We can now complement our framebuffer image with Qt5 applications. Prior to the Qt5 release, Qt had its own window system implementation (QWS). Qt5 uses Qt platform plugins instead:
- For single-process applications with one main window, Qt5 recommends the EGLFS plugin, which uses the underlying graphical hardware acceleration, but can use others such as LinuxFB or DirectFB
- For multiple graphical processes the Wayland plugin must be used
EGL is an interface between OpenGL ES and the native windowing system (like X11 or Wayland) and EGLFS is the platform plugin that runs Qt5 applications over EGL and OpenGL ES 2.0 without a windowing system. EGLFS will force the first window to become full screen and become the root widget ...