Question

Should components with associated assets (e.g. Sprite + Handle<Image>) include their Handle as a field, or as a separate component on the same entity, or something else?

• Handle-as-field: May make certain generic systems impossible (see the asset_decompression example).
• Handle-as-component: May create ambiguity (see EnvironmentMapLight).

From the Discord discussion, this is blocked on Bevy scenes before a design decision can be made.

Status quo

Bevy's answer to this question is inconsistent (as of March 6th, 2024):

Component with a wrapped Handle field:

• UiImage::texture: Handle<Image>
• TextureAtlas::layout: Handle<TextureAtlasLayout>
• Skybox::image: Handle<Image>
• Mesh2dHandle::0: Handle<Mesh>
• SkinnedMesh::inverse_bindposes: Handle<SkinnedMeshInverseBindposes>
• Lightmap::image: Handle<Image>
• IrradianceVolume::voxels: Handle<Image>
• EnvironmentMapLight::diffuse_map: Handle<Image>
• EnvironmentMapLight::specular_map: Handle<Image>

Component with an associated Handle-as-component:

• Sprite + Handle<Image>
• more? hard to ripgrep for this

Bundle with a Handle-as-component field:

• SpriteBundle::texture: Handle<Image>
• SceneBundle::scene: Handle<Scene>
• DynamicSceneBundle::scene: Handle<DynamicScene>
• MaterialMesh2dBundle<M>::material: Handle<M>
• MaterialMeshBundle<M>::material: Handle<M>
• MaterialMeshBundle<M>::mesh: Handle<Mesh>
• MaterialNodeBundle<M>::material: Handle<M>
• AudioSourceBundle<Source>::source: Handle<Source>