# Objective
Document how to use Tracy memory profiling.
Fixes https://github.com/bevyengine/bevy/issues/8417.
## Solution
Expand Tracy documentation in profiling.md.
## Testing
New documentation tested manually; no code changes made.
# Objective
Add example of an enum Component to ecs_guide.
Fixes https://github.com/bevyengine/bevy/issues/11344.
## Solution
Extended ecs_guide "game" to include an enum tracking whether a player
is on a "hot" or "cold" streak.
## Testing
Ran example manually.
cc @MrGVSV
fixes#13944
I literally just added `Did you forget to call SystemState::apply?` to
the error message. I tested it with the code snipped from the Issue and
yeah it works
# Objective
Fixes#13982
## Solution
~~Adds a new field to `bevy_log::LogPlugin`: `ansi: bool`~~
Documents the use of `std::env::set_var("NO_COLOR", "1");` to disable
colour output in terminals.
## Testing
Yes, all tests passed when I ran `cargo run -p ci -- test` and `cargo
run -p ci -- lints`
I have only tested the code on my Mac, though I doubt this change would
have any affect on other platforms.
---
# Objective
Closes#5943. Seems like Assets v2 solved this one.
## Solution
Added a test to confirm that using `Reflect::clone_value` and then
`FromReflect::from_reflect` on a `Handle<T>` both increment the strong
count.
## Testing
A new test was added to confirm behavior.
---------
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
# Objective
Tight, in-frame generation, re-parenting, despawning, etc., UI
operations could sometime lead taffy to panic (invalid SlotMap key used)
when an entity with an invalid state later despawned.
Fixes#12403
## Solution
Move the `remove_entities` call after children updates.
## Testing
`sickle_ui` had a case that always caused the panic. Tested before this
change, after this change, and before the change again to make sure the
error is there without the fix. The fix worked. Test steps and used
commit described in issue #12403.
I have also ran every bevy UI example, though none of them deal with
entity re-parenting or removal. No regression detected on them.
Tested on Windows only.
Bumps [crate-ci/typos](https://github.com/crate-ci/typos) from 1.22.7 to
1.22.9.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/crate-ci/typos/releases">crate-ci/typos's
releases</a>.</em></p>
<blockquote>
<h2>v1.22.9</h2>
<h2>[1.22.9] - 2024-06-22</h2>
<h3>Fixes</h3>
<ul>
<li>Stop correcting <code>reoccurrence</code></li>
</ul>
<h2>v1.22.8</h2>
<h2>[1.22.8] - 2024-06-21</h2>
<h3>Features</h3>
<ul>
<li><em>(action)</em> Add Arm, Mac support</li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/crate-ci/typos/blob/master/CHANGELOG.md">crate-ci/typos's
changelog</a>.</em></p>
<blockquote>
<h2>[1.22.9] - 2024-06-22</h2>
<h3>Fixes</h3>
<ul>
<li>Stop correcting <code>reoccurrence</code></li>
</ul>
<h2>[1.22.8] - 2024-06-21</h2>
<h3>Features</h3>
<ul>
<li><em>(action)</em> Add Arm, Mac support</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="c16dc8f5b4"><code>c16dc8f</code></a>
chore: Release</li>
<li><a
href="c7ac1f9476"><code>c7ac1f9</code></a>
chore: Release</li>
<li><a
href="b34586cef4"><code>b34586c</code></a>
docs: Update changelog</li>
<li><a
href="ceaed5b649"><code>ceaed5b</code></a>
Merge pull request <a
href="https://redirect.github.com/crate-ci/typos/issues/1044">#1044</a>
from epage/reoccurrence</li>
<li><a
href="038802dc09"><code>038802d</code></a>
fix(dict): Don't correct reoccurrence</li>
<li><a
href="dde47868a5"><code>dde4786</code></a>
chore: Release</li>
<li><a
href="85d76b5b17"><code>85d76b5</code></a>
docs: Update changelog</li>
<li><a
href="ab67cbb949"><code>ab67cbb</code></a>
Merge pull request <a
href="https://redirect.github.com/crate-ci/typos/issues/1040">#1040</a>
from dyc3/action-support-mac-arm</li>
<li><a
href="89fad3115d"><code>89fad31</code></a>
