# Objective
- get closer to being able to load gltfs without using bevy_render
## Solution
- Split bevy_camera out of bevy_render
- Builds on #19943
- Im sorry for the big diff, i tried to minimize it as much as i can by
using re-exports. This also prevents most breaking changes, but there
are still a couple.
## Testing
- 3d_scene looks good
# Objective
Change `ScrollPosition` to newtype `Vec2`. It's easier to work with a
`Vec2` wrapper than individual fields.
I'm not sure why this wasn't newtyped to start with. Maybe the intent
was to support responsive coordinates eventually but that probably isn't
very useful or straightforward to implement. And even if we do want to
support responsive coords in the future, it can newtype `Val2`.
## Solution
Change `ScrollPosition` to newtype `Vec2`.
Also added some extra details to the doc comments.
## Testing
Try the `scroll` example.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
I set out with one simple goal: clearly document the differences between
each of the component lifecycle events via module docs.
Unfortunately, no such module existed: the various lifecycle code was
scattered to the wind.
Without a unified module, it's very hard to discover the related types,
and there's nowhere good to put my shiny new documentation.
## Solution
1. Unify the assorted types into a single
`bevy_ecs::component_lifecycle` module.
2. Write docs.
3. Write a migration guide.
## Testing
Thanks CI!
## Follow-up
1. The lifecycle event names are pretty confusing, especially
`OnReplace`. We should consider renaming those. No bikeshedding in my PR
though!
2. Observers need real module docs too :(
3. Any additional functional changes should be done elsewhere; this is a
simple docs and re-org PR.
---------
Co-authored-by: theotherphil <phil.j.ellison@gmail.com>
# Objective
Add specialized UI transform `Component`s and fix some related problems:
* Animating UI elements by modifying the `Transform` component of UI
nodes doesn't work very well because `ui_layout_system` overwrites the
translations each frame. The `overflow_debug` example uses a horrible
hack where it copies the transform into the position that'll likely
cause a panic if any users naively copy it.
* Picking ignores rotation and scaling and assumes UI nodes are always
axis aligned.
* The clipping geometry stored in `CalculatedClip` is wrong for rotated
and scaled elements.
* Transform propagation is unnecessary for the UI, the transforms can be
updated during layout updates.
* The UI internals use both object-centered and top-left-corner-based
coordinates systems for UI nodes. Depending on the context you have to
add or subtract the half-size sometimes before transforming between
coordinate spaces. We should just use one system consistantly so that
the transform can always be directly applied.
* `Transform` doesn't support responsive coordinates.
## Solution
* Unrequire `Transform` from `Node`.
* New components `UiTransform`, `UiGlobalTransform`:
- `Node` requires `UiTransform`, `UiTransform` requires
`UiGlobalTransform`
- `UiTransform` is a 2d-only equivalent of `Transform` with a
translation in `Val`s.
- `UiGlobalTransform` newtypes `Affine2` and is updated in
`ui_layout_system`.
* New helper functions on `ComputedNode` for mapping between viewport
and local node space.
* The cursor position is transformed to local node space during picking
so that it respects rotations and scalings.
* To check if the cursor hovers a node recursively walk up the tree to
the root checking if any of the ancestor nodes clip the point at the
cursor. If the point is clipped the interaction is ignored.
* Use object-centered coordinates for UI nodes.
* `RelativeCursorPosition`'s coordinates are now object-centered with
(0,0) at the the center of the node and the corners at (±0.5, ±0.5).
* Replaced the `normalized_visible_node_rect: Rect` field of
`RelativeCursorPosition` with `cursor_over: bool`, which is set to true
when the cursor is over an unclipped point on the node. The visible area
of the node is not necessarily a rectangle, so the previous
implementation didn't work.
This should fix all the logical bugs with non-axis aligned interactions
and clipping. Rendering still needs changes but they are far outside the
scope of this PR.
Tried and abandoned two other approaches:
* New `transform` field on `Node`, require `GlobalTransform` on `Node`,
and unrequire `Transform` on `Node`. Unrequiring `Transform` opts out of
transform propagation so there is then no conflict with updating the
`GlobalTransform` in `ui_layout_system`. This was a nice change in its
simplicity but potentially confusing for users I think, all the
`GlobalTransform` docs mention `Transform` and having special rules for
how it's updated just for the UI is unpleasently surprising.
