Add some missed migration guides for 0.15 (#1846)

Co-authored-by: BD103 <[email protected]>

generate-release/README.md

@@ -15,7 +15,7 @@ To create issues for the `release-notes` subcommand, you need to pass the `--cre
 Before running the command, you'll need to generate a GitHub API token at <https://github.com/settings/tokens>. It's easier to use classic tokens.
 The token must have `repo` permissions to be able to open issues (and PRs) on your behalf.
 
-Then add it to a file called `.env` like so:
+Then add it to a file called `.env` (stored in the root `bevy-website` folder) like so:
 
 ```env
 GITHUB_TOKEN=token_string_copied_from_github

release-content/0.15/migration-guides/14387_Deprecate_is_playing_animation.md

@@ -0,0 +1 @@
+The user will just need to replace functions named `is_playing_animation` with `animation_is_playing`.

release-content/0.15/migration-guides/15482_bevy_reflect_Add_ReflectDeserializerProcessor.md

@@ -0,0 +1,51 @@
+(Since I added `P = ()`, I don’t think this is actually a breaking change anymore, but I’ll leave this in)
+
+`bevy_reflect`’s `ReflectDeserializer` and `TypedReflectDeserializer` now take a `ReflectDeserializerProcessor` as the type parameter `P`, which allows you to customize deserialization for specific types when they are found. However, the rest of the API surface (`new`) remains the same.
+<details>
+<summary>Original implementation</summary>
+
+Add `ReflectDeserializerProcessor`:
+
+```rs
+struct ReflectDeserializerProcessor {
+    pub can_deserialize: Box<dyn FnMut(&TypeRegistration) -> bool + 'p>,
+    pub deserialize: Box<
+        dyn FnMut(
+                &TypeRegistration,
+                &mut dyn erased_serde::Deserializer,
+            ) -> Result<Box<dyn PartialReflect>, erased_serde::Error>
+            + 'p,
+}
+```
+
+Along with `ReflectDeserializer::new_with_processor` and `TypedReflectDeserializer::new_with_processor`. This does not touch the public API of the existing `new` fns.
+
+This is stored as an `Option<&mut ReflectDeserializerProcessor>` on the deserializer and any of the private `-Visitor` structs, and when we attempt to deserialize a value, we first pass it through this processor.
+
+Also added a very comprehensive doc test to `ReflectDeserializerProcessor`, which is actually a scaled down version of the code for the `bevy_animation_graph` loader. This should give users a good motivating example for when and why to use this feature.
+
+__Why `Box<dyn ..>`?__
+
+When I originally implemented this, I added a type parameter to `ReflectDeserializer` to determine the processor used, with `()` being “no processor”. However when using this, I kept running into rustc errors where it failed to validate certain type bounds and led to overflows. I then switched to a dynamic dispatch approach.
+
+The dynamic dispatch should not be that expensive, nor should it be a performance regression, since it’s only used if there is `Some` processor. (Note: I have not benchmarked this, I am just speculating.) Also, it means that we don’t infect the rest of the code with an extra type parameter, which is nicer to maintain.
+
+__Why the `'p` on `ReflectDeserializerProcessor<'p>`?__
+
+Without a lifetime here, the `Box`es would automatically become `Box<dyn FnMut(..) + 'static>`. This makes them practically useless, since any local data you would want to pass in must then be `'static`. In the motivating example, you couldn’t pass in that `&mut LoadContext` to the function.
+
+This means that the `'p` infects the rest of the Visitor types, but this is acceptable IMO. This PR also elides the lifetimes in the `impl<'de> Visitor<'de> for -Visitor` blocks where possible.
+
+__Future possibilities__
+
+I think it’s technically possible to turn the processor into a trait, and make the deserializers generic over that trait. This would also open the door to an API like:
+
+```rs
+type Seed;
+
+fn seed_deserialize(&mut self, r: &TypeRegistration) -> Option<Self::Seed>;
+
+fn deserialize(&mut self, r: &TypeRegistration, d: &mut dyn erased_serde::Deserializer, s: Self::Seed) -> ...;
+```
+
+A similar processor system should also be added to the serialization side, but that’s for another PR. Ideally, both PRs will be in the same release, since one isn’t very useful without the other.

release-content/0.15/migration-guides/15754_Rename_AppWorldobserve_to_add_observer_EntityWorldMutobser.md

@@ -0,0 +1,6 @@
+Various observer methods have been renamed for clarity.
+
+- `App::observe` -> `App::add_observer`
+- `World::observe` -> `World::add_observer`
+- `Commands::observe` -> `Commands::add_observer`
+- `EntityWorldMut::observe_entity` -> `EntityWorldMut::observe`

release-content/0.15/migration-guides/16037_Use_enus_locale_for_typos.md

@@ -0,0 +1,9 @@
+The following methods or fields have been renamed from `*dependants*` to `*dependents*`.
+
+- `ProcessorAssetInfo::dependants`
+- `ProcessorAssetInfos::add_dependant`
+- `ProcessorAssetInfos::non_existent_dependants`
+- `AssetInfo::dependants_waiting_on_load`
+- `AssetInfo::dependants_waiting_on_recursive_dep_load`
+- `AssetInfos::loader_dependants`
+- `AssetInfos::remove_dependants_and_labels`

release-content/0.15/migration-guides/16069_Reduce_the_clusterable_object_UBO_size_below_16384_for_Web.md

@@ -0,0 +1 @@
