Fonterator

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Load fonts as vector graphics in pure Rust with advanced text layout. When you want to render text, fonterator gives you an iterator over footile PathOps, which you can easily pass right into footile.

Simple Example

use fonterator as font; // For parsing font file.
use footile::{FillRule, Plotter, Raster, Rgba8}; // For rendering font text.
use png_pong::{RasterBuilder, EncoderBuilder}; // For saving PNG

const FONT_SIZE: f32 = 32.0;

fn main() {
    // Example Text
    let english = "Raster Text With Font";
    let korean = "글꼴로 래스터 텍스트 사용";
    let japanese = "フォント付きラスタテキスト";

    // Init font, and paths.
    let font = font::monospace_font();

    // Init rendering.
    let mut p = Plotter::new(512, 512);
    let mut r = Raster::new(p.width(), p.height());

    // Render English Left Aligned.
    let path = font.render(
        english,
        (64.0, 0.0, 512.0 - 64.0, 512.0 - FONT_SIZE),
        (FONT_SIZE, FONT_SIZE),
        font::TextAlign::Left
    );
    let path: Vec<font::PathOp> = path.collect();
    r.over(p.fill(&path, FillRule::NonZero), Rgba8::rgb(0, 0, 0));

    // Render Korean Vertically
    let path = font.render(
        korean,
        (0.0, 0.0, 512.0, 512.0 - 32.0 * 7.0),
        (FONT_SIZE, FONT_SIZE),
        font::TextAlign::Vertical
    );
    let path: Vec<font::PathOp> = path.collect();
    r.over(p.fill(&path, FillRule::NonZero), Rgba8::rgb(0, 0, 0));

    // Render Japanese Vertically
    let path = font.render(
        japanese,
        (32.0, 0.0, 512.0, 512.0 - 32.0 * 7.0),
        (FONT_SIZE, FONT_SIZE),
        font::TextAlign::Vertical
    );
    let path: Vec<font::PathOp> = path.collect();
    r.over(p.fill(&path, FillRule::NonZero), Rgba8::rgb(0, 0, 0));

    // Save PNG
    let raster = RasterBuilder::new()
        .with_u8_buffer(512, 512, r.as_u8_slice());
    let mut out_data = Vec::new();
    let mut encoder = EncoderBuilder::new();
    let mut encoder = encoder.encode_rasters(&mut out_data);
    encoder.add_frame(&raster, 0).expect("Failed to add frame");
    std::fs::write("out.png", out_data).expect("Failed to save image");
}

Features

• Load TTF/OTF fonts and font collections.
• Automatic kerning and font layout.
• Horizontal and vertical text layout.
• Left-to-right and right-to-left text layout.
• Use fallback fonts if a character is not available from one font.
• Align text left/center/right/vertical
• Line Wrapping

TODO

• Arabic and other script text shaping
• Better interoperability for monospace when mixing scripts.

Contributing

Contributors are always welcome! Whether it is a bug report, bug fix, feature request, feature implementation or whatever. Don’t be shy about getting involved. I always make time to fix bugs, so usually a patched version of the library will be out soon after a report. Features take me longer, though. I’ll also always listen to any design critiques you have. If you have any questions you can email me at jeronlau@plopgrizzly.com. Otherwise, here’s a link to the issues on GitHub.

And, as always, make sure to always follow the code of conduct. Happy coding!

License

This repository is licensed under either of the following:

• MIT License (MIT) - See accompanying file LICENSE_MIT.txt or copy at https://opensource.org/licenses/MIT
• Boost Software License (BSL-1.0) - See accompanying file LICENSE_BSL.txt or copy at https://www.boost.org/LICENSE_1_0.txt

at your option.

Contribution Licensing

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you shall be dual licensed as above without any additional terms or conditions.