* New `transform` field on `Node`. Unrequire `Transform` on `Node`. New
`transform: Affine2` field on `ComputedNode`.
This was okay but I think most users want a separate specialized UI
transform components. The fat `ComputedNode` doesn't work well with
change detection.
Fixes#18929, #18930
## Testing
There is an example you can look at:
```
cargo run --example ui_transform
```
Sometimes in the example if you press the rotate button couple of times
the first glyph from the top label disappears , I'm not sure what's
causing it yet but I don't think it's related to this PR.
## Migration Guide
New specialized 2D UI transform components `UiTransform` and
`UiGlobalTransform`. `UiTransform` is a 2d-only equivalent of
`Transform` with a translation in `Val`s. `UiGlobalTransform` newtypes
`Affine2` and is updated in `ui_layout_system`.
`Node` now requires `UiTransform` instead of `Transform`. `UiTransform`
requires `UiGlobalTransform`.
In previous versions of Bevy `ui_layout_system` would overwrite UI
node's `Transform::translation` each frame. `UiTransform`s aren't
overwritten and there is no longer any need for systems that cache and
rewrite the transform for translated UI elements.
`RelativeCursorPosition`'s coordinates are now object-centered with
(0,0) at the the center of the node and the corners at (±0.5, ±0.5). Its
`normalized_visible_node_rect` field has been removed and replaced with
a new `cursor_over: bool` field which is set to true when the cursor is
hovering an unclipped area of the UI node.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Allowing drawing of UI nodes with a gradient instead of a flat color.
## Solution
The are three gradient structs corresponding to the three types of
gradients supported: `LinearGradient`, `ConicGradient` and
`RadialGradient`. These are then wrapped in a `Gradient` enum
discriminator which has `Linear`, `Conic` and `Radial` variants.
Each gradient type consists of the geometric properties for that
gradient and a list of color stops.
Color stops consist of a color, a position or angle and an optional
hint. If no position is specified for a stop, it's evenly spaced between
the previous and following stops. Color stop positions are absolute, if
you specify a list of stops:
```vec
Conic gradients can be used to draw simple pie charts like in CSS:
# Objective
There are two problems this aims to solve.
First, `Entity::index` is currently a `u32`. That means there are
`u32::MAX + 1` possible entities. Not only is that awkward, but it also
make `Entity` allocation more difficult. I discovered this while working
on remote entity reservation, but even on main, `Entities` doesn't
handle the `u32::MAX + 1` entity very well. It can not be batch reserved
because that iterator uses exclusive ranges, which has a maximum upper
bound of `u32::MAX - 1`. In other words, having `u32::MAX` as a valid
index can be thought of as a bug right now. We either need to make that
invalid (this PR), which makes Entity allocation cleaner and makes
remote reservation easier (because the length only needs to be u32
instead of u64, which, in atomics is a big deal), or we need to take
another pass at `Entities` to make it handle the `u32::MAX` index
properly.
Second, `TableRow`, `ArchetypeRow` and `EntityIndex` (a type alias for
u32) all have `u32` as the underlying type. That means using these as
the index type in a `SparseSet` uses 64 bits for the sparse list because
it stores `Option<IndexType>`. By using `NonMaxU32` here, we cut the
memory of that list in half. To my knowledge, `EntityIndex` is the only
thing that would really benefit from this niche. `TableRow` and
`ArchetypeRow` I think are not stored in an `Option` in bulk. But if
they ever are, this would help. Additionally this ensures
`TableRow::INVALID` and `ArchetypeRow::INVALID` never conflict with an
actual row, which in a nice bonus.
As a related note, if we do components as entities where `ComponentId`
becomes `Entity`, the the `SparseSet<ComponentId>` will see a similar
memory improvement too.
## Solution
Create a new type `EntityRow` that wraps `NonMaxU32`, similar to
`TableRow` and `ArchetypeRow`.
Change `Entity::index` to this type.
## Downsides
`NonMax` is implemented as a `NonZero` with a binary inversion. That
means accessing and storing the value takes one more instruction. I
don't think that's a big deal, but it's worth mentioning.
As a consequence, `to_bits` uses `transmute` to skip the inversion which
keeps it a nop. But that also means that ordering has now flipped. In
other words, higher indices are considered less than lower indices. I
don't think that's a problem, but it's also worth mentioning.