feat[ci]: add support for mac and arm systems to the github action</li>
<li><a
href="ff7654294c"><code>ff76542</code></a>
chore(deps): Update Rust Stable to v1.79 (<a
href="https://redirect.github.com/crate-ci/typos/issues/1035">#1035</a>)</li>
<li>See full diff in <a
href="https://github.com/crate-ci/typos/compare/v1.22.7...v1.22.9">compare
view</a></li>
</ul>
</details>
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* Fixes https://github.com/bevyengine/bevy/issues/13813
* Fixes https://github.com/bevyengine/bevy/issues/13810
Tested a combined scene with both regular meshes and meshlet meshes
with:
* Regular forward setup
* Forward + normal/motion vector prepasses
* Deferred (with depth prepass since that's required)
* Deferred + depth/normal/motion vector prepasses
Still broken:
* Using meshlet meshes rendering in deferred and regular meshes
rendering in forward + depth/normal prepass. I don't know how to fix
this at the moment, so for now I've just add instructions to not mix
them.
# Objective
`with_event` will result in unsafe casting of event data of the given
type to the type expected by the Observer system. This is inherently
unsafe.
## Solution
Flag `Observer::with_event` and `ObserverDescriptor::with_events` as
unsafe. This will not affect normal workflows as `with_event` is
intended for very specific (largely internal) use cases.
This _should_ be backported to 0.14 before release.
---
## Changelog
- `Observer::with_event` is now unsafe.
- Rename `ObserverDescriptor::with_triggers` to
`ObserverDescriptor::with_events` and make it unsafe.
# Objective
- Fixes#13702
- When creating a new window, its scale was changed to match the one
returned by winit, but its size was not which resulted in an incorrect
size until the event with the correct size was received, at least 1
frame later
## Solution
- Apply the window scale to its size when creating it
I updated my 'main' branch, which accidentally closed the original PR
#13747. I'm reopening the this from an actual branch on my repo like I
should have done in the first place. Here's the original info from the
first PR:
* * *
# Problem
The `file_watcher` feature panics if the file_watcher's path "assets" is
not present. I stumbled upon this behavior when I was actually testing
against `embedded_watcher`. I had no "assets" directory and didn't need
one for [my project](https://github.com/shanecelis/bevy_plane_cut).
```text
$ cargo run --example simple; # Runs fine.
$ cargo run --example simple --feature embedded_watcher; # Panics
thread 'main' panicked at /Users/shane/.cargo/registry/src/index.crates.io-6f17d22bba15001f/bevy_asset-0.14.0-rc.2/src/io/source.rs:503:21:
Failed to create file watcher from path "assets", Error { kind: PathNotFound, paths: ["/Users/shane/Projects/bevy_plane_cut/assets"] }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
```
# Opinion
If a project runs without panicing, then adding the `file_watcher`
feature shouldn't cause it to panic.
# Suggested Solution
This PR suggests if the "assets" path does not exist, emit a warning
stating that the file watcher could not be created and why. All other
errors will be treated as before with a panic and a message.
```text
$ cargo run --example simple --feature embedded_watcher; # Panics
2024-06-08T08:55:11.385249Z WARN bevy_asset::io::source: Skip creating file watcher because path "assets" does not exist.
2024-06-08T08:55:11.385291Z WARN bevy_asset::io::source: AssetSourceId::Default does not have an AssetWatcher configured. Consider enabling the `file_watcher` feature.
```
The second warning is new and I'd prefer it didn't emit under this
condition, but I'll wait to see whether this is actually regarded as a
bug.
# Testing
No tests added. Compiled against my project and it demonstrated the
suggested behavior.
