Hi,

It's a little bit more complex than that. See this article about the various transformation that you can apply.

@jsulm There're no calls to paintEvent() or update() inside updateGL()

void OpenGLWidget::updateGL() { makeCurrent(); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); //LEQUAL glEnable(GL_CULL_FACE); glFrontFace(GL_CW); glLineWidth(1.0f); // glDisable(GL_DITHER); glEnable(GL_LINE_SMOOTH); glEnable(GL_MULTISAMPLE); glViewport(0,0,m_width , m_height); m_camera = m_cameraController.toMatrix(); QVector3D lightDirection; switch (m_currView) { case TopView: lightDirection = QVector3D(0.0,0.0,1.0); break; case BottomView: lightDirection = QVector3D(0.0,0.0,-1.0); break; case LeftView: lightDirection = QVector3D(-1.0,0.0,0.0); break; case RightView: lightDirection = QVector3D(1.0,0.0,0.0); break; case FrontView: lightDirection = QVector3D(0.0,-1.0,0.0); break; case BackView: lightDirection = QVector3D(0.0,1.0,0.0); break; } lightDirection.normalize(); QVector3D directionalColor = QVector3D(0.3,0.3,0.3); QVector3D ambientLight = QVector3D(0.5,0.5,0.5); m_world.setToIdentity(); m_world.translate(m_modelBox.getCenterPoint()); m_world.rotate(m_rotation); m_world.scale(1.0f, 1.0f, m_worldZScalar); m_world.translate(-m_modelBox.getCenterPoint()); QMatrix3x3 normalMatrix = m_world.normalMatrix(); if(geometries){ if(!m_drawWireFrame){ m_programGrid->bind(); //Set MVP Uniforms m_programGrid->setUniformValue(m_projMatrixLoc, m_proj); m_programGrid->setUniformValue(m_mvMatrixLoc, m_camera * m_world); m_programGrid->setUniformValue(m_normalMatrixLoc, normalMatrix); //Set Lighting Uniforms. m_programGrid->setUniformValue(m_lightDirectionLoc, lightDirection); m_programGrid->setUniformValue(m_directionalColorLoc, directionalColor); m_programGrid->setUniformValue(m_ambientColorLoc, ambientLight); //Draw Grid Geometry geometries->drawGeometry(m_programGrid); m_programGrid->release(); //Draw Border Lines if(m_showBorders){ m_programLines->bind(); m_programLines->setUniformValue(m_projMatrixLocLines, m_proj); m_programLines->setUniformValue(m_mvMatrixLocLines, m_camera * m_world); geometries->drawLines(m_programLines, QVector3D(0.0,0.0,0.0)); m_programLines->release(); } }else{ m_programLines->bind(); m_programLines->setUniformValue(m_projMatrixLocLines, m_proj); m_programLines->setUniformValue(m_mvMatrixLocLines, m_camera * m_world); geometries->drawLines(m_programLines, QVector3D(1.0,1.0,1.0)); m_programLines->release(); } } if(wellgeometries){ glLineWidth(4.0f); m_programLines->bind(); m_programLines->setUniformValue(m_projMatrixLocLines, m_proj); m_programLines->setUniformValue(m_mvMatrixLocLines, m_camera * m_world); wellgeometries->drawLines(m_programLines, QVector3D(1.0,0.0,0.0)); m_programLines->release(); } if(m_showCompass){ glDisable(GL_DEPTH_TEST); glViewport(0,0,100,100); m_world.setToIdentity(); m_world.translate(0,0,-5); m_world.rotate(m_cameraController.rotation().inverted()); m_world.rotate(m_rotation); QMatrix4x4 proj; // Set near plane, far plane , field of view const qreal zNear = 1.0f, zFar = 150.0f, fov = 45.0; proj.setToIdentity(); proj.perspective(fov, 1.0f, zNear, zFar); m_programGrid->bind(); m_programGrid->setUniformValue(m_projMatrixLoc, proj); m_programGrid->setUniformValue(m_mvMatrixLoc, m_world); m_programGrid->setUniformValue(m_normalMatrixLoc, normalMatrix); //Set Lighting Uniforms. m_programGrid->setUniformValue(m_lightDirectionLoc, lightDirection); m_programGrid->setUniformValue(m_directionalColorLoc, directionalColor); m_programGrid->setUniformValue(m_ambientColorLoc, ambientLight); compass->drawCompassGeometry(m_programGrid); m_programGrid->release(); } //doneCurrent(); }

QOpenGLWidget is works into an FBO. Probably the surface format was set to multisampled therefore the underlying FBO inherited that and reading GL_DEPTH_COMPONENT from a multisampled FBO is not possible. To check this set samlpes to zero in QSurfaceFormat and pass it to QOpenGLWidget.

There's no need to call makeCurrent() in the virtual GL methods. It's already done for you before they are called and doneCurrent() is called for you after they finish. See the docs for these methods.

Hello,
I know they don't inherit one another, that's why I'm asking if it's possible. :)
I have a form with QOpenGLWidget laid out and want to use Qt3D, which does require a QWindow subclass for its painting routines. Now I was thinking maybe creating an attached QOpenGLWindow and sharing contexts but I'm not quite sure if this is the way. Anyway, createWindowsContainer is a possible solution, but I'd need to handle the layout insertion manually, this is why I'm asking.

Kind regards.

Hi and welcome to devnet,

IIRC when you want to mix both, you need to enclose your OpenGL primitives call between painter-> beginNativePainting() and painter->endNativePainting()

Hope it helps

@yoavmil Thank you, that resolved the issue. I have now set it up in main to show and then immediately hide the main window. I connected the splash screen close slot to a custom signal indicating when the model has finished loading. So now the main window becomes visible upon the model loading and the splash screen persists until receiving the very same signal.

Can nobody help me out ?

Thanks Chris. That solves the problem.

Hi and welcome to devnet,

To discuss such matters, I'd recommend posting on the interest You'll find there Qt's developers/maintainers (This forum is more user oriented)

Hi,

It is a limitation.

http://doc.qt.io/qt-5/qopenglwidget.html

"Limitations
Putting other widgets underneath and making the QOpenGLWidget transparent will not lead to the expected results: The widgets underneath will not be visible. This is because in practice the QOpenGLWidget is drawn before all other regular, non-OpenGL widgets, and so see-through type of solutions are not feasible. Other type of layouts, like having widgets on top of the QOpenGLWidget, will function as expected."

You have to use Qt::WA_AlwaysStackOnTop to do this.

I have a small update on this:

If I call glFinish() after my rendering is done, then I can make it work right (given that I specified double-buffering, otherwise the colors appear way too bright).
The downside is that with glFinish(), the rendering takes 30% longer..