## Alternatives
We could keep the index as a u32 type and just document that `u32::MAX`
is invalid, modifying `Entities` to ensure it never gets handed out.
(But that's not enforced by the type system.) We could still take
advantage of the niche here in `ComponentSparseSet`. We'd just need some
unsafe manual conversions, which is probably fine, but opens up the
possibility for correctness problems later.
We could change `Entities` to fully support the `u32::MAX` index. (But
that makes `Entities` more complex and potentially slightly slower.)
## Testing
- CI
- A few tests were changed because they depend on different ordering and
`to_bits` values.
## Future Work
- It might be worth removing the niche on `Entity::generation` since
there is now a different niche.
- We could move `Entity::generation` into it's own type too for clarity.
- We should change `ComponentSparseSet` to take advantage of the new
niche. (This PR doesn't change that yet.)
- Consider removing or updating `Identifier`. This is only used for
`Entity`, so it might be worth combining since `Entity` is now more
unique.
---------
Co-authored-by: atlv <email@atlasdostal.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
# Objective
The goal of `bevy_platform_support` is to provide a set of platform
agnostic APIs, alongside platform-specific functionality. This is a high
traffic crate (providing things like HashMap and Instant). Especially in
light of https://github.com/bevyengine/bevy/discussions/18799, it
deserves a friendlier / shorter name.
Given that it hasn't had a full release yet, getting this change in
before Bevy 0.16 makes sense.
## Solution
- Rename `bevy_platform_support` to `bevy_platform`.
# Objective
In #17905 we swapped to a named field on `ChildOf` to help resolve
variable naming ambiguity of child vs parent (ex: `child_of.parent`
clearly reads as "I am accessing the parent of the child_of
relationship", whereas `child_of.0` is less clear).
Unfortunately this has the side effect of making initialization less
ideal. `ChildOf { parent }` reads just as well as `ChildOf(parent)`, but
`ChildOf { parent: root }` doesn't read nearly as well as
`ChildOf(root)`.
## Solution
Move back to `ChildOf(pub Entity)` but add a `child_of.parent()`
function and use it for all accesses. The downside here is that users
are no longer "forced" to access the parent field with `parent`
nomenclature, but I think this strikes the right balance.
Take a look at the diff. I think the results provide strong evidence for
this change. Initialization has the benefit of reading much better _and_
of taking up significantly less space, as many lines go from 3 to 1, and
we're cutting out a bunch of syntax in some cases.
Sadly I do think this should land in 0.16 as the cost of doing this
_after_ the relationships migration is high.
# Objective
Unlike for their helper typers, the import paths for
`unique_array::UniqueEntityArray`, `unique_slice::UniqueEntitySlice`,
`unique_vec::UniqueEntityVec`, `hash_set::EntityHashSet`,
`hash_map::EntityHashMap`, `index_set::EntityIndexSet`,
`index_map::EntityIndexMap` are quite redundant.
When looking at the structure of `hashbrown`, we can also see that while
both `HashSet` and `HashMap` have their own modules, the main types
themselves are re-exported to the crate level.
## Solution
Re-export the types in their shared `entity` parent module, and simplify
the imports where they're used.
# Objective
- Optimize static scene performance by marking unchanged subtrees.
-
[bef0209](bef0209de1)
fixes#18255 and #18363.
- Closes#18365
- Includes change from #18321
## Solution
- Mark hierarchy subtrees with dirty bits to avoid transform propagation
where not needed
- This causes a performance regression when spawning many entities, or
when the scene is entirely dynamic.
- This results in massive speedups for largely static scenes.
- In the future we could allow the user to change this behavior, or add
some threshold based on how dynamic the scene is?
## Testing
- Caldera Hotel scene
# Objective
- Optimize static scene performance by marking unchanged subtrees.
## Solution
- Mark hierarchy subtrees with dirty bits to avoid transform propagation
where not needed
- This causes a performance regression when spawning many entities, or
when the scene is entirely dynamic.
- This results in massive speedups for largely static scenes.
- In the future we could allow the user to change this behavior, or add
some threshold based on how dynamic the scene is?
## Testing
- Caldera Hotel scene
# Objective
As discussed in #14275, Bevy is currently too prone to panic, and makes
the easy / beginner-friendly way to do a large number of operations just
to panic on failure.
