egui/examples/custom_font/src/main.rs

#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
#![allow(rustdoc::missing_crate_level_docs)] // it's an example

use eframe::egui;

fn main() -> eframe::Result {
    env_logger::init(); // Log to stderr (if you run with `RUST_LOG=debug`).
    let options = eframe::NativeOptions {
        viewport: egui::ViewportBuilder::default().with_inner_size([320.0, 240.0]),
        ..Default::default()
    };
    eframe::run_native(
        "egui example: custom font",
        options,
        Box::new(|cc| Ok(Box::new(MyApp::new(cc)))),
    )
}

fn setup_custom_fonts(ctx: &egui::Context) {
    // Start with the default fonts (we will be adding to them rather than replacing them).
    let mut fonts = egui::FontDefinitions::default();

    // Install my own font (maybe supporting non-latin characters).
    // .ttf and .otf files supported.
    fonts.font_data.insert(
        "my_font".to_owned(),
        egui::FontData::from_static(include_bytes!(
            "../../../crates/epaint_default_fonts/fonts/Hack-Regular.ttf"
        )),
    );

    // Put my font first (highest priority) for proportional text:
    fonts
        .families
        .entry(egui::FontFamily::Proportional)
        .or_default()
        .insert(0, "my_font".to_owned());

    // Put my font as last fallback for monospace:
    fonts
        .families
        .entry(egui::FontFamily::Monospace)
        .or_default()
        .push("my_font".to_owned());

    // Tell egui to use these fonts:
    ctx.set_fonts(fonts);
}

struct MyApp {
    text: String,
}

impl MyApp {
    fn new(cc: &eframe::CreationContext<'_>) -> Self {
        setup_custom_fonts(&cc.egui_ctx);
        Self {
            text: "Edit this text field if you want".to_owned(),
        }
    }
}

impl eframe::App for MyApp {
    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
        egui::CentralPanel::default().show(ctx, |ui| {
            ui.heading("egui using custom fonts");
            ui.text_edit_multiline(&mut self.text);
        });
    }
}