[solved] How to create OpenGL 3.3 Context with QQuickView?

Bugtracker

How can I create and use my own OpenGL 3.3 Context with QQuickView?

I will paint a scene and using modern OpenGL functions. (like context 3.3 or 4.4)
I will paint either on the QQuickView window background or in a QQuickItem.

agocs

Via setFormat().

QSurfaceFormat format;
format.setVersion(3, 3);
format.setProfile(QSurfaceFormat::CoreProfile);
format.setDepthBufferSize(24);
format.setStencilBufferSize(8);
QQuickView view;
view.setFormat(format);
...

Bugtracker

I have changed the Qt example "openglunderqml"

@int main(int argc, char **argv)
{
QGuiApplication app(argc, argv);

qmlRegisterType<Squircle>("OpenGLUnderQML", 1, 0, "Squircle");

QSurfaceFormat format;
format.setVersion(3, 3);
format.setProfile&#40;QSurfaceFormat::CoreProfile&#41;;
format.setDepthBufferSize(24);
format.setStencilBufferSize(8);
QQuickView view;
view.setFormat(format);
view.setResizeMode(QQuickView::SizeRootObjectToView);
view.setSource(QUrl("qrc:///scenegraph/openglunderqml/main.qml"));
view.show();

return app.exec();

}@

The first error after start this is:

@QOpenGLShader::compile(Vertex): Vertex shader failed to compile with the following errors:
ERROR: error(#272) Implicit version number 110 not supported by GL3 forward compatible context@

I changed now in squircle.cppthe two addShaderFromSourceCode functions by adding "#version 330\n":
@
void SquircleRenderer::paint()
{
...
m_program->addShaderFromSourceCode(... ,
"#version 330\n"
"attribute highp vec4 vertices;"
...
...
...
);
m_program->addShaderFromSourceCode(... ,
"#version 330\n"
"uniform lowp float t;"
...
...
...
);
...
}
@

The result is a black background (not the pulsing colored) with the normal QML text element over it.

Have I forgot something? (eg. #include<...>)
When yes, what?

agocs

That's not a valid version 330 shader. There is no attribute keyword there. Try:

#version 330
in vec4 vertices;
...

Also, watch out for the fact that you are now using core profile so thinsg like mandatory usage of vertex array objects, no client-side pointers, etc. will all apply.

Bugtracker

Thanks, so only change the shader code is not enough for the example.

I'm porting a Qt 5.1 Project to Qt 5.3.1 and whould use a CompatibilityProfile.

In the "openglunderqml" example, using a CompatibilityProfile instead of CoreProfile result in crash the ATI driver in function
@atio6axx!DrvPresentBuffers
@

Is it allowed to use a CompatibilityProfile with setFormat()?

Bugtracker

I think I have found the answer.

@format.setOption(QSurfaceFormat::DeprecatedFunctions);
@

You have posted the solution at:
http://qt-project.org/forums/viewthread/42842/#177608

A tip in the documentation of QOpenGLContext would be helpfull.
Like AMD drivers make this necessary.

I have wasted one week of work for one line of code :)

ZapB

That is AMD specific and we can't possibly document all vendor or driver-version specific idiosyncrasies in the Qt docuemntation. I'm pretty sure it works fine on nVidia without the DeprecatedFunctions option (or maybe I'm thinking of Core profile).