# Objective
Hot reloading shader imports on windows is currently broken due to
inconsistent `/` and `\` usage ('/` is used in the user facing APIs and
`\` is produced by notify-rs (and likely other OS apis).
Fixes#10500
## Solution
Standardize import paths when loading a `Shader`. The correct long term
fix is to standardize AssetPath on `/`-only, but this is the right scope
of fix for a patch release.
---------
Co-authored-by: François <mockersf@gmail.com>
# Objective
Related to #10472.
Not having a hardcoded scale factor makes comparing results from these
stress tests difficult.
Contributors using high dpi screens may be rendering 4x as many pixels
as others (or more). Stress tests may have different behavior when moved
from one monitor in a dual setup to another. At very high resolutions,
different parts of the engine / hardware are being stressed.
1080p is also a far more common resolution for gaming.
## Solution
Use a consistent 1080p with `scale_factor_override: 1.0` everywhere.
In #9903, this sort of change was added specifically to `bevymark` and
`many_cubes` but it makes sense to do it everywhere.
## Discussion
- Maybe we should have a command line option, environment variable, or
`CI_TESTING_CONFIG` option for 1080p / 1440p / 4k.
- Will these look odd (small text?) when screenshotted and shown in the
example showcase? The aspect ratio is the same, but they will be
downscaled from 1080p instead of ~720p.
- Maybe there are other window properties that should be consistent
across stress tests. e.g. `resizable: false`.
- Should we add a `stress_test_window(title)` helper or something?
- Bevymark (pre-10472) was intentionally 800x600 to match "bunnymark", I
believe. I don't personally think this is very important.
# Objective
- `CommandQueue::apply` calculates the address of the end of the
internal buffer as a `usize` rather than as a pointer, requiring two
casts of `cursor` to `usize`. Casting pointers to integers is generally
discouraged and may also prevent optimizations. It's also unnecessary
here.
## Solution
- Calculate the end address as a pointer rather than a `usize`.
Small note:
A trivial translation of the old code to use pointers would have
computed `end_addr` as `cursor.add(self.bytes.len())`, which is not
wrong but is an additional `unsafe` operation that also needs to be
properly documented and proven correct. However this operation is
already implemented in the form of the safe `as_mut_ptr_range`, so I
just used that.
# Objective
- The docs on `AssetPath::try_parse` say that it will return an error
when the string is malformed, but it actually just `.unwrap()`s the
result.
## Solution
- Use `?` instead of unwrapping the result.
# Objective
Calling `RenderDevice::poll` requires an instance of `wgpu::Maintain`,
but the type was not reexported by bevy. Working around it requires
adding a dependency on `wgpu`, since bevy does not reexport the `wgpu`
crate as a whole anywhere.
## Solution
Reexport `wgpu::Maintain` in `render_resource`, where the other wgpu
types are reexported.
# Objective
There is an if statement checking if a node is present in a graph
moments after it explicitly being added.
Unless the edge function has super weird side effects and the tests
don't pass, this is unnecessary.
## Solution
Removed it
# Objective
- Allow registration of one-shot systems when those systems have already
been `Box`ed.
- Needed for `bevy_eventlisteners` which allows adding event listeners
with callbacks in normal systems. The current one shot system
implementation requires systems be registered from an exclusive system,
and that those systems be passed in as types that implement
`IntoSystem`. However, the eventlistener callback crate allows users to
define their callbacks in normal systems, by boxing the system and
deferring initialization to an exclusive system.
## Solution
- Separate the registration of the system from the boxing of the system.
This is non-breaking, and adds a new method.
---
## Changelog
- Added `World::register_boxed_system` to allow registration of
already-boxed one shot systems.
