带有QT错误的OpenGL: ASSERT:“QOpenGLFunctions:::isInitialized(d_ptr)”。无法创建OpenGL上下文

I have recently made my first OpenGL program rendering a cube, which I extended to include some other basic features (rotate, zoom, pan, mouse selection of vertices). However, I think the program was using some version of OpenGL ES x.x because I could not use glReadPixels with gl_depth_component to enable mouse selection of only visible vertices.I have recently made my first OpenGL program re