* * *
I changed the second warning to the following when the `file_watcher`
feature is present. When it's not present, it uses the same warning as
before.
```
024-06-09T01:22:16.880619Z WARN bevy_asset::io::source: Skip creating file watcher because path "assets" does not exist.
2024-06-09T01:22:16.880660Z WARN bevy_asset::io::source: AssetSourceId::Default does not have an AssetWatcher configured. Consider adding an "assets" directory.
```
# Objective
In a few examples, we're specifying a font or font size that is the same
as the current default value. Might as well use the default. That'll be
one less thing to worry about if we ever need to change the default font
size. (wink)
In a few others, we were using a value of `25.0` and it didn't seem like
it was different for an important reason, so I switched to the default
there too.
(There are a bunch of examples that use non-default font sizes for
various reasons. Not trying address them all here.)
# Objective
A couple issues with this example are evident from this screenshot of
the example showcase:
<img width="319" alt="image"
src="https://github.com/bevyengine/bevy/assets/200550/5325bb29-9576-4989-a5a3-a972c8bbf1af">
- The images are misaligned, closer to the right edge of the screen
- The example uses a custom window resolution with a different aspect
ratio from the default, which results in black bars
## Solution
- Use the default window size
- Adjust positions so that things are centered
This isn't really fixing a problem, but I also:
- Used the default font size and adjusted the text labels and gaps so
that everything still fits
Which is how I got here in the first place (one less font size to adjust
for the cosmic text PR).
## Before
<img width="1350" alt="Screenshot 2024-06-20 at 12 23 10 PM"
src="https://github.com/bevyengine/bevy/assets/200550/1c7cfcfe-7edc-4561-a4e7-9b3bc8f87f75">
## After
<img width="1280" alt="Screenshot 2024-06-20 at 12 23 30 PM"
src="https://github.com/bevyengine/bevy/assets/200550/abab8a46-4e11-4ee6-a407-ae3b8bf31975">
This is an attempt to address issue #13725, which was about the
geometric primitives in the bevy_math crate lacking some detail in the
docs.
# Objective
Fixes#13725
## Solution
Added details to the docstrings. Mostly this consisted of specifying
that the primitives are centered on the origin, or describing how
they're defined (e.g., a circle is the set of all points some distance
from the origin).
## Testing
No testing, since the only changes were to docs.
Fixes#13701
After `winit` upgrade to `0.31`, windows were no longer correctly
resizing. This appears to just have been a simple mistake, where the new
physical size was being sourced from the `winit` window rather than on
the incoming `Window` component.
## Testing
Tested on macOS, but I'm curious whether this was also broken on other
platforms.
# Objective
Fixes#13866
## Solution
Add `insert_before` in **FixedMainScheduleOrder** and
**MainScheduleOrder**, add `insert_startup_before` in
**MainScheduleOrder**, applying the same logic as `insert_after`, except
for parameters naming and insertion index.
This is a followup to https://github.com/bevyengine/bevy/pull/13904
based on the discussion there, and switches two HashMaps that used
meshlet ids as keys to Vec.
In addition to a small further performance boost for `from_mesh` (1.66s
=> 1.60s), this makes processing deterministic modulo threading issues
wrt CRT rand described in the linked PR. This is valuable for debugging,
as you can visually or programmatically inspect the meshlet distribution
before/after making changes that should not change the output, whereas
previously every asset rebuild would change the meshlet structure.
Tested with https://github.com/bevyengine/bevy/pull/13431; after this
change, the visual output of meshlets is consistent between asset
rebuilds, and the MD5 of the output GLB file does not change either,
which was not the case before.
# Objective
- Make primitive meshing behavior consisten across platforms
- Avoid using sizes bigger than `u32` since these aren't even supported
for meshes
## Solution
- Use `u32` instead of `usize` for resolution/subdivisions/segments/etc
fields
---
## Changelog
- Change resolutions in primitive mesh builders from `usize` to `u32`
## Migration Guide
- All primitive mesh builders now take `u32` instead of `usize` for
their resolution/subdivision/segment counts
# Objective
The documentation for
[`Transform::align`](https://docs.rs/bevy/0.14.0-rc.3/bevy/transform/components/struct.Transform.html#method.align)
mentions a hypothetical ship model. Showing this concretely would be a
nice improvement over using a cube.
