The QOpenGLContext class represents a native OpenGL context, enabling OpenGL rendering on a QSurface.

QOpenGLContext represents the OpenGL state of an underlying OpenGL context. To set up a context, set its screen and format such that they match those of the surface or surfaces with which the context is meant to be used, if necessary make it share resources with other contexts with setShareContext(), and finally call create(). Use the return value or isValid() to check if the context was successfully initialized.

A context can be made current against a given surface by calling makeCurrent(). When OpenGL rendering is done, call swapBuffers() to swap the front and back buffers of the surface, so that the newly rendered content becomes visible. To be able to support certain platforms, QOpenGLContext requires that you call makeCurrent() again before starting rendering a new frame, after calling swapBuffers().

If the context is temporarily not needed, such as when the application is not rendering, it can be useful to delete it in order to free resources. You can connect to the aboutToBeDestroyed() signal to clean up any resources that have been allocated with different ownership from the QOpenGLContext itself.

Once a QOpenGLContext is marked current your program can render to the context using the OpenGL wrappers like QOpenGLFunctions, QOpenGLBuffer, QOpenGLShaderProgram, and QOpenGLFramebufferObject. Alternatively, use the your platform OpenGL API directly although potentially at the cost of portability. The latter is necessary when wanting to use OpenGL 1.x or OpenGL ES 1.x.

Note

Additional documentation pending.