feature gate picking backends (#15369)

# Objective

Fixes #15306

## Solution

- Add feature gate on the module and the place where each one is used
- Declare the features and make them default

## Testing

- CI

Cargo.toml

@@ -68,6 +68,8 @@ default = [
   "bevy_core_pipeline",
   "bevy_pbr",
   "bevy_picking",
+  "bevy_sprite_picking_backend",
+  "bevy_ui_picking_backend",
   "bevy_gltf",
   "bevy_render",
   "bevy_sprite",
@@ -87,6 +89,12 @@ default = [
   "sysinfo_plugin",
 ]
 
+# Provides an implementation for picking sprites
+bevy_sprite_picking_backend = ["bevy_picking"]
+
+# Provides an implementation for picking ui
+bevy_ui_picking_backend = ["bevy_picking"]
+
 # Force dynamic linking, which improves iterative compile times
 dynamic_linking = ["dep:bevy_dylib", "bevy_internal/dynamic_linking"]
 
@@ -141,6 +149,7 @@ bevy_sprite = [
   "bevy_render",
   "bevy_core_pipeline",
   "bevy_color",
+  "bevy_sprite_picking_backend",
 ]
 
 # Provides text functionality
@@ -153,6 +162,7 @@ bevy_ui = [
   "bevy_text",
   "bevy_sprite",
   "bevy_color",
+  "bevy_ui_picking_backend",
 ]
 
 # winit window and input backend
@@ -3459,12 +3469,14 @@ wasm = true
 name = "sprite_picking"
 path = "examples/picking/sprite_picking.rs"
 doc-scrape-examples = true
+required-features = ["bevy_sprite_picking_backend"]
 
 [package.metadata.example.sprite_picking]
 name = "Sprite Picking"
 description = "Demonstrates picking sprites and sprite atlases"
 category = "Picking"
 wasm = true
+required-features = ["bevy_sprite_picking_backend"]
 
 [[example]]
 name = "animation_masks"

crates/bevy_sprite/Cargo.toml

@@ -9,7 +9,8 @@ license = "MIT OR Apache-2.0"
 keywords = ["bevy"]
 
 [features]
-bevy_picking = ["dep:bevy_picking", "dep:bevy_window"]
+default = ["bevy_sprite_picking_backend"]
+bevy_sprite_picking_backend = ["bevy_picking", "bevy_window"]
 webgl = []
 webgpu = []
 

crates/bevy_sprite/src/lib.rs

@@ -11,7 +11,7 @@
 mod bundle;
 mod dynamic_texture_atlas_builder;
 mod mesh2d;
-#[cfg(feature = "bevy_picking")]
+#[cfg(feature = "bevy_sprite_picking_backend")]
 mod picking_backend;
 mod render;
 mod sprite;
@@ -134,7 +134,7 @@ impl Plugin for SpritePlugin {
                 ),
             );
 
-        #[cfg(feature = "bevy_picking")]
+        #[cfg(feature = "bevy_sprite_picking_backend")]
         app.add_plugins(picking_backend::SpritePickingBackend);
 
         if let Some(render_app) = app.get_sub_app_mut(RenderApp) {

crates/bevy_ui/Cargo.toml

@@ -40,9 +40,9 @@ nonmax = "0.5"
 smallvec = "1.11"
 
 [features]
+default = ["bevy_ui_picking_backend"]
 serialize = ["serde", "smallvec/serde", "bevy_math/serialize"]
-bevy_picking = ["dep:bevy_picking"]
-
+bevy_ui_picking_backend = ["bevy_picking"]
 
 [lints]
 workspace = true

crates/bevy_ui/src/lib.rs

@@ -17,7 +17,7 @@ pub mod ui_material;
 pub mod update;
 pub mod widget;
 
-#[cfg(feature = "bevy_picking")]
+#[cfg(feature = "bevy_ui_picking_backend")]
 pub mod picking_backend;
 
 use bevy_derive::{Deref, DerefMut};
@@ -194,7 +194,7 @@ impl Plugin for UiPlugin {
 
         build_ui_render(app);
 
-        #[cfg(feature = "bevy_picking")]
+        #[cfg(feature = "bevy_ui_picking_backend")]
         app.add_plugins(picking_backend::UiPickingBackend);
     }
 

docs/cargo_features.md

@@ -26,9 +26,11 @@ The default feature set enables most of the expected features of a game engine,
 |bevy_render|Provides rendering functionality|
 |bevy_scene|Provides scene functionality|
 |bevy_sprite|Provides sprite functionality|
+|bevy_sprite_picking_backend|Provides an implementation for picking sprites|
 |bevy_state|Enable built in global state machines|
 |bevy_text|Provides text functionality|
 |bevy_ui|A custom ECS-driven UI framework|
+|bevy_ui_picking_backend|Provides an implementation for picking ui|
 |bevy_winit|winit window and input backend|
 |default_font|Include a default font, containing only ASCII characters, at the cost of a 20kB binary size increase|
 |hdr|HDR image format support|