# Objective
- Improve antialiasing for non-point light shadow edges.
- Very partially addresses
https://github.com/bevyengine/bevy/issues/3628.
## Solution
- Implements "The Witness"'s shadow map sampling technique.
- Ported from @superdump's old branch, all credit to them :)
- Implements "Call of Duty: Advanced Warfare"'s stochastic shadow map
sampling technique when the velocity prepass is enabled, for use with
TAA.
- Uses interleaved gradient noise to generate a random angle, and then
averages 8 samples in a spiral pattern, rotated by the random angle.
- I also tried spatiotemporal blue noise, but it was far too noisy to be
filtered by TAA alone. In the future, we should try spatiotemporal blue
noise + a specialized shadow denoiser such as
https://gpuopen.com/fidelityfx-denoiser/#shadow. This approach would
also be useful for hybrid rasterized applications with raytraced
shadows.
- The COD presentation has an interesting temporal dithering of the
noise for use with temporal supersampling that we should revisit when we
get DLSS/FSR/other TSR.
---
## Changelog
* Added `ShadowFilteringMethod`. Improved directional light and
spotlight shadow edges to be less aliased.
## Migration Guide
* Shadows cast by directional lights or spotlights now have smoother
edges. To revert to the old behavior, add
`ShadowFilteringMethod::Hardware2x2` to your cameras.
---------
Co-authored-by: IceSentry <c.giguere42@gmail.com>
Co-authored-by: Daniel Chia <danstryder@gmail.com>
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Brandon Dyer <brandondyer64@gmail.com>
Co-authored-by: Edgar Geier <geieredgar@gmail.com>
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
# Objective
- After https://github.com/bevyengine/bevy/pull/9903, example
`mesh2d_manual` doesn't render anything
## Solution
- Fix the example using the new `RenderMesh2dInstances`
# Objective
- Fix TextureAtlasBuilder padding issue
TextureAtlasBuilder padding is reserved during add_texture() but can
still be changed afterwards. This means that changing padding after the
textures will be wrongly applied, either distorting the textures or
panicking if new padding is higher than texture+old padding.
## Solution
- Delay applying padding until finish()
# Objective
Allow Bevy apps to run without requiring to start from the main thread.
This allows other projects and applications to do things like spawning a
normal or scoped
thread and run Bevy applications there.
The current behaviour if you try this is a panic.
## Solution
Allow this by default on platforms winit supports this behaviour on
(x11, Wayland, Windows).
---
## Changelog
### Added
- Added the ability to start Bevy apps outside of the main thread on
x11, Wayland, Windows
---------
Signed-off-by: Torstein Grindvik <torstein.grindvik@nordicsemi.no>
Signed-off-by: Torstein Grindvik <torstein.grindvik@muybridge.com>
Co-authored-by: Torstein Grindvik <torstein.grindvik@muybridge.com>
Co-authored-by: James Liu <contact@jamessliu.com>
# Objective
- Fixes#8140
## Solution
- Added Explicit Error Typing for `AssetLoader` and `AssetSaver`, which
were the last instances of `anyhow` in use across Bevy.
---
## Changelog
- Added an associated type `Error` to `AssetLoader` and `AssetSaver` for
use with the `load` and `save` methods respectively.
- Changed `ErasedAssetLoader` and `ErasedAssetSaver` `load` and `save`
methods to use `Box<dyn Error + Send + Sync + 'static>` to allow for
arbitrary `Error` types from the non-erased trait variants. Note the
strict requirements match the pre-existing requirements around
`anyhow::Error`.
## Migration Guide
- `anyhow` is no longer exported by `bevy_asset`; Add it to your own
project (if required).
- `AssetLoader` and `AssetSaver` have an associated type `Error`; Define
an appropriate error type (e.g., using `thiserror`), or use a pre-made
error type (e.g., `anyhow::Error`). Note that using `anyhow::Error` is a
drop-in replacement.
