bevy/crates/bevy_text/src/lib.rs
Bruce Mitchener 0db999c795
Add some more docs for bevy_text. (#9873)
# Objective

- Have more docs for `bevy_text` to avoid reading the source code for
some things.

## Solution

- Add some additional docs.

## Changelog

- `TextSettings.max_font_atlases` in `bevy_text` has been renamed to `
TextSettings.soft_max_font_atlases`.

## Migration Guide

- Usages of `TextSettings.max_font_atlases` from `bevy_text` must be
changed to `TextSettings.soft_max_font_atlases`.
2023-10-27 18:53:57 +00:00

123 lines
4.1 KiB
Rust

#![allow(clippy::type_complexity)]
mod error;
mod font;
mod font_atlas;
mod font_atlas_set;
mod font_loader;
mod glyph_brush;
mod pipeline;
mod text;
mod text2d;
pub use error::*;
pub use font::*;
pub use font_atlas::*;
pub use font_atlas_set::*;
pub use font_loader::*;
pub use glyph_brush::*;
pub use pipeline::*;
pub use text::*;
pub use text2d::*;
pub mod prelude {
#[doc(hidden)]
pub use crate::{Font, Text, Text2dBundle, TextAlignment, TextError, TextSection, TextStyle};
}
use bevy_app::prelude::*;
use bevy_asset::AssetApp;
#[cfg(feature = "default_font")]
use bevy_asset::{load_internal_binary_asset, Handle};
use bevy_ecs::prelude::*;
use bevy_render::{camera::CameraUpdateSystem, ExtractSchedule, RenderApp};
use bevy_sprite::SpriteSystem;
use std::num::NonZeroUsize;
/// Adds text rendering support to an app.
///
/// When the `bevy_text` feature is enabled with the `bevy` crate, this
/// plugin is included by default in the `DefaultPlugins`.
#[derive(Default)]
pub struct TextPlugin;
/// Settings used to configure the [`TextPlugin`].
#[derive(Resource)]
pub struct TextSettings {
/// Soft maximum number of font atlases supported in a [`FontAtlasSet`]. When this is exceeded,
/// a warning will be emitted a single time. The [`FontAtlasWarning`] resource ensures that
/// this only happens once.
pub soft_max_font_atlases: NonZeroUsize,
/// Allows font size to be set dynamically exceeding the amount set in `soft_max_font_atlases`.
/// Note each font size has to be generated which can have a strong performance impact.
pub allow_dynamic_font_size: bool,
}
impl Default for TextSettings {
fn default() -> Self {
Self {
soft_max_font_atlases: NonZeroUsize::new(16).unwrap(),
allow_dynamic_font_size: false,
}
}
}
/// This resource tracks whether or not a warning has been emitted due to the number
/// of font atlases exceeding the [`TextSettings::soft_max_font_atlases`] setting.
#[derive(Resource, Default)]
pub struct FontAtlasWarning {
warned: bool,
}
/// Text is rendered for two different view projections, a [`Text2dBundle`] is rendered with a
/// `BottomToTop` y axis, while UI is rendered with a `TopToBottom` y axis. This matters for text because
/// the glyph positioning is different in either layout.
pub enum YAxisOrientation {
TopToBottom,
BottomToTop,
}
impl Plugin for TextPlugin {
fn build(&self, app: &mut App) {
app.init_asset::<Font>()
.register_type::<Text>()
.register_type::<Text2dBounds>()
.register_type::<TextSection>()
.register_type::<Vec<TextSection>>()
.register_type::<TextStyle>()
.register_type::<TextAlignment>()
.register_type::<BreakLineOn>()
.init_asset_loader::<FontLoader>()
.init_resource::<TextSettings>()
.init_resource::<FontAtlasWarning>()
.init_resource::<FontAtlasSets>()
.insert_resource(TextPipeline::default())
.add_systems(
PostUpdate,
(
update_text2d_layout
// Potential conflict: `Assets<Image>`
// In practice, they run independently since `bevy_render::camera_update_system`
// will only ever observe its own render target, and `update_text2d_layout`
// will never modify a pre-existing `Image` asset.
.ambiguous_with(CameraUpdateSystem),
font_atlas_set::remove_dropped_font_atlas_sets,
),
);
if let Ok(render_app) = app.get_sub_app_mut(RenderApp) {
render_app.add_systems(
ExtractSchedule,
extract_text2d_sprite.after(SpriteSystem::ExtractSprites),
);
}
#[cfg(feature = "default_font")]
load_internal_binary_asset!(
app,
Handle::default(),
"FiraMono-subset.ttf",
|bytes: &[u8], _path: String| { Font::try_from_bytes(bytes.to_vec()).unwrap() }
);
}
}