Crate floem_cosmic_text
source ·Expand description
§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
[Buffer
], 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 floem_cosmic_text::{Attrs, Color, FontSystem, SwashCache, Buffer, Metrics};
// A FontSystem provides access to detected system fonts, create one per application
let mut font_system = FontSystem::new();
// A SwashCache stores rasterized glyphs, create one per application
let mut swash_cache = SwashCache::new();
// Text metrics indicate the font size and line height of a buffer
let metrics = Metrics::new(14.0, 20.0);
// A Buffer provides shaping and layout for a UTF-8 string, create one per text widget
let mut buffer = Buffer::new(&mut font_system, metrics);
// Borrow buffer together with the font system for more convenient method calls
let mut buffer = buffer.borrow_with(&mut font_system);
// Set a size for the text buffer, in pixels
buffer.set_size(80.0, 25.0);
// Attributes indicate what font to choose
let attrs = Attrs::new();
// Add some text!
buffer.set_text("Hello, Rust! 🦀\n", attrs);
// Perform shaping as desired
buffer.shape_until_scroll();
// Inspect the output runs
for run in 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 performance, instead use SwashCache directly)
buffer.draw(&mut swash_cache, text_color, |x, y, w, h, color| {
// Fill in your code here for drawing rectangles
});
Re-exports§
pub use unicode_segmentation;
pub use fontdb;
Structs§
- Text attributes
- List of text attributes to apply to a line
- An owned version of
Attrs
- Key for building a glyph cache
- Current cursor location
- A wrapper of [
Buffer
] for easy editing - A font
- Font attributes
- Global font metrics.
- Access system fonts
- The position of a cursor within a [
Buffer
]. - A laid out glyph
- A line of laid out glyphs
- A line of visible text for rendering
- An iterator of visible text lines, see
LayoutRun
- Metrics of text
- Describes the offset and dimensions of a rendered mask.
- A shaped glyph
- A shaped line (or paragraph)
- A shaped span (for bidirectional processing)
- A shaped word (for word wrapping)
- Cache for rasterizing with the swash scaler
- Scaled glyph image.
- A buffer of text that is shaped and laid out
- A line (or paragraph) of text that is shaped and laid out
- Specifies the weight of glyphs in the font, their degree of blackness or stroke thickness.
Enums§
- An action to perform on an
Editor
- Whether to associate cursors placed at a boundary between runs with the run before or after it.
- Align or justify
- Path command.
- A font family.
- An owned version of
Family
- A face width.
- Allows italic or oblique faces to be selected.
- Binning of subpixel position for cache optimization
- Content of a scaled glyph image.
- Wrapping mode
Statics§
Traits§
- A trait to allow easy replacements of
Editor
, likeSyntaxEditor