Pegui

(Raspberry) Pi Easy GUI

⚡️ An async-first, IMGUI-inspired GUI engine for embedded Linux. ⚡️

🛠 Currently it's in developing 🛠

Why?

• ✨ Built on tokio, so it eats small amount of memory, runs blazing fast and just cool
• 🌧 Very simple app compiled with musl mode and compiled using cross build --release --target aarch64-unknown-linux-musl and optimizations in cargo.toml only takes 598.1 kilobytes (1.22 megabytes without them)!
• 🔄 Very easy to use
• 📋 This list will be bigger in the future

Repository Health Badges

Generated by GitHub Repository Analyzer

Quick start!

use embedded_graphics::{mono_font::{MonoTextStyle, ascii::FONT_6X10}, pixelcolor::BinaryColor}; // A library which pegui uses
use linux_embedded_hal::I2cdev; // For I2C connection
use log::{error, info}; // For logging
use ssd1306::{I2CDisplayInterface, Ssd1306, prelude::*}; // The display driver
use rppal::gpio::Gpio; // For buttons
use pegui::{App, ButtonTag, Buttons, Colors, Engine, Font, Settings, Ssd1306Display, ui::Ui, errors::Error};

#[tokio::main] // The library is asynchronous
async fn main() {
    let i2c = I2cdev::new("/dev/i2c-1").expect("Failed to open I2C! Please enable I2C and connect the screen if you did not");
    let interface = I2CDisplayInterface::new(i2c); // Creating the I2C connection
    let mut display = Ssd1306::new(
        interface,
        DisplaySize128x64,
        DisplayRotation::Rotate0
    ).into_buffered_graphics_mode(); // You should use into_buffered_graphics_mode()!
    if let Err(e) = display.init() {
        error!("Failed to init the screen! Everything on the screen could be placed with some mistakes or even dont appear. Error: {:?}", e);
    }; // Without init everything on the screen may move to some direction
    let app_state = AppState { counter: 0 };
    let gpio = Gpio::new().expect("Failed to init GPIO");
    let buttons: Vec<ButtonTag> = [(17, "fourth button"), (22, "third button"), (23, "second button"), (27, "first button")]
        .iter()
        .map(|pin| ButtonTag { pin: gpio.get(pin.0).expect(&format!("Failed to get GPIO pin {} with tag {}", pin.0, pin.1)).into_input_pullup(), tag: pin.1 })
        .collect::<Vec<ButtonTag>>(); // Initializing buttons
    Engine::new(
        Settings { 
            colors: Colors { main: BinaryColor::On, secondary: BinaryColor::Off }, 
            display: Ssd1306Display { display },
            framerate: 20,
            fonts: vec![ Font::new("default", MonoTextStyle::new(&FONT_6X10, BinaryColor::On)) ]
        },
        buttons,
        app_state
    ).await.start_rendering(true).await; // Initializing the engine and starting the render, true is for clearing the screen before every update call
}

struct AppState {
    counter: u32
} // Our app state

impl App for AppState {
    async fn update(&mut self, ui: &mut Ui, buttons: &Buttons) -> Error { // Library calls this function every 1000 / fps milliseconds
        info!("Buttons state: {:?}", buttons);
        ui.label(format!("Clicks: {}", self.counter), "default").await.ok(); // Creating a label with text
        if buttons.clicked("fourth button") { // Checking if the 4th button was clicked
            self.counter += 1;
        };
        Ok(())
    }
}

How to get max possible fps

To get max possible fps you can use this formula: BusSpeed(KHz) ÷ (ScreenWidth × ScreenHeight × 2) where 2 are some header bytes and some delays

Formula example

400.000 ÷ (128 × 64 × 2) = 400.000 ÷ 16384 ~= 24,41 fps ~= 24 fps

If you see these warnings (you have to initialize the logger first): Update took too much! (some number ms), you should a little decrease fps until warnings gone or just use this formula: 1000 ÷ number from warning - 4 where 4 is safety stock

Todo

• 🧊 Add different objects support
• 🕹️ Add buttons with easy navigation using buttons
• 🏷️ Update GPIO buttons tags for integrations with display buttons
• 💃 Add flexbox-like and grid-like API
• ♟ Add bitmap "videos" and just images support
• 📱 Add touchscreen support
• 💾 Add more drivers
• 🦀 Switch to no_std for microcontrollers support and leaner work
• 🌐 Add headless mode (via web interface)
• 📸 Add screen recording
• ❌ Become a millionaire
• 📋 This list will also be bigger in the future

Contributing

Please read CONTRIBUTING.md for details on our code of conduct and the process for submitting pull requests.

Code of Conduct

This project adheres to a Code of Conduct. By participating, you are expected to uphold this code.

Security

For security concerns, please refer to our Security Policy.