# Objective
- Fixes#8074
- Adopts / Supersedes #8104
## Solution
Adapted from #8104 and affords the same benefits.
**Additions**
- [x] Update scrolling on relayout (height of node or contents may have
changed)
- [x] Make ScrollPosition component optional for ui nodes to avoid
checking every node on scroll
- [x] Nested scrollviews
**Omissions**
- Removed input handling for scrolling from `bevy_ui`. Users should
update `ScrollPosition` directly.
### Implementation
Adds a new `ScrollPosition` component. Updating this component on a
`Node` with an overflow axis set to `OverflowAxis::Scroll` will
reposition its children by that amount when calculating node transforms.
As before, no impact on the underlying Taffy layout.
Calculating this correctly is trickier than it was in #8104 due to
`"Update scrolling on relayout"`.
**Background**
When `ScrollPosition` is updated directly by the user, it can be
trivially handled in-engine by adding the parent's scroll position to
the final location of each child node. However, _other layout actions_
may result in a situation where `ScrollPosition` needs to be updated.
Consider a 1000 pixel tall vertically scrolling list of 100 elements,
each 100 pixels tall. Scrolled to the bottom, the
`ScrollPosition.offset_y` is 9000, just enough to display the last
element in the list. When removing an element from that list, the new
desired `ScrollPosition.offset_y` is 8900, but, critically, that is not
known until after the sizes and positions of the children of the
scrollable node are resolved.
All user scrolling code today handles this by delaying the resolution by
one frame. One notable disadvantage of this is the inability to support
`WinitSettings::desktop_app()`, since there would need to be an input
AFTER the layout change that caused the scroll position to update for
the results of the scroll position update to render visually.
I propose the alternative in this PR, which allows for same-frame
resolution of scrolling layout.
**Resolution**
_Edit: Below resolution is outdated, and replaced with the simpler usage
of taffy's `Layout::content_size`._
When recursively iterating the children of a node, each child now
returns a `Vec2` representing the location of their own bottom right
corner. Then, `[[0,0, [x,y]]` represents a bounding box containing the
scrollable area filled by that child. Scrollable parents aggregate those
areas into the bounding box of _all_ children, then consider that result
against `ScrollPosition` to ensure its validity.
In the event that resolution of the layout of the children invalidates
the `ScrollPosition` (e.g. scrolled further than there were children to
scroll to), _all_ children of that node must be recursively
repositioned. The position of each child must change as a result of the
change in scroll position.
Therefore, this implementation takes care to only spend the cost of the
"second layout pass" when a specific node actually had a
`ScrollPosition` forcibly updated by the layout of its children.
## Testing
Examples in `ui/scroll.rs`. There may be more complex node/style
interactions that were unconsidered.
---
## Showcase
![scroll](https://github.com/user-attachments/assets/1331138f-93aa-4a8f-959c-6be18a04ff03)
## Alternatives
- `bevy_ui` doesn't support scrolling.
- `bevy_ui` implements scrolling with a one-frame delay on reactions to
layout changes.
Currently, Bevy restricts animation clips to animating
`Transform::translation`, `Transform::rotation`, `Transform::scale`, or
`MorphWeights`, which correspond to the properties that glTF can
animate. This is insufficient for many use cases such as animating UI,
as the UI layout systems expect to have exclusive control over UI
elements' `Transform`s and therefore the `Style` properties must be
animated instead.
This commit fixes this, allowing for `AnimationClip`s to animate
arbitrary properties. The `Keyframes` structure has been turned into a
low-level trait that can be implemented to achieve arbitrary animation
behavior. Along with `Keyframes`, this patch adds a higher-level trait,
`AnimatableProperty`, that simplifies the task of animating single
interpolable properties. Built-in `Keyframes` implementations exist for
translation, rotation, scale, and morph weights. For the most part, you
can migrate by simply changing your code from
`Keyframes::Translation(...)` to `TranslationKeyframes(...)`, and
likewise for rotation, scale, and morph weights.
An example `AnimatableProperty` implementation for the font size of a
text section follows:
#[derive(Reflect)]
struct FontSizeProperty;
impl AnimatableProperty for FontSizeProperty {
type Component = Text;
type Property = f32;
fn get_mut(component: &mut Self::Component) -> Option<&mut
Self::Property> {
Some(&mut component.sections.get_mut(0)?.style.font_size)
}
}
In order to keep this patch relatively small, this patch doesn't include
an implementation of `AnimatableProperty` on top of the reflection
system. That can be a follow-up.
This patch builds on top of the new `EntityMutExcept<>` type in order to
widen the `AnimationTarget` query to include write access to all
components. Because `EntityMutExcept<>` has some performance overhead
over an explicit query, we continue to explicitly query `Transform` in
order to avoid regressing the performance of skeletal animation, such as
the `many_foxes` benchmark. I've measured the performance of that
benchmark and have found no significant regressions.
A new example, `animated_ui`, has been added. This example shows how to
use Bevy's built-in animation infrastructure to animate font size and
color, which wasn't possible before this patch.
## Showcase
https://github.com/user-attachments/assets/1fa73492-a9ce-405a-a8f2-4aacd7f6dc97
## Migration Guide
* Animation keyframes are now an extensible trait, not an enum. Replace
`Keyframes::Translation(...)`, `Keyframes::Scale(...)`,
`Keyframes::Rotation(...)`, and `Keyframes::Weights(...)` with
`Box::new(TranslationKeyframes(...))`, `Box::new(ScaleKeyframes(...))`,
`Box::new(RotationKeyframes(...))`, and
`Box::new(MorphWeightsKeyframes(...))` respectively.
# Objective
Fixes#15306
## Solution
- Add feature gate on the module and the place where each one is used
- Declare the features and make them default
## Testing
- CI
**Note:** This is an adoption of @Shfty 's adoption (#8131) of #3996!
All I've done is updated the branch and run the docs CI.
> **Note:** This is an adoption of #3996, originally authored by
@molikto
>
> # Objective
> Allow use of `wgpu::Features::SPIRV_SHADER_PASSTHROUGH` and the
corresponding `wgpu::Device::create_shader_module_spirv` for SPIR-V
shader assets.
>
> This enables use-cases where naga is not sufficient to load a given
(valid) SPIR-V module, i.e. cases where naga lacks support for a given
SPIR-V feature employed by a third-party codegen backend like
`rust-gpu`.
>
> ## Solution
> * Reimplemented the changes from [Spirv shader
bypass #3996](https://github.com/bevyengine/bevy/pull/3996), on account
of the original branch having been deleted.
> * Documented the new `spirv_shader_passthrough` feature flag with the
appropriate platform support context from [wgpu's
documentation](https://docs.rs/wgpu/latest/wgpu/struct.Features.html#associatedconstant.SPIRV_SHADER_PASSTHROUGH).
>
> ## Changelog
> * Adds a `spirv_shader_passthrough` feature flag to the following
crates:
>
> * `bevy`
> * `bevy_internal`
> * `bevy_render`
> * Extends `RenderDevice::create_shader_module` with a conditional call
to `wgpu::Device::create_shader_module_spirv` if
`spirv_shader_passthrough` is enabled and
`wgpu::Features::SPIRV_SHADER_PASSTHROUGH` is present for the current
platform.