This is seriously frustrating in library code, but also slows down
development, as many of the `Query::single` panics can actually safely
be an early return (these panics are often due to a small ordering issue
or a change in game state.
More critically, in most "finished" products, panics are unacceptable:
any unexpected failures should be handled elsewhere. That's where the
new
With the advent of good system error handling, we can now remove this.
Note: I was instrumental in a) introducing this idea in the first place
and b) pushing to make the panicking variant the default. The
introduction of both `let else` statements in Rust and the fancy system
error handling work in 0.16 have changed my mind on the right balance
here.
## Solution
1. Make `Query::single` and `Query::single_mut` (and other random
related methods) return a `Result`.
2. Handle all of Bevy's internal usage of these APIs.
3. Deprecate `Query::get_single` and friends, since we've moved their
functionality to the nice names.
4. Add detailed advice on how to best handle these errors.
Generally I like the diff here, although `get_single().unwrap()` in
tests is a bit of a downgrade.
## Testing
I've done a global search for `.single` to track down any missed
deprecated usages.
As to whether or not all the migrations were successful, that's what CI
is for :)
## Future work
~~Rename `Query::get_single` and friends to `Query::single`!~~
~~I've opted not to do this in this PR, and smear it across two releases
in order to ease the migration. Successive deprecations are much easier
to manage than the semantics and types shifting under your feet.~~
Cart has convinced me to change my mind on this; see
https://github.com/bevyengine/bevy/pull/18082#discussion_r1974536085.
## Migration guide
`Query::single`, `Query::single_mut` and their `QueryState` equivalents
now return a `Result`. Generally, you'll want to:
1. Use Bevy 0.16's system error handling to return a `Result` using the
`?` operator.
2. Use a `let else Ok(data)` block to early return if it's an expected
failure.
3. Use `unwrap()` or `Ok` destructuring inside of tests.
The old `Query::get_single` (etc) methods which did this have been
deprecated.
# Objective
There are currently three ways to access the parent stored on a ChildOf
relationship:
1. `child_of.parent` (field accessor)
2. `child_of.get()` (get function)
3. `**child_of` (Deref impl)
I will assert that we should only have one (the field accessor), and
that the existence of the other implementations causes confusion and
legibility issues. The deref approach is heinous, and `child_of.get()`
is significantly less clear than `child_of.parent`.
## Solution
Remove `impl Deref for ChildOf` and `ChildOf::get`.
The one "downside" I'm seeing is that:
```rust
entity.get::<ChildOf>().map(ChildOf::get)
```
Becomes this:
```rust
entity.get::<ChildOf>().map(|c| c.parent)
```
I strongly believe that this is worth the increased clarity and
consistency. I'm also not really a huge fan of the "pass function
pointer to map" syntax. I think most people don't think this way about
maps. They think in terms of a function that takes the item in the
Option and returns the result of some action on it.
## Migration Guide
```rust
// Before
**child_of
// After
child_of.parent
// Before
child_of.get()
// After
child_of.parent
// Before
entity.get::<ChildOf>().map(ChildOf::get)
// After
entity.get::<ChildOf>().map(|c| c.parent)
```
# Objective
- Make transform propagation faster.
## Solution
- Work sharing worker threads
- Parallel tree traversal excluding leaves
- Second cache friendly wide pass over all leaves
- 3-10x faster than main
## Testing
- Tracy
- Caldera hotel is showing 3-7x faster on my M4 Max. Timing for bevy's
existing transform system shifts wildly run to run, so I don't know that
I would advertise a particular number. But this implementation is faster
in a... statistically significant way.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
# Objective
It's difficult to understand or make changes to the UI systems because
of how each system needs to individually track changes to scale factor,
windows and camera targets in local hashmaps, particularly for new
contributors. Any major change inevitably introduces new scale factor
bugs.
Instead of per-system resolution we can resolve the camera target info
for all UI nodes in a system at the start of `PostUpdate` and then store
it per-node in components that can be queried with change detection.
Fixes#17578Fixes#15143
## Solution
Store the UI render target's data locally per node in a component that
is updated in `PostUpdate` before any other UI systems run.
