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diff --git a/src/libs/lvgl/README.md b/src/libs/lvgl/README.md index 9d170887..7324fa9f 100644 --- a/src/libs/lvgl/README.md +++ b/src/libs/lvgl/README.md @@ -1,238 +1,128 @@ -<h1 align="center"> LittlevGL - Open-source Embedded GUI Library</h1> -<p align="center"> -<a href="https://github.com/littlevgl/lvgl/blob/master/LICENCE.txt"><img src="https://img.shields.io/badge/licence-MIT-blue.svg"></a> -<a href="https://github.com/littlevgl/lvgl/releases/tag/v6.0"><img src="https://img.shields.io/badge/version-6.0-blue.svg"></a> -</p> +<h1 align="center"> LVGL - Light and Versatile Graphics Library</h1> <p align="center"> -<img src="https://littlevgl.com/github/cover_ori_reduced_2.gif"> +<img src="https://lvgl.io/assets/images/img_1.png"> </p> <p align="center"> -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. +LVGL provides everything you need to create embedded GUI with easy-to-use graphical elements, beautiful visual effects and low memory footprint. </p> <h4 align="center"> -<a href="https://littlevgl.com">Website </a> · -<a href="https://littlevgl.com/live-demo">Live demo</a> · -<a href="https://docs.littlevgl.com/en/html/get-started/pc-simulator.html">Simulator</a> · -<a href="https://forum.littlevgl.com">Forum</a> · -<a href="https://docs.littlevgl.com/">Docs</a> · -<a href="https://blog.littlevgl.com/">Blog</a> +<a href="https://lvgl.io">Website </a> · +<a href="https://lvgl.io/demos">Online demo</a> · +<a href="https://lvgl.github.io/lv_examples/">Nightly demos</a> · +<a href="https://docs.lvgl.io/">Docs</a> · +<a href="https://forum.lvgl.io">Forum</a> </h4> --- -- [Features](#features) -- [Supported devices](#supported-devices) -- [Quick start in a simulator](#quick-start-in-a-simulator) -- [Add LittlevGL to your project](#add-littlevgl-to-your-project) -- [Learn the basics](#learn-the-basics) -- [Examples](#examples) -- [Contributing](#contributing) -- [Donate](#donate) - - ## Features -* **Powerful building blocks** buttons, charts, lists, sliders, images, etc. -* **Advanced graphics** with animations, anti-aliasing, opacity, smooth scrolling -* **Simultaneously use various input devices** touchscreen, mouse, keyboard, encoder, buttons, etc. -* **Simultaneously use multiple displays** i.e. monochrome and color display -* **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 (64 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 -* **Micropython Binding** exposes [LittlevGL API in Micropython](https://blog.littlevgl.com/2019-02-20/micropython-bindings) -* **Simulator** to develop on PC without embedded hardware -* **Tutorials, examples, themes** for rapid development -* **Documentation** and API references - -## Supported devices -Basically, every modern controller - which is able to drive a display - is suitable to run LittlevGL. The minimal requirements: -- 16, 32 or 64 bit microcontroller or processor -- > 16 MHz clock speed is recommended -- Flash/ROM: > 64 kB for the very essential components (> 180 kB is recommended) -- RAM: - - Static RAM usage: ~8..16 kB depending on the used features and objects types - - Stack: > 2kB (> 4 kB is recommended) - - Dynamic data (heap): > 4 KB (> 16 kB is recommended if using several objects). - Set by `LV_MEM_SIZE` in *lv_conf.h*. - - Display buffer: > *"Horizontal resolution"* pixels (> 10 × *"Horizontal resolution"* is recommended) -- C99 or newer compiler +* Powerful [building blocks](https://docs.lvgl.io/latest/en/html/widgets/index.html): buttons, charts, lists, sliders, images, etc. +* Advanced graphics: animations, anti-aliasing, opacity, smooth scrolling +* Use [various input devices](https://docs.lvgl.io/latest/en/html/overview/indev.html): touchscreen, mouse, keyboard, encoder, buttons, etc. +* Use [multiple displays](https://docs.lvgl.io/latest/en/html/overview/display.html): e.g. monochrome and color display +* Hardware independent to use with any microcontroller or display +* Scalable to operate with little memory (64 kB Flash, 10 kB RAM) +* Multi-language support with UTF-8 handling, Bidirectional and Arabic script support +* Fully customizable graphical elements via [CSS-like styles](https://docs.lvgl.io/latest/en/html/overview/style.html) +* OS, External memory and GPU are supported but not required +* Smooth rendering even with a [single frame buffer](https://docs.lvgl.io/latest/en/html/porting/display.html) +* Written in C for maximal compatibility (C++ compatible) +* Micropython Binding exposes [LVGL API in Micropython](https://blog.lvgl.io/2019-02-20/micropython-bindings) +* [Simulator](https://docs.lvgl.io/latest/en/html/get-started/pc-simulator.html) to develop on PC without embedded hardware +* [Examples](lv_examples) and tutorials for rapid development +* [Documentation](http://docs.lvgl.io/) and API references + +## Requirements +Basically, every modern controller (which is able to drive a display) is suitable to run LVGL. The minimal requirements are: + +<table> + <tr> + <td> <strong>Name</strong> </td> + <td><strong>Minimal</strong></td> + <td><strong>Recommended</strong></td> + </tr> + <tr> + <td><strong>Architecture</strong></td> + <td colspan="2">16, 32 or 64 bit microcontroller or processor</td> + </tr> + <tr> + <td> <strong>Clock</strong></td> + <td> > 16 MHz </td> + <td> > 48 MHz</td> + </tr> + + <tr> + <td> <strong>Flash/ROM</strong></td> + <td> > 64 kB </td> + <td> > 180 kB</td> + </tr> + + <tr> + <td> <strong>Static RAM</strong></td> + <td> > 2 kB </td> + <td> > 4 kB</td> + </tr> + + <tr> + <td> <strong>Stack</strong></td> + <td> > 2 kB </td> + <td> > 8 kB</td> + </tr> + + <tr> + <td> <strong>Heap</strong></td> + <td> > 2 kB </td> + <td> > 8 kB</td> + </tr> + + <tr> + <td> <strong>Display buffer</strong></td> + <td> > 1 × <em>hor. res.</em> pixels </td> + <td> > 10 × <em>hor. res.</em> pixels </td> + </tr> + + <tr> + <td> <strong>Compiler</strong></td> + <td colspan="2"> C99 or newer </td> + </tr> +</table> *Note that the memory usage might vary depending on the architecture, compiler and build options.* -Just to mention some **platforms**: -- STM32F1, STM32F3, [STM32F4](https://blog.littlevgl.com/2017-07-15/stm32f429_disco_port), [STM32F7](https://github.com/littlevgl/stm32f746_disco_no_os_sw4stm32) +Just to mention some platforms: +- STM32F1, STM32F3, STM32F4, STM32F7, STM32L4, STM32L5, STM32H7 - Microchip dsPIC33, PIC24, PIC32MX, PIC32MZ -- NXP Kinetis, LPC, iMX -- [Linux frame buffer](https://blog.littlevgl.com/2018-01-03/linux_fb) (/dev/fb) -- [Raspberry PI](http://www.vk3erw.com/index.php/16-software/63-raspberry-pi-official-7-touchscreen-and-littlevgl) -- [Espressif ESP32](https://github.com/littlevgl/esp32_ili9431) -- Nordic nrf52 -- Quectell M66 - -## Quick start in a simulator -The easiest way to get started with LittlevGL is to run it in a simulator on your PC without any embedded hardware. - -Choose a project with your favourite IDE: - -| Eclipse | CodeBlocks | Visual Studio | PlatformIO | Qt Creator | -|-------------|-------------|---------------|-----------|------------| -| [](https://github.com/littlevgl/pc_simulator_sdl_eclipse) | [](https://github.com/littlevgl/pc_simulator_win_codeblocks) | [](https://github.com/littlevgl/visual_studio_2017_sdl_x64) | [](https://github.com/littlevgl/pc_simulator_sdl_platformio) | [](https://blog.littlevgl.com/2019-01-03/qt-creator) | -| Cross-platform<br>with SDL<br>(Recommended on<br>Linux and Mac) | Native Windows | Windows<br>with SDL | Cross-platform<br>with SDL | Cross-platform<br>with SDL | - - -## Add LittlevGL to your project - -The steps below show how to setup LittlevGL on an embedded system with a display and a touchpad. -You can use the [Simulators](https://docs.littlevgl.com/en/html/get-started/pc-simulator) to get ready to use projects which can be run on your PC. - -1. [Download](https://littlevgl.com/download) or [Clone](https://github.com/littlevgl/lvgl) the library -2. Copy the `lvgl` folder into your project -3. Copy `lvgl/lv_conf_template.h` as `lv_conf.h` next to the `lvgl` folder and set at least `LV_HOR_RES_MAX`, `LV_VER_RES_MAX` and `LV_COLOR_DEPTH`. -4. Include `lvgl/lvgl.h` where you need to use LittlevGL related functions. -5. Call `lv_tick_inc(x)` every `x` milliseconds **in a Timer or Task** (`x` should be between 1 and 10). It is required for the internal timing of LittlevGL. -6. Call `lv_init()` -7. Create a display buffer for LittlevGL -```c -static lv_disp_buf_t disp_buf; -static lv_color_t buf[LV_HOR_RES_MAX * 10]; /*Declare a buffer for 10 lines*/ -lv_disp_buf_init(&disp_buf, buf, NULL, LV_HOR_RES_MAX * 10); /*Initialize the display buffer*/ -``` -8. Implement and register a function which can **copy a pixel array** to an area of your display: -```c -lv_disp_drv_t disp_drv; /*Descriptor of a display driver*/ -lv_disp_drv_init(&disp_drv); /*Basic initialization*/ -disp_drv.flush_cb = my_disp_flush; /*Set your driver function*/ -disp_drv.buffer = &disp_buf; /*Assign the buffer to the display*/ -lv_disp_drv_register(&disp_drv); /*Finally register the driver*/ - -void my_disp_flush(lv_disp_t * disp, const lv_area_t * area, lv_color_t * color_p) -{ - int32_t x, y; - for(y = area->y1; y <= area->y2; y++) { - for(x = area->x1; x <= area->x2; x++) { - set_pixel(x, y, *color_p); /* Put a pixel to the display.*/ - color_p++; - } - } - - lv_disp_flush_ready(disp); /* Indicate you are ready with the flushing*/ -} - -``` -9. Implement and register a function which can **read an input device**. E.g. for a touch pad: -```c -lv_indev_drv_init(&indev_drv); /*Descriptor of a input device driver*/ -indev_drv.type = LV_INDEV_TYPE_POINTER; /*Touch pad is a pointer-like device*/ -indev_drv.read_cb = my_touchpad_read; /*Set your driver function*/ -lv_indev_drv_register(&indev_drv); /*Finally register the driver*/ - -bool my_touchpad_read(lv_indev_drv_t * indev_driver, lv_indev_data_t * data) -{ - static lv_coord_t last_x = 0; - static lv_coord_t last_y = 0; - - /*Save the state and save the pressed coordinate*/ - data->state = touchpad_is_pressed() ? LV_INDEV_STATE_PR : LV_INDEV_STATE_REL; - if(data->state == LV_INDEV_STATE_PR) touchpad_get_xy(&last_x, &last_y); - - /*Set the coordinates (if released use the last pressed coordinates)*/ - data->point.x = last_x; - data->point.y = last_y; - - return false; /*Return `false` because we are not buffering and no more data to read*/ -} -``` -10. Call `lv_task_handler()` periodically every few milliseconds in the main `while(1)` loop, in Timer interrupt or in an Operation system task. -It will redraw the screen if required, handle input devices etc. - - -## Learn the basics - -### Objects (Widgets) - -The graphical elements like Buttons, Labels, Sliders, Charts etc are called objects in LittelvGL. Go to [Object types](https://docs.littlevgl.com/en/html/object-types/index) to see the full list of available types. - -Every object has a parent object. The child object moves with the parent and if you delete the parent the children will be deleted too. Children can be visible only on their parent. - -The *screen* are the "root" parents. To get the current screen call `lv_scr_act()`. - -You can create a new object with `lv_<type>_create(parent, obj_to_copy)`. It will return an `lv_obj_t *` variable which should be used as a reference to the object to set its parameters. -The first parameter is the desired *parent*, te second parameters can be an object to copy (`NULL` is unused). -For example: -```c -lv_obj_t * slider1 = lv_slider_create(lv_scr_act(), NULL); -``` - -To set some basic attribute `lv_obj_set_<paramters_name>(obj, <value>)` function can be used. For example: -```c -lv_obj_set_x(btn1, 30); -lv_obj_set_y(btn1, 10); -lv_obj_set_size(btn1, 200, 50); -``` - -The objects has type specific parameters too which can be set by `lv_<type>_set_<paramters_name>(obj, <value>)` functions. For example: -```c -lv_slider_set_value(slider1, 70, LV_ANIM_ON); -``` - -To see the full API visit the documentation of the object types or the related header file (e.g. `lvgl/src/lv_objx/lv_slider.h`). - -### Styles -Styles can be assigned to the objects to changed their appearance. A style describes the appearance of rectangle-like objects (like a button or slider), texts, images and lines at once. - -You can create a new style like this: -```c -static lv_style_t style1; /*Declare a new style. Should be `static`*/ -lv_style_copy(&style1, &lv_style_plain); /*Copy a built-in style*/ -style1.body.main_color = LV_COLOR_RED; /*Main color*/ -style1.body.grad_color = lv_color_hex(0xffd83c) /*Gradient color (orange)*/ -style1.body.radius = 3; -style1.text.color = lv_color_hex3(0x0F0) /*Label color (green)*/ -style1.text.font = &lv_font_dejavu_22; /*Change font*/ -... -``` - -To set a new style for an object use the `lv_<type>set_style(obj, LV_<TYPE>_STYLE_<NAME>, &my_style)` functions. For example: -```c -lv_slider_set_style(slider1, LV_SLIDER_STYLE_BG, &slider_bg_style); -lv_slider_set_style(slider1, LV_SLIDER_STYLE_INDIC, &slider_indic_style); -lv_slider_set_style(slider1, LV_SLIDER_STYLE_KNOB, &slider_knob_style); -``` - -If an object's style is `NULL` then it will inherit its parent's style. For example, the labels' style are `NULL` by default. If you place them on a button then they will use the `style.text` properties from the button's style. - -Learn more in [Style overview](https://docs.littlevgl.com/en/html/overview/style) section. - -### Events -Events are used to inform the user if something has happened with an object. You can assign a callback to an object which will be called if the object is clicked, released, dragged, being deleted etc. It should look like this: - -```c -lv_obj_set_event_cb(btn, btn_event_cb); /*Assign a callback to the button*/ - -... - -void btn_event_cb(lv_obj_t * btn, lv_event_t event) -{ - if(event == LV_EVENT_CLICKED) { - printf("Clicked\n"); - } -} -``` - -Learn more about the events in the [Event overview](https://docs.littlevgl.com/en/html/overview/event) section. - - -## Examples +- NXP: Kinetis, LPC, iMX, iMX RT +- [Linux frame buffer](https://blog.lvgl.io/2018-01-03/linux_fb) (/dev/fb) +- [Raspberry Pi](http://www.vk3erw.com/index.php/16-software/63-raspberry-pi-official-7-touchscreen-and-littlevgl) +- [Espressif ESP32](https://github.com/lvgl/lv_port_esp32) +- [Infineon Aurix](https://github.com/lvgl/lv_port_aurix) +- Nordic NRF52 Bluetooth modules +- Quectel modems + +## Get started +This list shows the recommended way of learning the library: +1. Check the [Online demos](https://lvgl.io/demos) to see LVGL in action (3 minutes) +2. Read the [Introduction](https://docs.lvgl.io/latest/en/html/intro/index.html) page of the documentation (5 minutes) +3. Get familiar with the basics on the [Quick overview](https://docs.lvgl.io/latest/en/html/get-started/quick-overview.html) page (15 minutes) +4. Set up a [Simulator](https://docs.lvgl.io/latest/en/html/get-started/pc-simulator.html) (10 minutes) +5. Try out some [Examples](https://github.com/lvgl/lv_examples/) +6. Port LVGL to a board. See the [Porting](https://docs.lvgl.io/latest/en/html/porting/index.html) guide or check the ready to use [Projects](https://github.com/lvgl?q=lv_port_&type=&language=) +7. Read the [Overview](https://docs.lvgl.io/latest/en/html/overview/index.html) page to get a better understanding of the library (2-3 hours) +8. Check the documentation of the [Widgets](https://docs.lvgl.io/latest/en/html/widgets/index.html) to see their features and usage +9. If you have questions go to the [Forum](http://forum.lvgl.io/) +10. Read the [Contributing](https://docs.lvgl.io/latest/en/html/contributing/index.html) guide to see how you can help to improve LVGL (15 minutes) + +## Examples + +For more examples see the [lv_examples](https://github.com/lvgl/lv_examples) repository. ### Button with label ```c -lv_obj_t * btn = lv_btn_create(lv_scr_act(), NULL); /*Add a button the current screen*/ +lv_obj_t * btn = lv_btn_create(lv_scr_act(), NULL); /*Add a button to the current screen*/ lv_obj_set_pos(btn, 10, 10); /*Set its position*/ lv_obj_set_size(btn, 100, 50); /*Set its size*/ lv_obj_set_event_cb(btn, btn_event_cb); /*Assign a callback to the button*/ @@ -249,121 +139,10 @@ void btn_event_cb(lv_obj_t * btn, lv_event_t event) } } ``` - - -### Button with styles -Add styles to the previously button from the previous example -```c -static lv_style_t style_btn_rel; /*A variable to store the released style*/ -lv_style_copy(&style_btn_rel, &lv_style_plain); /*Initialize from a built-in style*/ -style_btn_rel.body.border.color = lv_color_hex3(0x269); -style_btn_rel.body.border.width = 1; -style_btn_rel.body.main_color = lv_color_hex3(0xADF); -style_btn_rel.body.grad_color = lv_color_hex3(0x46B); -style_btn_rel.body.shadow.width = 4; -style_btn_rel.body.shadow.type = LV_SHADOW_BOTTOM; -style_btn_rel.body.radius = LV_RADIUS_CIRCLE; -style_btn_rel.text.color = lv_color_hex3(0xDEF); - -static lv_style_t style_btn_pr; /*A variable to store the pressed style*/ -lv_style_copy(&style_btn_pr, &style_btn_rel); /*Initialize from the released style*/ -style_btn_pr.body.border.color = lv_color_hex3(0x46B); -style_btn_pr.body.main_color = lv_color_hex3(0x8BD); -style_btn_pr.body.grad_color = lv_color_hex3(0x24A); -style_btn_pr.body.shadow.width = 2; -style_btn_pr.text.color = lv_color_hex3(0xBCD); - -lv_btn_set_style(btn, LV_BTN_STYLE_REL, &style_btn_rel); /*Set the button's released style*/ -lv_btn_set_style(btn, LV_BTN_STYLE_PR, &style_btn_pr); /*Set the button's pressed style*/ -``` - - - -### Slider and object alignment -```c -lv_obj_t * label; - -... - -/* Create a slider in the center of the display */ -lv_obj_t * slider = lv_slider_create(lv_scr_act(), NULL); -lv_obj_set_width(slider, 200); /*Set the width*/ -lv_obj_align(slider, NULL, LV_ALIGN_CENTER, 0, 0); /*Align to the center of the parent (screen)*/ -lv_obj_set_event_cb(slider, slider_event_cb); /*Assign an event function*/ - -/* Create a label below the slider */ -label = lv_label_create(lv_scr_act(), NULL); -lv_label_set_text(label, "0"); -lv_obj_set_auto_realign(slider, true); -lv_obj_align(label, slider, LV_ALIGN_OUT_BOTTOM_MID, 0, 10); - -... + -void slider_event_cb(lv_obj_t * slider, lv_event_t event) -{ - if(event == LV_EVENT_VALUE_CHANGED) { - static char buf[4]; /* max 3 bytes for number plus 1 null terminating byte */ - snprintf(buf, 4, "%u", lv_slider_get_value(slider)); - lv_label_set_text(slider_label, buf); /*Refresh the text*/ - } -} -``` - - - -### List and themes -```c -/*Texts of the list elements*/ -const char * txts[] = {"First", "Second", "Third", "Forth", "Fifth", "Sixth", NULL}; - -/* Initialize and set a theme. `LV_THEME_NIGHT` needs to enabled in lv_conf.h. */ -lv_theme_t * th = lv_theme_night_init(20, NULL); -lv_theme_set_current(th); - -/*Create a list*/ -lv_obj_t* list = lv_list_create(lv_scr_act(), NULL); -lv_obj_set_size(list, 120, 180); -lv_obj_set_pos(list, 10, 10); - -/*Add buttons*/ -uint8_t i; -for(i = 0; txts[i]; i++) { - lv_obj_t * btn = lv_list_add_btn(list, LV_SYMBOL_FILE, txts[i]); - lv_obj_set_event_cb(btn, list_event); /*Assign event function*/ - lv_btn_set_toggle(btn, true); /*Enable on/off states*/ -} - -/* Initialize and set an other theme. `LV_THEME_MATERIAL` needs to enabled in lv_conf.h. - * If `LV_TEHE_LIVE_UPDATE 1` then the previous list's style will be updated too.*/ -th = lv_theme_material_init(210, NULL); -lv_theme_set_current(th); - -/*Create an other list*/ -list = lv_list_create(lv_scr_act(), NULL); -lv_obj_set_size(list, 120, 180); -lv_obj_set_pos(list, 150, 10); - -/*Add buttons with the same texts*/ -for(i = 0; txts[i]; i++) { - lv_obj_t * btn = lv_list_add_btn(list, LV_SYMBOL_FILE, txts[i]); - lv_obj_set_event_cb(btn, list_event); - lv_btn_set_toggle(btn, true); -} - -... - -static void list_event(lv_obj_t * btn, lv_event_t e) -{ - if(e == LV_EVENT_CLICKED) { - printf("%s\n", lv_list_get_btn_text(btn)); - } - -} -``` - - -### Use LittlevGL from Micropython -Learn more about [Micropython](https://docs.littlevgl.com/en/html/get-started/micropython). +### LVGL from Micropython +Learn more about [Micropython](https://docs.lvgl.io/latest/en/html/get-started/micropython.html). ```python # Create a Button and a Label scr = lv.obj() @@ -377,22 +156,6 @@ lv.scr_load(scr) ``` ## Contributing -To ask questions please use the [Forum](https://forum.littlevgl.com). -For development-related things (bug reports, feature suggestions) use [GitHub's Issue tracker](https://github.com/littlevgl/lvgl/issues). - -If you are interested in contributing to LittlevGL you can -- **Help others** in the [Forum](https://forum.littlevgl.com). -- **Inspire people** by speaking about your project in [My project](https://forum.littlevgl.com/c/my-projects) category in the Forum or add it to the [References](https://blog.littlevgl.com/2018-12-26/references) post -- **Improve and/or translate the documentation.** Go to the [Documentation](https://github.com/littlevgl/docs) repository to learn more -- **Write a blog post** about your experiences. See how to do it in the [Blog](https://github.com/littlevgl/blog) repository -- **Report and/or fix bugs** in [GitHub's issue tracker](https://github.com/littlevgl/lvgl/issues) -- **Help in the developement**. Check the [Open issues](https://github.com/littlevgl/lvgl/issues) especially the ones with [Help wanted](https://github.com/littlevgl/lvgl/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22) label and tell your ideas about a topic or implement a feature. - -It should be useful to read the -- [Contributing guide](https://blog.littlevgl.com/2018-12-06/contributing) -- [Coding style guide](https://github.com/littlevgl/lvgl/blob/master/docs/CODING_STYLE.md) - -## Donate -If you are pleased with the library, found it useful, or you are happy with the support you got, please help its further development: +LVGL is an open project and contribution is very welcome. There are many ways to contribute from simply speaking about your project, through writing examples, improving the documentation, fixing bugs to hosing your own project under in LVGL. -[](https://littlevgl.com/donate) +For a detailed description of contribution opportunities visit the [Contributing](https://docs.lvgl.io/latest/en/html/contributing/index.html) section of the documentation. |