> * Documents the relevant `wgpu` platform support in
`docs/cargo_features.md`
---------
Co-authored-by: Josh Palmer <1253239+Shfty@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Add examples for manipulating sprites and meshes by either mutating the
handle or direct manipulation of the asset, as described in #15056.
Closes#3130.
(The previous PR suffered a Git-tastrophe, and was unceremoniously
closed, sry! 😅 )
---------
Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
# Objective
> Rust 1.81 released the #[expect(...)] attribute, which works like
#[allow(...)] but throws a warning if the lint isn't raised. This is
preferred to #[allow(...)] because it tells us when it can be removed.
- Adopts the parts of #15118 that are complete, and updates the branch
so it can be merged.
- There were a few conflicts, let me know if I misjudged any of 'em.
Alice's
[recommendation](https://github.com/bevyengine/bevy/issues/15059#issuecomment-2349263900)
seems well-taken, let's do this crate by crate now that @BD103 has done
the lion's share of this!
(Relates to, but doesn't yet completely finish #15059.)
Crates this _doesn't_ cover:
- bevy_input
- bevy_gilrs
- bevy_window
- bevy_winit
- bevy_state
- bevy_render
- bevy_picking
- bevy_core_pipeline
- bevy_sprite
- bevy_text
- bevy_pbr
- bevy_ui
- bevy_gltf
- bevy_gizmos
- bevy_dev_tools
- bevy_internal
- bevy_dylib
---------
Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
Co-authored-by: Ben Frankel <ben.frankel7@gmail.com>
Co-authored-by: Antony <antony.m.3012@gmail.com>
[*Percentage-closer soft shadows*] are a technique from 2004 that allow
shadows to become blurrier farther from the objects that cast them. It
works by introducing a *blocker search* step that runs before the normal
shadow map sampling. The blocker search step detects the difference
between the depth of the fragment being rasterized and the depth of the
nearby samples in the depth buffer. Larger depth differences result in a
larger penumbra and therefore a blurrier shadow.
To enable PCSS, fill in the `soft_shadow_size` value in
`DirectionalLight`, `PointLight`, or `SpotLight`, as appropriate. This
shadow size value represents the size of the light and should be tuned
as appropriate for your scene. Higher values result in a wider penumbra
(i.e. blurrier shadows).
When using PCSS, temporal shadow maps
(`ShadowFilteringMethod::Temporal`) are recommended. If you don't use
`ShadowFilteringMethod::Temporal` and instead use
`ShadowFilteringMethod::Gaussian`, Bevy will use the same technique as
`Temporal`, but the result won't vary over time. This produces a rather
noisy result. Doing better would likely require downsampling the shadow
map, which would be complex and slower (and would require PR #13003 to
land first).
In addition to PCSS, this commit makes the near Z plane for the shadow
map configurable on a per-light basis. Previously, it had been hardcoded
to 0.1 meters. This change was necessary to make the point light shadow
map in the example look reasonable, as otherwise the shadows appeared
far too aliased.
A new example, `pcss`, has been added. It demonstrates the
percentage-closer soft shadow technique with directional lights, point
lights, spot lights, non-temporal operation, and temporal operation. The
assets are my original work.
Both temporal and non-temporal shadows are rather noisy in the example,
and, as mentioned before, this is unavoidable without downsampling the
depth buffer, which we can't do yet. Note also that the shadows don't
look particularly great for point lights; the example simply isn't an
ideal scene for them. Nevertheless, I felt that the benefits of the
ability to do a side-by-side comparison of directional and point lights
outweighed the unsightliness of the point light shadows in that example,
so I kept the point light feature in.
Fixes#3631.
[*Percentage-closer soft shadows*]:
https://developer.download.nvidia.com/shaderlibrary/docs/shadow_PCSS.pdf
## Changelog
### Added
* Percentage-closer soft shadows (PCSS) are now supported, allowing
shadows to become blurrier as they stretch away from objects. To use
them, set the `soft_shadow_size` field in `DirectionalLight`,
`PointLight`, or `SpotLight`, as applicable.
* The near Z value for shadow maps is now customizable via the
`shadow_map_near_z` field in `DirectionalLight`, `PointLight`, and
`SpotLight`.
## Screenshots
PCSS off:
![Screenshot 2024-05-24
120012](https://github.com/bevyengine/bevy/assets/157897/0d35fe98-245b-44fb-8a43-8d0272a73b86)
PCSS on:
![Screenshot 2024-05-24
115959](https://github.com/bevyengine/bevy/assets/157897/83397ef8-1317-49dd-bfb3-f8286d7610cd)
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
# Objective
Applies feedback from previous PR #15135 'cause it got caught up in the
merge train 🚂
I couldn't resist including roll, both for completeness and due to
playing too many games that implemented it as a child.
cc: @janhohenheim
# Objective
Add examples for zooming (and orbiting) orthographic and perspective
cameras.
I'm pretty green with 3D, so please treat with suspicion! I note that
if/when #15075 is merged, `.scale` will go away so this example uses
`.scaling_mode`.
Closes#2580
### Builder changes
- Increased meshlet max vertices/triangles from 64v/64t to 255v/128t
(meshoptimizer won't allow 256v sadly). This gives us a much greater
percentage of meshlets with max triangle count (128). Still not perfect,
we still end up with some tiny <=10 triangle meshlets that never really
get simplified, but it's progress.
- Removed the error target limit. Now we allow meshoptimizer to simplify
as much as possible. No reason to cap this out, as the cluster culling
code will choose a good LOD level anyways. Again leads to higher quality
LOD trees.
- After some discussion and consulting the Nanite slides again, changed
meshlet group error from _adding_ the max child's error to the group
error, to doing `group_error = max(group_error, max_child_error)`. Error
is already cumulative between LODs as the edges we're collapsing during
simplification get longer each time.
- Bumped the 65% simplification threshold to allow up to 95% of the
original geometry (e.g. accept simplification as valid even if we only
simplified 5% of the triangles). This gives us closer to
log2(initial_meshlet_count) LOD levels, and fewer meshlet roots in the
DAG.
Still more work to be done in the future here. Maybe trying METIS for
meshlet building instead of meshoptimizer.
Using ~8 clusters per group instead of ~4 might also make a big
difference. The Nanite slides say that they have 8-32 meshlets per
group, suggesting some kind of heuristic. Unfortunately meshopt's
compute_cluster_bounds won't work with large groups atm
(https://github.com/zeux/meshoptimizer/discussions/750#discussioncomment-10562641)
so hard to test.
Based on discussion from
https://github.com/bevyengine/bevy/discussions/14998,
https://github.com/zeux/meshoptimizer/discussions/750, and discord.
### Runtime changes
- cluster:triangle packed IDs are now stored 25:7 instead of 26:6 bits,
as max triangles per cluster are now 128 instead of 64
- Hardware raster now spawns 128 * 3 vertices instead of 64 * 3 vertices
to account for the new max triangles limit
- Hardware raster now outputs NaN triangles (0 / 0) instead of
zero-positioned triangles for extra vertex invocations over the cluster
triangle count. Shouldn't really be a difference idt, but I did it
anyways.
