# Objective The `ui_material` recently gained a harsh red background via #15898. I'm assuming this was added for testing and forgotten about. https://pixel-eagle.com/project/b25a040a-a980-4602-b90c-d480ab84076d/run/5268/compare/5259?screenshot=UI%20(User%20Interface)/ui_material.png ## Solution Remove the red background ## Testing `cargo run --example ui_material`
		
			
				
	
	
		
			97 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			97 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
//! Demonstrates the use of [`UiMaterials`](UiMaterial) and how to change material values
 | 
						|
 | 
						|
use bevy::{prelude::*, reflect::TypePath, render::render_resource::*};
 | 
						|
 | 
						|
/// This example uses a shader source file from the assets subdirectory
 | 
						|
const SHADER_ASSET_PATH: &str = "shaders/custom_ui_material.wgsl";
 | 
						|
 | 
						|
fn main() {
 | 
						|
    App::new()
 | 
						|
        .add_plugins(DefaultPlugins)
 | 
						|
        .add_plugins(UiMaterialPlugin::<CustomUiMaterial>::default())
 | 
						|
        .add_systems(Startup, setup)
 | 
						|
        .add_systems(Update, animate)
 | 
						|
        .run();
 | 
						|
}
 | 
						|
 | 
						|
fn setup(
 | 
						|
    mut commands: Commands,
 | 
						|
    mut ui_materials: ResMut<Assets<CustomUiMaterial>>,
 | 
						|
    asset_server: Res<AssetServer>,
 | 
						|
) {
 | 
						|
    // Camera so we can see UI
 | 
						|
    commands.spawn(Camera2d);
 | 
						|
 | 
						|
    commands
 | 
						|
        .spawn(Node {
 | 
						|
            width: Val::Percent(100.0),
 | 
						|
            height: Val::Percent(100.0),
 | 
						|
            align_items: AlignItems::Center,
 | 
						|
            justify_content: JustifyContent::Center,
 | 
						|
            ..default()
 | 
						|
        })
 | 
						|
        .with_children(|parent| {
 | 
						|
            let banner_scale_factor = 0.5;
 | 
						|
            parent.spawn((
 | 
						|
                MaterialNode(ui_materials.add(CustomUiMaterial {
 | 
						|
                    color: LinearRgba::WHITE.to_f32_array().into(),
 | 
						|
                    slider: 0.5,
 | 
						|
                    color_texture: asset_server.load("branding/banner.png"),
 | 
						|
                    border_color: LinearRgba::WHITE.to_f32_array().into(),
 | 
						|
                })),
 | 
						|
                Node {
 | 
						|
                    position_type: PositionType::Absolute,
 | 
						|
                    width: Val::Px(905.0 * banner_scale_factor),
 | 
						|
                    height: Val::Px(363.0 * banner_scale_factor),
 | 
						|
                    border: UiRect::all(Val::Px(10.)),
 | 
						|
                    ..default()
 | 
						|
                },
 | 
						|
            ));
 | 
						|
        });
 | 
						|
}
 | 
						|
 | 
						|
#[derive(AsBindGroup, Asset, TypePath, Debug, Clone)]
 | 
						|
struct CustomUiMaterial {
 | 
						|
    /// Color multiplied with the image
 | 
						|
    #[uniform(0)]
 | 
						|
    color: Vec4,
 | 
						|
    /// Represents how much of the image is visible
 | 
						|
    /// Goes from 0 to 1
 | 
						|
    #[uniform(1)]
 | 
						|
    slider: f32,
 | 
						|
    /// Image used to represent the slider
 | 
						|
    #[texture(2)]
 | 
						|
    #[sampler(3)]
 | 
						|
    color_texture: Handle<Image>,
 | 
						|
    /// Color of the image's border
 | 
						|
    #[uniform(4)]
 | 
						|
    border_color: Vec4,
 | 
						|
}
 | 
						|
 | 
						|
impl UiMaterial for CustomUiMaterial {
 | 
						|
    fn fragment_shader() -> ShaderRef {
 | 
						|
        SHADER_ASSET_PATH.into()
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
// Fills the slider slowly over 2 seconds and resets it
 | 
						|
// Also updates the color of the image to a rainbow color
 | 
						|
fn animate(
 | 
						|
    mut materials: ResMut<Assets<CustomUiMaterial>>,
 | 
						|
    q: Query<&MaterialNode<CustomUiMaterial>>,
 | 
						|
    time: Res<Time>,
 | 
						|
) {
 | 
						|
    let duration = 2.0;
 | 
						|
    for handle in &q {
 | 
						|
        if let Some(material) = materials.get_mut(handle) {
 | 
						|
            // rainbow color effect
 | 
						|
            let new_color = Color::hsl((time.elapsed_secs() * 60.0) % 360.0, 1., 0.5);
 | 
						|
            let border_color = Color::hsl((time.elapsed_secs() * 60.0) % 360.0, 0.75, 0.75);
 | 
						|
            material.color = new_color.to_linear().to_vec4();
 | 
						|
            material.slider =
 | 
						|
                ((time.elapsed_secs() % (duration * 2.0)) - duration).abs() / duration;
 | 
						|
            material.border_color = border_color.to_linear().to_vec4();
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 |