> For example, if a spaceship model has its nose pointing in the
X-direction in its own local coordinates and its dorsal fin pointing in
the Y-direction, then align(Dir3::X, v, Dir3::Y, w) will make the
spaceship’s nose point in the direction of v, while the dorsal fin does
its best to point in the direction w.
## Solution
This commit makes the ship less hypothetical by using a kenney ship
model in the example.
The local axes for the ship needed to change to accommodate the gltf, so
the hypothetical in the documentation and this example's local axes
don't necessarily match. Docs use `align(Dir3::X, v, Dir3::Y, w)` and
this example now uses `(Vec3::NEG_Z, *first, Vec3::X, *second)`.
I manually modified the `craft_speederD` Node's `translation` to be
0,0,0 in the gltf file, which means it now differs from kenney's
original model.
Original ship from: https://kenney.nl/assets/space-kit
## Testing
```
cargo run --example align
```
# Objective
Fixes#13920
## Solution
As described in the issue.
## Testing
Moved a custom transition plugin in example before any of the app-state
methods.
# Objective
Fixes#13933.
## Solution
Changed the return type.
## Testing
Fixed and reused the pre-existing tests for `inspect_entity`.
---
## Migration Guide
- `World::inspect_entity` now returns an `Iterator` instead of a `Vec`.
If you need a `Vec`, immediately collect the iterator:
`world.inspect_entity(entity).collect<Vec<_>>()`
# Objective
Fixes#13845
## Solution
Fix inline docs links inside `init_state` and `insert_state`.
## Testing
- Did you test these changes? If so, how?
Manually checked on `cargo doc` and `rust-analyzer lsp`.
# Objective
Fix a 9-slice asymmetric border issue that
[QueenOfSquiggles](https://blobfox.coffee/@queenofsquiggles/112639035165575222)
found. Here's the behavior before:
<img width="340" alt="the-bug"
src="https://github.com/bevyengine/bevy/assets/54390/81ff1847-b2ea-4578-9fd0-af6ee96c5438">
## Solution
Here's the behavior with the fix.
<img width="327" alt="the-fix"
src="https://github.com/bevyengine/bevy/assets/54390/33a4e3f0-b6a8-448e-9654-1197218ea11d">
## Testing
I used QueenOfSquiggles
[repo](https://github.com/QueenOfSquiggles/my-bevy-learning-project) to
exercise the code. I manually went through a number of variations of the
border and caught a few other issues after the first pass. I added some
code to create random borders and though they often looked funny there
weren't any gaps like before.
### Unit Tests
I did add some tests to `slicer.rs` mostly as an exploratory programming
exercise. So they currently act as a limited, incomplete,
"golden-file"-ish approach. Perhaps they're not worth keeping.
In order to write the tests, I did add a `PartialEq` derive for
`TextureSlice`.
I only tested these changes on macOS.
---
## Changelog
Make 9-slice textures work with asymmetric borders.
# Objective
- Make gizmos behavior consistent across platforms
## Solution
- Use `u32` instead of `usize` for resolution/subdivisions/segments/etc
fields
---
## Changelog
- Change resolutions in gizmos from `usize` to `u32`
## Migration Guide
- All gizmos now take `u32` instead of `usize` for their
resolution/subdivision/segment counts
# Objective
- Primitives should not use poorly defined types like `usize`,
especially since they are serializable
## Solution
- Use `u32` instead of `usize`
- The generic array types do not need to be changed because this size is
not actually stored or serialized anywhere
---
## Migration Guide
- `RegularPolygon` now uses `u32` instead of `usize` for the number of
sides
# Objective
This PR aims to improve error handling for log filters.
