bevy/examples/ui/font_atlas_debug.rs
Mark Schmale 1ba7429371 Doc/module style doc blocks for examples (#4438)
# Objective

Provide a starting point for #3951, or a partial solution. 
Providing a few comment blocks to discuss, and hopefully find better one in the process. 

## Solution

Since I am pretty new to pretty much anything in this context, I figured I'd just start with a draft for some file level doc blocks. For some of them I found more relevant details (or at least things I considered interessting), for some others there is less. 

## Changelog

- Moved some existing comments from main() functions in the 2d examples to the file header level
- Wrote some more comment blocks for most other 2d examples

TODO: 
- [x] 2d/sprite_sheet, wasnt able to come up with something good yet 
- [x] all other example groups...


Also: Please let me know if the commit style is okay, or to verbose. I could certainly squash these things, or add more details if needed. 
I also hope its okay to raise this PR this early, with just a few files changed. Took me long enough and I dont wanted to let it go to waste because I lost motivation to do the whole thing. Additionally I am somewhat uncertain over the style and contents of the commets. So let me know what you thing please.
2022-05-16 13:53:20 +00:00

96 lines
2.8 KiB
Rust

//! This example illustrates how `FontAtlas`'s are populated.
//! Bevy uses `FontAtlas`'s under the hood to optimize text rendering.
use bevy::{prelude::*, text::FontAtlasSet};
fn main() {
App::new()
.init_resource::<State>()
.insert_resource(ClearColor(Color::BLACK))
.add_plugins(DefaultPlugins)
.add_startup_system(setup)
.add_system(text_update_system)
.add_system(atlas_render_system)
.run();
}
struct State {
atlas_count: u32,
handle: Handle<Font>,
timer: Timer,
}
impl Default for State {
fn default() -> Self {
Self {
atlas_count: 0,
handle: Handle::default(),
timer: Timer::from_seconds(0.05, true),
}
}
}
fn atlas_render_system(
mut commands: Commands,
mut state: ResMut<State>,
font_atlas_sets: Res<Assets<FontAtlasSet>>,
texture_atlases: Res<Assets<TextureAtlas>>,
) {
if let Some(set) = font_atlas_sets.get(&state.handle.as_weak::<FontAtlasSet>()) {
if let Some((_size, font_atlas)) = set.iter().next() {
let x_offset = state.atlas_count as f32;
if state.atlas_count == font_atlas.len() as u32 {
return;
}
let texture_atlas = texture_atlases
.get(&font_atlas[state.atlas_count as usize].texture_atlas)
.unwrap();
state.atlas_count += 1;
commands.spawn_bundle(ImageBundle {
image: texture_atlas.texture.clone().into(),
style: Style {
position_type: PositionType::Absolute,
position: UiRect {
top: Val::Px(0.0),
left: Val::Px(512.0 * x_offset),
..default()
},
..default()
},
..default()
});
}
}
}
fn text_update_system(mut state: ResMut<State>, time: Res<Time>, mut query: Query<&mut Text>) {
if state.timer.tick(time.delta()).finished() {
for mut text in query.iter_mut() {
let c = rand::random::<u8>() as char;
if !text.sections[0].value.contains(c) {
text.sections[0].value.push(c);
}
}
state.timer.reset();
}
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>, mut state: ResMut<State>) {
let font_handle = asset_server.load("fonts/FiraSans-Bold.ttf");
state.handle = font_handle.clone();
commands.spawn_bundle(UiCameraBundle::default());
commands.spawn_bundle(TextBundle {
text: Text::with_section(
"a",
TextStyle {
font: font_handle,
font_size: 60.0,
color: Color::YELLOW,
},
Default::default(),
),
..default()
});
}