When `cargo doc -Zunstable-options -Zrustdoc-scrape-examples` (trying to
figure out why it doesn't work with bevy), I had the following warnings:
```
warning: unresolved link to `Quad`
--> examples/2d/mesh2d.rs:1:66
|
1 | //! Shows how to render a polygonal [`Mesh`], generated from a [`Quad`] primitive, in a 2D scene.
| ^^^^ no item named `Quad` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "mesh2d") generated 1 warning
warning: unresolved link to `update_weights`
--> examples/animation/morph_targets.rs:6:17
|
6 | //! See the [`update_weights`] system for details.
| ^^^^^^^^^^^^^^ no item named `update_weights` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: public documentation for `morph_targets` links to private item `name_morphs`
--> examples/animation/morph_targets.rs:7:43
|
7 | //! - How to read morph target names in [`name_morphs`].
| ^^^^^^^^^^^ this item is private
|
= note: this link will resolve properly if you pass `--document-private-items`
= note: `#[warn(rustdoc::private_intra_doc_links)]` on by default
warning: public documentation for `morph_targets` links to private item `setup_animations`
--> examples/animation/morph_targets.rs:8:48
|
8 | //! - How to play morph target animations in [`setup_animations`].
| ^^^^^^^^^^^^^^^^ this item is private
|
= note: this link will resolve properly if you pass `--document-private-items`
warning: `bevy` (example "morph_targets") generated 3 warnings
warning: unresolved link to `Quad`
--> examples/2d/mesh2d_vertex_color_texture.rs:1:66
|
1 | //! Shows how to render a polygonal [`Mesh`], generated from a [`Quad`] primitive, in a 2D scene.
| ^^^^ no item named `Quad` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "mesh2d_vertex_color_texture") generated 1 warning
warning: unresolved link to `UIScale`
--> examples/ui/ui_scaling.rs:1:36
|
1 | //! This example illustrates the [`UIScale`] resource from `bevy_ui`.
| ^^^^^^^ no item named `UIScale` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "ui_scaling") generated 1 warning
warning: unresolved link to `dependencies`
--> examples/app/headless.rs:5:6
|
5 | //! [dependencies]
| ^^^^^^^^^^^^ no item named `dependencies` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "headless") generated 1 warning
warning: unresolved link to `Material2d`
--> examples/2d/mesh2d_manual.rs:3:26
|
3 | //! It doesn't use the [`Material2d`] abstraction, but changes the vertex buffer to include verte...
| ^^^^^^^^^^ no item named `Material2d` in scope
|
= help: to escape `[` and `]` characters, add '\' before them like `\[` or `\]`
= note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
warning: `bevy` (example "mesh2d_manual") generated 1 warning
```
# Objective
Had an issue where I had `VisibilityBundle` inside a bundle that
implements `Clone`, but since `VisibilityBundle` doesn't implement
`Clone` that wasn't possible. This PR fixes that.
## Solution
Implement `Clone` for `VisibilityBundle` by deriving it. And also
`SpatialBundle` too because why not.
---
## Changelog
- Added implementation for `Clone` on `VisibilityBundle` and
`SpatialBundle`.
# Objective
Fix a shader error that happens when using pbr morph targets.
## Solution
Fix the function name in the `prepass.wgsl` shader, which is incorrectly
prefixed with `morph::` (added in
61bad4eb57 (diff-97e4500f0a36bc6206d7b1490c8dd1a69459ee39dc6822eb9b2f7b160865f49fR42)).
This section of the shader is only enabled when using morph targets, so
it seems like there are no tests / examples using it?
# Objective
- Entities with both a `BackgroundColor` and a
`Handle<CustomUiMaterial>` are extracted by both pipelines and results
in entities being overwritten in the render world
- Fixes#10431
## Solution
- Ignore entities with `BackgroundColor` when extracting ui material
entities, and document that limit
# Objective
- There is a specialized hasher for entities:
[`EntityHashMap`](https://docs.rs/bevy/latest/bevy/utils/type.EntityHashMap.html)
- [`EntityMapper`] currently uses a normal `HashMap<Entity, Entity>`
- Fixes#10391
## Solution
- Replace the normal `HashMap` with the more performant `EntityHashMap`
## Questions
- This does change public API. Should a system be implemented to help
migrate code?
