 6f7d0e5725
			
		
	
	
		6f7d0e5725
		
			
		
	
	
	
	
		
			
			# Objective
Currently text is recomputed unnecessarily on any changes to its color,
which is extremely expensive.
## Solution
Split up `TextStyle` into two separate components `TextFont` and
`TextColor`.
## Testing
I added this system to `many_buttons`:
```rust
fn set_text_colors_changed(mut colors: Query<&mut TextColor>) {
    for mut text_color in colors.iter_mut() {
        text_color.set_changed();
    }
}
```
reports ~4fps on main, ~50fps with this PR.
## Migration Guide
`TextStyle` has been renamed to `TextFont` and its `color` field has
been moved to a separate component named `TextColor` which newtypes
`Color`.
		
	
			
		
			
				
	
	
		
			84 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			84 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! This example illustrates how to use `TextureAtlases` within ui
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| 
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| use bevy::{color::palettes::css::*, prelude::*, winit::WinitSettings};
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| 
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| fn main() {
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|     App::new()
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|         .add_plugins(DefaultPlugins.set(
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|             // This sets image filtering to nearest
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|             // This is done to prevent textures with low resolution (e.g. pixel art) from being blurred
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|             // by linear filtering.
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|             ImagePlugin::default_nearest(),
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|         ))
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|         // Only run the app when there is user input. This will significantly reduce CPU/GPU use.
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|         .insert_resource(WinitSettings::desktop_app())
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|         .add_systems(Startup, setup)
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|         .add_systems(Update, increment_atlas_index)
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|         .run();
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| }
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| 
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| fn setup(
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|     mut commands: Commands,
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|     asset_server: Res<AssetServer>,
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|     mut texture_atlases: ResMut<Assets<TextureAtlasLayout>>,
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| ) {
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|     // Camera
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|     commands.spawn(Camera2d);
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| 
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|     let text_font = TextFont::default();
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| 
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|     let texture_handle = asset_server.load("textures/rpg/chars/gabe/gabe-idle-run.png");
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|     let texture_atlas = TextureAtlasLayout::from_grid(UVec2::splat(24), 7, 1, None, None);
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|     let texture_atlas_handle = texture_atlases.add(texture_atlas);
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| 
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|     // root node
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|     commands
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|         .spawn(NodeBundle {
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|             style: Style {
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|                 width: Val::Percent(100.0),
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|                 height: Val::Percent(100.0),
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|                 flex_direction: FlexDirection::Column,
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|                 justify_content: JustifyContent::Center,
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|                 align_items: AlignItems::Center,
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|                 row_gap: Val::Px(text_font.font_size * 2.),
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|                 ..default()
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|             },
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|             ..default()
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|         })
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|         .with_children(|parent| {
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|             parent.spawn((
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|                 ImageBundle {
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|                     style: Style {
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|                         width: Val::Px(256.),
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|                         height: Val::Px(256.),
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|                         ..default()
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|                     },
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|                     image: UiImage::new(texture_handle),
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|                     background_color: BackgroundColor(ANTIQUE_WHITE.into()),
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|                     ..default()
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|                 },
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|                 TextureAtlas::from(texture_atlas_handle),
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|                 Outline::new(Val::Px(8.0), Val::ZERO, CRIMSON.into()),
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|             ));
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|             parent
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|                 .spawn((Text::new("press "), text_font.clone()))
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|                 .with_child((
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|                     TextSpan::new("space"),
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|                     TextColor(YELLOW.into()),
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|                     text_font.clone(),
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|                 ))
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|                 .with_child((TextSpan::new(" to advance frames"), text_font));
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|         });
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| }
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| 
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| fn increment_atlas_index(
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|     mut atlas_images: Query<&mut TextureAtlas>,
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|     keyboard: Res<ButtonInput<KeyCode>>,
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| ) {
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|     if keyboard.just_pressed(KeyCode::Space) {
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|         for mut atlas_image in &mut atlas_images {
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|             atlas_image.index = (atlas_image.index + 1) % 6;
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|         }
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|     }
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| }
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