Adapt a QML part to OpenGL abilities

YvesB

Hello,
I'm working on an application intended to be used only in Linux platform, but without specification about graphical configuration.
A user reported me a stop of the application because its graphical card is Intel 82852/855GM, thus without OpenGL 2 abilities. The error reported is:
QOpenGLShader: could not create shader
I presume this is because I use LinearGradient.
What I want to try is to detect if the platform is OpenGL2 able or not, and if not don't use LinearGradient.
I tried some log in Qml:
console.log(GraphicsInfo.majorVersion, GraphicsInfo.minorVersion)
but which reports me "undefined undefined"
Documentation about GraphicsInfo says: "If the item to which the properties are attached is not currently associated with any window, the properties are set to default values. "
I don't understand to which item and properties it is referred to.

Thanks

Nifiro

import QtQuick 2.12
import QtQuick.Controls 2.12

ApplicationWindow {
    visible: true

    MouseArea {
        anchors.fill: parent
        onClicked: console.log(GraphicsInfo.majorVersion, GraphicsInfo.minorVersion)
    }
}

YvesB

@Nifiro
Thanks,
Indeed, this is working with qmlscene.
Thus I have to find why this is not working for my application.
I have Qt 5.9, but I don't think this could be a problem.
I don't have QtQuick 2.12, but tried with QtQuick 2.8 and this works.
I tried also QtQuick.Controls 1.4 with no problem.
My application is launched from Python 3 using PyQt, QGuiApplication and QQuickView. When I replace the QML file with the one you provided and I replace ApplicationWindow with Rectangle, this works too. I get 3 and 0 respectively.
I have now included outputs for GraphicsInfo.majorVersion and minor, what I get is variable :/
One time, I get 3.0, another time, I get 2.0 (same application)
Why is this changing ? Is not this information about system ability?

YvesB

I continue my investigations.
I passed the test example from Nifiro to the guy who got the problems.
He got now:

QT_LOGGING_RULES=qml=true qmlscene test.qml
QOpenGLShader: could not create shader
Segmentation fault (core dumped)

Thus I presume that the error occurs before I can test the version (at import or at ApplicationWindow?), which is useless.
This says also that my first plan to adapt instructions in QML is void :/