- `AssetLoaderError` has been removed; Define a new error type, or use
an alternative (e.g., `anyhow::Error`)
- All the first-party `AssetLoader`'s and `AssetSaver`'s now return
relevant (and narrow) error types instead of a single ambiguous type;
Match over the specific error type, or encapsulate (`Box<dyn>`,
`thiserror`, `anyhow`, etc.)
## Notes
A simpler PR to resolve this issue would simply define a Bevy `Error`
type defined as `Box<dyn std::error::Error + Send + Sync + 'static>`,
but I think this type of error handling should be discouraged when
possible. Since only 2 traits required the use of `anyhow`, it isn't a
substantive body of work to solidify these error types, and remove
`anyhow` entirely. End users are still encouraged to use `anyhow` if
that is their preferred error handling style. Arguably, adding the
`Error` associated type gives more freedom to end-users to decide
whether they want more or less explicit error handling (`anyhow` vs
`thiserror`).
As an aside, I didn't perform any testing on Android or WASM. CI passed
locally, but there may be mistakes for those platforms I missed.
# Objective
assets v2 broke custom shader imports. fix them
## Solution
store handles of any file dependencies in the `Shader` to avoid them
being immediately dropped.
also added a use into the `shader_material` example so that it'll be
harder to break support in future.
# Objective
- Updates for rust 1.73
## Solution
- new doc check for `redundant_explicit_links`
- updated to text for compile fail tests
---
## Changelog
- updates for rust 1.73
# Objective
https://github.com/bevyengine/bevy/pull/7328 introduced an API to
override the global wireframe config. I believe it is flawed for a few
reasons.
This PR uses a non-breaking API. Instead of making the `Wireframe` an
enum I introduced the `NeverRenderWireframe` component. Here's the
reason why I think this is better:
- Easier to migrate since it doesn't change the old behaviour.
Essentially nothing to migrate. Right now this PR is a breaking change
but I don't think it has to be.
- It's similar to other "per mesh" rendering features like
NotShadowCaster/NotShadowReceiver
- It doesn't force new users to also think about global vs not global if
all they want is to render a wireframe
- This would also let you filter at the query definition level instead
of filtering when running the query
## Solution
- Introduce a `NeverRenderWireframe` component that ignores the global
config
---
## Changelog
- Added a `NeverRenderWireframe` component that ignores the global
`WireframeConfig`
# Objective
Add support for drawing outlines outside the borders of UI nodes.
## Solution
Add a new `Outline` component with `width`, `offset` and `color` fields.
Added `outline_width` and `outline_offset` fields to `Node`. This is set
after layout recomputation by the `resolve_outlines_system`.
Properties of outlines:
* Unlike borders, outlines have to be the same width on each edge.
* Outlines do not occupy any space in the layout.
* The `Outline` component won't be added to any of the UI node bundles,
it needs to be inserted separately.
* Outlines are drawn outside the node's border, so they are clipped
using the clipping rect of their entity's parent UI node (if it exists).
* `Val::Percent` outline widths are resolved based on the width of the
outlined UI node.
* The offset of the `Outline` adds space between an outline and the edge
of its node.
I was leaning towards adding an `outline` field to `Style` but a
separate component seems more efficient for queries and change
detection. The `Outline` component isn't added to bundles for the same
reason.
---
## Examples
* This image is from the `borders` example from the Bevy UI examples but
modified to include outlines. The UI nodes are the dark red rectangles,
the bright red rectangles are borders and the white lines offset from
each node are the outlines. The yellow rectangles are separate nodes
contained with the dark red nodes:
<img width="406" alt="outlines"
src="https://github.com/bevyengine/bevy/assets/27962798/4e6f315a-019f-42a4-94ee-cca8e684d64a">
* This is from the same example but using a branch that implements
border-radius. Here the the outlines are in orange and there is no
offset applied. I broke the borders implementation somehow during the
merge, which is why some of the borders from the first screenshot are
missing 😅. The outlines work nicely though (as long as you
can forgive the lack of anti-aliasing):
---
## Notes
As I explained above, I don't think the `Outline` component should be
added to UI node bundles. We can have helper functions though, perhaps
something as simple as:
```rust
impl NodeBundle {
pub fn with_outline(self, outline: Outline) -> (Self, Outline) {
(self, outline)
}
}
```
I didn't include anything like this as I wanted to keep the PR's scope
as narrow as possible. Maybe `with_outline` should be in a trait that we
implement for each UI node bundle.
