[visualization] Qt 6.9 and VTK 9.5 do not work with PCL on macos #6317
Description
I am trying to render PCLVisualizer into a Qt widget, something that has worked with qt5 and vtk 9.0 before. Since upgrading everything to Qt6, this either no longer works properly (all mouse movements are interpreted as if the left button was clicked, even though it is not, making the widget unusable) or crashes inside VTK in different places.
In trying to narrow down the issue (so far unsuccessfully), I am working with latest VTK master, and latest PCL master, and qt 6.9.1 from homebrew.
I am trying to run the qt_visualizer tutorial, and launching the program first prints some VTK warnings
2025-08-11 15:54:09.570 ( 0.541s) [ 5701D9] vtkOpenGLState.cxx:867 WARN| Error glBlendFuncSeparate1 OpenGL errors detected
0 : (1280) Invalid enum
with stack trace of
0x104b57170 : vtksys::SystemInformationImplementation::GetProgramStack(int, int) [(libvtksys-9.5.9.5.dylib) ???:-1]
0x104b570f0 : vtksys::SystemInformation::GetProgramStack(int, int) [(libvtksys-9.5.9.5.dylib) ???:-1]
0x106ae3384 : (anonymous namespace)::reportOpenGLErrors(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>&) [(libvtkRenderingOpenGL2-9.5.9.5.dylib) ???:-1]
0x106ae6424 : vtkOpenGLState::vtkglBlendFuncSeparate(unsigned int, unsigned int, unsigned int, unsigned int) [(libvtkRenderingOpenGL2-9.5.9.5.dylib) ???:-1]
0x106aaab58 : vtkOpenGLRenderWindow::Start() [(libvtkRenderingOpenGL2-9.5.9.5.dylib) ???:-1]
0x107a3f918 : vtkRenderWindow::Render() [(libvtkRenderingCore-9.5.9.5.dylib) ???:-1]
0x106aae54c : vtkOpenGLRenderWindow::Render() [(libvtkRenderingOpenGL2-9.5.9.5.dylib) ???:-1]
0x106903cd0 : vtkGenericOpenGLRenderWindow::Render() [(libvtkRenderingOpenGL2-9.5.9.5.dylib) ???:-1]
0x107a4bd48 : vtkRenderWindowInteractor::Render() [(libvtkRenderingCore-9.5.9.5.dylib) ???:-1]
0x10199aa5c : QVTKRenderWindowAdapter::QVTKInternals::paint() [(libvtkGUISupportQt-9.5.9.5.dylib) ???:-1]
0x10199a6f8 : QVTKRenderWindowAdapter::paint() [(libvtkGUISupportQt-9.5.9.5.dylib) ???:-1]
0x101995f28 : QVTKOpenGLNativeWidget::paintGL() [(libvtkGUISupportQt-9.5.9.5.dylib) ???:-1]
0x10052d62c : QOpenGLWidgetPrivate::render() [(QtOpenGLWidgets) ???:-1]
0x109591384 : QWidget::event(QEvent*) [(QtWidgets) ???:-1]
0x10052e608 : QOpenGLWidget::event(QEvent*) [(QtOpenGLWidgets) ???:-1]
0x101996270 : QVTKOpenGLNativeWidget::event(QEvent*) [(libvtkGUISupportQt-9.5.9.5.dylib) ???:-1]
…
And then crashes with SIGSEGV
error: memory read failed for 0x0
with such a backtrace
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
* frame #0: 0x0000000000000000
frame #1: 0x0000000106b16d40 libvtkRenderingOpenGL2-9.5.1.dylib`vtkOpenGLVertexArrayObject::Private::Initialize(this=0x0000600000f00750) at vtkOpenGLVertexArrayObject.cxx:90:7
frame #2: 0x0000000106b16918 libvtkRenderingOpenGL2-9.5.1.dylib`vtkOpenGLVertexArrayObject::Bind(this=0x000060000228afd0) at vtkOpenGLVertexArrayObject.cxx:147:21
frame #3: 0x0000000106a5a184 libvtkRenderingOpenGL2-9.5.1.dylib`vtkOpenGLPolyDataMapper::UpdateShaders(this=0x00000001448a2200, cellBO=0x00000001448a2438, ren=0x0000000144836000, actor=0x0000000143f36470) at vtkOpenGLPolyDataMapper.cxx:2623:15
frame #4: 0x0000000106a61d10 libvtkRenderingOpenGL2-9.5.1.dylib`vtkOpenGLPolyDataMapper::RenderPieceDraw(this=0x00000001448a2200, ren=0x0000000144836000, actor=0x0000000143f36470) at vtkOpenGLPolyDataMapper.cxx:3517:13
frame #5: 0x0000000106a62574 libvtkRenderingOpenGL2-9.5.1.dylib`vtkOpenGLPolyDataMapper::RenderPiece(this=0x00000001448a2200, ren=0x0000000144836000, actor=0x0000000143f36470) at vtkOpenGLPolyDataMapper.cxx:3656:9
frame #6: 0x0000000107a12080 libvtkRenderingCore-9.5.1.dylib`vtkPolyDataMapper::Render(this=0x00000001448a2200, ren=0x0000000144836000, act=0x0000000143f36470) at vtkPolyDataMapper.cxx:69:11
…
The trace points to this VTK code
class vtkOpenGLVertexArrayObject::Private
{
public:
Private()
{
this->HandleVAO = 0;
this->HandleProgram = 0;
this->Supported = true;
this->ForceEmulation = false;
}
~Private()
{
if (this->HandleVAO)
{
glDeleteVertexArrays(1, &this->HandleVAO);
}
}
void Initialize()
{
if (!this->ForceEmulation)
{
this->Supported = true;
glGenVertexArrays(1, &this->HandleVAO); // <----- CRASH
}
else
{
this->Supported = false;
}
}
Context
Restore embedded pcl visualizer functionality with recent qt and vtk on macos. I'm fully at a loss how to debug this, it also may not be a PCL issue at all, but a VTK problem.
Expected behavior
Pcl visualizer window embedded in qvtkopenglnativewidget
Current Behavior
Crash
To Reproduce
Try to build qt_visualizer tutorial against qt 6.9, VTK d3dba86dd6d189df0dd4fcfa1311eb814cf2a461 (current master) and PCL 11ed9cc (current master)
Screenshots/Code snippets
n/a
Your Environment (please complete the following information):
- OS: macOs 15.5 (24F74)
- Compiler: apple Clang
- PCL Version HEAD
Possible Solution
n/a
Additional context
n/a