- Software raster now does 128 threads per workgroup instead of 64
threads. Each thread now loads, projects, and caches a vertex (vertices
0-127), and then if needed does so again (vertices 128-254). Each thread
then rasterizes one of 128 triangles.
- Fixed a bug with `needs_dispatch_remap`. I had the condition backwards
in my last PR, I probably committed it by accident after testing the
non-default code path on my GPU.
# Objective
Fixes#15032
## Solution
Reimplement support for the `flip_x` and `flip_y` fields.
This doesn't flip the border geometry, I'm not really sure whether that
is desirable or not.
Also fixes a bug that was causing the side and center slices to tile
incorrectly.
### Testing
```
cargo run --example ui_texture_slice_flip_and_tile
```
## Showcase
<img width="787" alt="nearest"
src="https://github.com/user-attachments/assets/bc044bae-1748-42ba-92b5-0500c87264f6">
With tiling need to use nearest filtering to avoid bleeding between the
slices.
---------
Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
This commit adds support for *masks* to the animation graph. A mask is a
set of animation targets (bones) that neither a node nor its descendants
are allowed to animate. Animation targets can be assigned one or more
*mask group*s, which are specific to a single graph. If a node masks out
any mask group that an animation target belongs to, animation curves for
that target will be ignored during evaluation.
The canonical use case for masks is to support characters holding
objects. Typically, character animations will contain hand animations in
the case that the character's hand is empty. (For example, running
animations may close a character's fingers into a fist.) However, when
the character is holding an object, the animation must be altered so
that the hand grips the object.
Bevy currently has no convenient way to handle this. The only workaround
that I can see is to have entirely separate animation clips for
characters' hands and bodies and keep them in sync, which is burdensome
and doesn't match artists' expectations from other engines, which all
effectively have support for masks. However, with mask group support,
this task is simple. We assign each hand to a mask group and parent all
character animations to a node. When a character grasps an object in
hand, we position the fingers as appropriate and then enable the mask
group for that hand in that node. This allows the character's animations
to run normally, while the object remains correctly attached to the
hand.
Note that even with this PR, we won't have support for running separate
animations for a character's hand and the rest of the character. This is
because we're missing additive blending: there's no way to combine the
two masked animations together properly. I intend that to be a follow-up
PR.
The major engines all have support for masks, though the workflow varies
from engine to engine:
* Unity has support for masks [essentially as implemented here], though
with layers instead of a tree. However, when using the Mecanim
("Humanoid") feature, precise control over bones is lost in favor of
predefined muscle groups.
* Unreal has a feature named [*layered blend per bone*]. This allows for
separate blend weights for different bones, effectively achieving masks.
I believe that the combination of blend nodes and masks make Bevy's
animation graph as expressible as that of Unreal, once we have support
for additive blending, though you may have to use more nodes than you
would in Unreal. Moreover, separating out the concepts of "blend weight"
and "which bones this node applies to" seems like a cleaner design than
what Unreal has.
* Godot's `AnimationTree` has the notion of [*blend filters*], which are
essentially the same as masks as implemented in this PR.
Additionally, this patch fixes a bug with weight evaluation whereby
weights weren't properly propagated down to grandchildren, because the
weight evaluation for a node only checked its parent's weight, not its
evaluated weight. I considered submitting this as a separate PR, but
given that this PR refactors that code entirely to support masks and
weights under a unified "evaluated node" concept, I simply included the
fix here.
A new example, `animation_masks`, has been added. It demonstrates how to
toggle masks on and off for specific portions of a skin.
This is part of #14395, but I'm going to defer closing that issue until
we have additive blending.
[essentially as implemented here]:
https://docs.unity3d.com/560/Documentation/Manual/class-AvatarMask.html
[*layered blend per bone*]:
https://dev.epicgames.com/documentation/en-us/unreal-engine/using-layered-animations-in-unreal-engine
[*blend filters*]:
https://docs.godotengine.org/en/stable/tutorials/animation/animation_tree.html
## Migration Guide
* The serialized format of animation graphs has changed with the
addition of animation masks. To upgrade animation graph RON files, add
`mask` and `mask_groups` fields as appropriate. (They can be safely set
to zero.)
Adds a new `Handle<Storage>` asset type that can be used as a render
asset, particularly for use with `AsBindGroup`.
Closes: #13658
# Objective
Allow users to create storage buffers in the main world without having
to access the `RenderDevice`. While this resource is technically
available, it's bad form to use in the main world and requires mixing
rendering details with main world code. Additionally, this makes storage
buffers easier to use with `AsBindGroup`, particularly in the following
scenarios:
- Sharing the same buffers between a compute stage and material shader.
We already have examples of this for storage textures (see game of life
example) and these changes allow a similar pattern to be used with
storage buffers.
- Preventing repeated gpu upload (see the previous easier to use `Vec`
`AsBindGroup` option).
- Allow initializing custom materials using `Default`. Previously, the
lack of a `Default` implement for the raw `wgpu::Buffer` type made
implementing a `AsBindGroup + Default` bound difficult in the presence
of buffers.
## Solution
Adds a new `Handle<Storage>` asset type that is prepared into a
`GpuStorageBuffer` render asset. This asset can either be initialized
with a `Vec<u8>` of properly aligned data or with a size hint. Users can
modify the underlying `wgpu::BufferDescriptor` to provide additional
usage flags.
## Migration Guide
The `AsBindGroup` `storage` attribute has been modified to reference the
new `Handle<Storage>` asset instead. Usages of Vec` should be converted
into assets instead.
---------
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
# Objective
Add `bevy_picking` sprite backend as part of the `bevy_mod_picking`
upstreamening (#12365).
## Solution
More or less a copy/paste from `bevy_mod_picking`, with the changes
[here](https://github.com/aevyrie/bevy_mod_picking/pull/354). I'm
putting that link here since those changes haven't yet made it through
review, so should probably be reviewed on their own.
## Testing
I couldn't find any sprite-backend-specific tests in `bevy_mod_picking`
and unfortunately I'm not familiar enough with Bevy's testing patterns
to write tests for code that relies on windowing and input. I'm willing
to break the pointer hit system into testable blocks and add some more
modular tests if that's deemed important enough to block, otherwise I
can open an issue for adding tests as follow-up.
## Follow-up work
- More docs/tests
- Ignore pick events on transparent sprite pixels with potential opt-out
---------
Co-authored-by: Aevyrie <aevyrie@gmail.com>
# Objective
- Remove the `wgpu_trace` feature while still making it easy/possible to
record wgpu traces for debugging.
- Close#14725.
- Get a taste of the bevy codebase. :P
## Solution
This PR performs the above objective by removing the `wgpu_trace`
feature from all `Cargo.toml` files.
However, wgpu traces are still useful for debugging - but to record
them, you need to pass in a directory path to store the traces in. To
avoid forcing users into manually creating the renderer,
`bevy_render::settings::WgpuSettings` now has a `trace_path` field, so
that all of Bevy's automatic initialization can happen while still
allowing for tracing.
## Testing
- Did you test these changes? If so, how?
- I have tested these changes, but only via running `cargo run -p ci`. I
am hoping the Github Actions workflows will catch anything I missed.
- Are there any parts that need more testing?
- I do not believe so.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
- If you want to test these changes, I have updated the debugging guide
(`docs/debugging.md`) section on WGPU Tracing.
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
- I ran the above command on a Windows 10 64-bit (x64) machine, using
the `stable-x86_64-pc-windows-msvc` toolchain. I do not have anything
set up for other platforms or targets (though I can't imagine this needs
testing on other platforms).
---
## Migration Guide
1. The `bevy/wgpu_trace`, `bevy_render/wgpu_trace`, and
`bevy_internal/wgpu_trace` features no longer exist. Remove them from
your `Cargo.toml`, CI, tooling, and what-not.
2. Follow the instructions in the updated `docs/debugging.md` file in
the repository, under the WGPU Tracing section.
Because of the changes made, you can now generate traces to any path,
rather than the hardcoded `%WorkspaceRoot%/wgpu_trace` (where
`%WorkspaceRoot%` is... the root of your crate's workspace) folder.
(If WGPU hasn't restored tracing functionality...) Do note that WGPU has
not yet restored tracing functionality. However, once it does, the above
should be sufficient to generate new traces.
---------
Co-authored-by: TrialDragon <31419708+TrialDragon@users.noreply.github.com>
# Objective
- The goal of this PR is to make it possible to move the density texture
of a `FogVolume` over time in order to create dynamic effects like fog
moving in the wind.
- You could theoretically move the `FogVolume` itself, but this is not
ideal, because the `FogVolume` AABB would eventually leave the area. If
you want an area to remain foggy while also creating the impression that
the fog is moving in the wind, a scrolling density texture is a better
solution.
## Solution
- The PR adds a `density_texture_offset` field to the `FogVolume`
component. This offset is in the UVW coordinates of the density texture,
meaning that a value of `(0.5, 0.0, 0.0)` moves the 3d texture by half
along the x-axis.
- Values above 1.0 are wrapped, a 1.5 offset is the same as a 0.5
offset. This makes it so that the density texture wraps around on the
other side, meaning that a repeating 3d noise texture can seamlessly
scroll forever. It also makes it easy to move the density texture over
time by simply increasing the offset every frame.
## Testing
- A `scrolling_fog` example has been added to demonstrate the feature.
It uses the offset to scroll a repeating 3d noise density texture to
create the impression of fog moving in the wind.
- The camera is looking at a pillar with the sun peaking behind it. This
highlights the effect the changing density has on the volumetric
lighting interactions.
- Temporal anti-aliasing combined with the `jitter` option of
`VolumetricFogSettings` is used to improve the quality of the effect.
---
## Showcase
https://github.com/user-attachments/assets/3aa50ebd-771c-4c99-ab5d-255c0c3be1a8
# Objective
Fixes#14782
## Solution
Enable the lint and fix all upcoming hints (`--fix`). Also tried to
figure out the false-positive (see review comment). Maybe split this PR
up into multiple parts where only the last one enables the lint, so some
can already be merged resulting in less many files touched / less
potential for merge conflicts?
Currently, there are some cases where it might be easier to read the
code with the qualifier, so perhaps remove the import of it and adapt
its cases? In the current stage it's just a plain adoption of the
suggestions in order to have a base to discuss.
## Testing
`cargo clippy` and `cargo run -p ci` are happy.
# Objective
fixes#14569
## Solution
added an example to the diagnostic examples and linked the code to the
docs of the diagnostic library itself.
## Testing
I tested locally on my laptop in a web browser. Looked fine. You are
able to collapse the whole "intro" part of the doc to get to the links
sooner (for those who may think that including the example code here is
annoying to scroll through)
I would like people to run ```cargo doc``` and go the bevy_diagnostic
page to see if they have any issues or suggestions.
---
## Showcase
<img width="1067" alt="Screenshot 2024-08-14 at 12 52 16"
src="https://github.com/user-attachments/assets/70b6c18a-0bb9-4656-ba53-c416f62c6116">
---------
Co-authored-by: dpeke <dpekelis@funstage.com>
Makes the newly merged picking usable for UI elements.
currently it both triggers the events, as well as sends them as throught
commands.trigger_targets. We should probably figure out if this is
needed for them all.
# Objective
Hooks up obserers and picking for a very simple example
## Solution
upstreamed the UI picking backend from bevy_mod_picking
## Testing
tested with the new example picking/simple_picking.rs
---
---------
Co-authored-by: Lixou <82600264+DasLixou@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>
# Objective
This PR is a follow-up to #14703. I forgot to also add the flags from
`package.metadata.docs.rs` to the docs build.
## Solution
As [discussed on
Discord](https://discord.com/channels/691052431525675048/1272629407659589663/1272643734260940940),
I added the missing flags to `docs.yml`.
I also updated `rustc-args` to properly make use of the array (I think
the value has to be either a space-separated string *or* an array of
strings but not an array of space-separated strings 😆)
# Objective
- Fixes#14697
## Solution
This PR modifies the existing `all_tuples!` macro to optionally accept a
`#[doc(fake_variadic)]` attribute in its input. If the attribute is
present, each invocation of the impl macro gets the correct attributes
(i.e. the first impl receives `#[doc(fake_variadic)]` while the other
impls are hidden using `#[doc(hidden)]`.
Impls for the empty tuple (unit type) are left untouched (that's what
the [standard
library](https://doc.rust-lang.org/std/cmp/trait.PartialEq.html#impl-PartialEq-for-())
and
[serde](https://docs.rs/serde/latest/serde/trait.Serialize.html#impl-Serialize-for-())
do).
To work around https://github.com/rust-lang/cargo/issues/8811 and to get
impls on re-exports to correctly show up as variadic, `--cfg docsrs_dep`
is passed when building the docs for the toplevel `bevy` crate.
`#[doc(fake_variadic)]` only works on tuples and fn pointers, so impls
for structs like `AnyOf<(T1, T2, ..., Tn)>` are unchanged.
## Testing
I built the docs locally using `RUSTDOCFLAGS='--cfg docsrs'
RUSTFLAGS='--cfg docsrs_dep' cargo +nightly doc --no-deps --workspace`
and checked the documentation page of a trait both in its original crate
and the re-exported version in `bevy`.
The description should correctly mention for how many tuple items the
trait is implemented.
I added `rustc-args` for docs.rs to the `bevy` crate, I hope there
aren't any other notable crates that re-export `#[doc(fake_variadic)]`
traits.
---
## Showcase
`bevy_ecs::query::QueryData`:
<img width="1015" alt="Screenshot 2024-08-12 at 16 41 28"
src="https://github.com/user-attachments/assets/d40136ed-6731-475f-91a0-9df255cd24e3">
`bevy::ecs::query::QueryData` (re-export):
<img width="1005" alt="Screenshot 2024-08-12 at 16 42 57"
src="https://github.com/user-attachments/assets/71d44cf0-0ab0-48b0-9a51-5ce332594e12">
## Original Description
<details>
Resolves#14697
Submitting as a draft for now, very WIP.
Unfortunately, the docs don't show the variadics nicely when looking at
reexported items.
For example:
`bevy_ecs::bundle::Bundle` correctly shows the variadic impl:
![image](https://github.com/user-attachments/assets/90bf8af1-1d1f-4714-9143-cdd3d0199998)
while `bevy::ecs::bundle::Bundle` (the reexport) shows all the impls
(not good):
![image](https://github.com/user-attachments/assets/439c428e-f712-465b-bec2-481f7bf5870b)
Built using `RUSTDOCFLAGS='--cfg docsrs' cargo +nightly doc --workspace
--no-deps` (`--no-deps` because of wgpu-core).
Maybe I missed something or this is a limitation in the *totally not
private* `#[doc(fake_variadic)]` thingy. In any case I desperately need
some sleep now :))
</details>
This PR is based on top of #12982
# Objective
- Mesh2d currently only has an alpha blended phase. Most sprites don't
need transparency though.
- For some 2d games it can be useful to have a 2d depth buffer
## Solution
- Add an opaque phase to render Mesh2d that don't need transparency
- This phase currently uses the `SortedRenderPhase` to make it easier to
implement based on the already existing transparent phase. A follow up
PR will switch this to `BinnedRenderPhase`.
- Add a 2d depth buffer
- Use that depth buffer in the transparent phase to make sure that
sprites and transparent mesh2d are displayed correctly
## Testing
I added the mesh2d_transforms example that layers many opaque and
transparent mesh2d to make sure they all get displayed correctly. I also
confirmed it works with sprites by modifying that example locally.
---
## Changelog
- Added `AlphaMode2d`
- Added `Opaque2d` render phase
- Camera2d now have a `ViewDepthTexture` component
## Migration Guide
- `ColorMaterial` now contains `AlphaMode2d`. To keep previous
behaviour, use `AlphaMode::BLEND`. If you know your sprite is opaque,
use `AlphaMode::OPAQUE`
## Follow up PRs
- See tracking issue: #13265
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Christopher Biscardi <chris@christopherbiscardi.com>
# Objective
Adds a new `Monitor` component representing a winit `MonitorHandle` that
can be used to spawn new windows and check for system monitor
information.
Closes#12955.
## Solution
For every winit event, check available monitors and spawn them into the
world as components.
## Testing
TODO:
- [x] Test plugging in and unplugging monitor during app runtime
- [x] Test spawning a window on a second monitor by entity id
- [ ] Since this touches winit, test all platforms
---
## Changelog
- Adds a new `Monitor` component that can be queried for information
about available system monitors.
## Migration Guide
- `WindowMode` variants now take a `MonitorSelection`, which can be set
to `MonitorSelection::Primary` to mirror the old behavior.
---------
Co-authored-by: Pascal Hertleif <pascal@technocreatives.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Pascal Hertleif <killercup@gmail.com>
# Objective
- A lot of mid-level rendering apis are hard to figure out because they
don't have any examples
- SpecializedMeshPipeline can be really useful in some cases when you
want more flexibility than a Material without having to go to low level
apis.
## Solution
- Add an example showing how to make a custom `SpecializedMeshPipeline`.
## Testing
- Did you test these changes? If so, how?
- Are there any parts that need more testing?
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
---
## Showcase
The examples just spawns 3 triangles in a triangle pattern.
![image](https://github.com/user-attachments/assets/c3098758-94c4-4775-95e5-1d7c7fb9eb86)
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- Dynamic plugins were deprecated in #13080 due to being unsound. The
plan was to deprecate them in 0.14 and remove them in 0.15.
## Solution
- Remove all dynamic plugin functionality.
- Update documentation to reflect this change.
---
## Migration Guide
Dynamic plugins were deprecated in 0.14 for being unsound, and they have
now been fully removed. Please consider using the alternatives listed in
the `bevy_dynamic_plugin` crate documentation, or worst-case scenario
you may copy the code from 0.14.
# Objective
- Make it possible to know *what* changed your component or resource.
- Common need when debugging, when you want to know the last code
location that mutated a value in the ECS.
- This feature would be very useful for the editor alongside system
stepping.
## Solution
- Adds the caller location to column data.
- Mutations now `track_caller` all the way up to the public API.
- Commands that invoke these functions immediately call
`Location::caller`, and pass this into the functions, instead of the
functions themselves attempting to get the caller. This would not work
for commands which are deferred, as the commands are executed by the
scheduler, not the user's code.
## Testing
- The `component_change_detection` example now shows where the component
was mutated:
```
2024-07-28T06:57:48.946022Z INFO component_change_detection: Entity { index: 1, generation: 1 }: New value: MyComponent(0.0)
2024-07-28T06:57:49.004371Z INFO component_change_detection: Entity { index: 1, generation: 1 }: New value: MyComponent(1.0)
2024-07-28T06:57:49.012738Z WARN component_change_detection: Change detected!
-> value: Ref(MyComponent(1.0))
-> added: false
-> changed: true
-> changed by: examples/ecs/component_change_detection.rs:36:23
```
- It's also possible to inspect change location from a debugger:
<img width="608" alt="image"
src="https://github.com/user-attachments/assets/c90ecc7a-0462-457a-80ae-42e7f5d346b4">
---
## Changelog
- Added source locations to ECS change detection behind the
`track_change_detection` flag.
## Migration Guide
- Added `changed_by` field to many internal ECS functions used with
change detection when the `track_change_detection` feature flag is
enabled. Use Location::caller() to provide the source of the function
call.
---------
Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
# 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.
# Objective
- Fixes: https://github.com/bevyengine/bevy/issues/14036
## Solution
- Add a world space transformation for the environment sample direction.
## Testing
- I have tested the newly added `transform` field using the newly added
`rotate_environment_map` example.
https://github.com/user-attachments/assets/2de77c65-14bc-48ee-b76a-fb4e9782dbdb
## Migration Guide
- Since we have added a new filed to the `EnvironmentMapLight` struct,
users will need to include `..default()` or some rotation value in their
initialization code.
Progress towards https://github.com/bevyengine/bevy/issues/7386.
Following discussion
https://discord.com/channels/691052431525675048/1253260494538539048/1253387942311886960
This Pull Request adds an example to detect system order ambiguities,
and also asserts none exist.
A lot of schedules are ignored in ordered to have the test passing, we
should thrive to make them pass, but in other pull requests.
<details><summary>example output <b>summary</b>, without ignored
schedules</summary>
<p>
```txt
$ cargo run --example ambiguity_detection 2>&1 | grep -C 1 "pairs of syst"
2024-06-21T13:17:55.776585Z WARN bevy_ecs::schedule::schedule: Schedule First has ambiguities.
1 pairs of systems with conflicting data access have indeterminate execution order. Consider adding `before`, `after`, or `ambiguous_with` relationships between these:
-- bevy_time::time_system (in set TimeSystem) and bevy_ecs::event::event_update_system (in set EventUpdates)
--
2024-06-21T13:17:55.782265Z WARN bevy_ecs::schedule::schedule: Schedule PreUpdate has ambiguities.
11 pairs of systems with conflicting data access have indeterminate execution order. Consider adding `before`, `after`, or `ambiguous_with` relationships between these:
-- bevy_pbr::prepass::update_mesh_previous_global_transforms and bevy_asset::server::handle_internal_asset_events
--
2024-06-21T13:17:55.809516Z WARN bevy_ecs::schedule::schedule: Schedule PostUpdate has ambiguities.
63 pairs of systems with conflicting data access have indeterminate execution order. Consider adding `before`, `after`, or `ambiguous_with` relationships between these:
-- bevy_ui::accessibility::image_changed and bevy_ecs::schedule::executor::apply_deferred
--
2024-06-21T13:17:55.816287Z WARN bevy_ecs::schedule::schedule: Schedule Last has ambiguities.
3 pairs of systems with conflicting data access have indeterminate execution order. Consider adding `before`, `after`, or `ambiguous_with` relationships between these:
-- bevy_gizmos::update_gizmo_meshes<bevy_gizmos::aabb::AabbGizmoConfigGroup> (in set UpdateGizmoMeshes) and bevy_gizmos::update_gizmo_meshes<bevy_gizmos::light::LightGizmoConfigGroup> (in set UpdateGizmoMeshes)
--
2024-06-21T13:17:55.831074Z WARN bevy_ecs::schedule::schedule: Schedule ExtractSchedule has ambiguities.
296 pairs of systems with conflicting data access have indeterminate execution order. Consider adding `before`, `after`, or `ambiguous_with` relationships between these:
-- bevy_render::extract_component::extract_components<bevy_sprite::SpriteSource> and bevy_render::render_asset::extract_render_asset<bevy_sprite::mesh2d::material::PreparedMaterial2d<bevy_sprite::mesh2d::color_material::ColorMaterial>>
```
</p>
</details>
To try locally:
```sh
CI_TESTING_CONFIG="./.github/example-run/ambiguity_detection.ron" cargo run --example ambiguity_detection --features "bevy_ci_testing,trace,trace_chrome"
```
---------
Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
# Objective
Fill a gap in the functionality of our curve constructions by allowing
users to easily build cyclic curves from control data.
## Solution
Here I opted for something lightweight and discoverable. There is a new
`CyclicCubicGenerator` trait with a method `to_curve_cyclic` which uses
splines' control data to create curves that are cyclic. For now, its
signature is exactly like that of `CubicGenerator` — `to_curve_cyclic`
just yields a `CubicCurve`:
```rust
/// Implement this on cubic splines that can generate a cyclic cubic curve from their spline parameters.
///
/// This makes sense only when the control data can be interpreted cyclically.
pub trait CyclicCubicGenerator<P: VectorSpace> {
/// Build a cyclic [`CubicCurve`] by computing the interpolation coefficients for each curve segment.
fn to_curve_cyclic(&self) -> CubicCurve<P>;
}
```
This trait has been implemented for `CubicHermite`,
`CubicCardinalSpline`, `CubicBSpline`, and `LinearSpline`:
<img width="753" alt="Screenshot 2024-07-01 at 8 58 27 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/69ae0802-3b78-4fb9-b73a-6f842cf3b33c">
<img width="628" alt="Screenshot 2024-07-01 at 9 00 14 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/2992175a-a96c-40fc-b1a1-5206c3572cde">
<img width="606" alt="Screenshot 2024-07-01 at 8 59 36 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/9e99eb3a-dbe6-42da-886c-3d3e00410d03">
<img width="603" alt="Screenshot 2024-07-01 at 8 59 01 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/d037bc0c-396a-43af-ab5c-fad9a29417ef">
(Each type pictured respectively with the control points rendered as
green spheres; tangents not pictured in the case of the Hermite spline.)
These curves are all parametrized so that the output of `to_curve` and
the output of `to_curve_cyclic` are similar. For instance, in
`CubicCardinalSpline`, the first output segment is a curve segment
joining the first and second control points in each, although it is
constructed differently. In the other cases, the segments from
`to_curve` are a subset of those in `to_curve_cyclic`, with the new
segments appearing at the end.
## Testing
I rendered cyclic splines from control data and made sure they looked
reasonable. Existing tests are intact for splines where previous code
was modified. (Note that the coefficient computation for cyclic spline
segments is almost verbatim identical to that of their non-cyclic
counterparts.)
The Bezier benchmarks also look fine.
---
## Changelog
- Added `CyclicCubicGenerator` trait to `bevy_math::cubic_splines` for
creating cyclic curves from control data.
- Implemented `CyclicCubicGenerator` for `CubicHermite`,
`CubicCardinalSpline`, `CubicBSpline`, and `LinearSpline`.
- `bevy_math` now depends on `itertools`.
---
## Discussion
### Design decisions
The biggest thing here is just the approach taken in the first place:
namely, the cyclic constructions use new methods on the same old
structs. This choice was made to reduce friction and increase
discoverability but also because creating new ones just seemed
unnecessary: the underlying data would have been the same, so creating
something like "`CyclicCubicBSpline`" whose internally-held control data
is regarded as cyclic in nature doesn't really accomplish much — the end
result for the user is basically the same either way.
Similarly, I don't presently see a pressing need for `to_curve_cyclic`
to output something other than a `CubicCurve`, although changing this in
the future may be useful. See below.
A notable omission here is that `CyclicCubicGenerator` is not
implemented for `CubicBezier`. This is not a gap waiting to be filled —
`CubicBezier` just doesn't have enough data to join its start with its
end without just making up the requisite control points wholesale. In
all the cases where `CyclicCubicGenerator` has been implemented here,
the fashion in which the ends are connected is quite natural and follows
the semantics of the associated spline construction.
### Future direction
There are two main things here:
1. We should investigate whether we should do something similar for
NURBS. I just don't know that much about NURBS at the moment, so I
regarded this as out of scope for the PR.
2. We may eventually want to change the output type of
`CyclicCubicGenerator::to_curve_cyclic` to a type which reifies the
cyclic nature of the curve output. This wasn't done in this PR because
I'm unsure how much value a type-level guarantee of cyclicity actually
has, but if some useful features make sense only in the case of cyclic
curves, this might be worth pursuing.
Currently, volumetric fog is global and affects the entire scene
uniformly. This is inadequate for many use cases, such as local smoke
effects. To address this problem, this commit introduces *fog volumes*,
which are axis-aligned bounding boxes (AABBs) that specify fog
parameters inside their boundaries. Such volumes can also specify a
*density texture*, a 3D texture of voxels that specifies the density of
the fog at each point.
To create a fog volume, add a `FogVolume` component to an entity (which
is included in the new `FogVolumeBundle` convenience bundle). Like light
probes, a fog volume is conceptually a 1×1×1 cube centered on the
origin; a transform can be used to position and resize this region. Many
of the fields on the existing `VolumetricFogSettings` have migrated to
the new `FogVolume` component. `VolumetricFogSettings` on a camera is
still needed to enable volumetric fog. However, by itself
`VolumetricFogSettings` is no longer sufficient to enable volumetric
fog; a `FogVolume` must be present. Applications that wish to retain the
old global fog behavior can simply surround the scene with a large fog
volume.