- Perhaps an `impl From<HashMap<K, V, S>> for EntityHashMap<K, V>`
- I updated to docs for each function that I changed, but I may have
missed something
---
## Changelog
- Changed `EntityMapper` to use `EntityHashMap` instead of normal
`HashMap`
## Migration Guide
If you are using the following types, update their listed methods to use
the new `EntityHashMap`. `EntityHashMap` has the same methods as the
normal `HashMap`, so you just need to replace the name.
### `EntityMapper`
- `get_map`
- `get_mut_map`
- `new`
- `world_scope`
### `ReflectMapEntities`
- `map_all_entities`
- `map_entities`
- `write_to_world`
### `InstanceInfo`
- `entity_map`
- This is a property, not a method.
---
This is my first time contributing in a while, and I'm not familiar with
the usage of `EntityMapper`. I changed the type definition and fixed all
errors, but there may have been things I've missed. Please keep an eye
out for me!
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>
# Objective
- Fixes#10209
- Assets should work in single threaded
## Solution
- In single threaded mode, don't use `async_fs` but fallback on
`std::fs` with a thin layer to mimic the async API
- file `file_asset.rs` is the async imps from `mod.rs`
- file `sync_file_asset.rs` is the same with `async_fs` APIs replaced by
`std::fs`
- which module is used depends on the `multi-threaded` feature
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Fixes a small typo in `bevy_window/src/window.rs`
## Solution
Change `Should be used instead 'scale_factor' when set.` to `Should be
used instead of 'scale_factor' when set.`
# Objective
- Adopt #10239 to get it in time for the release
- Fix accessibility on macOS and linux
## Solution
- call `on_event` from AcccessKit adapter on winit events
---------
Co-authored-by: Nolan Darilek <nolan@thewordnerd.info>
Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- Changes the default clear color to match the code block color on
Bevy's website.
## Solution
- Changed the clear color, updated text in examples to ensure adequate
contrast. Inconsistent usage of white text color set to use the default
color instead, which is already white.
- Additionally, updated the `3d_scene` example to make it look a bit
better, and use bevy's branding colors.
# Objective
Fixes https://github.com/bevyengine/bevy/issues/9077 (see this issue for
motivations)
## Solution
Implement 1 and 2 of the "How to fix it" section of
https://github.com/bevyengine/bevy/issues/9077
`update_directional_light_cascades` is split into
`clear_directional_light_cascades` and a generic
`build_directional_light_cascades`, to clear once and potentially insert
many times.
---
## Changelog
`DirectionalLight`'s computation is now generic over `CameraProjection`
and can work with custom camera projections.
## Migration Guide
If you have a component `MyCustomProjection` that implements
`CameraProjection`:
- You need to implement a new required associated method,
`get_frustum_corners`, returning an array of the corners of a subset of
the frustum with given `z_near` and `z_far`, in local camera space.
- You can now add the
`build_directional_light_cascades::<MyCustomProjection>` system in
`SimulationLightSystems::UpdateDirectionalLightCascades` after
`clear_directional_light_cascades` for your projection to work with
directional lights.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Bevy's default bias values for directional and spot lights currently
cause significant artifacts. We should fix that so shadows look good by
default!
This is a less controversial/invasive alternative to #10188, which might
enable us to keep the default bias value low, but also has its own sets
of concerns and caveats that make it a risky choice for Bevy 0.12.
## Solution
Bump the default normal bias from `0.6` to `1.8`. There is precedent for
values in this general area as Godot has a default normal bias of `2.0`.
### Before
### After
## Migration Guide
The default `shadow_normal_bias` value for `DirectionalLight` and
`SpotLight` has changed to accommodate artifacts introduced with the new
shadow PCF changes. It is unlikely (especially given the new PCF shadow
behaviors with these values), but you might need to manually tweak this
value if your scene requires a lower bias and it relied on the previous
default value.
# Objective
Reimplement #8793 on top of the recent rendering changes.
## Solution
The batch creation logic is quite convoluted, but I tested it on enough
examples to convince myself that it works.