Closes#13850
## Solution
I changed the parsing of LogPlugin its filter to lossy, so that it
prints the directives with an error but does not skip them. I decided on
letting it gracefully handle the error instead of panicking to be
consistent with the parsing from an environment variable that it tries
to do before parsing it from the LogPlugin filter.
If the user decides to specify the filter by an environment variable, it
would silently fail and default to the LogPlugin filter value. It now
prints an error before defaulting to the LogPlugin filter value.
Unfortunately, I could not try and loosely set the filter from the
environment variable because the `tracing-subscriber` module does not
expose the function it uses to get the environment variable, and I would
rather not copy its code. We may want to check if the maintainers are
open to exposing the method.
## Testing
Consider the following bevy app, where the second of the 3 filters is
invalid:
```
use bevy::{log::LogPlugin, prelude::*};
fn main() {
App::new().add_plugins(DefaultPlugins
.set(LogPlugin {
filter: "wgpu=error,my_package=invalid_log_level,naga=warn".into(),
..default()
})
).run();
}
```
In the previous situation, it would panic with a non-descriptive error:
"called `Result::unwrap()` on an `Err` value: ParseError { kind:
Other(None) }", while only 1 of the 3 filters is invalid. When running
`cargo run`, it will now use the two valid filters and print an error on
the invalid filter.
> ignoring `my_package=invalid_log_level`: invalid filter directive
This error comes from `tracing-subscriber` and cannot be altered as far
as I can see.
To test setting the log filter through an environment variable, you can
use `RUST_LOG="wgpu=error,my_package=invalid_log_level,naga=warn" cargo
run` to run your app. In the previous situation it would silently fail
and use the LogPlugin filter. It will now print an error before using
the LogPlugin filter.
> LogPlugin failed to parse filter from env: invalid filter directive
## Changelog
- Added warning when using invalid filter in the RUST_LOG environment
variable
- Prevent the app from panicking when setting an invalid LogPlugin
filter
---------
Co-authored-by: Luc Drenth <luc.drenth@ing.com>
# Objective
Add extra metadata for the shader examples that contains the location of
their associated shader file(s). This is to be used for the bevy website
shader examples so that the shader code is underneath the rust code.
## Solution
Parse the example rust files for mentions of `.wgsl`, `.frag`, and
`.vert`, then append the found paths to a field called
`shader_code_paths` in the generated `index.md`s for each shader
example.
# Objective
Fixes#13917
## Solution
Changed `IntoSystemSetConfigs::chain_ignore_deferred`'s return type from
`SystemConfigs` to `SystemSetConfigs`
## Testing
Tried to run the `ecs_guide` example, where `chain` method is replaced
by `chain_ignore_deferred` method
---
# Objective
- Fix a typo in documentation for `Query::single_mut`
## Solution
- Change `item` to `items`
## Testing
- I built the documentation and it looked fine.
- Since this only affects a doc comment, no further testing should be
necessary.
---
## Changelog
> This section is optional. If this was a trivial fix, or has no
externally-visible impact, you can delete this section.
- Fixed a typo in the documentation for Query.
# Objective
[`StableInterpolate`](https://dev-docs.bevyengine.org/bevy/math/trait.StableInterpolate.html)
was introduced after this example was written (or more accurately, the
two PRs were merged on the same day and developed in parallel).
The example used `Vec3::lerp` where I believe it is now preferred to use
`smooth_nudge`.
## Solution
Its not entirely clear to me whether `StableInterpolate` should be
preferred in this scenario, although it seems likely. So I figured a PR
to make the change would either result in it being merged or denied with
a reason.
## Testing
```
cargo run --example 2d_top_down_camera
```
Co-authored-by: François Mockers <mockersf@gmail.com>
# Objective
- Fixes#11933.
- Related: #12280.
## Solution
- Specify that, after applying `AmbientLight`, the resulting units are
in cd/m^2.
- This is based on [@fintelia's
comment](https://github.com/bevyengine/bevy/issues/11933#issuecomment-1995427587),
and will need to be verified.
---
## Changelog
- Specified units for `AmbientLight`'s `brightness` field.
This change reworks `find_connected_meshlets` to scale more linearly
with the mesh size, which significantly reduces the cost of building
meshlet representations. As a small extra complexity reduction, it moves
`simplify_scale` call out of the loop so that it's called once (it only
depends on the vertex data => is safe to cache).
The new implementation of connectivity analysis builds edge=>meshlet
list data structure, which allows us to only iterate through
`tuple_combinations` of a (usually) small list. There is still some
redundancy as if two meshlets share two edges, they will be represented
in the meshlet lists twice, but it's overall much faster.
Since the hash traversal is non-deterministic, to keep this part of the
algorithm deterministic for reproducible results we sort the output
adjacency lists.
Overall this reduces the time to process bunny mesh from ~4.2s to ~1.7s
when using release; in unoptimized builds the delta is even more
significant.
This was tested by using https://github.com/bevyengine/bevy/pull/13431
and:
a) comparing the result of `find_connected_meshlets` using old and new
code; they are equal in all steps of the clustering process
b) comparing the rendered result of the old code vs new code *after*
making the rest of the algorithm deterministic: right now the loop that
iterates through the result of `group_meshlets()` call executes in
different order between program runs. This is orthogonal to this change
and can be fixed separately.
Note: a future change can shrink the processing time further from ~1.7s
to ~0.4s with a small diff but that requires an update to meshopt crate
which is pending in https://github.com/gwihlidal/meshopt-rs/pull/42.
This change is independent.
# Objective
- first part of #13900
## Solution
- split `check_light_mesh_visibility `into
`check_dir_light_mesh_visibility `and
`check_point_light_mesh_visibility` for better review
# Objective
- After #12582 , Bevy split visibleEntities into a TypeIdMap for
different types of entities, but the behavior in
`check_light_mesh_visibility `simply calls HashMap::clear(), which will
reallocate memory every frame.
## Testing
cargo run --release --example many_cubes --features bevy/trace_tracy --
--shadows
~10% win in `check_light_mesh_visibilty`
# Objective
The error messages that appear when a value cannot be serialized or
deserialized via reflection could be slightly improved.
When one of these operations fails, some users are confused about how to
resolve the issue. I've spoken with a few who didn't know they could
register `ReflectSerialize` themselves. We should try to clarify this to
some degree in the error messages.
## Solution
Add some more detail to the error messages.
For example, replacing this:
```
Type 'core::ops::RangeInclusive<f32>' did not register ReflectSerialize
```
with this:
```
Type `core::ops::RangeInclusive<f32>` did not register the `ReflectSerialize` type data. For certain types, this may need to be registered manually using `register_type_data`
```
I also added a separate error message if the type was not registered in
the type registry at all:
```
Type `core::ops::RangeInclusive<f32>` is not registered in the type registry
```
## Testing
You can test locally by running:
```
cargo test --package bevy_reflect
```
---
## Changelog
- Added error message for missing type registration when serializing
reflect data
- Changed error message for missing `ReflectSerialize` registration when
serializing reflect data
- Changed error message for missing `ReflectDeserialize` registration
when deserializing reflect data
# Objective
I got little confused by the document of `all_tuples!` because type
names of the parameter `T` and extracted names `Pn` are difference.
## Solution
I fixed type names of the document.
# Objective
A very common way to organize a first-person view is to split it into
two kinds of models:
- The *view model* is the model that represents the player's body.
- The *world model* is everything else.
The reason for this distinction is that these two models should be
rendered with different FOVs.
The view model is typically designed and animated with a very specific
FOV in mind, so it is
generally *fixed* and cannot be changed by a player. The world model, on
the other hand, should
be able to change its FOV to accommodate the player's preferences for
the following reasons:
- *Accessibility*: How prone is the player to motion sickness? A wider
FOV can help.
- *Tactical preference*: Does the player want to see more of the
battlefield?