+<!-- TODO -->

release-content/0.15/migration-guides/16072_Move_TextureAtlas_into_UiImage_and_remove_impl_Component_f.md

@@ -0,0 +1,32 @@
+Before:
+
+```rust
+commands.spawn((
+  UiImage::new(image),
+  TextureAtlas { index, layout },
+));
+```
+
+After:
+
+```rust
+commands.spawn(UiImage::from_atlas_image(image, TextureAtlas { index, layout }));
+```
+
+Before:
+
+```rust
+commands.spawn(UiImage {
+    texture: some_image,
+    ..default()
+})
+```
+
+After:
+
+```rust
+commands.spawn(UiImage {
+    image: some_image,
+    ..default()
+})
+```

release-content/0.15/migration-guides/16090_Adding_alpha_threshold_to_OrderIndependentTransparencySett.md

@@ -0,0 +1,13 @@
+If you previously explicitly initialized OrderIndependentTransparencySettings with your own `layer_count`, you will now have to add either a `..default()` statement or an explicit `alpha_threshold` value:
+
+```rust
+fn setup(mut commands: Commands) {
+    commands.spawn((
+        Camera3d::default(),
+        OrderIndependentTransparencySettings {
+            layer_count: 16,
+            ..default()
+        },
+    ));
+}
+```

release-content/0.15/migration-guides/16097_Remove_custom_rounding.md

@@ -0,0 +1 @@
+`UiSurface::get_layout` now also returns the final sizes before rounding. Call `.0` on the `Ok` result to get the previously returned `taffy::Layout` value.

release-content/0.15/migration-guides/16139_ReflectBundleremove_improvement.md

@@ -0,0 +1 @@
+If you don’t need the returned value from `remove`, discard it.

release-content/0.15/migration-guides/16163_Dont_reëxport_bevy_image_from_bevy_render.md

@@ -0,0 +1 @@
+Use `bevy_image` instead of `bevy_render::texture` items.

release-content/0.15/migration-guides/16222_Gamepad_improvements.md

@@ -0,0 +1,2 @@
+- `Gamepad` fields are now public.
+- Instead of using `Gamepad` delegates like `Gamepad::just_pressed`, call these methods directly on the fields.

release-content/0.15/migration-guides/16233_Use_Name_component_for_gamepad.md

@@ -0,0 +1,4 @@
+- `GamepadInfo` no longer exists:
+  - Name now accessible via `Name` component.
+  - Other information available on `Gamepad` component directly.
+  - `GamepadConnection::Connected` now stores all info fields directly.

release-content/0.15/migration-guides/16257_Remove_accesskit_reexport_from_bevy_a11y.md

@@ -0,0 +1,15 @@
+```diff
+# main.rs
+--    use bevy_a11y::{
+--        accesskit::{Node, Rect, Role},
+--        AccessibilityNode,
+--    };
+++    use bevy_a11y::AccessibilityNode;
+++    use accesskit::{Node, Rect, Role};
+
+# Cargo.toml
+++    accesskit = "0.17"
+```
+
+- Users will need to add `accesskit = "0.17"` to the dependencies section of their `Cargo.toml` file and update their `accesskit` use statements to come directly from the external crate instead of `bevy_a11y`.
+- Make sure to keep the versions of `accesskit` aligned with the versions Bevy uses.

release-content/0.15/migration-guides/16269_Make_ComponentTicks_field_public.md

@@ -0,0 +1 @@
+- Instead of using `ComponentTicks::last_changed_tick` and `ComponentTicks::added_tick` methods, access fields directly.

release-content/0.15/migration-guides/16271_UiImage__ImageNode_UiImageSize__ImageNodeSize.md

@@ -0,0 +1,11 @@
+Before:
+
+```rust
+commands.spawn(UiImage::new(image));
+```
+
+After:
+
+```rust
+commands.spawn(ImageNode::new(image));
+```

release-content/0.15/migration-guides/16301_Expose_Pipeline_Compilation_Zero_Initialize_Workgroup_Memo.md

@@ -0,0 +1 @@
+- add `zero_initialize_workgroup_memory: false,` to `ComputePipelineDescriptor` or `RenderPipelineDescriptor` structs to preserve 0.14 functionality, add `zero_initialize_workgroup_memory: true,` to restore bevy 0.13 functionality.

release-content/0.15/migration-guides/16327_Rename_Rot2angle_between_to_Rot2angle_to.md

@@ -0,0 +1 @@
+`Rot2::angle_between` has been deprecated, use `Rot2::angle_to` instead, the semantics of `Rot2::angle_between` will change in the future.

release-content/0.15/migration-guides/16375_Only_use_physical_coords_internally_in_bevy_ui.md

@@ -0,0 +1,2 @@
+`ComputedNode`’s fields and methods now use physical coordinates.
+`ComputedNode` has a new field `inverse_scale_factor`. Multiplying the physical coordinates by the `inverse_scale_factor` will give the logical values.

release-content/0.15/migration-guides/16405_Bind_only_the_written_parts_of_storage_buffers.md

@@ -0,0 +1 @@
+- Fixed a bug with StorageBuffer and DynamicStorageBuffer binding data from the previous frame(s) due to caching GPU buffers between frames.

release-content/0.15/migration-guides/16468_Only_use_the_AABB_center_for_mesh_visibility_range_testing.md

@@ -0,0 +1 @@
+- The `VisibilityRange` component now has an extra field, `use_aabb`. Generally, you can safely set it to false.

release-content/0.15/migration-guides/16473_Add_flags_to_SpritePlugin_and_UiPlugin_to_allow_disabling_.md

@@ -0,0 +1,2 @@
+- `UiPlugin` now contains an extra `add_picking` field if `bevy_ui_picking_backend` is enabled.
+- `SpritePlugin` is no longer a unit struct, and has one field if `bevy_sprite_picking_backend` is enabled (otherwise no fields).

release-content/0.15/migration-guides/16481_cleanup_bevy_renderlibrs.md

@@ -0,0 +1 @@
+`RenderCreation::Manual` variant fields are now wrapped in a struct called `RenderResources`