The initial value of `batch_image_handle` is changed from
`HandleId::Id(Uuid::nil(), u64::MAX)` to `DEFAULT_IMAGE_HANDLE.id()`,
which allowed me to make the if-block simpler I think.
The default image from `DEFAULT_IMAGE_HANDLE` is always inserted into
`UiImageBindGroups` even if it's not used. I tried to add a check so
that it would be only inserted when there is only one batch using the
default image but this crashed.
---
## Changelog
`prepare_uinodes`
* Changed the initial value of `batch_image_handle` to
`DEFAULT_IMAGE_HANDLE.id()`.
* The default image is added to the UI image bind groups before
assembling the batches.
* A new `UiBatch` isn't created when the next `ExtractedUiNode`s image
is set to `DEFAULT_IMAGE_HANDLE` (unless it is the first item in the UI
phase items list).
# Objective
fix crash / misbehaviour when `DeferredPrepass` is used without
`DepthPrepass`.
- Deferred lighting requires the depth prepass texture to be present, so
that the depth texture is available for binding. without it the deferred
lighting pass will use 0 for depth of all meshes.
- When `DeferredPrepass` is used without other prepass markers, and with
any materials that use `OpaqueRenderMode::Forward`, those entities will
try to queue to the `Opaque3dPrepass` render phase, which doesn't exist,
causing a crash.
## Solution
- check if the prepass phases exist before queueing
- generate prepass textures if `Opaque3dDeferred` is present
- add a note to the DeferredPrepass marker to note that DepthPrepass is
also required by the default deferred lighting pass
- also changed some `With<T>.is_some()`s to `Has<T>`s
# Objective
I was working with forward rendering prepass fragment shaders and ran
into an issue of not being able to access vertex colors in the prepass.
I was able to access vertex colors in regular fragment shaders as well
as in deferred shaders.
## Solution
It seems like this `if` was nested unintentionally as moving it outside
of the `deferred` block works.
---
## Changelog
Enable vertex colors in forward rendering prepass fragment shaders
# Objective
Alternative to #7310
## Solution
Implemented the suggestion from
https://github.com/bevyengine/bevy/pull/7310#discussion_r1083356655
I am guessing that these were originally split as an optimization, but I
am not sure since I believe the original author of the code is the one
speculating about combining them up there.
## Benchmarks
I ran three benchmarks to compare main, this PR, and the approach from
#7310
([updated](https://github.com/rparrett/bevy/commits/rebased-parallel-check-visibility)
to the same commit on main).
This seems to perform slightly better than main in scenarios where most
entities have AABBs, and a bit worse when they don't (`many_lights`).
That seems to make sense to me.
Either way, the difference is ~-20 microseconds in the more common
scenarios or ~+100 microseconds in the less common scenario. I would
speculate that this might perform **very slightly** worse in
single-threaded scenarios.
Benches were run in release mode for 2000 frames while capturing a trace
with tracy.
| bench | commit | check_visibility_system mean μs |
| -- | -- | -- |
| many_cubes | main | 929.5 |
| many_cubes | this | 914.0 |
| many_cubes | 7310 | 1003.5 |
| | |
| many_foxes | main | 191.6 |
| many_foxes | this | 173.2 |
| many_foxes | 7310 | 167.9 |
| | |
| many_lights | main | 619.3 |
| many_lights | this | 703.7 |
| many_lights | 7310 | 842.5 |
## Notes
Technically this behaves slightly differently -- prior to this PR, view
visibility was determined even for entities without `GlobalTransform`. I
don't think this has any practical impact though.
IMO, I don't think we need to do this. But I opened a PR because it
seemed like the handiest way to share the code / benchmarks.
## TODO
I have done some rudimentary testing with the examples above, but I can
do some screenshot diffing if it seems like we want to do this.
