There is also a tool that can preview the GUI on the Linux, check the repo here.

• Operating System : Ubuntu 16.04
• arm-none-eabi-gcc : v4.9.3 (20150529)
• gcc : v 5.4.0 (20160609)
• make : GNU Make 4.1

$ git clone https://github.com/Joouis/EVGUI.git # proj $ git clone https://github.com/Joouis/EVGUI_Viewer.git # viewer

$ sudo apt-get install gcc-arm-none-eabi # ARM embedded gcc compiler

$ sudo apt-get install libx11-dev # x window library $ sudo apt-get install openocd # flash tool * tools [optional] + screen, tmux : serial communication + gdb, cgdb : gcc debugger (via make debug)

• proj

  $ cd parser/ $ make $ make flash

• viewer

  $ cd viewer/ $ make $ ./xdemo # show demo svg on linux

----------------------			-------------------			----------------			-----------
| presentation layer |	=>		| rendering layer |	=>		| output layer |	=>		| drivers |
----------------------			-------------------			----------------			-----------
* presentation layer: libsvgtiny, ezxml
* render layer		: twin
* output layer		: uGUI

* main()
	+ twin_fbdev_create()		: initialize hardware
	+ twin_svg_index_start()	: svg parsing and drawing
		-	svgtiny_parse()		: parse svg to drawing information
		-	render_path/text()	: call vector graphics library to finish drawing
	+ twin_fbdev_activate()		: first paint/update screen of hardware
	+ twin_dispatch()			: global loop for updating (window, screen, process input)

* manually copy svg (markup code) codes into apps/twin_svg.c via 'vim'
* flash binary files into MCU (Micro Control Unit)
* parsing svg codes into drawing information for vector graphics library

• proj/
  • apps/ - user code to build GUI
    • backend/ - drivers for hardware (stm32f429)
    • cmsis/ - general protocol to use the core of MCU
    • cmsis_boot/ - boot config
    • gdb.script - debug config
    • ImgToString.sh - convert svg codes to string
    • ld/ - linking scripts (ref)
    • libsvgtiny/ - svg and xml parser (analyze svg files for vector engine)
    • STM32F4xx_StdPeriph_Driver/ - STM32F4xx Standard peripheral drivers
    • syscalls/ - a malloc function for using external sdram
    • twin/ - vector graphics library
    • uGUI/ - mini GUI library as driver interface (ref: http://www.embeddedlightning.com/ugui/)
• viewer/
  • apps/ - user code to build GUI
    • backend/ - drivers for hardware (x11)
    • ImgToString.sh - convert svg codes to string
    • libsvgtiny/ - svg and xml parser (analyze svg files for vector engine)
    • src/ - vector graphics library (twin)
    • include/ - some extra twin libraries