By way of implementation, this commit converts the volumetric fog shader
from a full-screen shader to one applied to a mesh. The strategy is
different depending on whether the camera is inside or outside the fog
volume. If the camera is inside the fog volume, the mesh is simply a
plane scaled to the viewport, effectively falling back to a full-screen
pass. If the camera is outside the fog volume, the mesh is a cube
transformed to coincide with the boundaries of the fog volume's AABB.
Importantly, in the latter case, only the front faces of the cuboid are
rendered. Instead of treating the boundaries of the fog as a sphere
centered on the camera position, as we did prior to this patch, we
raytrace the far planes of the AABB to determine the portion of each ray
contained within the fog volume. We then raymarch in shadow map space as
usual. If a density texture is present, we modulate the fixed density
value with the trilinearly-interpolated value from that texture.
Furthermore, this patch introduces optional jitter to fog volumes,
intended for use with TAA. This modifies the position of the ray from
frame to frame using interleaved gradient noise, in order to reduce
aliasing artifacts. Many implementations of volumetric fog in games use
this technique. Note that this patch makes no attempt to write a motion
vector; this is because when a view ray intersects multiple voxels
there's no single direction of motion. Consequently, fog volumes can
have ghosting artifacts, but because fog is "ghostly" by its nature,
these artifacts are less objectionable than they would be for opaque
objects.
A new example, `fog_volumes`, has been added. It demonstrates a single
fog volume containing a voxelized representation of the Stanford bunny.
The existing `volumetric_fog` example has been updated to use the new
local volumetrics API.
## Changelog
### Added
* Local `FogVolume`s are now supported, to localize fog to specific
regions. They can optionally have 3D density voxel textures for precise
control over the distribution of the fog.
### Changed
* `VolumetricFogSettings` on a camera no longer enables volumetric fog;
instead, it simply enables the processing of `FogVolume`s within the
scene.
## Migration Guide
* A `FogVolume` is now necessary in order to enable volumetric fog, in
addition to `VolumetricFogSettings` on the camera. Existing uses of
volumetric fog can be migrated by placing a large `FogVolume`
surrounding the scene.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
# Objective
The borders example is separate from the rounded borders example. If you
find the borders example, you may miss the rounded borders example.
## Solution
Merge the examples in a basic way, since there is enough room to show
all options at the same time.
I also considered renaming the borders and rounded borders examples so
that they would be located next to each other in repo and UI, but it
felt like having a singular example was better.
## Testing
```
cargo run --example borders
```
---
## Showcase
The merged example looks like this:
![screenshot-2024-07-14-at-13 40
10@2x](https://github.com/user-attachments/assets/0f49cc46-1ca0-40d0-abec-020cbf0fb205)
# Objective
Type data is a **super** useful tool to know about when working with
reflection. However, most users don't fully understand how it works or
that you can use it for more than just object-safe traits.
This is unfortunate because it can be surprisingly simple to manually
create your own type data.
We should have an example detailing how type works, how users can define
their own, and how thy can be used.
## Solution
Added a `type_data` example.
This example goes through all the major points about type data:
- Why we need them
- How they can be defined
- The two ways they can be registered
- A list of common/important type data provided by Bevy
I also thought it might be good to go over the `#[reflect_trait]` macro
as part of this example since it has all the other context, including
how to define type data in places where `#[reflect_trait]` won't work.
Because of this, I removed the `trait_reflection` example.
## Testing
You can run the example locally with the following command:
```
cargo run --example type_data
```
---
## Changelog
- Added the `type_data` example
- Removed the `trait_reflection` example
This commit creates a new built-in postprocessing shader that's designed
to hold miscellaneous postprocessing effects, and starts it off with
chromatic aberration. Possible future effects include vignette, film
grain, and lens distortion.
[Chromatic aberration] is a common postprocessing effect that simulates
lenses that fail to focus all colors of light to a single point. It's
often used for impact effects and/or horror games. This patch uses the
technique from *Inside* ([Gjøl & Svendsen 2016]), which allows the
developer to customize the particular color pattern to achieve different
effects. Unity HDRP uses the same technique, while Unreal has a
hard-wired fixed color pattern.
A new example, `post_processing`, has been added, in order to
demonstrate the technique. The existing `post_processing` shader has
been renamed to `custom_post_processing`, for clarity.
[Chromatic aberration]:
https://en.wikipedia.org/wiki/Chromatic_aberration
[Gjøl & Svendsen 2016]:
https://github.com/playdeadgames/publications/blob/master/INSIDE/rendering_inside_gdc2016.pdf
![Screenshot 2024-06-04
180304](https://github.com/bevyengine/bevy/assets/157897/3631c64f-a615-44fe-91ca-7f04df0a54b2)
![Screenshot 2024-06-04
180743](https://github.com/bevyengine/bevy/assets/157897/ee055cbf-4314-49c5-8bfa-8d8a17bd52bb)
## Changelog
### Added
* Chromatic aberration is now available as a built-in postprocessing
effect. To use it, add `ChromaticAberration` to your camera.
# Objective
Add basic bubbling to observers, modeled off `bevy_eventlistener`.
## Solution
- Introduce a new `Traversal` trait for components which point to other
entities.
- Provide a default `TraverseNone: Traversal` component which cannot be
constructed.
- Implement `Traversal` for `Parent`.
- The `Event` trait now has an associated `Traversal` which defaults to
`TraverseNone`.
- Added a field `bubbling: &mut bool` to `Trigger` which can be used to
instruct the runner to bubble the event to the entity specified by the
event's traversal type.
- Added an associated constant `SHOULD_BUBBLE` to `Event` which
configures the default bubbling state.
- Added logic to wire this all up correctly.
Introducing the new associated information directly on `Event` (instead
of a new `BubblingEvent` trait) lets us dispatch both bubbling and
non-bubbling events through the same api.
## Testing
I have added several unit tests to cover the common bugs I identified
during development. Running the unit tests should be enough to validate
correctness. The changes effect unsafe portions of the code, but should
not change any of the safety assertions.
## Changelog
Observers can now bubble up the entity hierarchy! To create a bubbling
event, change your `Derive(Event)` to something like the following:
```rust
#[derive(Component)]
struct MyEvent;
impl Event for MyEvent {
type Traverse = Parent; // This event will propagate up from child to parent.
const AUTO_PROPAGATE: bool = true; // This event will propagate by default.
}
```
You can dispatch a bubbling event using the normal
`world.trigger_targets(MyEvent, entity)`.
Halting an event mid-bubble can be done using
`trigger.propagate(false)`. Events with `AUTO_PROPAGATE = false` will
not propagate by default, but you can enable it using
`trigger.propagate(true)`.
If there are multiple observers attached to a target, they will all be
triggered by bubbling. They all share a bubbling state, which can be
accessed mutably using `trigger.propagation_mut()` (`trigger.propagate`
is just sugar for this).
You can choose to implement `Traversal` for your own types, if you want
to bubble along a different structure than provided by `bevy_hierarchy`.
Implementers must be careful never to produce loops, because this will
cause bevy to hang.
## Migration Guide
+ Manual implementations of `Event` should add associated type `Traverse
= TraverseNone` and associated constant `AUTO_PROPAGATE = false`;
+ `Trigger::new` has new field `propagation: &mut Propagation` which
provides the bubbling state.