# Objective
- Revert #10296
## Solution
- Avoid implementing `Display` without a justification
- `Display` implementation is a guarantee without a direct use, takes
additional time to compile and require work to maintain
- `Debug`, `Reflect` or `Serialize` should cover all needs
# Objective
The `BuildWorldChildren` API was missing several methods that exist in
`BuildChildren`.
## Solution
Added the methods (and tests) for consistency.
# Objective
If we add the stack index to `Node` then we don't need to walk the
`UiStack` repeatedly during extraction.
## Solution
Add a field `stack_index` to `Node`.
Update it in `ui_stack_system`.
Iterate queries directly in the UI's extraction systems.
### Benchmarks
```
cargo run --profile stress-test --features trace_tracy --example many_buttons -- --no-text --no-borders
```
frames (yellow this PR, red main):
<img width="447" alt="frames-per-second"
src="https://github.com/bevyengine/bevy/assets/27962798/385c0ccf-c257-42a2-b736-117542d56eff">
`ui_stack_system`:
<img width="585" alt="ui-stack-system"
src="https://github.com/bevyengine/bevy/assets/27962798/2916cc44-2887-4c3b-a144-13250d84f7d5">
extract schedule:
<img width="469" alt="extract-schedule"
src="https://github.com/bevyengine/bevy/assets/27962798/858d4ab4-d99f-48e8-b153-1c92f51e0743">
---
## Changelog
* Added the field `stack_index` to `Node`.
* `ui_stack_system` updates `Node::stack_index` after a new `UiStack` is
generated.
* The UI's extraction functions iterate a query directly rather than
walking the `UiStack` and doing lookups.
# 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`
# Objective
- We need to check multiple times if a color is fully transparent, e.g.
for performance optimizations.
- Make code more readable.
- Reduce code duplication, to simplify making changes if needed (e.g. if
we need to take floating point weirdness into account later on).
## Solution
- Introduce a new `Color::is_fully_transparent` helper function to
determine if the alpha of a color is 0.
- Use the helper function in our UI rendering code.
---
## Changelog
- Added `Color::is_fully_transparent` helper function.
---------
Co-authored-by: François <mockersf@gmail.com>
# Objective
Right now, we flip the `world_normal` in response to `double_sided &&
!is_front`, however when calculating `N` from tangents and the normal
map, we don't flip the normal read from the normal map, which produces
extremely weird results.
## Solution
- Pass `double_sided` and `is_front` flags to the
`apply_normal_mapping()` function and use them to conditionally flip
`Nt`
## Comparison
Note: These are from a custom scene running with the `transmission`
branch, (#8015) I noticed lighting got pretty weird for the back side of
translucent `double_sided` materials whenever I added a normal map.
### Before
<img width="1392" alt="Screenshot 2023-10-31 at 01 26 06"
src="https://github.com/bevyengine/bevy/assets/418473/d5f8c9c3-aca1-4c2f-854d-f0d0fd2fb19a">
### After
<img width="1392" alt="Screenshot 2023-10-31 at 01 25 42"
src="https://github.com/bevyengine/bevy/assets/418473/fa0e1aa2-19ad-4c27-bb08-37299d97971c">
---
## Changelog
- Fixed a bug where `StandardMaterial::double_sided` would interact
incorrectly with normal maps, producing broken results.
# Objective
- Work towards GPU-driven culling
(https://github.com/bevyengine/bevy/pull/10164)
## Solution
- Pass the view frustum to the shader view uniform
---
## Changelog
- View Frustums are now extracted to the render world and made available
to shaders
# Objective
- Address inconsistent term usage in the docs for the alignment
properties for UI nodes. Fixes#10218
- `JustifyContent::Stretch` is missing despite being supported by Taffy,
being as the default value for Grids, so it should be added to Bevy as
well
## Solution
- Consistently provide links to the mdn site for the css equivalent
- Match (mostly) the documentation given on the pub struct and the
underlying enums
- Use the term `items` consistently to refer each child in the container
- Add `JustifyContent::Stretch` and map it to Taffy
## Migration Guide
- The `JustifyContents` enum has been expanded to include
`JustifyContents::Stretch`.