This component can be then be queried with change detection so that UI
systems no longer need to have knowledge of cameras and windows and
don't require fragile custom change detection solutions using local
hashmaps.
## Showcase
Compare `measure_text_system` from main (which has a bug the causes it
to use the wrong scale factor when a node's camera target changes):
```
pub fn measure_text_system(
mut scale_factors_buffer: Local<EntityHashMap<f32>>,
mut last_scale_factors: Local<EntityHashMap<f32>>,
fonts: Res<Assets<Font>>,
camera_query: Query<(Entity, &Camera)>,
default_ui_camera: DefaultUiCamera,
ui_scale: Res<UiScale>,
mut text_query: Query<
(
Entity,
Ref<TextLayout>,
&mut ContentSize,
&mut TextNodeFlags,
&mut ComputedTextBlock,
Option<&UiTargetCamera>,
),
With<Node>,
>,
mut text_reader: TextUiReader,
mut text_pipeline: ResMut<TextPipeline>,
mut font_system: ResMut<CosmicFontSystem>,
) {
scale_factors_buffer.clear();
let default_camera_entity = default_ui_camera.get();
for (entity, block, content_size, text_flags, computed, maybe_camera) in &mut text_query {
let Some(camera_entity) = maybe_camera
.map(UiTargetCamera::entity)
.or(default_camera_entity)
else {
continue;
};
let scale_factor = match scale_factors_buffer.entry(camera_entity) {
Entry::Occupied(entry) => *entry.get(),
Entry::Vacant(entry) => *entry.insert(
camera_query
.get(camera_entity)
.ok()
.and_then(|(_, c)| c.target_scaling_factor())
.unwrap_or(1.0)
* ui_scale.0,
),
};
if last_scale_factors.get(&camera_entity) != Some(&scale_factor)
|| computed.needs_rerender()
|| text_flags.needs_measure_fn
|| content_size.is_added()
{
create_text_measure(
entity,
&fonts,
scale_factor.into(),
text_reader.iter(entity),
block,
&mut text_pipeline,
content_size,
text_flags,
computed,
&mut font_system,
);
}
}
core::mem::swap(&mut *last_scale_factors, &mut *scale_factors_buffer);
}
```
with `measure_text_system` from this PR (which always uses the correct
scale factor):
```
pub fn measure_text_system(
fonts: Res<Assets<Font>>,
mut text_query: Query<
(
Entity,
Ref<TextLayout>,
&mut ContentSize,
&mut TextNodeFlags,
&mut ComputedTextBlock,
Ref<ComputedNodeTarget>,
),
With<Node>,
>,
mut text_reader: TextUiReader,
mut text_pipeline: ResMut<TextPipeline>,
mut font_system: ResMut<CosmicFontSystem>,
) {
for (entity, block, content_size, text_flags, computed, computed_target) in &mut text_query {
// Note: the ComputedTextBlock::needs_rerender bool is cleared in create_text_measure().
if computed_target.is_changed()
|| computed.needs_rerender()
|| text_flags.needs_measure_fn
|| content_size.is_added()
{
create_text_measure(
entity,
&fonts,
computed_target.scale_factor.into(),
text_reader.iter(entity),
block,
&mut text_pipeline,
content_size,
text_flags,
computed,
&mut font_system,
);
}
}
}
```
## Testing
I removed an alarming number of tests from the `layout` module but they
were mostly to do with the deleted camera synchronisation logic. The
remaining tests should all pass now.
The most relevant examples are `multiple_windows` and `split_screen`,
the behaviour of both should be unchanged from main.
---------
Co-authored-by: UkoeHB <37489173+UkoeHB@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
## Objective
A major critique of Bevy at the moment is how boilerplatey it is to
compose (and read) entity hierarchies:
```rust
commands
.spawn(Foo)
.with_children(|p| {
p.spawn(Bar).with_children(|p| {
p.spawn(Baz);
});
p.spawn(Bar).with_children(|p| {
p.spawn(Baz);
});
});
```
There is also currently no good way to statically define and return an
entity hierarchy from a function. Instead, people often do this
"internally" with a Commands function that returns nothing, making it
impossible to spawn the hierarchy in other cases (direct World spawns,
ChildSpawner, etc).
Additionally, because this style of API results in creating the
hierarchy bits _after_ the initial spawn of a bundle, it causes ECS
archetype changes (and often expensive table moves).
