[Qt5.1 beta] OpenGL, white screen

Bilouse

Hi !

I am a complete beginner in OpenGL (Windows x64)

I used this example from KDAB :
http://www.kdab.com/opengl-in-qt-5-1-part-1/

The code is exactly the same, except a dynamic_cast on this line:
@m_funcs = m_context->versionFunctions()@

And whatever I do, I get a white window.

A @m_funcs->glClearColor(0.0f, 0.0f, 0.0f, 1.0f)@

is expected to show a black background, isn't it ? It's always a white background, nothing is displayed.

I also tested with a OpenGL 3.3 context.
My drivers are updated, there must be something I did not understand ...

(sorry, my English must be deplorable)

Thanks !

Skyrpex

Hi Bilouse,

you must perform some other calls in order to see something into the screen.

@m_context->makeCurrent( this ); // Make sure you make the context current
m_funcs->glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // Specify the color that glClear(...) will use
m_funcs->glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); // Actually, clear the window with the color mentioned above
m_context->swapBuffers( this ); // Send the data to the window
@

Edit: I recommend you to download the tesselation example at the bottom of the "5th Qt5.1 post at KDAB":http://www.kdab.com/opengl-in-qt-5-1-part-5/