Setting SphereGeometry pickable leads to QML crashing in QTquick3D

Vinny

Hi, I am pretty new to QML development so bear with me.

Versions:
Python 3.13.5
Pyside 6.9.1
QtQuick3D

Installed with pip

Platform: Windows11

Running the main Python program from terminal, but got the same issue running in QT creator 16.02.

I am trying to implement a pickable sphere into my application (for changing camera focus between objects on klick).
But I have so far run into a couple of problems working with spheres.

First I tried using the built in #Sphere source:

Model {
    
    id: test_sphere
    pickable: true
    property real a: 6378.137
    property real b: 6356.752314245
    
    source: "#Sphere"
    position: Qt.vector3d(0, 0, -13000)
    
    scale: Qt.vector3d(100, 100, 100)
    materials: PrincipledMaterial {
        
        metalness: 0
        roughness: 1    
        specularAmount: 0
        emissiveFactor: Qt.vector3d(1, 1, 1)
    }
}

This model loads and picking works as excpected. The problem is that I couldn't find how the scaling factor works. Idealy I would like to set the radius/diameter of the sphere directly which would make the scaling easy.

In the example using scale:

Qt.vector3d(100, 100, 100)

seems to just scale the sphere to an arbetrary size and I can't see how the numbers correspond to the envirenoment coordinates. I was not able to find any documentation on this either.

So searching for alternatives I found that I could define the sphere with geometry:

 geometry: SphereGeometry { radius: 1.0 }

This made scaling the sphere easy to work with, but when I set pickable to true, the program crashes when trying to load the sphere with error:

Windows fatal exception: access violation

So seems that there is something deeper in the QML/C++ not working.
Code:

Model {
    
    id: test_sphere
    pickable: true

    position: Qt.vector3d(0, 0, -13000)
    geometry: SphereGeometry { radius: 1.0 }
    scale: Qt.vector3d(100, 100, 100)

    materials: PrincipledMaterial {
        metalness: 0
        roughness: 1    
        specularAmount: 0
        emissiveFactor: Qt.vector3d(1, 1, 1)
    }
}

Is this a bug or is pickable simply not compatible when using geometry?

Alternatively if someone could explane to me the scaling factor of the built in #Sphere that would be great!

Jonas Karlsson

This sounds like a bug and I think you should report it to https://bugreports.qt.io/