---
## Changelog
Added support for outlines to Bevy UI.
* The `Outline` component adds an outline to a UI node.
* The `outline_width` field added to `Node` holds the resolved width of
the outline, which is set by the `resolve_outlines_system` after layout
recomputation.
* Outlines are drawn by the system `extract_uinode_outlines`.
# Objective
- When I've tested alternative async executors with bevy a common
problem is that they deadlock when we try to run nested scopes. i.e.
running a multithreaded schedule from inside another multithreaded
schedule. This adds a test to bevy_tasks for that so the issue can be
spotted earlier while developing.
## Changelog
- add a test for nested scopes.
# Objective
Fix warnings:
- #[warn(clippy::needless_pass_by_ref_mut)]
- #[warn(elided_lifetimes_in_associated_constant)]
## Solution
- Remove mut
- add &'static
## Errors
```rust
warning: this argument is a mutable reference, but not used mutably
--> crates/bevy_hierarchy/src/child_builder.rs:672:31
|
672 | fn assert_children(world: &mut World, parent: Entity, children: Option<&[Entity]>) {
| ^^^^^^^^^^ help: consider changing to: `&World`
|
= note: this is cfg-gated and may require further changes
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_pass_by_ref_mut
= note: `#[warn(clippy::needless_pass_by_ref_mut)]` on by default
```
```rust
warning: `&` without an explicit lifetime name cannot be used here
--> examples/shader/post_processing.rs:120:21
|
120 | pub const NAME: &str = "post_process";
| ^
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #115010 <https://github.com/rust-lang/rust/issues/115010>
= note: `#[warn(elided_lifetimes_in_associated_constant)]` on by default
help: use the `'static` lifetime
|
120 | pub const NAME: &'static str = "post_process";
| +++++++
```
# Objective
Allow the user to choose between "Add wireframes to these specific
entities" or "Add wireframes to everything _except_ these specific
entities".
Fixes#7309
# Solution
Make the `Wireframe` component act like an override to the global
configuration.
Having `global` set to `false`, and adding a `Wireframe` with `enable:
true` acts exactly as before.
But now the opposite is also possible: Set `global` to `true` and add a
`Wireframe` with `enable: false` will draw wireframes for everything
_except_ that entity.
Updated the example to show how overriding the global config works.
# Objective
- Fixes#9884
- Add API for ignoring ambiguities on certain resource or components.
## Solution
- Add a `IgnoreSchedulingAmbiguitiy` resource to the world which holds
the `ComponentIds` to be ignored
- Filter out ambiguities with those component id's.
## Changelog
- add `allow_ambiguous_component` and `allow_ambiguous_resource` apis
for ignoring ambiguities
---------
Co-authored-by: Ryan Johnson <ryanj00a@gmail.com>
# Objective
- Finish documenting `bevy_gltf`.
## Solution
- Document the remaining items, add links to the glTF spec where
relevant. Add the `warn(missing_doc)` attribute.
# Objective
- See fewer warnings when running `cargo clippy` locally.
## Solution
- allow `clippy::type_complexity` in more places, which also signals to
users they should do the same.
# Objective
`bevy_a11y` was impossible to integrate into some third-party projects
in part because it insisted on managing the accessibility tree on its
own.
## Solution
The changes in this PR were necessary to get `bevy_egui` working with
Bevy's AccessKit integration. They were tested on a fork of 0.11,
developed against `bevy_egui`, then ported to main and tested against
the `ui` example.
## Changelog
### Changed
* Add `bevy_a11y::ManageAccessibilityUpdates` to indicate whether the
ECS should manage accessibility tree updates.
* Add getter/setter to `bevy_a11y::AccessibilityRequested`.
* Add `bevy_a11y::AccessibilitySystem` `SystemSet` for ordering relative
to accessibility tree updates.
