Commit Graph

99 Commits

Author SHA1 Message Date
Carter Anderson
9666a7e688 Rename bevy_platform_support to bevy_platform (#18813)
The goal of `bevy_platform_support` is to provide a set of platform
agnostic APIs, alongside platform-specific functionality. This is a high
traffic crate (providing things like HashMap and Instant). Especially in
light of https://github.com/bevyengine/bevy/discussions/18799, it
deserves a friendlier / shorter name.

Given that it hasn't had a full release yet, getting this change in
before Bevy 0.16 makes sense.

- Rename `bevy_platform_support` to `bevy_platform`.
2025-04-14 22:45:27 +02:00
François Mockers
c4b3d75b46 Release 0.16.0-rc.4 2025-04-11 09:12:55 +02:00
Zachary Harrold
c5365509bf Allow partial support for bevy_log in no_std (#18782)
- Fixes #18781

- Moved `LogPlugin` into its own file gated behind a new `tracing`
feature.
- Used `log` instead of `tracing` where possible.
- Exposed a new `tracing` feature in `bevy` which enables
`bevy_log/tracing`.
- Gated `LogPlugin` from `DefaultPlugins` on `tracing` feature.

- CI

---

- If you were previously using `bevy_log` with default features
disabled, enable the new `std` and `tracing` features.
- If you were using `bevy` with the default features disabled, enable
the new `tracing` feature.

Almost all of the diffs in this PR come from moving `LogPlugin` into its
own file. This just makes the PR less noisy, since the alternative is
excessive `#[cfg(feature = "tracing")]` directives all over the plugin.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2025-04-11 09:03:12 +02:00
François Mockers
bdfd7a3443 Release 0.16.0-rc.3 2025-03-31 23:07:43 +02:00
François Mockers
1f44b56310 Release 0.16.0-rc.2 2025-03-26 19:18:20 +01:00
Greeble
7e45e8635c Reduce dependencies on bevy_render by preferring bevy_mesh imports (#18437)
Reduce dependencies on `bevy_render` by preferring `bevy_mesh` imports
over `bevy_render` re-exports.

```diff
- use bevy_render::mesh::Mesh;
+ use bevy_mesh::Mesh;
```

This is intended to help with #18423 (render crate restructure). Affects
`bevy_gltf`, `bevy_animation` and `bevy_picking`.

As part of #18423, I'm assuming there'll be a push to make crates less
dependent on the big render crates. This PR seemed like a small and safe
step along that path - it only changes imports and makes the `bevy_mesh`
crate dependency explicit in `Cargo.toml`. Any remaining dependencies on
`bevy_render` are true dependencies.

```
cargo run --example testbed_3d
cargo run --example mesh_picking
```
2025-03-25 22:45:39 +01:00
François Mockers
920515adab Release 0.16.0-rc.1 2025-03-18 21:48:22 +01:00
Zachary Harrold
cc69fdd0c6
Add no_std support to bevy (#17955)
# Objective

- Fixes #15460 (will open new issues for further `no_std` efforts)
- Supersedes #17715

## Solution

- Threaded in new features as required
- Made certain crates optional but default enabled
- Removed `compile-check-no-std` from internal `ci` tool since GitHub CI
can now simply check `bevy` itself now
- Added CI task to check `bevy` on `thumbv6m-none-eabi` to ensure
`portable-atomic` support is still valid [^1]

[^1]: This may be controversial, since it could be interpreted as
implying Bevy will maintain support for `thumbv6m-none-eabi` going
forward. In reality, just like `x86_64-unknown-none`, this is a
[canary](https://en.wiktionary.org/wiki/canary_in_a_coal_mine) target to
make it clear when `portable-atomic` no longer works as intended (fixing
atomic support on atomically challenged platforms). If a PR comes
through and makes supporting this class of platforms impossible, then
this CI task can be removed. I however wager this won't be a problem.

## Testing

- CI

---

## Release Notes

Bevy now has support for `no_std` directly from the `bevy` crate.

Users can disable default features and enable a new `default_no_std`
feature instead, allowing `bevy` to be used in `no_std` applications and
libraries.

```toml
# Bevy for `no_std` platforms
bevy = { version = "0.16", default-features = false, features = ["default_no_std"] }
```

`default_no_std` enables certain required features, such as `libm` and
`critical-section`, and as many optional crates as possible (currently
just `bevy_state`). For atomically-challenged platforms such as the
Raspberry Pi Pico, `portable-atomic` will be used automatically.

For library authors, we recommend depending on `bevy` with
`default-features = false` to allow `std` and `no_std` users to both
depend on your crate. Here are some recommended features a library crate
may want to expose:

```toml
[features]
# Most users will be on a platform which has `std` and can use the more-powerful `async_executor`.
default = ["std", "async_executor"]

# Features for typical platforms.
std = ["bevy/std"]
async_executor = ["bevy/async_executor"]

# Features for `no_std` platforms.
libm = ["bevy/libm"]
critical-section = ["bevy/critical-section"]

[dependencies]
# We disable default features to ensure we don't accidentally enable `std` on `no_std` targets, for example. 
bevy = { version = "0.16", default-features = false }
```

While this is verbose, it gives the maximum control to end-users to
decide how they wish to use Bevy on their platform.

We encourage library authors to experiment with `no_std` support. For
libraries relying exclusively on `bevy` and no other dependencies, it
may be as simple as adding `#![no_std]` to your `lib.rs` and exposing
features as above! Bevy can also provide many `std` types, such as
`HashMap`, `Mutex`, and `Instant` on all platforms. See
`bevy::platform_support` for details on what's available out of the box!

## Migration Guide

- If you were previously relying on `bevy` with default features
disabled, you may need to enable the `std` and `async_executor`
features.
- `bevy_reflect` has had its `bevy` feature removed. If you were relying
on this feature, simply enable `smallvec` and `smol_str` instead.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-03-07 03:39:46 +00:00
dependabot[bot]
cf18c346d8
Update itertools requirement from 0.13 to 0.14 (#18128)
Updates the requirements on
[itertools](https://github.com/rust-itertools/itertools) to permit the
latest version.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/rust-itertools/itertools/blob/master/CHANGELOG.md">itertools's
changelog</a>.</em></p>
<blockquote>
<h2>0.14.0</h2>
<h3>Breaking</h3>
<ul>
<li>Increased MSRV to 1.63.0 (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/960">#960</a>)</li>
<li>Removed generic parameter from <code>cons_tuples</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/988">#988</a>)</li>
</ul>
<h3>Added</h3>
<ul>
<li>Added <code>array_combinations</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/991">#991</a>)</li>
<li>Added <code>k_smallest_relaxed</code> and variants (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/925">#925</a>)</li>
<li>Added <code>next_array</code> and <code>collect_array</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/560">#560</a>)</li>
<li>Implemented <code>DoubleEndedIterator</code> for
<code>FilterOk</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/948">#948</a>)</li>
<li>Implemented <code>DoubleEndedIterator</code> for
<code>FilterMapOk</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/950">#950</a>)</li>
</ul>
<h3>Changed</h3>
<ul>
<li>Allow <code>Q: ?Sized</code> in <code>Itertools::contains</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/971">#971</a>)</li>
<li>Improved hygiene of <code>chain!</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/943">#943</a>)</li>
<li>Improved <code>into_group_map_by</code> documentation (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/1000">#1000</a>)</li>
<li>Improved <code>tree_reduce</code> documentation (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/955">#955</a>)</li>
<li>Improved discoverability of <code>merge_join_by</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/966">#966</a>)</li>
<li>Improved discoverability of <code>take_while_inclusive</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/972">#972</a>)</li>
<li>Improved documentation of <code>find_or_last</code> and
<code>find_or_first</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/984">#984</a>)</li>
<li>Prevented exponentially large type sizes in
<code>tuple_combinations</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/945">#945</a>)</li>
<li>Added <code>track_caller</code> attr for <code>asser_equal</code>
(<a
href="https://redirect.github.com/rust-itertools/itertools/issues/976">#976</a>)</li>
</ul>
<h3>Notable Internal Changes</h3>
<ul>
<li>Fixed clippy lints (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/956">#956</a>,
<a
href="https://redirect.github.com/rust-itertools/itertools/issues/987">#987</a>,
<a
href="https://redirect.github.com/rust-itertools/itertools/issues/1008">#1008</a>)</li>
<li>Addressed warnings within doctests (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/964">#964</a>)</li>
<li>CI: Run most tests with miri (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/961">#961</a>)</li>
<li>CI: Speed up &quot;cargo-semver-checks&quot; action (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/938">#938</a>)</li>
<li>Changed an instance of <code>default_features</code> in
<code>Cargo.toml</code> to <code>default-features</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/985">#985</a>)</li>
</ul>
<h2>0.13.0</h2>
<h3>Breaking</h3>
<ul>
<li>Removed implementation of <code>DoubleEndedIterator</code> for
<code>ConsTuples</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/853">#853</a>)</li>
<li>Made <code>MultiProduct</code> fused and fixed on an empty iterator
(<a
href="https://redirect.github.com/rust-itertools/itertools/issues/835">#835</a>,
<a
href="https://redirect.github.com/rust-itertools/itertools/issues/834">#834</a>)</li>
<li>Changed <code>iproduct!</code> to return tuples for maxi one
iterator too (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/870">#870</a>)</li>
<li>Changed <code>PutBack::put_back</code> to return the old value (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/880">#880</a>)</li>
<li>Removed deprecated <code>repeat_call, Itertools::{foreach, step,
map_results, fold_results}</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/878">#878</a>)</li>
<li>Removed <code>TakeWhileInclusive::new</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/912">#912</a>)</li>
</ul>
<h3>Added</h3>
<ul>
<li>Added <code>Itertools::{smallest_by, smallest_by_key, largest,
largest_by, largest_by_key}</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/654">#654</a>,
<a
href="https://redirect.github.com/rust-itertools/itertools/issues/885">#885</a>)</li>
<li>Added <code>Itertools::tail</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/899">#899</a>)</li>
<li>Implemented <code>DoubleEndedIterator</code> for
<code>ProcessResults</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/910">#910</a>)</li>
<li>Implemented <code>Debug</code> for <code>FormatWith</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/931">#931</a>)</li>
<li>Added <code>Itertools::get</code> (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/891">#891</a>)</li>
</ul>
<h3>Changed</h3>
<ul>
<li>Deprecated <code>Itertools::group_by</code> (renamed
<code>chunk_by</code>) (<a
href="https://redirect.github.com/rust-itertools/itertools/issues/866">#866</a>,
<a
href="https://redirect.github.com/rust-itertools/itertools/issues/879">#879</a>)</li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="a015a68315"><code>a015a68</code></a>
Add <code>next_array</code> and <code>collect_array</code></li>
<li><a
href="a1213e1c81"><code>a1213e1</code></a>
Prepare v0.14.0 release</li>
<li><a
href="ff0c942b2e"><code>ff0c942</code></a>
fix clippy lints</li>
<li><a
href="f80883b8e0"><code>f80883b</code></a>
Fix into_group_map_by documentation errors</li>
<li><a
href="b793238ff1"><code>b793238</code></a>
Add track_caller for asser_equal</li>
<li><a
href="5d4056b643"><code>5d4056b</code></a>
<code>default_features</code> is deprecated - switch it to
<code>default-features</code></li>
<li><a
href="a447b68960"><code>a447b68</code></a>
doc for added trait</li>
<li><a
href="d0479b0807"><code>d0479b0</code></a>
&quot;nitpicks&quot;</li>
<li><a
href="35c78ce0bc"><code>35c78ce</code></a>
IndexMut -&gt; BorrowMut&lt;slice&gt;</li>
<li><a
href="deb53ba210"><code>deb53ba</code></a>
refactored to share code</li>
<li>Additional commits viewable in <a
href="https://github.com/rust-itertools/itertools/compare/v0.13.0...v0.14.0">compare
view</a></li>
</ul>
</details>
<br />


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2025-03-03 19:36:29 +00:00
Zachary Harrold
5241e09671
Upgrade to Rust Edition 2024 (#17967)
# Objective

- Fixes #17960

## Solution

- Followed the [edition upgrade
guide](https://doc.rust-lang.org/edition-guide/editions/transitioning-an-existing-project-to-a-new-edition.html)

## Testing

- CI

---

## Summary of Changes

### Documentation Indentation

When using lists in documentation, proper indentation is now linted for.
This means subsequent lines within the same list item must start at the
same indentation level as the item.

```rust
/* Valid */
/// - Item 1
///   Run-on sentence.
/// - Item 2
struct Foo;

/* Invalid */
/// - Item 1
///     Run-on sentence.
/// - Item 2
struct Foo;
```

### Implicit `!` to `()` Conversion

`!` (the never return type, returned by `panic!`, etc.) no longer
implicitly converts to `()`. This is particularly painful for systems
with `todo!` or `panic!` statements, as they will no longer be functions
returning `()` (or `Result<()>`), making them invalid systems for
functions like `add_systems`. The ideal fix would be to accept functions
returning `!` (or rather, _not_ returning), but this is blocked on the
[stabilisation of the `!` type
itself](https://doc.rust-lang.org/std/primitive.never.html), which is
not done.

The "simple" fix would be to add an explicit `-> ()` to system
signatures (e.g., `|| { todo!() }` becomes `|| -> () { todo!() }`).
However, this is _also_ banned, as there is an existing lint which (IMO,
incorrectly) marks this as an unnecessary annotation.

So, the "fix" (read: workaround) is to put these kinds of `|| -> ! { ...
}` closuers into variables and give the variable an explicit type (e.g.,
`fn()`).

```rust
// Valid
let system: fn() = || todo!("Not implemented yet!");
app.add_systems(..., system);

// Invalid
app.add_systems(..., || todo!("Not implemented yet!"));
```

### Temporary Variable Lifetimes

The order in which temporary variables are dropped has changed. The
simple fix here is _usually_ to just assign temporaries to a named
variable before use.

### `gen` is a keyword

We can no longer use the name `gen` as it is reserved for a future
generator syntax. This involved replacing uses of the name `gen` with
`r#gen` (the raw-identifier syntax).

### Formatting has changed

Use statements have had the order of imports changed, causing a
substantial +/-3,000 diff when applied. For now, I have opted-out of
this change by amending `rustfmt.toml`

```toml
style_edition = "2021"
```

This preserves the original formatting for now, reducing the size of
this PR. It would be a simple followup to update this to 2024 and run
`cargo fmt`.