Or have a more zoomed-in view for precision aiming?
- *Physical considerations*: How well does the in-game FOV match the
player's real-world FOV?
Are they sitting in front of a monitor or playing on a TV in the living
room? How big is the screen?
## Solution
I've added an example implementing the described setup as follows.
The `Player` is an entity holding two cameras, one for each model. The
view model camera has a fixed
FOV of 70 degrees, while the world model camera has a variable FOV that
can be changed by the player.
I use different `RenderLayers` to select what to render.
- The world model camera has no explicit `RenderLayers` component, so it
uses the layer 0.
All static objects in the scene are also on layer 0 for the same reason.
- The view model camera has a `RenderLayers` component with layer 1, so
it only renders objects
explicitly assigned to layer 1. The arm of the player is one such
object.
The order of the view model camera is additionally bumped to 1 to ensure
it renders on top of the world model.
- The light source in the scene must illuminate both the view model and
the world model, so it is
assigned to both layers 0 and 1.
To better see the effect, the player can move the camera by dragging
their mouse and change the world model's FOV with the arrow keys. The
arrow up key maps to "decrease FOV" and the arrow down key maps to
"increase FOV". This sounds backwards on paper, but is more intuitive
when actually changing the FOV in-game since a decrease in FOV looks
like a zoom-in.
I intentionally do not allow changing the view model's FOV even though
it would be illustrative because that would be an anti-pattern and bloat
the code a bit.
The example is called `first_person_view_model` and not just
`first_person` because I want to highlight that this is not a simple
flycam, but actually renders the player.
## Testing
Default FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/8c2e804f-fac2-48c7-8a22-d85af999dfb2">
Decreased FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/1733b3e5-f583-4214-a454-3554e3cbd066">
Increased FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/0b0640e6-5743-46f6-a79a-7181ba9678e8">
Note that the white bar on the right represents the player's arm, which
is more obvious in-game because you can move the camera around.
The box on top is there to make sure that the view model is receiving
shadows.
I tested only on macOS.
---
## Changelog
I don't think new examples go in here, do they?
## Caveat
The solution used here was implemented with help by @robtfm on
[Discord](https://discord.com/channels/691052431525675048/866787577687310356/1241019224491561000):
> shadow maps are specific to lights, not to layers
> if you want shadows from some meshes that are not visible, you could
have light on layer 1+2, meshes on layer 2, camera on layer 1 (for
example)
> but this might change in future, it's not exactly an intended feature
In other words, the example code as-is is not guaranteed to work in the
future. I want to bring this up because the use-case presented here is
extremely common in first-person games and important for accessibility.
It would be good to have a blessed and easy way of how to achieve it.
I'm also not happy about how I get the `perspective` variable in
`change_fov`. Very open to suggestions :)
## Related issues
- Addresses parts of #12658
- Addresses parts of #12588
---------
Co-authored-by: Pascal Hertleif <killercup@gmail.com>
# Objective
While writing code for the `bevy_ecs` I noticed we were using a
unnecessarily stable sort to sort component ids
## Solution
- Sort component ids with a unstable sort
- Comb the bevy_ecs crate for any other obvious inefficiencies.
- Don't clone component vectors when inserting an archetype.
## Testing
I ran `cargo test -p bevy_ecs`. Everything else I leave to CI.
## Profiling
I measured about a 1% speed increase when spawning entities directly
into a world. Since the difference is so small (and might just be noise)
I didn't bother to figure out which of change if any made the biggest
difference.
<details>
<summary> Tracy data </summary>
Yellow is this PR. Red is the commit I branched from.
</details>
<details>
<summary>Methodology</summary>
I created a system that spawn a 1000 entities each with the same 30
components each frame, and then I measured it's run time. The unusually
high number of components was chosen because the standard library [will
use a insertion sort for slices under 20
elements](0de24a5177/library/core/src/slice/sort.rs (L1048-L1049)).
This holds for both stable and unstable sorts.
</details>