* Upgrade `accesskit` to v0.12.0.
### Fixed
* Correctly set initial accessibility focus to new windows on creation.
## Migration Guide
### Change direct accesses of `AccessibilityRequested` to use
`AccessibilityRequested.::get()`/`AccessibilityRequested::set()`
#### Before
```
use std::sync::atomic::Ordering;
// To access
accessibility_requested.load(Ordering::SeqCst)
// To update
accessibility_requested.store(true, Ordering::SeqCst);
```
#### After
```
// To access
accessibility_requested.get()
// To update
accessibility_requested.set(true);
```
---------
Co-authored-by: StaffEngineer <111751109+StaffEngineer@users.noreply.github.com>
Conventionally, the second UV map (`TEXCOORD1`, `UV1`) is used for
lightmap UVs. This commit allows Bevy to import them, so that a custom
shader that applies lightmaps can use those UVs if desired.
Note that this doesn't actually apply lightmaps to Bevy meshes; that
will be a followup. It does, however, open the door to future Bevy
plugins that implement baked global illumination.
## Changelog
### Added
The Bevy glTF loader now imports a second UV channel (`TEXCOORD1`,
`UV1`) from meshes if present. This can be used by custom shaders to
implement lightmapping.
# Objective
- Handle suspend / resume events on Android without exiting
## Solution
- On suspend: despawn the window, and set the control flow to wait for
events from the OS
- On resume: spawn a new window, and set the control flow to poll
In this video, you can see the Android example being suspended, stopping
receiving events, and working again after being resumed
https://github.com/bevyengine/bevy/assets/8672791/aaaf4b09-ee6a-4a0d-87ad-41f05def7945
Objective
---------
- Since #6742, It is not possible to build an `ArchetypeId` from a
`ArchetypeGeneration`
- This was useful to 3rd party crate extending the base bevy ECS
capabilities, such as [`bevy_ecs_dynamic`] and now
[`bevy_mod_dynamic_query`]
- Making `ArchetypeGeneration` opaque this way made it completely
useless, and removed the ability to limit archetype updates to a subset
of archetypes.
- Making the `index` method on `ArchetypeId` private prevented the use
of bitfields and other optimized data structure to store sets of
archetype ids. (without `transmute`)
This PR is not a simple reversal of the change. It exposes a different
API, rethought to keep the private stuff private and the public stuff
less error-prone.
- Add a `StartRange<ArchetypeGeneration>` `Index` implementation to
`Archetypes`
- Instead of converting the generation into an index, then creating a
ArchetypeId from that index, and indexing `Archetypes` with it, use
directly the old `ArchetypeGeneration` to get the range of new
archetypes.
From careful benchmarking, it seems to also be a performance improvement
(~0-5%) on add_archetypes.
---
Changelog
---------
- Added `impl Index<RangeFrom<ArchetypeGeneration>> for Archetypes` this
allows you to get a slice of newly added archetypes since the last
recorded generation.
- Added `ArchetypeId::index` and `ArchetypeId::new` methods. It should
enable 3rd party crates to use the `Archetypes` API in a meaningful way.
[`bevy_ecs_dynamic`]:
https://github.com/jakobhellermann/bevy_ecs_dynamic/tree/main
[`bevy_mod_dynamic_query`]:
https://github.com/nicopap/bevy_mod_dynamic_query/
---------
Co-authored-by: vero <email@atlasdostal.com>
# Objective
It is difficult to inspect the generated assembly of benchmark systems
using a tool such as `cargo-asm`
## Solution
Mark the related functions as `#[inline(never)]`. This way, you can pass
the module name as argument to `cargo-asm` to get the generated assembly
for the given function.
It may have as side effect to make benchmarks a bit more predictable and
useful too. As it prevents inlining where in bevy no inlining could
possibly take place.
