Rim effect outline

Capstone project that recreates rim effect outline. This project is experiment with Bevy rust engine for learning purpose. Can be used as lib for adding rim effect outline material extension.

Run demo example where you can change:

• width(power) - press W + mouse scroll;
• time scale - press T + mouse scroll;
• (const width)/(time dependency width) - press R (don`t hold button, otherwise state will change with high frequency).

Build demo

make demo

or

cargo run --example demo

How use rim effect outline in own project?

Demo example describe how can be integrated rim effect outline in own project.

Base tips to add rim effect outline:

1. Add Outline<RimEffect> as MaterialExtension(link to code):

    impl Plugin for OutlinesPlugin 
    {
        fn build(&self, app: &mut App)
        {
            add_outline::< RimEffect >( app );
        }
    }
    
    fn add_outline< O : OutlineLabel >( app : &mut App )
    where 
        Outline< O > : MaterialExtension,
        MaterialPlugin::< ExtendedMaterial< StandardMaterial, Outline< O > > >: Plugin
    {
        O::load_shader(app);

        app.add_plugins(
                MaterialPlugin::< ExtendedMaterial< StandardMaterial, Outline< O > > >::default( )
            )
            .register_type::< Outline< O > >();
    }

2. Add systems for changing Outline<RimEffect> parameters (link to code):

    impl Plugin for OutlinesPlugin 
    {
        fn build(&self, app: &mut App)
        {
            add_outline::< RimEffect >( app );
        }
    }
    
    fn add_outline< O : OutlineLabel >( app : &mut App )
    where 
        Outline< O > : MaterialExtension,
        MaterialPlugin::< ExtendedMaterial< StandardMaterial, Outline< O > > >: Plugin
    {
        app.add_systems( Update, ( 
                update_material_time::< O >  
            ));
    }

    fn update_material_time< O : OutlineLabel >(
        time : Res< Time >,
        mut materials : ResMut< Assets< ExtendedMaterial< StandardMaterial, Outline< O > > > >,
    )
    where Outline< O > : MaterialExtension{
        for ( _, material ) in materials.iter_mut( ) {
            material.extension.add_time( material.extension.time_scale * time.delta_seconds( ) );
        }
    }

3. Add Outline<RimEffect> extension to MaterialExtension when entity spawned (link to code):

    fn spawn_shapes(
        mut commands: Commands,
        mut materials: ResMut<Assets<ExtendedMaterial< StandardMaterial, Outline< RimEffect > >>>,
        shapes: Res<Shapes>
    ){
        for shape in shapes.0.iter( )
        {
            let Shape{ transform, shape } = shape;
            commands.spawn(( 
                MaterialMeshBundle
                {
                    mesh: shape.clone(),
                    transform: *transform,
                    material : materials.add( 
                        ExtendedMaterial {
                            base: StandardMaterial { 
                                ..default()
                            },
                            extension : Outline::< RimEffect >::default( )
                        } ),    
                    ..default( )
                },
                RimEffect::default( ),
            ));
        }
    }