### New `use<>` Opt-Out Syntax

Lifetimes are now implicitly included in RPIT types. There was a handful
of instances where it needed to be added to satisfy the borrow checker,
but there may be more cases where it _should_ be added to avoid
breakages in user code.

### `MyUnitStruct { .. }` is an invalid pattern

Previously, you could match against unit structs (and unit enum
variants) with a `{ .. }` destructuring. This is no longer valid.

### Pretty much every use of `ref` and `mut` are gone

Pattern binding has changed to the point where these terms are largely
unused now. They still serve a purpose, but it is far more niche now.

### `iter::repeat(...).take(...)` is bad

New lint recommends using the more explicit `iter::repeat_n(..., ...)`
instead.

## Migration Guide

The lifetimes of functions using return-position impl-trait (RPIT) are
likely _more_ conservative than they had been previously. If you
encounter lifetime issues with such a function, please create an issue
to investigate the addition of `+ use<...>`.

## Notes

- Check the individual commits for a clearer breakdown for what
_actually_ changed.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2025-02-24 03:54:47 +00:00
AlephCubed
45c266658b
Fixed bevy_image and bevy_gltf failing to compile with some features. (#17887)
Fixes #17290.
<details>
  <summary>Compilation errors before fix</summary>

`cargo clippy --tests --all-features --package bevy_image`:
```rust
error[E0061]: this function takes 7 arguments but 6 arguments were supplied
   --> crates/bevy_core_pipeline/src/tonemapping/mod.rs:451:5
    |
451 |     Image::from_buffer(
    |     ^^^^^^^^^^^^^^^^^^
...
454 |         bytes,
    |         ----- argument #1 of type `std::string::String` is missing
    |
note: associated function defined here
   --> /Users/josiahnelson/Desktop/Programming/Rust/bevy/crates/bevy_image/src/image.rs:930:12
    |
930 |     pub fn from_buffer(
    |            ^^^^^^^^^^^
help: provide the argument
    |
451 |     Image::from_buffer(/* std::string::String */, bytes, image_type, CompressedImageFormats::NONE, false, image_sampler, RenderAssetUsages::RENDER_WORLD)
    |                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
`cargo clippy --tests --all-features --package bevy_gltf`:
```rust
error[E0560]: struct `bevy_pbr::StandardMaterial` has no field named `specular_channel`
    --> crates/bevy_gltf/src/loader.rs:1343:13
     |
1343 |             specular_channel: specular.specular_channel,
     |             ^^^^^^^^^^^^^^^^ `bevy_pbr::StandardMaterial` does not have this field
     |
     = note: available fields are: `emissive_exposure_weight`, `diffuse_transmission`, `diffuse_transmission_channel`, `diffuse_transmission_texture`, `flip_normal_map_y` ... and 9 others

error[E0560]: struct `bevy_pbr::StandardMaterial` has no field named `specular_texture`
    --> crates/bevy_gltf/src/loader.rs:1345:13
     |
1345 |             specular_texture: specular.specular_texture,
     |             ^^^^^^^^^^^^^^^^ `bevy_pbr::StandardMaterial` does not have this field
     |
     = note: available fields are: `emissive_exposure_weight`, `diffuse_transmission`, `diffuse_transmission_channel`, `diffuse_transmission_texture`, `flip_normal_map_y` ... and 9 others

error[E0560]: struct `bevy_pbr::StandardMaterial` has no field named `specular_tint_channel`
    --> crates/bevy_gltf/src/loader.rs:1351:13
     |
1351 |             specular_tint_channel: specular.specular_color_channel,
     |             ^^^^^^^^^^^^^^^^^^^^^ `bevy_pbr::StandardMaterial` does not have this field
     |
     = note: available fields are: `emissive_exposure_weight`, `diffuse_transmission`, `diffuse_transmission_channel`, `diffuse_transmission_texture`, `flip_normal_map_y` ... and 9 others

error[E0560]: struct `bevy_pbr::StandardMaterial` has no field named `specular_tint_texture`
    --> crates/bevy_gltf/src/loader.rs:1353:13
     |
1353 |             specular_tint_texture: specular.specular_color_texture,
     |             ^^^^^^^^^^^^^^^^^^^^^ `bevy_pbr::StandardMaterial` does not have this field
     |
     = note: available fields are: `emissive_exposure_weight`, `diffuse_transmission`, `diffuse_transmission_channel`, `diffuse_transmission_texture`, `flip_normal_map_y` ... and 9 others
```
</details>
2025-02-17 05:10:13 +00:00
Patrick Walton
7774a624c2
Fix Maya-exported rigs by not trying to topologically sort glTF nodes. (#17641)
The code added in #14343 seems to be trying to ensure that a `Handle`
for each glTF node exists by topologically sorting the directed graph of
glTF nodes containing edges from parent to child and from skin to joint.
Unfortunately, such a graph can contain cycles, as there's no guarantee
that joints are descendants of nodes with the skin. In particular, glTF
exported from Maya using the popular babylon.js export plugin create
skins attached to nodes that animate their parent nodes. This was
causing the topological sort code to enter an infinite loop.

Assuming that the intent of the topological sort is indeed to ensure
that `Handle`s exist for each glTF node before populating them, there's
a better mechanism for this: `LoadContext::get_label_handle`. This is
the documented way to obtain a handle for a node before populating it,
obviating the need for a topological sort. This patch replaces the
topological sort with a pre-pass that uses
`LoadContext::get_label_handle` to get handles for each `Node` before
populating them. This fixes the problem with Maya rigs, in addition to
making the code simpler and faster.
2025-02-02 13:53:55 +00:00
Patrick Walton
1c765c9ae7
Add support for specular tints and maps per the KHR_materials_specular glTF extension. (#14069)
This commit allows specular highlights to be tinted with a color and for
the reflectance and color tint values to vary across a model via a pair
of maps. The implementation follows the [`KHR_materials_specular`] glTF
extension. In order to reduce the number of samplers and textures in the
default `StandardMaterial` configuration, the maps are gated behind the
`pbr_specular_textures` Cargo feature.

Specular tinting is currently unsupported in the deferred renderer,
because I didn't want to bloat the deferred G-buffers. A possible fix
for this in the future would be to make the G-buffer layout more
configurable, so that specular tints could be supported on an opt-in
basis. As an alternative, Bevy could force meshes with specular tints to
render in forward mode. Both of these solutions require some more
design, so I consider them out of scope for now.

Note that the map is a *specular* map, not a *reflectance* map. In Bevy
and Filament terms, the reflectance values in the specular map range
from [0.0, 0.5], rather than [0.0, 1.0]. This is an unfortunate
[`KHR_materials_specular`] specification requirement that stems from the
fact that glTF is specified in terms of a specular strength model, not
the reflectance model that Filament and Bevy use. A workaround, which is
noted in the `StandardMaterial` documentation, is to set the
`reflectance` value to 2.0, which spreads the specular map range from
[0.0, 1.0] as normal.

The glTF loader has been updated to parse the [`KHR_materials_specular`]
extension. Note that, unless the non-default `pbr_specular_textures` is
supplied, the maps are ignored. The `specularFactor` value is applied as
usual. Note that, as with the specular map, the glTF `specularFactor` is
twice Bevy's `reflectance` value.

This PR adds a new example, `specular_tint`, which demonstrates the
specular tint and map features. Note that this example requires the
[`KHR_materials_specular`] Cargo feature.

[`KHR_materials_specular`]:
https://github.com/KhronosGroup/glTF/tree/main/extensions/2.0/Khronos/KHR_materials_specular

## Changelog

### Added

* Specular highlights can now be tinted with the `specular_tint` field
in `StandardMaterial`.
* Specular maps are now available in `StandardMaterial`, gated behind
the `pbr_specular_textures` Cargo feature.
* The `KHR_materials_specular` glTF extension is now supported, allowing
for customization of specular reflectance and specular maps. Note that
the latter are gated behind the `pbr_specular_textures` Cargo feature.
2025-01-26 20:38:46 +00:00
Zachary Harrold
9bc0ae33c3
Move hashbrown and foldhash out of bevy_utils (#17460)
# Objective

- Contributes to #16877

## Solution

- Moved `hashbrown`, `foldhash`, and related types out of `bevy_utils`
and into `bevy_platform_support`
- Refactored the above to match the layout of these types in `std`.
- Updated crates as required.

## Testing

- CI

---

## Migration Guide

- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::hash`:
  - `FixedState`
  - `DefaultHasher`
  - `RandomState`
  - `FixedHasher`
  - `Hashed`
  - `PassHash`
  - `PassHasher`
  - `NoOpHash`
- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::collections`:
  - `HashMap`
  - `HashSet`
- `bevy_utils::hashbrown` has been removed. Instead, import from
`bevy_platform_support::collections` _or_ take a dependency on
`hashbrown` directly.
- `bevy_utils::Entry` has been removed. Instead, import from
`bevy_platform_support::collections::hash_map` or
`bevy_platform_support::collections::hash_set` as appropriate.
- All of the above equally apply to `bevy::utils` and
`bevy::platform_support`.

## Notes

- I left `PreHashMap`, `PreHashMapExt`, and `TypeIdMap` in `bevy_utils`
as they might be candidates for micro-crating. They can always be moved
into `bevy_platform_support` at a later date if desired.
2025-01-23 16:46:08 +00:00
Carter Anderson
21f1e3045c
Relationships (non-fragmenting, one-to-many) (#17398)
This adds support for one-to-many non-fragmenting relationships (with
planned paths for fragmenting and non-fragmenting many-to-many
relationships). "Non-fragmenting" means that entities with the same
relationship type, but different relationship targets, are not forced
into separate tables (which would cause "table fragmentation").

Functionally, this fills a similar niche as the current Parent/Children
system. The biggest differences are:

1. Relationships have simpler internals and significantly improved
performance and UX. Commands and specialized APIs are no longer
necessary to keep everything in sync. Just spawn entities with the
relationship components you want and everything "just works".
2. Relationships are generalized. Bevy can provide additional built in
relationships, and users can define their own.

**REQUEST TO REVIEWERS**: _please don't leave top level comments and
instead comment on specific lines of code. That way we can take
advantage of threaded discussions. Also dont leave comments simply
pointing out CI failures as I can read those just fine._

## Built on top of what we have

Relationships are implemented on top of the Bevy ECS features we already
have: components, immutability, and hooks. This makes them immediately
compatible with all of our existing (and future) APIs for querying,
spawning, removing, scenes, reflection, etc. The fewer specialized APIs
we need to build, maintain, and teach, the better.

## Why focus on one-to-many non-fragmenting first?

1. This allows us to improve Parent/Children relationships immediately,
in a way that is reasonably uncontroversial. Switching our hierarchy to
fragmenting relationships would have significant performance
implications. ~~Flecs is heavily considering a switch to non-fragmenting
relations after careful considerations of the performance tradeoffs.~~
_(Correction from @SanderMertens: Flecs is implementing non-fragmenting
storage specialized for asset hierarchies, where asset hierarchies are
many instances of small trees that have a well defined structure)_
2. Adding generalized one-to-many relationships is currently a priority
for the [Next Generation Scene / UI
effort](https://github.com/bevyengine/bevy/discussions/14437).
Specifically, we're interested in building reactions and observers on
top.

## The changes

This PR does the following:

1. Adds a generic one-to-many Relationship system
3. Ports the existing Parent/Children system to Relationships, which now
lives in `bevy_ecs::hierarchy`. The old `bevy_hierarchy` crate has been
removed.
4. Adds on_despawn component hooks
5. Relationships can opt-in to "despawn descendants" behavior, meaning
that the entire relationship hierarchy is despawned when
`entity.despawn()` is called. The built in Parent/Children hierarchies
enable this behavior, and `entity.despawn_recursive()` has been removed.
6. `world.spawn` now applies commands after spawning. This ensures that
relationship bookkeeping happens immediately and removes the need to
manually flush. This is in line with the equivalent behaviors recently
added to the other APIs (ex: insert).
7. Removes the ValidParentCheckPlugin (system-driven / poll based) in
favor of a `validate_parent_has_component` hook.

## Using Relationships

The `Relationship` trait looks like this:

```rust
pub trait Relationship: Component + Sized {
    type RelationshipSources: RelationshipSources<Relationship = Self>;
    fn get(&self) -> Entity;
    fn from(entity: Entity) -> Self;
}
```

A relationship is a component that:

1. Is a simple wrapper over a "target" Entity.
2. Has a corresponding `RelationshipSources` component, which is a
simple wrapper over a collection of entities. Every "target entity"
targeted by a "source entity" with a `Relationship` has a
`RelationshipSources` component, which contains every "source entity"
that targets it.

For example, the `Parent` component (as it currently exists in Bevy) is
the `Relationship` component and the entity containing the Parent is the
"source entity". The entity _inside_ the `Parent(Entity)` component is
the "target entity". And that target entity has a `Children` component
(which implements `RelationshipSources`).

In practice, the Parent/Children relationship looks like this:

```rust
#[derive(Relationship)]
#[relationship(relationship_sources = Children)]
pub struct Parent(pub Entity);

#[derive(RelationshipSources)]
#[relationship_sources(relationship = Parent)]
pub struct Children(Vec<Entity>);
```

The Relationship and RelationshipSources derives automatically implement
Component with the relevant configuration (namely, the hooks necessary
to keep everything in sync).

The most direct way to add relationships is to spawn entities with
relationship components:

```rust
let a = world.spawn_empty().id();
let b = world.spawn(Parent(a)).id();

assert_eq!(world.entity(a).get::<Children>().unwrap(), &[b]);
```

There are also convenience APIs for spawning more than one entity with
the same relationship:

```rust
world.spawn_empty().with_related::<Children>(|s| {
    s.spawn_empty();
    s.spawn_empty();
})
```

The existing `with_children` API is now a simpler wrapper over
`with_related`. This makes this change largely non-breaking for existing
spawn patterns.

