# 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>