### Measurements
Following the recommendations in
<https://easyperf.net/blog/2019/08/02/Perf-measurement-environment-on-Linux>,
I
1. Put my CPU in "AMD ECO" mode, which surprisingly is the equivalent of
disabling turboboost, giving more consistent performances
2. Disabled all hyperthreading cores using `echo 0 >
/sys/devices/system/cpu/cpu{11,12…}/online`
3. Set the scaling governor to `performance`
4. Manually disabled AMD boost with `echo 0 >
/sys/devices/system/cpu/cpufreq/boost`
5. Set the nice level of the criterion benchmark using `cargo bench … &
sudo renice -n -5 -p $! ; fg`
6. Not running any other program than the benchmarks (outside of system
daemons and the X11 server)
With this setup, running multiple times the same benchmarks on `main`
gives me a lot of "regression" and "improvement" messages, which is
absurd given that no code changed.
On this branch, there is still some spurious performance change
detection, but they are much less frequent.
This only accounts for `iter_simple` and `iter_frag` benchmarks of
course.
# Objective
We've done a lot of work to remove the pattern of a `&World` with
interior mutability (#6404, #8833). However, this pattern still persists
within `bevy_ecs` via the `unsafe_world` method.
## Solution
* Make `unsafe_world` private. Adjust any callsites to use
`UnsafeWorldCell` for interior mutability.
* Add `UnsafeWorldCell::removed_components`, since it is always safe to
access the removed components collection through `UnsafeWorldCell`.
## Future Work
Remove/hide `UnsafeWorldCell::world_metadata`, once we have provided
safe ways of accessing all world metadata.
---
## Changelog
+ Added `UnsafeWorldCell::removed_components`, which provides read-only
access to a world's collection of removed components.
# Objective
- Fixes#4610
## Solution
- Replaced all instances of `parking_lot` locks with equivalents from
`std::sync`. Acquiring locks within `std::sync` can fail, so
`.expect("Lock Poisoned")` statements were added where required.
## Comments
In [this
comment](https://github.com/bevyengine/bevy/issues/4610#issuecomment-1592407881),
the lack of deadlock detection was mentioned as a potential reason to
not make this change. From what I can gather, Bevy doesn't appear to be
using this functionality within the engine. Unless it was expected that
a Bevy consumer was expected to enable and use this functionality, it
appears to be a feature lost without consequence.
Unfortunately, `cpal` and `wgpu` both still rely on `parking_lot`,
leaving it in the dependency graph even after this change.
From my basic experimentation, this change doesn't appear to have any
performance impacts, positive or negative. I tested this using
`bevymark` with 50,000 entities and observed 20ms of frame-time before
and after the change. More extensive testing with larger/real projects
should probably be done.
# Objective
`Has<T>` was added to bevy_ecs, but we're still using the
`Option<With<T>>` pattern in multiple locations.
## Solution
Replace them with `Has<T>`.
# Objective
Add a new method so you can do `set_if_neq` with dereferencing
components: `as_deref_mut()`!
## Solution
Added an as_deref_mut method so that we can use `set_if_neq()` without
having to wrap up types for derefencable components
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Joseph <21144246+JoJoJet@users.noreply.github.com>
# Objective
- Fixes#9363
## Solution
Moved `fq_std` from `bevy_reflect_derive` to `bevy_macro_utils`. This
does make the `FQ*` types public where they were previously private,
which is a change to the public-facing API, but I don't believe a
breaking one. Additionally, I've done a basic QA pass over the
`bevy_macro_utils` crate, adding `deny(unsafe)`, `warn(missing_docs)`,
and documentation where required.
# Objective
Avert a panic when removing resources from Scenes.
### Reproduction Steps
```rust
let mut scene = Scene::new(World::default());
scene.world.init_resource::<Time>();
scene.world.remove_resource::<Time>();
scene.clone_with(&app.resource::<AppTypeRegistry>());
```
### Panic Message
```
thread 'Compute Task Pool (10)' panicked at 'Requested resource bevy_time::time::Time does not exist in the `World`.
Did you forget to add it using `app.insert_resource` / `app.init_resource`?
Resources are also implicitly added via `app.add_event`,
and can be added by plugins.', .../bevy/crates/bevy_ecs/src/reflect/resource.rs:203:52
```
## Solution
Check that the resource actually still exists before copying.