Because children are initialized after the fact, we also can't count
them to pre-allocate space. This means each time a child inserts itself,
it has a high chance of overflowing the currently allocated capacity in
the `RelationshipTarget` collection, causing literal worst-case
reallocations.
We can do better!
## Solution
The Bundle trait has been extended to support an optional
`BundleEffect`. This is applied directly to World immediately _after_
the Bundle has fully inserted. Note that this is
[intentionally](https://github.com/bevyengine/bevy/discussions/16920)
_not done via a deferred Command_, which would require repeatedly
copying each remaining subtree of the hierarchy to a new command as we
walk down the tree (_not_ good performance).
This allows us to implement the new `SpawnRelated` trait for all
`RelationshipTarget` impls, which looks like this in practice:
```rust
world.spawn((
Foo,
Children::spawn((
Spawn((
Bar,
Children::spawn(Spawn(Baz)),
)),
Spawn((
Bar,
Children::spawn(Spawn(Baz)),
)),
))
))
```
`Children::spawn` returns `SpawnRelatedBundle<Children, L:
SpawnableList>`, which is a `Bundle` that inserts `Children`
(preallocated to the size of the `SpawnableList::size_hint()`).
`Spawn<B: Bundle>(pub B)` implements `SpawnableList` with a size of 1.
`SpawnableList` is also implemented for tuples of `SpawnableList` (same
general pattern as the Bundle impl).
There are currently three built-in `SpawnableList` implementations:
```rust
world.spawn((
Foo,
Children::spawn((
Spawn(Name::new("Child1")),
SpawnIter(["Child2", "Child3"].into_iter().map(Name::new),
SpawnWith(|parent: &mut ChildSpawner| {
parent.spawn(Name::new("Child4"));
parent.spawn(Name::new("Child5"));
})
)),
))
```
We get the benefits of "structured init", but we have nice flexibility
where it is required!
Some readers' first instinct might be to try to remove the need for the
`Spawn` wrapper. This is impossible in the Rust type system, as a tuple
of "child Bundles to be spawned" and a "tuple of Components to be added
via a single Bundle" is ambiguous in the Rust type system. There are two
ways to resolve that ambiguity:
1. By adding support for variadics to the Rust type system (removing the
need for nested bundles). This is out of scope for this PR :)
2. Using wrapper types to resolve the ambiguity (this is what I did in
this PR).
For the single-entity spawn cases, `Children::spawn_one` does also
exist, which removes the need for the wrapper:
```rust
world.spawn((
Foo,
Children::spawn_one(Bar),
))
```
## This works for all Relationships
This API isn't just for `Children` / `ChildOf` relationships. It works
for any relationship type, and they can be mixed and matched!
```rust
world.spawn((
Foo,
Observers::spawn((
Spawn(Observer::new(|trigger: Trigger<FuseLit>| {})),
Spawn(Observer::new(|trigger: Trigger<Exploded>| {})),
)),
OwnerOf::spawn(Spawn(Bar))
Children::spawn(Spawn(Baz))
))
```
## Macros
While `Spawn` is necessary to satisfy the type system, we _can_ remove
the need to express it via macros. The example above can be expressed
more succinctly using the new `children![X]` macro, which internally
produces `Children::spawn(Spawn(X))`:
```rust
world.spawn((
Foo,
children![
(
Bar,
children![Baz],
),
(
Bar,
children![Baz],
),
]
))
```
There is also a `related!` macro, which is a generic version of the
`children!` macro that supports any relationship type:
```rust
world.spawn((
Foo,
related!(Children[
(
Bar,
related!(Children[Baz]),
),
(
Bar,
related!(Children[Baz]),
),
])
))
```
## Returning Hierarchies from Functions
Thanks to these changes, the following pattern is now possible:
```rust
fn button(text: &str, color: Color) -> impl Bundle {
(
Node {
width: Val::Px(300.),
height: Val::Px(100.),
..default()
},
BackgroundColor(color),
children![
Text::new(text),
]
)
}
fn ui() -> impl Bundle {
(
Node {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
..default(),
},
children![
button("hello", BLUE),
button("world", RED),
]
)
}
// spawn from a system
fn system(mut commands: Commands) {
commands.spawn(ui());
}
// spawn directly on World
world.spawn(ui());
```
## