LittlevGL - Open-source Embedded GUI Library in Rust

![Original LittlevGL demo image](lv_demo.png)

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.

LittlevGL is compatible with #![no_std] environments by default.

Official LittlevGL Website · C library repository · Live demo

--- ![Rust bindings usage demo code.](demo.png) ## Usage Edit your `Cargo.toml` file dependencies with: ``` $ cargo add lvgl ``` The build requires the environment variable bellow to be set: - `DEP_LV_CONFIG_PATH`: Path to the directory containing the `lv_conf.h` header file used for configuration of LittlevGL library. We recommend the `lv_conf.h` file to be in your project's root directory. If so, the command to build your project would be: ```shell script $ DEP_LV_CONFIG_PATH=`pwd` cargo build ``` ### Building for embedded environments We make use of `bindgen` for generating the bindings to LittlevGL at build time. There is a problem in cargo when building for `no_std`, so we need to use a workaround to build "lvgl-rs". The mainstrem issue in cargo is being tracked at [rust-lang/cargo#7915](https://github.com/rust-lang/cargo/issues/7915). ```shell $ DEP_LV_CONFIG_PATH=`pwd` cargo build -Zfeatures=build_dep ``` #### Requirements / Limitations LittlevGL C libary do allocate memory dynamically and we need to allocate memory on the heap in the Rust side as well ([`Box`](https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html)). That is required, so we can safely provide Rust pointers through FFI. For that reason, we do require [`alloc`](https://doc.rust-lang.org/alloc/) module to be available. ## Running the demo [This project contains examples that can run in a desktop simulator.](./examples) To run the `demo` example: ```shell $ DEP_LV_CONFIG_PATH=`pwd`/examples/include cargo run --example demo ```