```rust
world.spawn_empty().with_children(|s| {
    s.spawn_empty();
    s.spawn_empty();
})
```

There are also other relationship APIs, such as `add_related` and
`despawn_related`.

## Automatic recursive despawn via the new on_despawn hook

`RelationshipSources` can opt-in to "despawn descendants" behavior,
which will despawn all related entities in the relationship hierarchy:

```rust
#[derive(RelationshipSources)]
#[relationship_sources(relationship = Parent, despawn_descendants)]
pub struct Children(Vec<Entity>);
```

This means that `entity.despawn_recursive()` is no longer required.
Instead, just use `entity.despawn()` and the relevant related entities
will also be despawned.

To despawn an entity _without_ despawning its parent/child descendants,
you should remove the `Children` component first, which will also remove
the related `Parent` components:

```rust
entity
    .remove::<Children>()
    .despawn()
```

This builds on the on_despawn hook introduced in this PR, which is fired
when an entity is despawned (before other hooks).

## Relationships are the source of truth

`Relationship` is the _single_ source of truth component.
`RelationshipSources` is merely a reflection of what all the
`Relationship` components say. By embracing this, we are able to
significantly improve the performance of the system as a whole. We can
rely on component lifecycles to protect us against duplicates, rather
than needing to scan at runtime to ensure entities don't already exist
(which results in quadratic runtime). A single source of truth gives us
constant-time inserts. This does mean that we cannot directly spawn
populated `Children` components (or directly add or remove entities from
those components). I personally think this is a worthwhile tradeoff,
both because it makes the performance much better _and_ because it means
theres exactly one way to do things (which is a philosophy we try to
employ for Bevy APIs).

As an aside: treating both sides of the relationship as "equivalent
source of truth relations" does enable building simple and flexible
many-to-many relationships. But this introduces an _inherent_ need to
scan (or hash) to protect against duplicates.
[`evergreen_relations`](https://github.com/EvergreenNest/evergreen_relations)
has a very nice implementation of the "symmetrical many-to-many"
approach. Unfortunately I think the performance issues inherent to that
approach make it a poor choice for Bevy's default relationship system.

## Followup Work

* Discuss renaming `Parent` to `ChildOf`. I refrained from doing that in
this PR to keep the diff reasonable, but I'm personally biased toward
this change (and using that naming pattern generally for relationships).
* [Improved spawning
ergonomics](https://github.com/bevyengine/bevy/discussions/16920)
* Consider adding relationship observers/triggers for "relationship
targets" whenever a source is added or removed. This would replace the
current "hierarchy events" system, which is unused upstream but may have
existing users downstream. I think triggers are the better fit for this
than a buffered event queue, and would prefer not to add that back.
* Fragmenting relations: My current idea hinges on the introduction of
"value components" (aka: components whose type _and_ value determines
their ComponentId, via something like Hashing / PartialEq). By labeling
a Relationship component such as `ChildOf(Entity)` as a "value
component", `ChildOf(e1)` and `ChildOf(e2)` would be considered
"different components". This makes the transition between fragmenting
and non-fragmenting a single flag, and everything else continues to work
as expected.
* Many-to-many support
* Non-fragmenting: We can expand Relationship to be a list of entities
instead of a single entity. I have largely already written the code for
this.
* Fragmenting: With the "value component" impl mentioned above, we get
many-to-many support "for free", as it would allow inserting multiple
copies of a Relationship component with different target entities.

Fixes #3742 (If this PR is merged, I think we should open more targeted
followup issues for the work above, with a fresh tracking issue free of
the large amount of less-directed historical context)
Fixes #17301
Fixes #12235 
Fixes #15299
Fixes #15308 

## Migration Guide

* Replace `ChildBuilder` with `ChildSpawnerCommands`.
* Replace calls to `.set_parent(parent_id)` with
`.insert(Parent(parent_id))`.
* Replace calls to `.replace_children()` with `.remove::<Children>()`
followed by `.add_children()`. Note that you'll need to manually despawn
any children that are not carried over.
* Replace calls to `.despawn_recursive()` with `.despawn()`.
* Replace calls to `.despawn_descendants()` with
`.despawn_related::<Children>()`.
* If you have any calls to `.despawn()` which depend on the children
being preserved, you'll need to remove the `Children` component first.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-01-18 22:20:30 +00:00
github-actions[bot]
573b980685
Bump Version after Release (#17176)
Bump version after release
This PR has been auto-generated

---------

Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
2025-01-06 00:04:44 +00:00
Zachary Harrold
a371ee3019
Remove tracing re-export from bevy_utils (#17161)
# Objective

- Contributes to #11478

## Solution

- Made `bevy_utils::tracing` `doc(hidden)`
- Re-exported `tracing` from `bevy_log` for end-users
- Added `tracing` directly to crates that need it.

## Testing

- CI

---

## Migration Guide

If you were importing `tracing` via `bevy::utils::tracing`, instead use
`bevy::log::tracing`. Note that many items within `tracing` are also
directly re-exported from `bevy::log` as well, so you may only need
`bevy::log` for the most common items (e.g., `warn!`, `trace!`, etc.).
This also applies to the `log_once!` family of macros.

## Notes

- While this doesn't reduce the line-count in `bevy_utils`, it further
decouples the internal crates from `bevy_utils`, making its eventual
removal more feasible in the future.
- I have just imported `tracing` as we do for all dependencies. However,
a workspace dependency may be more appropriate for version management.
2025-01-05 23:06:34 +00:00
Zachary Harrold
21786632c3
Remove bevy_core (#16897)
# Objective

- Fixes #16892

## Solution

- Removed `TypeRegistryPlugin` (`Name` is now automatically registered
with a default `App`)
- Moved `TaskPoolPlugin` to `bevy_app`
- Moved `FrameCountPlugin` to `bevy_diagnostic`
- Deleted now-empty `bevy_core`

## Testing

- CI

## Migration Guide

- `TypeRegistryPlugin` no longer exists. If you can't use a default
`App` but still need `Name` registered, do so manually with
`app.register_type::<Name>()`.
- References to `TaskPoolPlugin` and associated types will need to
import it from `bevy_app` instead of `bevy_core`
- References to `FrameCountPlugin` and associated types will need to
import it from `bevy_diagnostic` instead of `bevy_core`

## Notes

This strategy was agreed upon by Cart and several other members in
[Discord](https://discord.com/channels/691052431525675048/692572690833473578/1319137218312278077).
2024-12-19 18:36:51 +00:00
Zachary Harrold
a6adced9ed
Deny derive_more error feature and replace it with thiserror (#16684)
# Objective

- Remove `derive_more`'s error derivation and replace it with
`thiserror`

## Solution

- Added `derive_more`'s `error` feature to `deny.toml` to prevent it
sneaking back in.
- Reverted to `thiserror` error derivation

## Notes

Merge conflicts were too numerous to revert the individual changes, so
this reversion was done manually. Please scrutinise carefully during
review.
2024-12-06 17:03:55 +00:00
Zachary Harrold
f88c6820f0
Remove thiserror from bevy_gltf (#15772)
# Objective

- Contributes to #15460

## Solution

- Removed `thiserror` from `bevy_gltf`
2024-10-09 14:22:00 +00:00
Clar Fon
8adc9e9d6e
Feature-gate all image formats (#15586)
# Objective

Bevy supports feature gates for each format it supports, but several
formats that it loads via the `image` crate do not have feature gates.
Additionally, the QOI format is supported by the `image` crate and
wasn't available at all. This fixes that.

## Solution

The following feature gates are added:

* `avif`
* `ff` (Farbfeld)
* `gif`
* `ico`
* `qoi`
* `tiff`

None of these formats are enabled by default, despite the fact that all
these formats appeared to be enabled by default before. Since
`default-features` was disabled for the `image` crate, it's likely that
using any of these formats would have errored by default before this
change, although this probably needs additional testing.

## Testing

The changes seemed minimal enough that a compile test would be
sufficient.

## Migration guide

Image formats that previously weren't feature-gated are now
feature-gated, meaning they will have to be enabled if you use them:

* `avif`
* `ff` (Farbfeld)
* `gif`
* `ico`
* `tiff`

Additionally, the `qoi` feature has been added to support loading QOI
format images.

Previously, these formats appeared in the enum by default, but weren't
actually enabled via the `image` crate, potentially resulting in weird
bugs. Now, you should be able to add these features to your projects to
support them properly.
2024-10-07 16:37:45 +00:00
Giacomo Stevanato
71c5f1e3e4
Generate links to definition in source code pages on docs.rs and dev-docs.bevyengine.org (#12965)
# Objective

- Fix issue #2611

## Solution

- Add `--generate-link-to-definition` to all the `rustdoc-args` arrays
in the `Cargo.toml`s (for docs.rs)
- Add `--generate-link-to-definition` to the `RUSTDOCFLAGS` environment
variable in the docs workflow (for dev-docs.bevyengine.org)
- Document all the workspace crates in the docs workflow (needed because
otherwise only the source code of the `bevy` package will be included,
making the argument useless)
- I think this also fixes #3662, since it fixes the bug on
dev-docs.bevyengine.org, while on docs.rs it has been fixed for a while
on their side.

---

## Changelog

- The source code viewer on docs.rs now includes links to the
definitions.
2024-07-29 23:10:16 +00:00
BD103
ee4ed231da
Fix bevy_gltf PBR features not enabling corresponding bevy_pbr flags (#14486)
# Objective

- `bevy_gltf` does not build with only the
`pbr_multi_layer_material_textures` or `pbr_anisotropy_texture`
features.
- Caught by [`flag-frenzy`](https://github.com/TheBevyFlock/flag-frenzy)
in [this
run](https://github.com/TheBevyFlock/flag-frenzy/actions/runs/10087486444/job/27891723948).

## Solution

- This error was due to the feature not enabling the corresponding
feature in `bevy_pbr`. Adding these flags as a dependency fixes this
error.

## Testing

The following commands fail on `main`, but pass with this PR:

```bash
cargo check -p bevy_gltf --no-default-features -F pbr_multi_layer_material_textures
cargo check -p bevy_gltf --no-default-features -F pbr_anisotropy_texture
```
2024-07-26 17:11:38 +00:00
Coder-Joe458
8f5345573c
Remove manual --cfg docsrs (#14376)
# Objective

- Fixes #14132 

## Solution

- Remove the cfg docsrs
2024-07-22 18:58:04 +00:00
François Mockers
c0b35d07f3
fix building cargo_gltf with feature dds (#14360)
# Objective

- Building bevy_gltf with feature dds fails:
```
> cargo build -p bevy_gltf --features dds
   Compiling bevy_core_pipeline v0.15.0-dev (crates/bevy_core_pipeline)
error[E0061]: this function takes 7 arguments but 6 arguments were supplied
   --> crates/bevy_core_pipeline/src/tonemapping/mod.rs:442:5
    |
442 |     Image::from_buffer(
    |     ^^^^^^^^^^^^^^^^^^
...
445 |         bytes,
    |         ----- an argument of type `std::string::String` is missing
    |
note: associated function defined here
   --> crates/bevy_render/src/texture/image.rs:709:12
    |
709 |     pub fn from_buffer(
    |            ^^^^^^^^^^^
help: provide the argument
    |
442 |     Image::from_buffer(/* std::string::String */, bytes, image_type, CompressedImageFormats::NONE, false, image_sampler, RenderAssetUsages::RENDER_WORLD)
    |                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For more information about this error, try `rustc --explain E0061`.
error: could not compile `bevy_core_pipeline` (lib) due to 1 previous error
```
- If you're fixing a specific issue, say "Fixes #X".

## Solution

- enable dds feature in bevy_core_pipeline

## Testing

- `cargo build -p bevy_gltf --features dds`
2024-07-20 17:55:25 +00:00
github-actions[bot]
8df10d2713
Bump Version after Release (#14219)
Bump version after release
This PR has been auto-generated

Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
2024-07-08 12:54:08 +00:00
Gagnus
a47b91cccc
Added feature switch to default Standard Material's new anisotropy texture to off (#14048)
# Objective

- Standard Material is starting to run out of samplers (currently uses
13 with no additional features off, I think in 0.13 it was 12).
- This change adds a new feature switch, modelled on the other ones
which add features to Standard Material, to turn off the new anisotropy
feature by default.

## Solution

- feature + texture define

## Testing

- Anisotropy example still works fine
- Other samples work fine
- Standard Material now takes 12 samplers by default on my Mac instead
of 13

## Migration Guide

- Add feature pbr_anisotropy_texture if you are using that texture in
any standard materials.

---------

Co-authored-by: John Payne <20407779+johngpayne@users.noreply.github.com>
2024-07-02 18:02:05 +00:00
Mikhail Novikov
cb4fe4ea9e
Make gLTF node children Handle instead of objects (#13707)
Part of #13681 

# Objective

gLTF Assets shouldn't be duplicated between Assets resource and node
children.

Also changed `asset_label` to be a method as [per previous PR
comment](https://github.com/bevyengine/bevy/pull/13558).

## Solution

- Made GltfNode children be Handles instead of asset copies.

## Testing

- Added tests that actually test loading and hierarchy as previous ones
unit tested only one function and that makes little sense.
- Made circular nodes an actual loading failure instead of a warning
no-op. You [_MUST NOT_ have cycles in
gLTF](https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#nodes-and-hierarchy)
according to the spec.
- IMO this is a bugfix, not a breaking change. But in an extremely
unlikely event in which you relied on invalid behavior for loading gLTF
with cyclic children, you will not be able to do that anymore. You
should fix your gLTF file as it's not valid according to gLTF spec. For
it to for work someone, it had to be bevy with bevy_animation flag off.

---

## Changelog

### Changed

- `GltfNode.children` are now `Vec<Handle<GltfNode>>` instead of
`Vec<GltfNode>`
- Having children cycles between gLTF nodes in a gLTF document is now an
explicit asset loading failure.

## Migration Guide

If accessing children, use `Assets<GltfNode>` resource to get the actual
child object.

#### Before

```rs
fn gltf_print_first_node_children_system(gltf_component_query: Query<Handle<Gltf>>, gltf_assets: Res<Assets<Gltf>>, gltf_nodes: Res<Assets<GltfNode>>) {
    for gltf_handle in gltf_component_query.iter() {
        let gltf_root = gltf_assets.get(gltf_handle).unwrap();
        let first_node_handle = gltf_root.nodes.get(0).unwrap();
        let first_node = gltf_nodes.get(first_node_handle).unwrap();
        let first_child = first_node.children.get(0).unwrap();
        println!("First nodes child node name is {:?)", first_child.name);
    }
}
```

#### After

```rs
fn gltf_print_first_node_children_system(gltf_component_query: Query<Handle<Gltf>>, gltf_assets: Res<Assets<Gltf>>, gltf_nodes: Res<Assets<GltfNode>>) {
    for gltf_handle in gltf_component_query.iter() {
        let gltf_root = gltf_assets.get(gltf_handle).unwrap();
        let first_node_handle = gltf_root.nodes.get(0).unwrap();
        let first_node = gltf_nodes.get(first_node_handle).unwrap();
        let first_child_handle = first_node.children.get(0).unwrap();
        let first_child = gltf_nodes.get(first_child_handle).unwrap();
        println!("First nodes child node name is {:?)", first_child.name);
    }
}
```
2024-07-01 14:05:16 +00:00
Patrick Walton
77ed72bc16
Implement clearcoat per the Filament and the KHR_materials_clearcoat specifications. (#13031)
Clearcoat is a separate material layer that represents a thin
translucent layer of a material. Examples include (from the [Filament
spec]) car paint, soda cans, and lacquered wood. This commit implements
support for clearcoat following the Filament and Khronos specifications,
marking the beginnings of support for multiple PBR layers in Bevy.

The [`KHR_materials_clearcoat`] specification describes the clearcoat
support in glTF. In Blender, applying a clearcoat to the Principled BSDF
node causes the clearcoat settings to be exported via this extension. As
of this commit, Bevy parses and reads the extension data when present in
glTF. Note that the `gltf` crate has no support for
`KHR_materials_clearcoat`; this patch therefore implements the JSON
semantics manually.

Clearcoat is integrated with `StandardMaterial`, but the code is behind
a series of `#ifdef`s that only activate when clearcoat is present.
Additionally, the `pbr_feature_layer_material_textures` Cargo feature
must be active in order to enable support for clearcoat factor maps,
clearcoat roughness maps, and clearcoat normal maps. This approach
mirrors the same pattern used by the existing transmission feature and
exists to avoid running out of texture bindings on platforms like WebGL
and WebGPU. Note that constant clearcoat factors and roughness values
*are* supported in the browser; only the relatively-less-common maps are
disabled on those platforms.

This patch refactors the lighting code in `StandardMaterial`
significantly in order to better support multiple layers in a natural
way. That code was due for a refactor in any case, so this is a nice
improvement.

A new demo, `clearcoat`, has been added. It's based on [the
corresponding three.js demo], but all the assets (aside from the skybox
and environment map) are my original work.

[Filament spec]:
https://google.github.io/filament/Filament.html#materialsystem/clearcoatmodel

[`KHR_materials_clearcoat`]:
https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Khronos/KHR_materials_clearcoat/README.md

[the corresponding three.js demo]:
https://threejs.org/examples/webgl_materials_physical_clearcoat.html

![Screenshot 2024-04-19
101143](https://github.com/bevyengine/bevy/assets/157897/3444bcb5-5c20-490c-b0ad-53759bd47ae2)

![Screenshot 2024-04-19
102054](https://github.com/bevyengine/bevy/assets/157897/6e953944-75b8-49ef-bc71-97b0a53b3a27)

## Changelog

### Added

* `StandardMaterial` now supports a clearcoat layer, which represents a
thin translucent layer over an underlying material.
* The glTF loader now supports the `KHR_materials_clearcoat` extension,
representing materials with clearcoat layers.

## Migration Guide

* The lighting functions in the `pbr_lighting` WGSL module now have
clearcoat parameters, if `STANDARD_MATERIAL_CLEARCOAT` is defined.

* The `R` reflection vector parameter has been removed from some
lighting functions, as it was unused.
2024-05-05 22:57:05 +00:00
Ycy
9d8f94d461
fix bevy_gltf crate build (#13202)
# Objective

Fixing `bevy_gltf` crate build fail when `bevy_animation` feature is
disabled

## Solution

Add missing `bevy_animation` feature
2024-05-03 13:00:18 +00:00
Ame
72c51cdab9
Make feature(doc_auto_cfg) work (#12642)
# Objective

- In #12366 `![cfg_attr(docsrs, feature(doc_auto_cfg))] `was added. But
to apply it it needs `--cfg=docsrs` in rustdoc-args.


## Solution

- Apply `--cfg=docsrs` to all crates and CI.

I also added `[package.metadata.docs.rs]` to all crates to avoid adding
code behind a feature and forget adding the metadata.

Before:

![Screenshot 2024-03-22 at 00 51
57](https://github.com/bevyengine/bevy/assets/104745335/6a9dfdaa-8710-4784-852b-5f9b74e3522c)

After:
![Screenshot 2024-03-22 at 00 51
32](https://github.com/bevyengine/bevy/assets/104745335/c5bd6d8e-8ddb-45b3-b844-5ecf9f88961c)
2024-03-23 02:22:52 +00:00
dependabot[bot]
5cf7d9213e
Update base64 requirement from 0.21.5 to 0.22.0 (#12552)
Updates the requirements on
[base64](https://github.com/marshallpierce/rust-base64) to permit the
latest version.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/marshallpierce/rust-base64/blob/master/RELEASE-NOTES.md">base64's
changelog</a>.</em></p>
<blockquote>
<h1>0.22.0</h1>
<ul>
<li><code>DecodeSliceError::OutputSliceTooSmall</code> is now
conservative rather than precise. That is, the error will only occur if
the decoded output <em>cannot</em> fit, meaning that
<code>Engine::decode_slice</code> can now be used with exactly-sized
output slices. As part of this, <code>Engine::internal_decode</code> now
returns <code>DecodeSliceError</code> instead of
<code>DecodeError</code>, but that is not expected to affect any
external callers.</li>
<li><code>DecodeError::InvalidLength</code> now refers specifically to
the <em>number of valid symbols</em> being invalid (i.e. <code>len % 4
== 1</code>), rather than just the number of input bytes. This avoids
confusing scenarios when based on interpretation you could make a case
for either <code>InvalidLength</code> or <code>InvalidByte</code> being
appropriate.</li>
<li>Decoding is somewhat faster (5-10%)</li>
</ul>
<h1>0.21.7</h1>
<ul>
<li>Support getting an alphabet's contents as a str via
<code>Alphabet::as_str()</code></li>
</ul>
<h1>0.21.6</h1>
<ul>
<li>Improved introductory documentation and example</li>
</ul>
<h1>0.21.5</h1>
<ul>
<li>Add <code>Debug</code> and <code>Clone</code> impls for the general
purpose Engine</li>
</ul>
<h1>0.21.4</h1>
<ul>
<li>Make <code>encoded_len</code> <code>const</code>, allowing the
creation of arrays sized to encode compile-time-known data lengths</li>
</ul>
<h1>0.21.3</h1>
<ul>
<li>Implement <code>source</code> instead of <code>cause</code> on Error
types</li>
<li>Roll back MSRV to 1.48.0 so Debian can continue to live in a time
warp</li>
<li>Slightly faster chunked encoding for short inputs</li>
<li>Decrease binary size</li>
</ul>
<h1>0.21.2</h1>
<ul>
<li>Rollback MSRV to 1.57.0 -- only dev dependencies need 1.60, not the
main code</li>
</ul>
<h1>0.21.1</h1>
<ul>
<li>Remove the possibility of panicking during decoded length
calculations</li>
<li><code>DecoderReader</code> no longer sometimes erroneously ignores
padding <a
href="https://redirect.github.com/marshallpierce/rust-base64/issues/226">#226</a></li>
</ul>
<h2>Breaking changes</h2>
<ul>
<li><code>Engine.internal_decode</code> return type changed</li>
<li>Update MSRV to 1.60.0</li>
</ul>
<h1>0.21.0</h1>
<h2>Migration</h2>
<h3>Functions</h3>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="5d70ba7576"><code>5d70ba7</code></a>
Merge pull request <a
href="https://redirect.github.com/marshallpierce/rust-base64/issues/269">#269</a>
from marshallpierce/mp/decode-precisely</li>
<li><a
href="efb6c006c7"><code>efb6c00</code></a>
Release notes</li>
<li><a
href="2b91084a31"><code>2b91084</code></a>
Add some tests to boost coverage</li>
<li><a
href="9e9c7abe65"><code>9e9c7ab</code></a>
Engine::internal_decode now returns DecodeSliceError</li>
<li><a
href="a8a60f43c5"><code>a8a60f4</code></a>
Decode main loop improvements</li>
<li><a
href="a25be0667c"><code>a25be06</code></a>
Simplify leftover output writes</li>
<li><a
href="9979cc33bb"><code>9979cc3</code></a>
Keep morsels as separate bytes</li>
<li><a
href="37670c5ec2"><code>37670c5</code></a>
Bump dev toolchain version (<a
href="https://redirect.github.com/marshallpierce/rust-base64/issues/268">#268</a>)</li>
<li><a
href="9652c78773"><code>9652c78</code></a>
v0.21.7</li>
<li><a
href="08deccf703"><code>08deccf</code></a>
provide as_str() method to return the alphabet characters (<a
href="https://redirect.github.com/marshallpierce/rust-base64/issues/264">#264</a>)</li>
<li>Additional commits viewable in <a
href="https://github.com/marshallpierce/rust-base64/compare/v0.21.5...v0.22.0">compare
view</a></li>
</ul>
</details>
<br />


Dependabot will resolve any conflicts with this PR as long as you don't
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2024-03-18 06:42:58 +00:00
Al M
52e3f2007b
Add "all-features = true" to docs.rs metadata for most crates (#12366)
# Objective

Fix missing `TextBundle` (and many others) which are present in the main
crate as default features but optional in the sub-crate. See:

- https://docs.rs/bevy/0.13.0/bevy/ui/node_bundles/index.html
- https://docs.rs/bevy_ui/0.13.0/bevy_ui/node_bundles/index.html

~~There are probably other instances in other crates that I could track
down, but maybe "all-features = true" should be used by default in all
sub-crates? Not sure.~~ (There were many.) I only noticed this because
rust-analyzer's "open docs" features takes me to the sub-crate, not the
main one.

## Solution

Add "all-features = true" to docs.rs metadata for crates that use
features.

## Changelog

### Changed

- Unified features documented on docs.rs between main crate and
sub-crates
2024-03-08 20:03:09 +00:00
James Liu
512b7463a3
Disentangle bevy_utils/bevy_core's reexported dependencies (#12313)
# Objective
Make bevy_utils less of a compilation bottleneck. Tackle #11478.

## Solution
* Move all of the directly reexported dependencies and move them to
where they're actually used.
* Remove the UUID utilities that have gone unused since `TypePath` took
over for `TypeUuid`.
* There was also a extraneous bytemuck dependency on `bevy_core` that
has not been used for a long time (since `encase` became the primary way
to prepare GPU buffers).
* Remove the `all_tuples` macro reexport from bevy_ecs since it's
accessible from `bevy_utils`.

---

## Changelog
Removed: Many of the reexports from bevy_utils (petgraph, uuid, nonmax,
smallvec, and thiserror).
Removed: bevy_core's reexports of bytemuck.

## Migration Guide
bevy_utils' reexports of petgraph, uuid, nonmax, smallvec, and thiserror
have been removed.

bevy_core' reexports of bytemuck's types has been removed. 

Add them as dependencies in your own crate instead.
2024-03-07 02:30:15 +00:00
James Liu
5619bd09d1
Replace bevy_log's tracing reexport with bevy_utils' (#12254)
# Objective
Fixes #11298. Make the use of bevy_log vs bevy_utils::tracing more
consistent.

## Solution
Replace all uses of bevy_log's logging macros with the reexport from
bevy_utils. Remove bevy_log as a dependency where it's no longer needed
anymore.

Ideally we should just be using tracing directly, but given that all of
these crates are already using bevy_utils, this likely isn't that great
of a loss right now.
2024-03-02 18:38:04 +00:00
Alice Cecile
599e5e4e76
Migrate from LegacyColor to bevy_color::Color (#12163)
# Objective

- As part of the migration process we need to a) see the end effect of
the migration on user ergonomics b) check for serious perf regressions
c) actually migrate the code
- To accomplish this, I'm going to attempt to migrate all of the
remaining user-facing usages of `LegacyColor` in one PR, being careful
to keep a clean commit history.
- Fixes #12056.

## Solution

I've chosen to use the polymorphic `Color` type as our standard
user-facing API.

- [x] Migrate `bevy_gizmos`.
- [x] Take `impl Into<Color>` in all `bevy_gizmos` APIs
- [x] Migrate sprites
- [x] Migrate UI
- [x] Migrate `ColorMaterial`
- [x] Migrate `MaterialMesh2D`
- [x] Migrate fog
- [x] Migrate lights
- [x] Migrate StandardMaterial
- [x] Migrate wireframes
- [x] Migrate clear color
- [x] Migrate text
- [x] Migrate gltf loader
- [x] Register color types for reflection
- [x] Remove `LegacyColor`
- [x] Make sure CI passes

Incidental improvements to ease migration:

- added `Color::srgba_u8`, `Color::srgba_from_array` and friends
- added `set_alpha`, `is_fully_transparent` and `is_fully_opaque` to the
`Alpha` trait
- add and immediately deprecate (lol) `Color::rgb` and friends in favor
of more explicit and consistent `Color::srgb`
- standardized on white and black for most example text colors
- added vector field traits to `LinearRgba`: ~~`Add`, `Sub`,
`AddAssign`, `SubAssign`,~~ `Mul<f32>` and `Div<f32>`. Multiplications
and divisions do not scale alpha. `Add` and `Sub` have been cut from
this PR.
- added `LinearRgba` and `Srgba` `RED/GREEN/BLUE`
- added `LinearRgba_to_f32_array` and `LinearRgba::to_u32`

## Migration Guide

Bevy's color types have changed! Wherever you used a
`bevy::render::Color`, a `bevy::color::Color` is used instead.

These are quite similar! Both are enums storing a color in a specific
color space (or to be more precise, using a specific color model).
However, each of the different color models now has its own type.

TODO...

- `Color::rgba`, `Color::rgb`, `Color::rbga_u8`, `Color::rgb_u8`,
`Color::rgb_from_array` are now `Color::srgba`, `Color::srgb`,
`Color::srgba_u8`, `Color::srgb_u8` and `Color::srgb_from_array`.
- `Color::set_a` and `Color::a` is now `Color::set_alpha` and
`Color::alpha`. These are part of the `Alpha` trait in `bevy_color`.
- `Color::is_fully_transparent` is now part of the `Alpha` trait in
`bevy_color`
- `Color::r`, `Color::set_r`, `Color::with_r` and the equivalents for
`g`, `b` `h`, `s` and `l` have been removed due to causing silent
relatively expensive conversions. Convert your `Color` into the desired
color space, perform your operations there, and then convert it back
into a polymorphic `Color` enum.
- `Color::hex` is now `Srgba::hex`. Call `.into` or construct a
`Color::Srgba` variant manually to convert it.
- `WireframeMaterial`, `ExtractedUiNode`, `ExtractedDirectionalLight`,
`ExtractedPointLight`, `ExtractedSpotLight` and `ExtractedSprite` now
store a `LinearRgba`, rather than a polymorphic `Color`
- `Color::rgb_linear` and `Color::rgba_linear` are now
`Color::linear_rgb` and `Color::linear_rgba`
- The various CSS color constants are no longer stored directly on
`Color`. Instead, they're defined in the `Srgba` color space, and
accessed via `bevy::color::palettes::css`. Call `.into()` on them to
convert them into a `Color` for quick debugging use, and consider using
the much prettier `tailwind` palette for prototyping.
- The `LIME_GREEN` color has been renamed to `LIMEGREEN` to comply with
the standard naming.
- Vector field arithmetic operations on `Color` (add, subtract, multiply
and divide by a f32) have been removed. Instead, convert your colors
into `LinearRgba` space, and perform your operations explicitly there.
This is particularly relevant when working with emissive or HDR colors,
whose color channel values are routinely outside of the ordinary 0 to 1
range.
- `Color::as_linear_rgba_f32` has been removed. Call
`LinearRgba::to_f32_array` instead, converting if needed.
- `Color::as_linear_rgba_u32` has been removed. Call
`LinearRgba::to_u32` instead, converting if needed.
- Several other color conversion methods to transform LCH or HSL colors
into float arrays or `Vec` types have been removed. Please reimplement
these externally or open a PR to re-add them if you found them
particularly useful.
- Various methods on `Color` such as `rgb` or `hsl` to convert the color
into a specific color space have been removed. Convert into
`LinearRgba`, then to the color space of your choice.
- Various implicitly-converting color value methods on `Color` such as
`r`, `g`, `b` or `h` have been removed. Please convert it into the color
space of your choice, then check these properties.
- `Color` no longer implements `AsBindGroup`. Store a `LinearRgba`
internally instead to avoid conversion costs.

---------

Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
Co-authored-by: Afonso Lage <lage.afonso@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
2024-02-29 19:35:12 +00:00
github-actions[bot]
e7c3359c4b
Bump Version after Release (#12020)
Fixes #12016.

Bump version after release
This PR has been auto-generated

Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François <mockersf@gmail.com>
2024-02-21 20:58:59 +00:00
Jan Hohenheim
8531033b31
Add support for KHR_texture_transform (#11904)
Adopted #8266, so copy-pasting the description from there:

# Objective

Support the KHR_texture_transform extension for the glTF loader.

- Fixes #6335
- Fixes #11869 
- Implements part of #11350
- Implements the GLTF part of #399 

## Solution

As is, this only supports a single transform. Looking at Godot's source,
they support one transform with an optional second one for detail, AO,
and emission. glTF specifies one per texture. The public domain
materials I looked at seem to share the same transform. So maybe having
just one is acceptable for now. I tried to include a warning if multiple
different transforms exist for the same material.

Note the gltf crate doesn't expose the texture transform for the normal
and occlusion textures, which it should, so I just ignored those for
now. (note by @janhohenheim: this is still the case)

Via `cargo run --release --example scene_viewer
~/src/clone/glTF-Sample-Models/2.0/TextureTransformTest/glTF/TextureTransformTest.gltf`:


![texture_transform](https://user-images.githubusercontent.com/283864/228938298-aa2ef524-555b-411d-9637-fd0dac226fb0.png)

## Changelog

Support for the
[KHR_texture_transform](https://github.com/KhronosGroup/glTF/tree/main/extensions/2.0/Khronos/KHR_texture_transform)
extension added. Texture UVs that were scaled, rotated, or offset in a
GLTF are now properly handled.

---------

Co-authored-by: Al McElrath <hello@yrns.org>
Co-authored-by: Kanabenki <lucien.menassol@gmail.com>
2024-02-21 01:11:28 +00:00
Carter Anderson
abb8c353f4
Release 0.13.0 (#11920)
Bump Bevy crates to 0.13.0 in preparation for release.

(Note that we accidentally skipped the `0.13.0-dev` step this cycle)
2024-02-17 09:24:25 +00:00
anarelion
94ab84e915
mipmap levels can be 0 and they should be interpreted as 1 (#11767)
# Objective

Loading some textures from the days of yonder give me errors cause the
mipmap level is 0

## Solution

Set a minimum of 1

## Changelog

Make mipmap level at least 1
2024-02-11 22:00:07 +00:00
Cornelius
a7b99f0500
GLTF extension support (#11138)
# Objective
Adds support for accessing raw extension data of loaded GLTF assets

## Solution
Via the GLTF loader settings, you can specify whether or not to include
the GLTF source. While not the ideal way of solving this problem,
modeling all of GLTF within Bevy just for extensions adds a lot of
complexity to the way Bevy handles GLTF currently. See the example GLTF
meta file and code
```
(
    meta_format_version: "1.0",
    asset: Load(
        loader: "bevy_gltf::loader::GltfLoader",
        settings: (
            load_meshes: true,
            load_cameras: true,
            load_lights: true,
            include_source: true,
        ),
    ),
)
```
```rs
pub fn load_gltf(mut commands: Commands, assets: Res<AssetServer>) {
    let my_gltf = assets.load("test_platform.gltf");

    commands.insert_resource(MyAssetPack {
        spawned: false,
        handle: my_gltf,
    });
}

#[derive(Resource)]
pub struct MyAssetPack {
    pub spawned: bool,
    pub handle: Handle<Gltf>,
}

pub fn spawn_gltf_objects(
    mut commands: Commands,
    mut my: ResMut<MyAssetPack>,
    assets_gltf: Res<Assets<Gltf>>,
) {
    // This flag is used to because this system has to be run until the asset is loaded.
    // If there's a better way of going about this I am unaware of it.
    if my.spawned {
        return;
    }

    if let Some(gltf) = assets_gltf.get(&my.handle) {
        info!("spawn");
        my.spawned = true;
        // spawn the first scene in the file
        commands.spawn(SceneBundle {
            scene: gltf.scenes[0].clone(),
            ..Default::default()
        });

        let source = gltf.source.as_ref().unwrap();
        info!("materials count {}", &source.materials().size_hint().0);
        info!(
            "materials ext is some {}",
            &source.materials().next().unwrap().extensions().is_some()
        );
    }
}
```

---

## Changelog
Added support for GLTF extensions through including raw GLTF source via
loader flag `GltfLoaderSettings::include_source == true`, stored in
`Gltf::source: Option<gltf::Gltf>`

## Migration Guide
This will have issues with "asset migrations", as there is currently no
way for .meta files to be migrated. Attempting to migrate .meta files
without the new flag will yield the following error:
```
bevy_asset::server: Failed to deserialize meta for asset test_platform.gltf: Failed to deserialize asset meta: SpannedError { code: MissingStructField { field: "include_source", outer: Some("GltfLoaderSettings") }, position: Position { line: 9, col: 9 } }
```
This means users who want to migrate their .meta files will have to add
the `include_source: true,` setting to their meta files by hand.
2024-01-15 15:38:01 +00:00
Martín Maita
3b59dbd772
Update base64 requirement from 0.13.0 to 0.21.5 (#10336)
# Objective

- Update base64 requirement from 0.13.0 to 0.21.5.
- Closes #10317.

## Solution

- Bumped `base64` requirement and manually migrated code to fix a
breaking change after updating.
2023-12-21 00:55:54 +00:00
Ame
8c0ce5280b
Standardize toml format with taplo (#10594)
# Objective

- Standardize fmt for toml files

## Solution

- Add [taplo](https://taplo.tamasfe.dev/) to CI (check for fmt and diff
for toml files), for context taplo is used by the most popular extension
in VScode [Even Better
TOML](https://marketplace.visualstudio.com/items?itemName=tamasfe.even-better-toml
- Add contribution section to explain toml fmt with taplo.
 
Now to pass CI you need to run `taplo fmt --option indent_string=" "` or
if you use vscode have the `Even Better TOML` extension with 4 spaces
for indent

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2023-11-21 01:04:14 +00:00
Ame
951c9bb1a2
Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011)
# Objective

- Fix adding `#![allow(clippy::type_complexity)]` everywhere. like #9796

## Solution

- Use the new [lints] table that will land in 1.74
(https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#lints)
- inherit lint to the workspace, crates and examples.
```
[lints]
workspace = true
```

## Changelog

- Bump rust version to 1.74
- Enable lints table for the workspace
```toml
[workspace.lints.clippy]
type_complexity = "allow"
```
- Allow type complexity for all crates and examples
```toml
[lints]
workspace = true
```

---------

Co-authored-by: Martín Maita <47983254+mnmaita@users.noreply.github.com>
2023-11-18 20:58:48 +00:00
github-actions[bot]
bf30a25efc
Release 0.12 (#10362)
Preparing next release
This PR has been auto-generated

---------

Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François <mockersf@gmail.com>
2023-11-04 17:24:23 +00:00
Marco Buono
44928e0df4
StandardMaterial Light Transmission (#8015)
# Objective

<img width="1920" alt="Screenshot 2023-04-26 at 01 07 34"
src="https://user-images.githubusercontent.com/418473/234467578-0f34187b-5863-4ea1-88e9-7a6bb8ce8da3.png">

This PR adds both diffuse and specular light transmission capabilities
to the `StandardMaterial`, with support for screen space refractions.
This enables realistically representing a wide range of real-world
materials, such as:

  - Glass; (Including frosted glass)
  - Transparent and translucent plastics;
  - Various liquids and gels;
  - Gemstones;
  - Marble;
  - Wax;
  - Paper;
  - Leaves;
  - Porcelain.

Unlike existing support for transparency, light transmission does not
rely on fixed function alpha blending, and therefore works with both
`AlphaMode::Opaque` and `AlphaMode::Mask` materials.

## Solution

- Introduces a number of transmission related fields in the
`StandardMaterial`;
- For specular transmission:
- Adds logic to take a view main texture snapshot after the opaque
phase; (in order to perform screen space refractions)
- Introduces a new `Transmissive3d` phase to the renderer, to which all
meshes with `transmission > 0.0` materials are sent.
- Calculates a light exit point (of the approximate mesh volume) using
`ior` and `thickness` properties
- Samples the snapshot texture with an adaptive number of taps across a
`roughness`-controlled radius enabling “blurry” refractions
- For diffuse transmission:
- Approximates transmitted diffuse light by using a second, flipped +
displaced, diffuse-only Lambertian lobe for each light source.

## To Do

- [x] Figure out where `fresnel_mix()` is taking place, if at all, and
where `dielectric_specular` is being calculated, if at all, and update
them to use the `ior` value (Not a blocker, just a nice-to-have for more
correct BSDF)
- To the _best of my knowledge, this is now taking place, after
964340cdd. The fresnel mix is actually "split" into two parts in our
implementation, one `(1 - fresnel(...))` in the transmission, and
`fresnel()` in the light implementations. A surface with more
reflectance now will produce slightly dimmer transmission towards the
grazing angle, as more of the light gets reflected.
- [x] Add `transmission_texture`
- [x] Add `diffuse_transmission_texture`
- [x] Add `thickness_texture`
- [x] Add `attenuation_distance` and `attenuation_color`
- [x] Connect values to glTF loader
  - [x] `transmission` and `transmission_texture`
  - [x] `thickness` and `thickness_texture`
  - [x] `ior`
- [ ] `diffuse_transmission` and `diffuse_transmission_texture` (needs
upstream support in `gltf` crate, not a blocker)
- [x] Add support for multiple screen space refraction “steps”
- [x] Conditionally create no transmission snapshot texture at all if
`steps == 0`
- [x] Conditionally enable/disable screen space refraction transmission
snapshots
- [x] Read from depth pre-pass to prevent refracting pixels in front of
the light exit point
- [x] Use `interleaved_gradient_noise()` function for sampling blur in a
way that benefits from TAA
- [x] Drill down a TAA `#define`, tweak some aspects of the effect
conditionally based on it
- [x] Remove const array that's crashing under HLSL (unless a new `naga`
release with https://github.com/gfx-rs/naga/pull/2496 comes out before
we merge this)
- [ ] Look into alternatives to the `switch` hack for dynamically
indexing the const array (might not be needed, compilers seem to be
decent at expanding it)
- [ ] Add pipeline keys for gating transmission (do we really want/need
this?)
- [x] Tweak some material field/function names?

## A Note on Texture Packing

_This was originally added as a comment to the
`specular_transmission_texture`, `thickness_texture` and
`diffuse_transmission_texture` documentation, I removed it since it was
more confusing than helpful, and will likely be made redundant/will need
to be updated once we have a better infrastructure for preprocessing
assets_

Due to how channels are mapped, you can more efficiently use a single
shared texture image
for configuring the following:

- R - `specular_transmission_texture`
- G - `thickness_texture`
- B - _unused_
- A - `diffuse_transmission_texture`

The `KHR_materials_diffuse_transmission` glTF extension also defines a
`diffuseTransmissionColorTexture`,
that _we don't currently support_. One might choose to pack the
intensity and color textures together,
using RGB for the color and A for the intensity, in which case this
packing advice doesn't really apply.

---

## Changelog

- Added a new `Transmissive3d` render phase for rendering specular
transmissive materials with screen space refractions
- Added rendering support for transmitted environment map light on the
`StandardMaterial` as a fallback for screen space refractions
- Added `diffuse_transmission`, `specular_transmission`, `thickness`,
`ior`, `attenuation_distance` and `attenuation_color` to the
`StandardMaterial`
- Added `diffuse_transmission_texture`, `specular_transmission_texture`,
`thickness_texture` to the `StandardMaterial`, gated behind a new
`pbr_transmission_textures` cargo feature (off by default, for maximum
hardware compatibility)
- Added `Camera3d::screen_space_specular_transmission_steps` for
controlling the number of “layers of transparency” rendered for
transmissive objects
- Added a `TransmittedShadowReceiver` component for enabling shadows in
(diffusely) transmitted light. (disabled by default, as it requires
carefully setting up the `thickness` to avoid self-shadow artifacts)
- Added support for the `KHR_materials_transmission`,
`KHR_materials_ior` and `KHR_materials_volume` glTF extensions
- Renamed items related to temporal jitter for greater consistency

## Migration Guide

- `SsaoPipelineKey::temporal_noise` has been renamed to
`SsaoPipelineKey::temporal_jitter`
- The `TAA` shader def (controlled by the presence of the
`TemporalAntiAliasSettings` component in the camera) has been replaced
with the `TEMPORAL_JITTER` shader def (controlled by the presence of the
`TemporalJitter` component in the camera)
- `MeshPipelineKey::TAA` has been replaced by
`MeshPipelineKey::TEMPORAL_JITTER`
- The `TEMPORAL_NOISE` shader def has been consolidated with
`TEMPORAL_JITTER`
2023-10-31 20:59:02 +00:00
Carter Anderson
5eb292dc10
Bevy Asset V2 (#8624)
# Bevy Asset V2 Proposal

## Why Does Bevy Need A New Asset System?

Asset pipelines are a central part of the gamedev process. Bevy's
current asset system is missing a number of features that make it
non-viable for many classes of gamedev. After plenty of discussions and
[a long community feedback
period](https://github.com/bevyengine/bevy/discussions/3972), we've
identified a number missing features:

* **Asset Preprocessing**: it should be possible to "preprocess" /
"compile" / "crunch" assets at "development time" rather than when the
game starts up. This enables offloading expensive work from deployed
apps, faster asset loading, less runtime memory usage, etc.
* **Per-Asset Loader Settings**: Individual assets cannot define their
own loaders that override the defaults. Additionally, they cannot
provide per-asset settings to their loaders. This is a huge limitation,
as many asset types don't provide all information necessary for Bevy
_inside_ the asset. For example, a raw PNG image says nothing about how
it should be sampled (ex: linear vs nearest).
* **Asset `.meta` files**: assets should have configuration files stored
adjacent to the asset in question, which allows the user to configure
asset-type-specific settings. These settings should be accessible during
the pre-processing phase. Modifying a `.meta` file should trigger a
re-processing / re-load of the asset. It should be possible to configure
asset loaders from the meta file.
* **Processed Asset Hot Reloading**: Changes to processed assets (or
their dependencies) should result in re-processing them and re-loading
the results in live Bevy Apps.
* **Asset Dependency Tracking**: The current bevy_asset has no good way
to wait for asset dependencies to load. It punts this as an exercise for
consumers of the loader apis, which is unreasonable and error prone.
There should be easy, ergonomic ways to wait for assets to load and
block some logic on an asset's entire dependency tree loading.
* **Runtime Asset Loading**: it should be (optionally) possible to load
arbitrary assets dynamically at runtime. This necessitates being able to
deploy and run the asset server alongside Bevy Apps on _all platforms_.
For example, we should be able to invoke the shader compiler at runtime,
stream scenes from sources like the internet, etc. To keep deployed
binaries (and startup times) small, the runtime asset server
configuration should be configurable with different settings compared to
the "pre processor asset server".
* **Multiple Backends**: It should be possible to load assets from
arbitrary sources (filesystems, the internet, remote asset serves, etc).
* **Asset Packing**: It should be possible to deploy assets in
compressed "packs", which makes it easier and more efficient to
distribute assets with Bevy Apps.
* **Asset Handoff**: It should be possible to hold a "live" asset
handle, which correlates to runtime data, without actually holding the
asset in memory. Ex: it must be possible to hold a reference to a GPU
mesh generated from a "mesh asset" without keeping the mesh data in CPU
memory
* **Per-Platform Processed Assets**: Different platforms and app
distributions have different capabilities and requirements. Some
platforms need lower asset resolutions or different asset formats to
operate within the hardware constraints of the platform. It should be
possible to define per-platform asset processing profiles. And it should
be possible to deploy only the assets required for a given platform.

These features have architectural implications that are significant
enough to require a full rewrite. The current Bevy Asset implementation
got us this far, but it can take us no farther. This PR defines a brand
new asset system that implements most of these features, while laying
the foundations for the remaining features to be built.

## Bevy Asset V2

Here is a quick overview of the features introduced in this PR.
* **Asset Preprocessing**: Preprocess assets at development time into
more efficient (and configurable) representations
* **Dependency Aware**: Dependencies required to process an asset are
tracked. If an asset's processed dependency changes, it will be
reprocessed
* **Hot Reprocessing/Reloading**: detect changes to asset source files,
reprocess them if they have changed, and then hot-reload them in Bevy
Apps.
* **Only Process Changes**: Assets are only re-processed when their
source file (or meta file) has changed. This uses hashing and timestamps
to avoid processing assets that haven't changed.
* **Transactional and Reliable**: Uses write-ahead logging (a technique
commonly used by databases) to recover from crashes / forced-exits.
Whenever possible it avoids full-reprocessing / only uncompleted
transactions will be reprocessed. When the processor is running in
parallel with a Bevy App, processor asset writes block Bevy App asset
reads. Reading metadata + asset bytes is guaranteed to be transactional
/ correctly paired.
* **Portable / Run anywhere / Database-free**: The processor does not
rely on an in-memory database (although it uses some database techniques
for reliability). This is important because pretty much all in-memory
databases have unsupported platforms or build complications.
* **Configure Processor Defaults Per File Type**: You can say "use this
processor for all files of this type".
* **Custom Processors**: The `Processor` trait is flexible and
unopinionated. It can be implemented by downstream plugins.
* **LoadAndSave Processors**: Most asset processing scenarios can be
expressed as "run AssetLoader A, save the results using AssetSaver X,
and then load the result using AssetLoader B". For example, load this
png image using `PngImageLoader`, which produces an `Image` asset and
then save it using `CompressedImageSaver` (which also produces an
`Image` asset, but in a compressed format), which takes an `Image` asset
as input. This means if you have an `AssetLoader` for an asset, you are
already half way there! It also means that you can share AssetSavers
across multiple loaders. Because `CompressedImageSaver` accepts Bevy's
generic Image asset as input, it means you can also use it with some
future `JpegImageLoader`.
* **Loader and Saver Settings**: Asset Loaders and Savers can now define
their own settings types, which are passed in as input when an asset is
loaded / saved. Each asset can define its own settings.
* **Asset `.meta` files**: configure asset loaders, their settings,
enable/disable processing, and configure processor settings
* **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex:
if an asset contains a `Handle<Image>`) are tracked by the asset server.
An event is emitted when an asset and all of its dependencies have been
loaded
* **Unprocessed Asset Loading**: Assets do not require preprocessing.
They can be loaded directly. A processed asset is just a "normal" asset
with some extra metadata. Asset Loaders don't need to know or care about
whether or not an asset was processed.
* **Async Asset IO**: Asset readers/writers use async non-blocking
interfaces. Note that because Rust doesn't yet support async traits,
there is a bit of manual Boxing / Future boilerplate. This will
hopefully be removed in the near future when Rust gets async traits.
* **Pluggable Asset Readers and Writers**: Arbitrary asset source
readers/writers are supported, both by the processor and the asset
server.
* **Better Asset Handles**
* **Single Arc Tree**: Asset Handles now use a single arc tree that
represents the lifetime of the asset. This makes their implementation
simpler, more efficient, and allows us to cheaply attach metadata to
handles. Ex: the AssetPath of a handle is now directly accessible on the
handle itself!
* **Const Typed Handles**: typed handles can be constructed in a const
context. No more weird "const untyped converted to typed at runtime"
patterns!
* **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed
`Handle<T>` is now much smaller in memory and `AssetId<T>` is even
smaller.
* **Weak Handle Usage Reduction**: In general Handles are now considered
to be "strong". Bevy features that previously used "weak `Handle<T>`"
have been ported to `AssetId<T>`, which makes it statically clear that
the features do not hold strong handles (while retaining strong type
information). Currently Handle::Weak still exists, but it is very
possible that we can remove that entirely.
* **Efficient / Dense Asset Ids**: Assets now have efficient dense
runtime asset ids, which means we can avoid expensive hash lookups.
Assets are stored in Vecs instead of HashMaps. There are now typed and
untyped ids, which means we no longer need to store dynamic type
information in the ID for typed handles. "AssetPathId" (which was a
nightmare from a performance and correctness standpoint) has been
entirely removed in favor of dense ids (which are retrieved for a path
on load)
* **Direct Asset Loading, with Dependency Tracking**: Assets that are
defined at runtime can still have their dependencies tracked by the
Asset Server (ex: if you create a material at runtime, you can still
wait for its textures to load). This is accomplished via the (currently
optional) "asset dependency visitor" trait. This system can also be used
to define a set of assets to load, then wait for those assets to load.
* **Async folder loading**: Folder loading also uses this system and
immediately returns a handle to the LoadedFolder asset, which means
folder loading no longer blocks on directory traversals.
* **Improved Loader Interface**: Loaders now have a specific "top level
asset type", which makes returning the top-level asset simpler and
statically typed.
* **Basic Image Settings and Processing**: Image assets can now be
processed into the gpu-friendly Basic Universal format. The ImageLoader
now has a setting to define what format the image should be loaded as.
Note that this is just a minimal MVP ... plenty of additional work to do
here. To demo this, enable the `basis-universal` feature and turn on
asset processing.
* **Simpler Audio Play / AudioSink API**: Asset handle providers are
cloneable, which means the Audio resource can mint its own handles. This
means you can now do `let sink_handle = audio.play(music)` instead of
`let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that
this might still be replaced by
https://github.com/bevyengine/bevy/pull/8424.
**Removed Handle Casting From Engine Features**: Ex: FontAtlases no
longer use casting between handle types

## Using The New Asset System

### Normal Unprocessed Asset Loading

By default the `AssetPlugin` does not use processing. It behaves pretty
much the same way as the old system.

If you are defining a custom asset, first derive `Asset`:

```rust
#[derive(Asset)]
struct Thing {
    value: String,
}
```

Initialize the asset:
```rust
app.init_asset:<Thing>()
```

Implement a new `AssetLoader` for it:

```rust
#[derive(Default)]
struct ThingLoader;

#[derive(Serialize, Deserialize, Default)]
pub struct ThingSettings {
    some_setting: bool,
}

impl AssetLoader for ThingLoader {
    type Asset = Thing;
    type Settings = ThingSettings;

    fn load<'a>(
        &'a self,
        reader: &'a mut Reader,
        settings: &'a ThingSettings,
        load_context: &'a mut LoadContext,
    ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> {
        Box::pin(async move {
            let mut bytes = Vec::new();
            reader.read_to_end(&mut bytes).await?;
            // convert bytes to value somehow
            Ok(Thing {
                value 
            })
        })
    }

    fn extensions(&self) -> &[&str] {
        &["thing"]
    }
}
```

Note that this interface will get much cleaner once Rust gets support
for async traits. `Reader` is an async futures_io::AsyncRead. You can
stream bytes as they come in or read them all into a `Vec<u8>`,
depending on the context. You can use `let handle =
load_context.load(path)` to kick off a dependency load, retrieve a
handle, and register the dependency for the asset.

Then just register the loader in your Bevy app:

```rust
app.init_asset_loader::<ThingLoader>()
```

Now just add your `Thing` asset files into the `assets` folder and load
them like this:

```rust
fn system(asset_server: Res<AssetServer>) {
    let handle = Handle<Thing> = asset_server.load("cool.thing");
}
```

You can check load states directly via the asset server:

```rust
if asset_server.load_state(&handle) == LoadState::Loaded { }
```

You can also listen for events:

```rust
fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) {
    for event in events.iter() {
        if event.is_loaded_with_dependencies(&handle) {
        }
    }
}
```

Note the new `AssetEvent::LoadedWithDependencies`, which only fires when
the asset is loaded _and_ all dependencies (and their dependencies) have
loaded.

Unlike the old asset system, for a given asset path all `Handle<T>`
values point to the same underlying Arc. This means Handles can cheaply
hold more asset information, such as the AssetPath:

```rust
// prints the AssetPath of the handle
info!("{:?}", handle.path())
```

### Processed Assets

Asset processing can be enabled via the `AssetPlugin`. When developing
Bevy Apps with processed assets, do this:

```rust
app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))
```

This runs the `AssetProcessor` in the background with hot-reloading. It
reads assets from the `assets` folder, processes them, and writes them
to the `.imported_assets` folder. Asset loads in the Bevy App will wait
for a processed version of the asset to become available. If an asset in
the `assets` folder changes, it will be reprocessed and hot-reloaded in
the Bevy App.

When deploying processed Bevy apps, do this:

```rust
app.add_plugins(DefaultPlugins.set(AssetPlugin::processed()))
```

This does not run the `AssetProcessor` in the background. It behaves
like `AssetPlugin::unprocessed()`, but reads assets from
`.imported_assets`.

When the `AssetProcessor` is running, it will populate sibling `.meta`
files for assets in the `assets` folder. Meta files for assets that do
not have a processor configured look like this:

```rust
(
    meta_format_version: "1.0",
    asset: Load(
        loader: "bevy_render::texture::image_loader::ImageLoader",
        settings: (
            format: FromExtension,
        ),
    ),
)
```

This is metadata for an image asset. For example, if you have
`assets/my_sprite.png`, this could be the metadata stored at
`assets/my_sprite.png.meta`. Meta files are totally optional. If no
metadata exists, the default settings will be used.

In short, this file says "load this asset with the ImageLoader and use
the file extension to determine the image type". This type of meta file
is supported in all AssetPlugin modes. If in `Unprocessed` mode, the
asset (with the meta settings) will be loaded directly. If in
`ProcessedDev` mode, the asset file will be copied directly to the
`.imported_assets` folder. The meta will also be copied directly to the
`.imported_assets` folder, but with one addition:

```rust
(
    meta_format_version: "1.0",
    processed_info: Some((
        hash: 12415480888597742505,
        full_hash: 14344495437905856884,
        process_dependencies: [],
    )),
    asset: Load(
        loader: "bevy_render::texture::image_loader::ImageLoader",
        settings: (
            format: FromExtension,
        ),
    ),
)
```

`processed_info` contains `hash` (a direct hash of the asset and meta
bytes), `full_hash` (a hash of `hash` and the hashes of all
`process_dependencies`), and `process_dependencies` (the `path` and
`full_hash` of every process_dependency). A "process dependency" is an
asset dependency that is _directly_ used when processing the asset.
Images do not have process dependencies, so this is empty.

When the processor is enabled, you can use the `Process` metadata
config:

```rust
(
    meta_format_version: "1.0",
    asset: Process(
        processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>",
        settings: (
            loader_settings: (
                format: FromExtension,
            ),
            saver_settings: (
                generate_mipmaps: true,
            ),
        ),
    ),
)
```

This configures the asset to use the `LoadAndSave` processor, which runs
an AssetLoader and feeds the result into an AssetSaver (which saves the
given Asset and defines a loader to load it with). (for terseness
LoadAndSave will likely get a shorter/friendlier type name when [Stable
Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common
processor type, but arbitrary processors are supported.

`CompressedImageSaver` saves an `Image` in the Basis Universal format
and configures the ImageLoader to load it as basis universal. The
`AssetProcessor` will read this meta, run it through the LoadAndSave
processor, and write the basis-universal version of the image to
`.imported_assets`. The final metadata will look like this:

```rust
(
    meta_format_version: "1.0",
    processed_info: Some((
        hash: 905599590923828066,
        full_hash: 9948823010183819117,
        process_dependencies: [],
    )),
    asset: Load(
        loader: "bevy_render::texture::image_loader::ImageLoader",
        settings: (
            format: Format(Basis),
        ),
    ),
)
```

To try basis-universal processing out in Bevy examples, (for example
`sprite.rs`), change `add_plugins(DefaultPlugins)` to
`add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run
with the `basis-universal` feature enabled: `cargo run
--features=basis-universal --example sprite`.

To create a custom processor, there are two main paths:
1. Use the `LoadAndSave` processor with an existing `AssetLoader`.
Implement the `AssetSaver` trait, register the processor using
`asset_processor.register_processor::<LoadAndSave<ImageLoader,
CompressedImageSaver>>(image_saver.into())`.
2. Implement the `Process` trait directly and register it using:
`asset_processor.register_processor(thing_processor)`.

You can configure default processors for file extensions like this:

```rust
asset_processor.set_default_processor::<ThingProcessor>("thing")
```

There is one more metadata type to be aware of:

```rust
(
    meta_format_version: "1.0",
    asset: Ignore,
)
```

This will ignore the asset during processing / prevent it from being
written to `.imported_assets`.

The AssetProcessor stores a transaction log at `.imported_assets/log`
and uses it to gracefully recover from unexpected stops. This means you
can force-quit the processor (and Bevy Apps running the processor in
parallel) at arbitrary times!

`.imported_assets` is "local state". It should _not_ be checked into
source control. It should also be considered "read only". In practice,
you _can_ modify processed assets and processed metadata if you really
need to test something. But those modifications will not be represented
in the hashes of the assets, so the processed state will be "out of
sync" with the source assets. The processor _will not_ fix this for you.
Either revert the change after you have tested it, or delete the
processed files so they can be re-populated.

## Open Questions

There are a number of open questions to be discussed. We should decide
if they need to be addressed in this PR and if so, how we will address
them:

### Implied Dependencies vs Dependency Enumeration

There are currently two ways to populate asset dependencies:
* **Implied via AssetLoaders**: if an AssetLoader loads an asset (and
retrieves a handle), a dependency is added to the list.
* **Explicit via the optional Asset::visit_dependencies**: if
`server.load_asset(my_asset)` is called, it will call
`my_asset.visit_dependencies`, which will grab dependencies that have
been manually defined for the asset via the Asset trait impl (which can
be derived).

This means that defining explicit dependencies is optional for "loaded
assets". And the list of dependencies is always accurate because loaders
can only produce Handles if they register dependencies. If an asset was
loaded with an AssetLoader, it only uses the implied dependencies. If an
asset was created at runtime and added with
`asset_server.load_asset(MyAsset)`, it will use
`Asset::visit_dependencies`.

However this can create a behavior mismatch between loaded assets and
equivalent "created at runtime" assets if `Assets::visit_dependencies`
doesn't exactly match the dependencies produced by the AssetLoader. This
behavior mismatch can be resolved by completely removing "implied loader
dependencies" and requiring `Asset::visit_dependencies` to supply
dependency data. But this creates two problems:
* It makes defining loaded assets harder and more error prone: Devs must
remember to manually annotate asset dependencies with `#[dependency]`
when deriving `Asset`. For more complicated assets (such as scenes), the
derive likely wouldn't be sufficient and a manual `visit_dependencies`
impl would be required.
* Removes the ability to immediately kick off dependency loads: When
AssetLoaders retrieve a Handle, they also immediately kick off an asset
load for the handle, which means it can start loading in parallel
_before_ the asset finishes loading. For large assets, this could be
significant. (although this could be mitigated for processed assets if
we store dependencies in the processed meta file and load them ahead of
time)

### Eager ProcessorDev Asset Loading

I made a controversial call in the interest of fast startup times ("time
to first pixel") for the "processor dev mode configuration". When
initializing the AssetProcessor, current processed versions of unchanged
assets are yielded immediately, even if their dependencies haven't been
checked yet for reprocessing. This means that
non-current-state-of-filesystem-but-previously-valid assets might be
returned to the App first, then hot-reloaded if/when their dependencies
change and the asset is reprocessed.

Is this behavior desirable? There is largely one alternative: do not
yield an asset from the processor to the app until all of its
dependencies have been checked for changes. In some common cases (load
dependency has not changed since last run) this will increase startup
time. The main question is "by how much" and is that slower startup time
worth it in the interest of only yielding assets that are true to the
current state of the filesystem. Should this be configurable? I'm
starting to think we should only yield an asset after its (historical)
dependencies have been checked for changes + processed as necessary, but
I'm curious what you all think.

### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs?

In this implementation AssetPaths are the only canonical asset
identifier (just like the previous Bevy Asset system and Godot). Moving
assets will result in re-scans (and currently reprocessing, although
reprocessing can easily be avoided with some changes). Asset
renames/moves will break code and assets that rely on specific paths,
unless those paths are fixed up.

Do we want / need "stable asset uuids"? Introducing them is very
possible:
1. Generate a UUID and include it in .meta files
2. Support UUID in AssetPath
3. Generate "asset indices" which are loaded on startup and map UUIDs to
paths.
4 (maybe). Consider only supporting UUIDs for processed assets so we can
generate quick-to-load indices instead of scanning meta files.

The main "pro" is that assets referencing UUIDs don't need to be
migrated when a path changes. The main "con" is that UUIDs cannot be
"lazily resolved" like paths. They need a full view of all assets to
answer the question "does this UUID exist". Which means UUIDs require
the AssetProcessor to fully finish startup scans before saying an asset
doesnt exist. And they essentially require asset pre-processing to use
in apps, because scanning all asset metadata files at runtime to resolve
a UUID is not viable for medium-to-large apps. It really requires a
pre-generated UUID index, which must be loaded before querying for
assets.

I personally think this should be investigated in a separate PR. Paths
aren't going anywhere ... _everyone_ uses filesystems (and
filesystem-like apis) to manage their asset source files. I consider
them permanent canonical asset information. Additionally, they behave
well for both processed and unprocessed asset modes. Given that Bevy is
supporting both, this feels like the right canonical ID to start with.
UUIDS (and maybe even other indexed-identifier types) can be added later
as necessary.

### Folder / File Naming Conventions

All asset processing config currently lives in the `.imported_assets`
folder. The processor transaction log is in `.imported_assets/log`.
Processed assets are added to `.imported_assets/Default`, which will
make migrating to processed asset profiles (ex: a
`.imported_assets/Mobile` profile) a non-breaking change. It also allows
us to create top-level files like `.imported_assets/log` without it
being interpreted as an asset. Meta files currently have a `.meta`
suffix. Do we like these names and conventions?

### Should the `AssetPlugin::processed_dev` configuration enable
`watch_for_changes` automatically?

Currently it does (which I think makes sense), but it does make it the
only configuration that enables watch_for_changes by default.

### Discuss on_loaded High Level Interface:

This PR includes a very rough "proof of concept" `on_loaded` system
adapter that uses the `LoadedWithDependencies` event in combination with
`asset_server.load_asset` dependency tracking to support this pattern

```rust
fn main() {
    App::new()
        .init_asset::<MyAssets>()
        .add_systems(Update, on_loaded(create_array_texture))
        .run();
}

#[derive(Asset, Clone)]
struct MyAssets {
    #[dependency]
    picture_of_my_cat: Handle<Image>,
    #[dependency]
    picture_of_my_other_cat: Handle<Image>,
}

impl FromWorld for ArrayTexture {
    fn from_world(world: &mut World) -> Self {
        picture_of_my_cat: server.load("meow.png"),
        picture_of_my_other_cat: server.load("meeeeeeeow.png"),
    }
}

fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) {
    commands.spawn(SpriteBundle {
        texture: my_assets.picture_of_my_cat.clone(),  
        ..default()
    });
    
