LittlevGL2RTT/lvgl

Littlev Graphics Library

LittlevGL provides everything you need to create a Graphical User Interface (GUI) on embedded systems with easy-to-use graphical elements, beautiful visual effects and low memory footprint.
https://littlevgl.com

Check out the References where LittlevGL was used. You can add your project too!

Key features

• Powerful building blocks buttons, charts, lists, sliders, images, etc.
• Advanced graphics with animations, anti-aliasing, opacity, smooth scrolling
• Various input devices touch pad, mouse, keyboard, encoder, buttons, etc.
• Multi-language support with UTF-8 encoding
• Fully customizable graphical elements
• Hardware independent to use with any microcontroller or display
• Scalable to operate with little memory (50 kB Flash, 10 kB RAM)
• OS, External memory and GPU supported but not required
• Single frame buffer operation even with advances graphical effects
• Written in C for maximal compatibility
• Simulator to develop on PC without embedded hardware
• Tutorials, examples, themes for rapid development
• Documentation and API references online

Porting

In the simplest case you need 5 things:

1. Call lv_tick_inc(x) every x milliseconds in a Timer or Task (x should be between 1 and 10)
2. Register a function which can copy a pixel array to an area of the screen.
3. Register a function which can read an input device. (E.g. touch pad)
4. Copy lv_conf_templ.h as lv_conf.h and set at least LV_HOR_RES, LV_VER_RES and LV_COLOR_DEPTH.
5. Call lv_task_handler() periodically every few milliseconds. For a detailed description visit https://github.com/littlevgl/lvgl/wiki/Porting Or check the Porting tutorial

Project set-up

1. Clone or Download the lvgl repository: git clone https://github.com/littlevgl/lvgl.git
2. Create project with your preferred IDE and add the lvgl folder
3. Copy lvgl/lv_conf_templ.h as lv_conf.h next to the lvgl folder
4. In the lv_conf.h delete the first #if 0 and its #endif. Leave the default configuration for the first try.
5. In your main.c: #include "lvgl/lvgl.h"
   
6. In your main function:
   • lvgl_init();
   • tick, display and input device initialization (see above)
7. To test create a label: lv_obj_t * label = lv_label_create(lv_scr_act(), NULL);
   
8. In the main while(1) call lv_task_handler(); and make a few milliseconds delay (e.g. my_delay_ms(5);)
9. Compile the code and load it to your embedded hardware

PC Simulator

You can test the graphics library in a PC simulator, if you don't have an embedded hardware. The simulator uses SDL2 library to emulate a display on your monitor and a touch pad with your mouse.

There is a pre-configured PC project for Eclipse CDT in this repository: https://github.com/littlevgl/pc_simulator

Related repositories

• PC simulator: https://github.com/littlevgl/pc_simulator
• Projects: https://github.com/littlevgl/lv_projects
• Examples: https://github.com/littlevgl/lv_examples
• Drivers: https://github.com/littlevgl/lv_drivers

Screenshots

Contributing

See CONTRIBUTING.md

Donate

If you are pleased with this graphics library, found it useful, or are happy with the support you got, please help its further development: