cosmic-text/src/lib.rs

// SPDX-License-Identifier: MIT OR Apache-2.0

//! # COSMIC Text
//!
//! This library provides advanced text handling in a generic way. It provides abstractions for
//! shaping, font discovery, font fallback, layout, rasterization, and editing. Shaping utilizes
//! rustybuzz, font discovery utilizes fontdb, and the rasterization is optional and utilizes
//! swash. The other features are developed internal to this library.
//!
//! It is recommended that you start by creating a [FontSystem], after which you can create a
//! [TextBuffer], provide it with some text, and then inspect the layout it produces. At this
//! point, you can use the `SwashCache` to rasterize glyphs into either images or pixels.
//!
//! ```
//! use cosmic_text::{Attrs, Color, FontSystem, SwashCache, TextBuffer, TextMetrics};
//!
//! // A FontSystem provides access to detected system fonts, create one per application
//! let font_system = FontSystem::new();
//!
//! // A SwashCache stores rasterized glyphs, create one per application
//! let mut swash_cache = SwashCache::new(&font_system);
//!
//! // Text metrics indicate the font size and line height of a buffer
//! let metrics = TextMetrics::new(14, 20);
//!
//! // A TextBuffer provides shaping and layout for a UTF-8 string, create one per text widget
//! let mut text_buffer = TextBuffer::new(&font_system, metrics);
//!
//! // Set a size for the text buffer, in pixels
//! text_buffer.set_size(80, 25);
//!
//! // Attributes indicate what font to choose
//! let attrs = Attrs::new();
//!
//! // Add some text!
//! text_buffer.set_text("Hello, Rust! 🦀\n", attrs);
//!
//! // Perform shaping as desired
//! text_buffer.shape_until_scroll();
//!
//! // Inspect the output runs
//! for run in text_buffer.layout_runs() {
//!     for glyph in run.glyphs.iter() {
//!         println!("{:#?}", glyph);
//!     }
//! }
//!
//! // Create a default text color
//! let text_color = Color::rgb(0xFF, 0xFF, 0xFF);
//!
//! // Draw the buffer (for perfomance, instead use SwashCache directly)
//! text_buffer.draw(&mut swash_cache, text_color, |x, y, w, h, color| {
//!     // Fill in your code here for drawing rectangles
//! });
//! ```

pub use self::attrs::*;
mod attrs;

pub use self::buffer::*;
mod buffer;

pub use self::cache::*;
mod cache;

pub use self::font::*;
mod font;

pub use self::layout::*;
mod layout;

pub use self::shape::*;
mod shape;

#[cfg(feature = "swash")]
pub use self::swash::*;
#[cfg(feature = "swash")]
mod swash;