anchor.diff:      libvorbis
       libvpx
       libwebp
  -    mesa_noglu
       mfx-dispatcher
       nvidia-cuda-toolkit
       nvidia-drivers
       openal
  +    opengl-dummy
       openh264
       openjpeg
       opus
  
positive.code:     "--${boolEn (openal != null)}-openal"
      #"--${boolEn (opencl != null)}-opencl"
      /**/"--disable-opencl"
      # OpenGL requires libX11 for GLX
      "--${boolEn (mesa_noglu != null && xorg.libX11 != null)}-opengl"
      "--${boolEn (openssl != null)}-openssl"
      "--disable-schannel"  # windows
      "--${boolEn (SDL_2 != null)}-sdl"
  
negative.code: #, opencl
  #, opencore-amr
  , opencv
  , opengl-dummy
  , openh264
  , openjpeg
  , openssl
  