embedded-text

TextBox for embedded-graphics.

This crate provides a configurable TextBox to render multiline text inside a bounding Rectangle using embedded-graphics.

TextBox supports the common text alignments:

• Horizontal:
  • Left
  • Right
  • Center
  • Justified
• Vertical:
  • Top
  • Middle
  • Bottom

TextBox also supports some special characters not handled by embedded-graphics' Text:

• non-breaking space (\u{200b})
• zero-width space (\u{a0})
• soft hyphen (\u{ad})
• carriage return (\r)
• tab (\t) with configurable tab size

TextBox also supports text coloring using ANSI escape codes via the Ansi plugin.

Example

The examples are based on the embedded-graphics simulator. The simulator is built on top of SDL2. See the simulator README for more information.

use embedded_graphics::{
    mono_font::{ascii::FONT_6X10, MonoTextStyle},
    pixelcolor::BinaryColor,
    prelude::*,
    primitives::Rectangle,
};
use embedded_graphics_simulator::{
    BinaryColorTheme, OutputSettingsBuilder, SimulatorDisplay, Window,
};
use embedded_text::{
    alignment::HorizontalAlignment,
    style::{HeightMode, TextBoxStyleBuilder},
    TextBox,
};

fn main() {
    let text = "Hello, World!\n\
    A paragraph is a number of lines that end with a manual newline. Paragraph spacing is the \
    number of pixels between two paragraphs.\n\
    Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when \
    an unknown printer took a galley of type and scrambled it to make a type specimen book.";

    // Specify the styling options:
    // * Use the 6x10 MonoFont from embedded-graphics.
    // * Draw the text fully justified.
    // * Use `FitToText` height mode to stretch the text box to the exact height of the text.
    // * Draw the text with `BinaryColor::On`, which will be displayed as light blue.
    let character_style = MonoTextStyle::new(&FONT_6X10, BinaryColor::On);
    let textbox_style = TextBoxStyleBuilder::new()
        .height_mode(HeightMode::FitToText)
        .alignment(HorizontalAlignment::Justified)
        .paragraph_spacing(6)
        .build();

    // Specify the bounding box. Note the 0px height. The `FitToText` height mode will
    // measure and adjust the height of the text box in `into_styled()`.
    let bounds = Rectangle::new(Point::zero(), Size::new(128, 0));

    // Create the text box and apply styling options.
    let text_box = TextBox::with_textbox_style(text, bounds, character_style, textbox_style);

    // Create a simulated display with the dimensions of the text box.
    let mut display = SimulatorDisplay::new(text_box.bounding_box().size);

    // Draw the text box.
    text_box.draw(&mut display).unwrap();

    // Set up the window and show the display's contents.
    let output_settings = OutputSettingsBuilder::new()
        .theme(BinaryColorTheme::OledBlue)
        .scale(2)
        .build();
    Window::new("TextBox example with paragraph spacing", &output_settings).show_static(&display);
}

Cargo features

• plugin (experimental): allows implementing custom plugins.
• ansi: enables ANSI sequence support using the Ansi plugin.

Development setup

Minimum supported Rust version

The minimum supported Rust version for embedded-text is 1.61.0 or greater. Ensure you have the latest stable version of Rust installed, preferably through https://rustup.rs.

Installation

For setup in general, follow the installation instructions for embedded-graphics.

To install SDL2 on Windows, see https://github.com/Rust-SDL2/rust-sdl2#windows-msvc

Attribution

The last paragraph of the example text is copied from https://www.lipsum.com