+ `ObserverRunner` now takes the same `&mut Propagation` as a final
parameter.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Function reflection requires a lot of macro code generation in the form
of several `all_tuples!` invocations, as well as impls generated in the
`Reflect` derive macro.
Seeing as function reflection is currently a bit more niche, it makes
sense to gate it all behind a feature.
## Solution
Add a `functions` feature to `bevy_reflect`, which can be enabled in
Bevy using the `reflect_functions` feature.
## Testing
You can test locally by running:
```
cargo test --package bevy_reflect
```
That should ensure that everything still works with the feature
disabled.
To test with the feature on, you can run:
```
cargo test --package bevy_reflect --features functions
```
---
## Changelog
- Moved function reflection behind a Cargo feature
(`bevy/reflect_functions` and `bevy_reflect/functions`)
- Add `IntoFunction` export in `bevy_reflect::prelude`
## Internal Migration Guide
> [!important]
> Function reflection was introduced as part of the 0.15 dev cycle. This
migration guide was written for developers relying on `main` during this
cycle, and is not a breaking change coming from 0.14.
Function reflection is now gated behind a feature. To use function
reflection, enable the feature:
- If using `bevy_reflect` directly, enable the `functions` feature
- If using `bevy`, enable the `reflect_functions` feature
# Objective
- Moves the smooth_follow.rs into movement directory in examples
- Fixes#14241
## Solution
- Move the smooth_follow.rs to movement dir in examples.
_copy-pasted from my doc comment in the code_
# Objective
This example shows how to properly handle player input, advance a
physics simulation in a fixed timestep, and display the results.
The classic source for how and why this is done is Glenn Fiedler's
article [Fix Your
Timestep!](https://gafferongames.com/post/fix_your_timestep/).
## Motivation
The naive way of moving a player is to just update their position like
so:
```rust
transform.translation += velocity;
```
The issue here is that the player's movement speed will be tied to the
frame rate.
Faster machines will move the player faster, and slower machines will
move the player slower.
In fact, you can observe this today when running some old games that did
it this way on modern hardware!
The player will move at a breakneck pace.
The more sophisticated way is to update the player's position based on
the time that has passed:
```rust
transform.translation += velocity * time.delta_seconds();
```
This way, velocity represents a speed in units per second, and the
player will move at the same speed regardless of the frame rate.
However, this can still be problematic if the frame rate is very low or
very high. If the frame rate is very low, the player will move in large
jumps. This may lead to a player moving in such large jumps that they
pass through walls or other obstacles. In general, you cannot expect a
physics simulation to behave nicely with *any* delta time. Ideally, we
want to have some stability in what kinds of delta times we feed into
our physics simulation.
The solution is using a fixed timestep. This means that we advance the
physics simulation by a fixed amount at a time. If the real time that
passed between two frames is less than the fixed timestep, we simply
don't advance the physics simulation at all.
If it is more, we advance the physics simulation multiple times until we
catch up. You can read more about how Bevy implements this in the
documentation for
[`bevy::time::Fixed`](https://docs.rs/bevy/latest/bevy/time/struct.Fixed.html).
This leaves us with a last problem, however. If our physics simulation
may advance zero or multiple times per frame, there may be frames in
which the player's position did not need to be updated at all, and some
where it is updated by a large amount that resulted from running the
physics simulation multiple times. This is physically correct, but
visually jarring. Imagine a player moving in a straight line, but
depending on the frame rate, they may sometimes advance by a large
amount and sometimes not at all. Visually, we want the player to move
smoothly. This is why we need to separate the player's position in the
physics simulation from the player's position in the visual
representation. The visual representation can then be interpolated
smoothly based on the last and current actual player position in the
physics simulation.
This is a tradeoff: every visual frame is now slightly lagging behind
the actual physical frame, but in return, the player's movement will
appear smooth. There are other ways to compute the visual representation
of the player, such as extrapolation. See the [documentation of the
lightyear
crate](https://cbournhonesque.github.io/lightyear/book/concepts/advanced_replication/visual_interpolation.html)
for a nice overview of the different methods and their tradeoffs.
## Implementation
- The player's velocity is stored in a `Velocity` component. This is the
speed in units per second.
- The player's current position in the physics simulation is stored in a
`PhysicalTranslation` component.
- The player's previous position in the physics simulation is stored in
a `PreviousPhysicalTranslation` component.
- The player's visual representation is stored in Bevy's regular
`Transform` component.
- Every frame, we go through the following steps:
- Advance the physics simulation by one fixed timestep in the
`advance_physics` system.
This is run in the `FixedUpdate` schedule, which runs before the
`Update` schedule.
- Update the player's visual representation in the
`update_displayed_transform` system.
This interpolates between the player's previous and current position in
the physics simulation.
- Update the player's velocity based on the player's input in the
`handle_input` system.
## Relevant Issues
Related to #1259.
I'm also fairly sure I've seen an issue somewhere made by
@alice-i-cecile about showing how to move a character correctly in a
fixed timestep, but I cannot find it.
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>
# Replace ab_glyph with the more capable cosmic-text
Fixes#7616.
Cosmic-text is a more mature text-rendering library that handles scripts
and ligatures better than ab_glyph, it can also handle system fonts
which can be implemented in bevy in the future
Rebase of https://github.com/bevyengine/bevy/pull/8808
## Changelog
Replaces text renderer ab_glyph with cosmic-text
The definition of the font size has changed with the migration to cosmic
text. The behavior is now consistent with other platforms (e.g. the
web), where the font size in pixels measures the height of the font (the
distance between the top of the highest ascender and the bottom of the
lowest descender). Font sizes in your app need to be rescaled to
approximately 1.2x smaller; for example, if you were using a font size
of 60.0, you should now use a font size of 50.0.
## Migration guide
- `Text2dBounds` has been replaced with `TextBounds`, and it now accepts
`Option`s to the bounds, instead of using `f32::INFINITY` to inidicate
lack of bounds
- Textsizes should be changed, dividing the current size with 1.2 will
result in the same size as before.
- `TextSettings` struct is removed
- Feature `subpixel_alignment` has been removed since cosmic-text
already does this automatically
- TextBundles and things rendering texts requires the `CosmicBuffer`
Component on them as well
## Suggested followups:
- TextPipeline: reconstruct byte indices for keeping track of eventual
cursors in text input
- TextPipeline: (future work) split text entities into section entities
- TextPipeline: (future work) text editing
- Support line height as an option. Unitless `1.2` is the default used
in browsers (1.2x font size).
- Support System Fonts and font families
- Example showing of animated text styles. Eg. throbbing hyperlinks
---------
Co-authored-by: tigregalis <anak.harimau@gmail.com>
Co-authored-by: Nico Burns <nico@nicoburns.com>
Co-authored-by: sam edelsten <samedelsten1@gmail.com>
Co-authored-by: Dimchikkk <velo.app1@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
# 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>
# Objective
It's not always obvious what the default value for `RenderLayers`
represents. It is documented, but since it's an implementation of a
trait method the documentation may or may not be shown depending on the
IDE.
## Solution
Add documentation to the `none` method that explicitly calls out the
difference.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>