---
## Changelog
- resolved a panic caused by removing resources from scenes
# Objective
Finish documenting `bevy_scene`.
## Solution
Document the remaining items and add a crate-level `warn(missing_doc)`
attribute as for the other crates with completed documentation.
# Objective
`extract_meshes` can easily be one of the most expensive operations in
the blocking extract schedule for 3D apps. It also has no fundamentally
serialized parts and can easily be run across multiple threads. Let's
speed it up by parallelizing it!
## Solution
Use the `ThreadLocal<Cell<Vec<T>>>` approach utilized by #7348 in
conjunction with `Query::par_iter` to build a set of thread-local
queues, and collect them after going wide.
## Performance
Using `cargo run --profile stress-test --features trace_tracy --example
many_cubes`. Yellow is this PR. Red is main.
`extract_meshes`:
An average reduction from 1.2ms to 770us is seen, a 41.6% improvement.
Note: this is still not including #9950's changes, so this may actually
result in even faster speedups once that's merged in.
# Objective
- sometimes when bevy shuts down on certain machines the render thread
tries to send the time after the main world has been dropped.
- fixes an error mentioned in a reply in
https://github.com/bevyengine/bevy/issues/9543
---
## Changelog
- ignore disconnected errors from the time channel.
# Objective
The `States::variants` method was once used to construct `OnExit` and
`OnEnter` schedules for every possible value of a given `States` type.
[Since the switch to lazily initialized
schedules](https://github.com/bevyengine/bevy/pull/8028/files#diff-b2fba3a0c86e496085ce7f0e3f1de5960cb754c7d215ed0f087aa556e529f97f),
we no longer need to track every possible value.
This also opens the door to `States` types that aren't enums.
## Solution
- Remove the unused `States::variants` method and its associated type.
- Remove the enum-only restriction on derived States types.
---
## Changelog
- Removed `States::variants` and its associated type.
- Derived `States` can now be datatypes other than enums.
## Migration Guide
- `States::variants` no longer exists. If you relied on this function,
consider using a library that provides enum iterators.
# Objective
I was wondering whether to use `Timer::finished` or
`Timer::just_finished` for my repeating timer. This PR clarifies their
difference (or rather, lack thereof).
## Solution
More docs & examples.
# Objective
- There were a few typos in the project.
- This PR fixes these typos.
## Solution
- Fixing the typos.
Signed-off-by: SADIK KUZU <sadikkuzu@hotmail.com>
# Objective
In order to derive `Asset`s (v2), `TypePath` must also be implemented.
`TypePath` is not currently in the prelude, but given it is *required*
when deriving something that *is* in the prelude, I think it deserves to
be added.
## Solution
Add `TypePath` to `bevy_reflect::prelude`.
# Objective
Text bounds are computed by the layout algorithm using the text's
measurefunc so that text will only wrap after it's used the maximum
amount of available horizontal space.
When the layout size is returned the layout coordinates are rounded and
this sometimes results in the final size of the Node not matching the
size computed with the measurefunc. This means that the text may no
longer fit the horizontal available space and instead wrap onto a new
line. However, no glyphs will be generated for this new line because no
vertical space for the extra line was allocated.
fixes#9874
## Solution
Store both the rounded and unrounded node sizes in `Node`.
Rounding is used to eliminate pixel-wide gaps between nodes that should
be touching edge to edge, but this isn't necessary for text nodes as
they don't have solid edges.
## Changelog
* Added the `rounded_size: Vec2` field to `Node`.
* `text_system` uses the unrounded node size when computing a text
layout.
---------
Co-authored-by: Rob Parrett <robparrett@gmail.com>
# Objective
- run mobile tests on more devices / OS versions
## Solution
- Add more recent iOS devices / OS versions
- Add older Android devices / OS versions
You can check the results of a recent run on those devices here:
https://percy.io/dede4209/Bevy-Mobile-Example/builds/30355307
# Objective
Improve compatibility with macOS Sonoma and Xcode 15.0.