    commands.spawn(SpriteBundle {
        texture: my_assets.picture_of_my_other_cat.clone(),  
        ..default()
    });
}

```

The implementation is _very_ rough. And it is currently unsafe because
`bevy_ecs` doesn't expose some internals to do this safely from inside
`bevy_asset`. There are plenty of unanswered questions like:
* "do we add a Loadable" derive? (effectively automate the FromWorld
implementation above)
* Should `MyAssets` even be an Asset? (largely implemented this way
because it elegantly builds on `server.load_asset(MyAsset { .. })`
dependency tracking).

We should think hard about what our ideal API looks like (and if this is
a pattern we want to support). Not necessarily something we need to
solve in this PR. The current `on_loaded` impl should probably be
removed from this PR before merging.

## Clarifying Questions

### What about Assets as Entities?

This Bevy Asset V2 proposal implementation initially stored Assets as
ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used
`Entity` as the asset id and Asset values were just ECS components.
There are plenty of compelling reasons to do this:
1. Easier to inline assets in Bevy Scenes (as they are "just" normal
entities + components)
2. More flexible queries: use the power of the ECS to filter assets (ex:
`Query<Mesh, With<Tree>>`).
3. Extensible. Users can add arbitrary component data to assets.
4. Things like "component visualization tools" work out of the box to
visualize asset data.

However Assets as Entities has a ton of caveats right now:
* We need to be able to allocate entity ids without a direct World
reference (aka rework id allocator in Entities ... i worked around this
in my prototypes by just pre allocating big chunks of entities)
* We want asset change events in addition to ECS change tracking ... how
do we populate them when mutations can come from anywhere? Do we use
Changed queries? This would require iterating over the change data for
all assets every frame. Is this acceptable or should we implement a new
"event based" component change detection option?
* Reconciling manually created assets with asset-system managed assets
has some nuance (ex: are they "loaded" / do they also have that
component metadata?)
* "how do we handle "static" / default entity handles" (ties in to the
Entity Indices discussion:
https://github.com/bevyengine/bevy/discussions/8319). This is necessary
for things like "built in" assets and default handles in things like
SpriteBundle.
* Storing asset information as a component makes it easy to "invalidate"
asset state by removing the component (or forcing modifications).
Ideally we have ways to lock this down (some combination of Rust type
privacy and ECS validation)

In practice, how we store and identify assets is a reasonably
superficial change (porting off of Assets as Entities and implementing
dedicated storage + ids took less than a day). So once we sort out the
remaining challenges the flip should be straightforward. Additionally, I
do still have "Assets as Entities" in my commit history, so we can reuse
that work. I personally think "assets as entities" is a good endgame,
but it also doesn't provide _significant_ value at the moment and it
certainly isn't ready yet with the current state of things.

### Why not Distill?

[Distill](https://github.com/amethyst/distill) is a high quality fully
featured asset system built in Rust. It is very natural to ask "why not
just use Distill?".

It is also worth calling out that for awhile, [we planned on adopting
Distill / I signed off on
it](https://github.com/bevyengine/bevy/issues/708).

However I think Bevy has a number of constraints that make Distill
adoption suboptimal:
* **Architectural Simplicity:**
* Distill's processor requires an in-memory database (lmdb) and RPC
networked API (using Cap'n Proto). Each of these introduces API
complexity that increases maintenance burden and "code grokability".
Ignoring tests, documentation, and examples, Distill has 24,237 lines of
Rust code (including generated code for RPC + database interactions). If
you ignore generated code, it has 11,499 lines.
* Bevy builds the AssetProcessor and AssetServer using pluggable
AssetReader/AssetWriter Rust traits with simple io interfaces. They do
not necessitate databases or RPC interfaces (although Readers/Writers
could use them if that is desired). Bevy Asset V2 (at the time of
writing this PR) is 5,384 lines of Rust code (ignoring tests,
documentation, and examples). Grain of salt: Distill does have more
features currently (ex: Asset Packing, GUIDS, remote-out-of-process
asset processor). I do plan to implement these features in Bevy Asset V2
and I personally highly doubt they will meaningfully close the 6115
lines-of-code gap.
* This complexity gap (which while illustrated by lines of code, is much
bigger than just that) is noteworthy to me. Bevy should be hackable and
there are pillars of Distill that are very hard to understand and
extend. This is a matter of opinion (and Bevy Asset V2 also has
complicated areas), but I think Bevy Asset V2 is much more approachable
for the average developer.
* Necessary disclaimer: counting lines of code is an extremely rough
complexity metric. Read the code and form your own opinions.
* **Optional Asset Processing:** Not all Bevy Apps (or Bevy App
developers) need / want asset preprocessing. Processing increases the
complexity of the development environment by introducing things like
meta files, imported asset storage, running processors in the
background, waiting for processing to finish, etc. Distill _requires_
preprocessing to work. With Bevy Asset V2 processing is fully opt-in.
The AssetServer isn't directly aware of asset processors at all.
AssetLoaders only care about converting bytes to runtime Assets ... they
don't know or care if the bytes were pre-processed or not. Processing is
"elegantly" (forgive my self-congratulatory phrasing) layered on top and
builds on the existing Asset system primitives.
* **Direct Filesystem Access to Processed Asset State:** Distill stores
processed assets in a database. This makes debugging / inspecting the
processed outputs harder (either requires special tooling to query the
database or they need to be "deployed" to be inspected). Bevy Asset V2,
on the other hand, stores processed assets in the filesystem (by default
... this is configurable). This makes interacting with the processed
state more natural. Note that both Godot and Unity's new asset system
store processed assets in the filesystem.
* **Portability**: Because Distill's processor uses lmdb and RPC
networking, it cannot be run on certain platforms (ex: lmdb is a
non-rust dependency that cannot run on the web, some platforms don't
support running network servers). Bevy should be able to process assets
everywhere (ex: run the Bevy Editor on the web, compile + process
shaders on mobile, etc). Distill does partially mitigate this problem by
supporting "streaming" assets via the RPC protocol, but this is not a
full solve from my perspective. And Bevy Asset V2 can (in theory) also
stream assets (without requiring RPC, although this isn't implemented
yet)

Note that I _do_ still think Distill would be a solid asset system for
Bevy. But I think the approach in this PR is a better solve for Bevy's
specific "asset system requirements".

### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the
point?

"True async file io" has limited / spotty platform support. async-fs
(and the rust async ecosystem generally ... ex Tokio) currently use
async wrappers over std::fs that offload blocking requests to separate
threads. This may feel unsatisfying, but it _does_ still provide value
because it prevents our task pools from blocking on file system
operations (which would prevent progress when there are many tasks to
do, but all threads in a pool are currently blocking on file system
ops).

Additionally, using async APIs for our AssetReaders and AssetWriters
also provides value because we can later add support for "true async
file io" for platforms that support it. _And_ we can implement other
"true async io" asset backends (such as networked asset io).

## Draft TODO

- [x] Fill in missing filesystem event APIs: file removed event (which
is expressed as dangling RenameFrom events in some cases), file/folder
renamed event
- [x] Assets without loaders are not moved to the processed folder. This
breaks things like referenced `.bin` files for GLTFs. This should be
configurable per-non-asset-type.
- [x] Initial implementation of Reflect and FromReflect for Handle. The
"deserialization" parity bar is low here as this only worked with static
UUIDs in the old impl ... this is a non-trivial problem. Either we add a
Handle::AssetPath variant that gets "upgraded" to a strong handle on
scene load or we use a separate AssetRef type for Bevy scenes (which is
converted to a runtime Handle on load). This deserves its own discussion
in a different pr.
- [x] Populate read_asset_bytes hash when run by the processor (a bit of
a special case .. when run by the processor the processed meta will
contain the hash so we don't need to compute it on the spot, but we
don't want/need to read the meta when run by the main AssetServer)
- [x] Delay hot reloading: currently filesystem events are handled
immediately, which creates timing issues in some cases. For example hot
reloading images can sometimes break because the image isn't finished
writing. We should add a delay, likely similar to the [implementation in
this PR](https://github.com/bevyengine/bevy/pull/8503).
- [x] Port old platform-specific AssetIo implementations to the new
AssetReader interface (currently missing Android and web)
- [x] Resolve on_loaded unsafety (either by removing the API entirely or
removing the unsafe)
- [x]  Runtime loader setting overrides
- [x] Remove remaining unwraps that should be error-handled. There are
number of TODOs here
- [x] Pretty AssetPath Display impl
- [x] Document more APIs
- [x] Resolve spurious "reloading because it has changed" events (to
repro run load_gltf with `processed_dev()`)
- [x] load_dependency hot reloading currently only works for processed
assets. If processing is disabled, load_dependency changes are not hot
reloaded.
- [x] Replace AssetInfo dependency load/fail counters with
`loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from
(potentially) breaking counters. Storing this will also enable
"dependency reloaded" events (see [Next Steps](#next-steps))
- [x] Re-add filesystem watcher cargo feature gate (currently it is not
optional)
- [ ] Migration Guide
- [ ] Changelog

## Followup TODO

- [ ] Replace "eager unchanged processed asset loading" behavior with
"don't returned unchanged processed asset until dependencies have been
checked".
- [ ] Add true `Ignore` AssetAction that does not copy the asset to the
imported_assets folder.
- [ ] Finish "live asset unloading" (ex: free up CPU asset memory after
uploading an image to the GPU), rethink RenderAssets, and port renderer
features. The `Assets` collection uses `Option<T>` for asset storage to
support its removal. (1) the Option might not actually be necessary ...
might be able to just remove from the collection entirely (2) need to
finalize removal apis
- [ ] Try replacing the "channel based" asset id recycling with
something a bit more efficient (ex: we might be able to use raw atomic
ints with some cleverness)
- [ ] Consider adding UUIDs to processed assets (scoped just to helping
identify moved assets ... not exposed to load queries ... see [Next
Steps](#next-steps))
- [ ] Store "last modified" source asset and meta timestamps in
processed meta files to enable skipping expensive hashing when the file
wasn't changed
- [ ] Fix "slow loop" handle drop fix 
- [ ] Migrate to TypeName
- [x] Handle "loader preregistration". See #9429

## Next Steps

* **Configurable per-type defaults for AssetMeta**: It should be
possible to add configuration like "all png image meta should default to
using nearest sampling" (currently this hard-coded per-loader/processor
Settings::default() impls). Also see the "Folder Meta" bullet point.
* **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical
asset ids" discussion in [Open Questions](#open-questions) and the
relevant bullet point in [Draft TODO](#draft-todo). Even without
canonical ids, folder renames could avoid reprocessing in some cases.
* **Multiple Asset Sources**: Expand AssetPath to support "asset source
names" and support multiple AssetReaders in the asset server (ex:
`webserver://some_path/image.png` backed by an Http webserver
AssetReader). The "default" asset reader would use normal
`some_path/image.png` paths. Ideally this works in combination with
multiple AssetWatchers for hot-reloading
* **Stable Type Names**: this pr removes the TypeUuid requirement from
assets in favor of `std::any::type_name`. This makes defining assets
easier (no need to generate a new uuid / use weird proc macro syntax).
It also makes reading meta files easier (because things have "friendly
names"). We also use type names for components in scene files. If they
are good enough for components, they are good enough for assets. And
consistency across Bevy pillars is desirable. However,
`std::any::type_name` is not guaranteed to be stable (although in
practice it is). We've developed a [stable type
path](https://github.com/bevyengine/bevy/pull/7184) to resolve this,
which should be adopted when it is ready.
* **Command Line Interface**: It should be possible to run the asset
processor in a separate process from the command line. This will also
require building a network-server-backed AssetReader to communicate
between the app and the processor. We've been planning to build a "bevy
cli" for awhile. This seems like a good excuse to build it.
* **Asset Packing**: This is largely an additive feature, so it made
sense to me to punt this until we've laid the foundations in this PR.
* **Per-Platform Processed Assets**: It should be possible to generate
assets for multiple platforms by supporting multiple "processor
profiles" per asset (ex: compress with format X on PC and Y on iOS). I
think there should probably be arbitrary "profiles" (which can be
separate from actual platforms), which are then assigned to a given
platform when generating the final asset distribution for that platform.
Ex: maybe devs want a "Mobile" profile that is shared between iOS and
Android. Or a "LowEnd" profile shared between web and mobile.
* **Versioning and Migrations**: Assets, Loaders, Savers, and Processors
need to have versions to determine if their schema is valid. If an asset
/ loader version is incompatible with the current version expected at
runtime, the processor should be able to migrate them. I think we should
try using Bevy Reflect for this, as it would allow us to load the old
version as a dynamic Reflect type without actually having the old Rust
type. It would also allow us to define "patches" to migrate between
versions (Bevy Reflect devs are currently working on patching). The
`.meta` file already has its own format version. Migrating that to new
versions should also be possible.
* **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write
type) currently used by AssetPath can still result in String clones that
aren't actually necessary (cloning an Owned Cow clones the contents).
Bevy's asset system requires cloning AssetPaths in a number of places,
which result in actual clones of the internal Strings. This is not
efficient. AssetPath internals should be reworked to exhibit truer
cow-like-behavior that reduces String clones to the absolute minimum.
* **Consider processor-less processing**: In theory the AssetServer
could run processors "inline" even if the background AssetProcessor is
disabled. If we decide this is actually desirable, we could add this.
But I don't think its a priority in the short or medium term.
* **Pre-emptive dependency loading**: We could encode dependencies in
processed meta files, which could then be used by the Asset Server to
kick of dependency loads as early as possible (prior to starting the
actual asset load). Is this desirable? How much time would this save in
practice?
* **Optimize Processor With UntypedAssetIds**: The processor exclusively
uses AssetPath to identify assets currently. It might be possible to
swap these out for UntypedAssetIds in some places, which are smaller /
cheaper to hash and compare.
* **One to Many Asset Processing**: An asset source file that produces
many assets currently must be processed into a single "processed" asset
source. If labeled assets can be written separately they can each have
their own configured savers _and_ they could be loaded more granularly.
Definitely worth exploring!
* **Automatically Track "Runtime-only" Asset Dependencies**: Right now,
tracking "created at runtime" asset dependencies requires adding them
via `asset_server.load_asset(StandardMaterial::default())`. I think with
some cleverness we could also do this for
`materials.add(StandardMaterial::default())`, making tracking work
"everywhere". There are challenges here relating to change detection /
ensuring the server is made aware of dependency changes. This could be
expensive in some cases.
* **"Dependency Changed" events**: Some assets have runtime artifacts
that need to be re-generated when one of their dependencies change (ex:
regenerate a material's bind group when a Texture needs to change). We
are generating the dependency graph so we can definitely produce these
events. Buuuuut generating these events will have a cost / they could be
high frequency for some assets, so we might want this to be opt-in for
specific cases.
* **Investigate Storing More Information In Handles**: Handles can now
store arbitrary information, which makes it cheaper and easier to
access. How much should we move into them? Canonical asset load states
(via atomics)? (`handle.is_loaded()` would be very cool). Should we
store the entire asset and remove the `Assets<T>` collection?
(`Arc<RwLock<Option<Image>>>`?)
* **Support processing and loading files without extensions**: This is a
pretty arbitrary restriction and could be supported with very minimal
changes.
* **Folder Meta**: It would be nice if we could define per folder
processor configuration defaults (likely in a `.meta` or `.folder_meta`
file). Things like "default to linear filtering for all Images in this
folder".
* **Replace async_broadcast with event-listener?** This might be
approximately drop-in for some uses and it feels more light weight
* **Support Running the AssetProcessor on the Web**: Most of the hard
work is done here, but there are some easy straggling TODOs (make the
transaction log an interface instead of a direct file writer so we can
write a web storage backend, implement an AssetReader/AssetWriter that
reads/writes to something like LocalStorage).
* **Consider identifying and preventing circular dependencies**: This is
especially important for "processor dependencies", as processing will
silently never finish in these cases.
* **Built-in/Inlined Asset Hot Reloading**: This PR regresses
"built-in/inlined" asset hot reloading (previously provided by the
DebugAssetServer). I'm intentionally punting this because I think it can
be cleanly implemented with "multiple asset sources" by registering a
"debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset
paths) in combination with an AssetWatcher for that asset source and
support for "manually loading pats with asset bytes instead of
AssetReaders". The old DebugAssetServer was quite nasty and I'd love to
avoid that hackery going forward.
* **Investigate ways to remove double-parsing meta files**: Parsing meta
files currently involves parsing once with "minimal" versions of the
meta file to extract the type name of the loader/processor config, then
parsing again to parse the "full" meta. This is suboptimal. We should be
able to define custom deserializers that (1) assume the loader/processor
type name comes first (2) dynamically looks up the loader/processor
registrations to deserialize settings in-line (similar to components in
the bevy scene format). Another alternative: deserialize as dynamic
Reflect objects and then convert.
* **More runtime loading configuration**: Support using the Handle type
as a hint to select an asset loader (instead of relying on AssetPath
extensions)
* **More high level Processor trait implementations**: For example, it
might be worth adding support for arbitrary chains of "asset transforms"
that modify an in-memory asset representation between loading and
saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by
a `flip_normals` transform, then save the mesh to an efficient
compressed format).
* **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO
item](#draft-todo) for context)
* **Explore High Level Load Interfaces**: See [this
discussion](#discuss-on_loaded-high-level-interface) for one prototype.
* **Asset Streaming**: It would be great if we could stream Assets (ex:
stream a long video file piece by piece)
* **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than
they need to be because they have a Uuid enum variant. If we implement
an "id exchanging" system that trades Uuids for "efficient runtime ids",
we can cut down on the size of AssetIds, making them more efficient.
This has some open design questions, such as how to spawn entities with
"default" handle values (as these wouldn't have access to the exchange
api in the current system).
* **Asset Path Fixup Tooling**: Assets that inline asset paths inside
them will break when an asset moves. The asset system provides the
functionality to detect when paths break. We should build a framework
that enables formats to define "path migrations". This is especially
important for scene files. For editor-generated files, we should also
consider using UUIDs (see other bullet point) to avoid the need to
migrate in these cases.

---------

Co-authored-by: BeastLe9enD <beastle9end@outlook.de>
Co-authored-by: Mike <mike.hsu@gmail.com>
Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
JMS55
228e7aa618
Add support for KHR_materials_emissive_strength (#9553)
# Objective

- Fix blender gltf imports with emissive materials
- Progress towards https://github.com/bevyengine/bevy/issues/5178

## Solution

- Upgrade to gltf-rs 1.3 supporiting
[KHR_materials_emissive_strength](https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Khronos/KHR_materials_emissive_strength/README.md)

---

## Changelog

- GLTF files using `emissiveStrength` (such as those exported by
blender) are now supported

## Migration Guide

- The GLTF asset loader will now factor in `emissiveStrength` when
converting to Bevy's `StandardMaterial::emissive`. Blender will export
emissive materials using this field. Remove the field from your GLTF
files or manually modify your materials post-asset-load to match how
Bevy would load these files in previous versions.
2023-08-24 00:17:44 +00:00
Carter Anderson
7c3131a761
Bump Version after Release (#9106)
CI-capable version of #9086

---------

Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François <mockersf@gmail.com>
2023-07-10 21:19:27 +00:00
Carter Anderson
8ba9571eed
Release 0.11.0 (#9080)
I created this manually as Github didn't want to run CI for the
workflow-generated PR. I'm guessing we didn't hit this in previous
releases because we used bors.

Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
2023-07-09 08:43:47 +00:00