# Objective
Co-Authored-By: davier
[bricedavier@gmail.com](mailto:bricedavier@gmail.com)
Fixes#3576.
Adds a `resources` field in scene serialization data to allow
de/serializing resources that have reflection enabled.
## Solution
Most of this code is taken from a previous closed PR:
https://github.com/bevyengine/bevy/pull/3580. Most of the credit goes to
@Davier , what I did was mostly getting it to work on the latest main
branch of Bevy, along with adding a few asserts in the currently
existing tests to be sure everything is working properly.
This PR changes the scene format to include resources in this way:
```
(
resources: {
// List of resources here, keyed by resource type name.
},
entities: [
// Previous scene format here
],
)
```
An example taken from the tests:
```
(
resources: {
"bevy_scene::serde::tests::MyResource": (
foo: 123,
),
},
entities: {
// Previous scene format here
},
)
```
For this, a `resources` fields has been added on the `DynamicScene` and
the `DynamicSceneBuilder` structs. The latter now also has a method
named `extract_resources` to properly extract the existing resources
registered in the local type registry, in a similar way to
`extract_entities`.
---
## Changelog
Added: Reflect resources registered in the type registry used by dynamic
scenes will now be properly de/serialized in scene data.
## Migration Guide
Since the scene format has been changed, the user may not be able to use
scenes saved prior to this PR due to the `resources` scene field being
missing. ~~To preserve backwards compatibility, I will try to make the
`resources` fully optional so that old scenes can be loaded without
issue.~~
## TODOs
- [x] I may have to update a few doc blocks still referring to dynamic
scenes as mere container of entities, since they now include resources
as well.
- [x] ~~I want to make the `resources` key optional, as specified in the
Migration Guide, so that old scenes will be compatible with this
change.~~ Since this would only be trivial for ron format, I think it
might be better to consider it in a separate PR/discussion to figure out
if it could be done for binary serialization too.
- [x] I suppose it might be a good idea to add a resources in the scene
example so that users will quickly notice they can serialize resources
just like entities.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Ability to use `ReflectComponent` methods in dynamic type contexts with no access to `&World`.
This problem occurred to me when wanting to apply reflected types to an entity where the `&World` reference was already consumed by query iterator leaving only `EntityMut`.
## Solution
- Remove redundant `EntityMut` or `EntityRef` lookup from `World` and `Entity` in favor of taking `EntityMut` directly in `ReflectComponentFns`.
- Added `RefectComponent::contains` to determine without panic whether `apply` can be used.
## Changelog
- Changed function signatures of `ReflectComponent` methods, `apply`, `remove`, `contains`, and `reflect`.
## Migration Guide
- Call `World::entity` before calling into the changed `ReflectComponent` methods, most likely user already has a `EntityRef` or `EntityMut` which was being queried redundantly.
# Objective
- Dynamic scene builder can build scenes without components, if they didn't have any matching the type registry
- Those entities are not really useful in the final `DynamicScene`
## Solution
- Add a method `remove_empty_entities` that will remove empty entities. It's not called by default when calling `build`, I'm not sure if that's a good idea or not.
# Objective
Fixes#6059, changing all incorrect occurrences of ``id`` in the ``entity`` module to ``index``:
* struct level documentation,
* ``id`` struct field,
* ``id`` method and its documentation.
## Solution
Renaming and verifying using CI.
Co-authored-by: Edvin Kjell <43633999+Edwox@users.noreply.github.com>
# Objective
Currently, `DynamicSceneBuilder` keeps track of entities via a `HashMap`. This has an unintended side-effect in that, when building the full `DynamicScene`, we aren't guaranteed any particular order.
In other words, inserting Entity A then Entity B can result in either `[A, B]` or `[B, A]`. This can be rather annoying when running tests on scenes generated via the builder as it will work sometimes but not other times. There's also the potential that this might unnecessarily clutter up VCS diffs for scene files (assuming they had an intentional order).
## Solution
Store `DynamicSceneBuilder`'s entities in a `Vec` rather than a `HashMap`.
---
## Changelog
* Stablized entity order in `DynamicSceneBuilder` (0.9.0-dev)
# Objective
- make it easier to build dynamic scenes
## Solution
- add a builder to create a dynamic scene from a world. it can extract an entity or an iterator of entities
- alternative to #6013, leaving the "hierarchy iteration" part to #6185 which does it better
- alternative to #6004
- using a builder makes it easier to chain several extractions