## Solution
- Adds the workaround by @ptxmac to ignore the invalid window sizes
provided by `winit` on macOS 14.0
- This still provides a slightly wrong content size when resizing (it
fails to account for the window title bar, so some content gets clipped
at the bottom) but it's _much better_ than crashing.
- Adds docs on how to work around the `bindgen` bug on Xcode 15.0.
## Related Issues:
- https://github.com/RustAudio/coreaudio-sys/issues/85
- https://github.com/rust-windowing/winit/issues/2876
---
## Changelog
- Added a workaround for a `winit`-related crash under macOS Sonoma
(14.0)
---------
Co-authored-by: Peter Kristensen <peter@ptx.dk>
# Objective
- Improve rendering performance, particularly by avoiding the large
system commands costs of using the ECS in the way that the render world
does.
## Solution
- Define `EntityHasher` that calculates a hash from the
`Entity.to_bits()` by `i | (i.wrapping_mul(0x517cc1b727220a95) << 32)`.
`0x517cc1b727220a95` is something like `u64::MAX / N` for N that gives a
value close to π and that works well for hashing. Thanks for @SkiFire13
for the suggestion and to @nicopap for alternative suggestions and
discussion. This approach comes from `rustc-hash` (a.k.a. `FxHasher`)
with some tweaks for the case of hashing an `Entity`. `FxHasher` and
`SeaHasher` were also tested but were significantly slower.
- Define `EntityHashMap` type that uses the `EntityHashser`
- Use `EntityHashMap<Entity, T>` for render world entity storage,
including:
- `RenderMaterialInstances` - contains the `AssetId<M>` of the material
associated with the entity. Also for 2D.
- `RenderMeshInstances` - contains mesh transforms, flags and properties
about mesh entities. Also for 2D.
- `SkinIndices` and `MorphIndices` - contains the skin and morph index
for an entity, respectively
- `ExtractedSprites`
- `ExtractedUiNodes`
## Benchmarks
All benchmarks have been conducted on an M1 Max connected to AC power.
The tests are run for 1500 frames. The 1000th frame is captured for
comparison to check for visual regressions. There were none.
### 2D Meshes
`bevymark --benchmark --waves 160 --per-wave 1000 --mode mesh2d`
#### `--ordered-z`
This test spawns the 2D meshes with z incrementing back to front, which
is the ideal arrangement allocation order as it matches the sorted
render order which means lookups have a high cache hit rate.
<img width="1112" alt="Screenshot 2023-09-27 at 07 50 45"
src="https://github.com/bevyengine/bevy/assets/302146/e140bc98-7091-4a3b-8ae1-ab75d16d2ccb">
-39.1% median frame time.
#### Random
This test spawns the 2D meshes with random z. This not only makes the
batching and transparent 2D pass lookups get a lot of cache misses, it
also currently means that the meshes are almost certain to not be
batchable.
<img width="1108" alt="Screenshot 2023-09-27 at 07 51 28"
src="https://github.com/bevyengine/bevy/assets/302146/29c2e813-645a-43ce-982a-55df4bf7d8c4">
-7.2% median frame time.
### 3D Meshes
`many_cubes --benchmark`
<img width="1112" alt="Screenshot 2023-09-27 at 07 51 57"
src="https://github.com/bevyengine/bevy/assets/302146/1a729673-3254-4e2a-9072-55e27c69f0fc">
-7.7% median frame time.
### Sprites
**NOTE: On `main` sprites are using `SparseSet<Entity, T>`!**
`bevymark --benchmark --waves 160 --per-wave 1000 --mode sprite`
#### `--ordered-z`
This test spawns the sprites with z incrementing back to front, which is
the ideal arrangement allocation order as it matches the sorted render
order which means lookups have a high cache hit rate.
<img width="1116" alt="Screenshot 2023-09-27 at 07 52 31"
src="https://github.com/bevyengine/bevy/assets/302146/bc8eab90-e375-4d31-b5cd-f55f6f59ab67">
+13.0% median frame time.
