x7f27f471c435 : QEventDispatcherGlib::processEvents(QFlagsQEventLoop::ProcessEventsFlag) [(libQt5Core.so.5) ???:-1]  
0x7f27f46c33ab : QEventLoop::exec(QFlagsQEventLoop::ProcessEventsFlag) [(libQt5Core.so.5) ???:-1]  
0x7f27f46cb116 : QCoreApplication::exec() [(libQt5Core.so.5) ???:-1]  
0x56491b122d9c : main [(RC\_EDS) ???:-1]  
0x7f27edd41083 : \_\_libc\_start\_main [(libc.so.6) ???:-1]  
0x56491b0f6f3e : \_start [(RC\_EDS) ???:-1]

Generic Warning: In /home/sentech/lib/VTK-8.2.0/Rendering/OpenGL2/vtkOpenGLState.cxx, line 173  
Error in cache state for GL\_SCISSOR\_BOX

Generic Warning: In /home/sentech/lib/VTK-8.2.0/Rendering/OpenGL2/vtkOpenGLState.cxx, line 229  
at stack loc  
0x7f27ea8099ea : vtksys::SystemInformationImplementation::GetProgramStack[abi:cxx11](int, int) [(libvtksys-8.2.so.1) ???:-1]  
0x7f27ea80456d : vtksys::SystemInformation::GetProgramStack[abi:cxx11](int, int) [(libvtksys-8.2.so.1) ???:-1]  
0x7f27f08fba35 : vtkOpenGLState::CheckState() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f08fd730 : vtkOpenGLState::SetEnumState(unsigned int, bool) [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f08fdb51 : vtkOpenGLState::vtkglEnable(unsigned int) [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f081ed65 : vtkOpenGLCamera::Render(vtkRenderer\*) [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f0513bb2 : vtkRenderer::UpdateCamera() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f08e176b : vtkOpenGLRenderer::DeviceRender() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f0513386 : vtkRenderer::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f0510794 : vtkRendererCollection::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f052e9e3 : vtkRenderWindow::DoStereoRender() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f052e797 : vtkRenderWindow::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f08dd4b4 : vtkOpenGLRenderWindow::Render() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f09a9dba : vtkXOpenGLRenderWindow::Render() [(libvtkRenderingOpenGL2-8.2.so.1) ???:-1]  
0x7f27f053b892 : vtkRenderWindowInteractor::Render() [(libvtkRenderingCore-8.2.so.1) ???:-1]  
0x7f27f5672643 : QVTKWidget::doDeferredRender() [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f5671a81 : QVTKWidget::paintEvent(QPaintEvent\*) [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f511f2b6 : QWidget::event(QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5671789 : QVTKWidget::event(QEvent\*) [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f50dca66 : QApplicationPrivate::notify\_helper(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f50e60f0 : QApplication::notify(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f46c480a : QCoreApplication::notifyInternal2(QObject\*, QEvent\*) [(libQt5Core.so.5) ???:-1]  
0x7f27f5117f4a : QWidgetPrivate::sendPaintEvent(QRegion const&) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5118799 : QWidgetPrivate::drawWidget(QPaintDevice\*, QRegion const&, QPoint const&, int, QPainter\*, QWidgetBackingStore\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f50ed09d : QWidgetPrivate::repaint\_sys(QRegion const&) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5107318 : QWidgetPrivate::syncBackingStore() [(libQt5Widgets.so.5) ???:-1]  
0x7f27f511fcac : QWidget::event(QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f5671789 : QVTKWidget::event(QEvent\*) [(libvtkGUISupportQt-8.2.so.1) ???:-1]  
0x7f27f50dca66 : QApplicationPrivate::notify\_helper(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f50e60f0 : QApplication::notify(QObject\*, QEvent\*) [(libQt5Widgets.so.5) ???:-1]  
0x7f27f46c480a : QCoreApplication::notifyInternal2(QObject\*, QEvent\*) [(libQt5Core.so.5) ???:-1]  
0x7f27f46c7488 : QCoreApplicationPrivate::sendPostedEvents(QObject\*, int, QThreadData\*) [(libQt5Core.so.5) ???:-1]  
0x7f27f471ce37 : ??? [(???) ???:-1]  
0x7f27eb25617d : g\_main\_context\_dispatch [(libglib-2.0.so.0) ???:-1]  
0x7f27eb256400 : ??? [(???) ???:-1]  
0x7f27eb2564a3 : g\_main\_context\_iteration [(libglib-2.0.so.0) ???:-1]  
0x7f27f471c435 : QEventDispatcherGlib::processEvents(QFlagsQEventLoop::ProcessEventsFlag) [(libQt5Core.so.5) ???:-1]  
0x7f27f46c33ab : QEventLoop::exec(QFlagsQEventLoop::ProcessEventsFlag) [(libQt5Core.so.5) ???:-1]  
0x7f27f46cb116 : QCoreApplication::exec() [(libQt5Core.so.5) ???:-1]  
0x56491b122d9c : main [(RC\_EDS) ???:-1]  
0x7f27edd41083 : \_\_libc\_start\_main [(libc.so.6) ???:-1]  
0x56491b0f6f3e : \_start [(RC\_EDS) ???:-1].