Based on https://wiki.qt.io/RaspberryPi2EGLFS, https://thebugfreeblog.blogspot.com and https://github.com/raspberrypi/tools

• Uses the arm-rpi-4.9.3-linux-gnueabihf toolchain
• Tested only on RPi 3 (but should support pi1/pi2 just fine)
• Tested on clean Ubuntu 16.04 (64 bit) as host and clean Raspbian Jessie Lite 2017-01-11 on device
• Make sure to use 64 bit host OS as that's what the used toolchain is built for
• To use the toolchain once downloaded you must run source env.sh first to setup environment variables.

1. on host install tools and clone this repo

   # install tools
   sudo apt-get install build-essential sshpass git python pkg-config
   
   # clone this repo
   mkdir -p ~/raspi
   cd ~/raspi
   git clone https://github.com/Kukkimonsuta/rpi-buildqt.git .
   
   # add executable permissions (this may not be required)
   chmod +x scripts/0_init.sh
   ./scripts/0_init.sh

2. update values in env.sh (RPIDEV_DEVICE_* and optionally other settings)
3. prepare RPi (ideally use clean 'RASPBIAN JESSIE LITE' image)

   # change gpu memory to 256 MB
   sudo raspi-config
   
   # uncomment deb-src line
   sudo nano /etc/apt/sources.list
   
   # install qt dependencies
   sudo apt-get update
   sudo apt-get build-dep qt4-x11
   sudo apt-get build-dep libqt5gui5
   sudo apt-get install libudev-dev libinput-dev libts-dev libxcb-xinerama0-dev libxcb-xinerama0 libsmbclient-dev libssh-dev libv4l-dev libboost1.55-all-dev libbz2-dev
   
   # remove gstreamer
   sudo apt-get purge *gstreamer*
   
   # fix old egl
   sudo rm /usr/lib/arm-linux-gnueabihf/libEGL.so.1.0.0 /usr/lib/arm-linux-gnueabihf/libGLESv2.so.2.0.0
   sudo ln -s /opt/vc/lib/libEGL.so /usr/lib/arm-linux-gnueabihf/libEGL.so.1.0.0
   sudo ln -s /opt/vc/lib/libGLESv2.so /usr/lib/arm-linux-gnueabihf/libGLESv2.so.2.0.0
   
   # create qt install dir (must be at the path `QT_DEVICE_DIR`, owned by user `RPIDEV_DEVICE_USER` defined in `env.sh`)
   sudo mkdir -p /usr/local/qt5.8
   sudo chown pi:pi /usr/local/qt5.8
   
   # register the lib directory in ld
   echo /usr/local/qt5.8/lib | sudo tee /etc/ld.so.conf.d/qt5.8.conf

4. run 1_download.sh, this will download all required repositories
5. run 2_sync.sh, this will connect to RPi and creates a sysroot for crosscompilation
6. run 3.0_build_qtbase.sh, this will build and install qtbase
7. run 3.*_build_*.sh, this will build and install modules for qt. Feel free to add more from https://github.com/qt
8. run 4_build_piomxtextures.sh, this will build and install piomxtextures
9. run 5_sync_to_device.sh, this will copy qt5 to the device
10. on RPi run ldconfig

    sudo ldconfig
    

11. ~/piomxtextures_pocplayer /opt/vc/src/hello_pi/hello_video/test.h264