#### Random
This test spawns the sprites with random z. This makes the batching and
transparent 2D pass lookups get a lot of cache misses.
<img width="1109" alt="Screenshot 2023-09-27 at 07 53 01"
src="https://github.com/bevyengine/bevy/assets/302146/22073f5d-99a7-49b0-9584-d3ac3eac3033">
+0.6% median frame time.
### UI
**NOTE: On `main` UI is using `SparseSet<Entity, T>`!**
`many_buttons`
<img width="1111" alt="Screenshot 2023-09-27 at 07 53 26"
src="https://github.com/bevyengine/bevy/assets/302146/66afd56d-cbe4-49e7-8b64-2f28f6043d85">
+15.1% median frame time.
## Alternatives
- Cart originally suggested trying out `SparseSet<Entity, T>` and indeed
that is slightly faster under ideal conditions. However,
`PassHashMap<Entity, T>` has better worst case performance when data is
randomly distributed, rather than in sorted render order, and does not
have the worst case memory usage that `SparseSet`'s dense `Vec<usize>`
that maps from the `Entity` index to sparse index into `Vec<T>`. This
dense `Vec` has to be as large as the largest Entity index used with the
`SparseSet`.
- I also tested `PassHashMap<u32, T>`, intending to use `Entity.index()`
as the key, but this proved to sometimes be slower and mostly no
different.
- The only outstanding approach that has not been implemented and tested
is to _not_ clear the render world of its entities each frame. That has
its own problems, though they could perhaps be solved.
- Performance-wise, if the entities and their component data were not
cleared, then they would incur table moves on spawn, and should not
thereafter, rather just their component data would be overwritten.
Ideally we would have a neat way of either updating data in-place via
`&mut T` queries, or inserting components if not present. This would
likely be quite cumbersome to have to remember to do everywhere, but
perhaps it only needs to be done in the more performance-sensitive
systems.
- The main problem to solve however is that we want to both maintain a
mapping between main world entities and render world entities, be able
to run the render app and world in parallel with the main app and world
for pipelined rendering, and at the same time be able to spawn entities
in the render world in such a way that those Entity ids do not collide
with those spawned in the main world. This is potentially quite
solvable, but could well be a lot of ECS work to do it in a way that
makes sense.
---
## Changelog
- Changed: Component data for entities to be drawn are no longer stored
on entities in the render world. Instead, data is stored in a
`EntityHashMap<Entity, T>` in various resources. This brings significant
performance benefits due to the way the render app clears entities every
frame. Resources of most interest are `RenderMeshInstances` and
`RenderMaterialInstances`, and their 2D counterparts.
## Migration Guide
Previously the render app extracted mesh entities and their component
data from the main world and stored them as entities and components in
the render world. Now they are extracted into essentially
`EntityHashMap<Entity, T>` where `T` are structs containing an
appropriate group of data. This means that while extract set systems
will continue to run extract queries against the main world they will
store their data in hash maps. Also, systems in later sets will either
need to look up entities in the available resources such as
`RenderMeshInstances`, or maintain their own `EntityHashMap<Entity, T>`
for their own data.
Before:
```rust
fn queue_custom(
material_meshes: Query<(Entity, &MeshTransforms, &Handle<Mesh>), With<InstanceMaterialData>>,
) {
...
for (entity, mesh_transforms, mesh_handle) in &material_meshes {
...
}
}
```
After:
```rust
fn queue_custom(
render_mesh_instances: Res<RenderMeshInstances>,
instance_entities: Query<Entity, With<InstanceMaterialData>>,
) {
...
for entity in &instance_entities {
let Some(mesh_instance) = render_mesh_instances.get(&entity) else { continue; };
// The mesh handle in `AssetId<Mesh>` form, and the `MeshTransforms` can now
// be found in `mesh_instance` which is a `RenderMeshInstance`
...
}
}
```
---------
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
# Objective
Complete the documentation for `bevy_window`.
## Solution
The `warn(missing_doc)` attribute was only applying to the `cursor`
module as it was declared as an inner attribute. I switched it to an
outer attribute and documented the remaining items.
