Trait bevy_render::extract_component::ExtractComponent

pub trait ExtractComponent: Component {
    type Query: WorldQuery + ReadOnlyWorldQuery;
    type Filter: WorldQuery + ReadOnlyWorldQuery;
    type Out: Bundle;

    // Required method
    fn extract_component(item: QueryItem<'_, Self::Query>) -> Option<Self::Out>;
}

Describes how a component gets extracted for rendering.

Therefore the component is transferred from the “app world” into the “render world” in the ExtractSchedule step.

Required Associated Types

type Query: WorldQuery + ReadOnlyWorldQuery

ECS WorldQuery to fetch the components to extract.

type Filter: WorldQuery + ReadOnlyWorldQuery

Filters the entities with additional constraints.

type Out: Bundle

The output from extraction.

Returning None based on the queried item can allow early optimization, for example if there is an enabled: bool field on Self, or by only accepting values within certain thresholds.

The output may be different from the queried component. This can be useful for example if only a subset of the fields are useful in the render world.

Out has a Bundle trait bound instead of a Component trait bound in order to allow use cases such as tuples of components as output.

Required Methods

fn extract_component(item: QueryItem<'_, Self::Query>) -> Option<Self::Out>

Defines how the component is transferred into the “render world”.

Implementations on Foreign Types

impl<T: Asset> ExtractComponent for Handle<T>

type Query = &'static Handle<T>

type Filter = ()

type Out = Handle<T>

fn extract_component(handle: QueryItem<'_, Self::Query>) -> Option<Self::Out>

Implementors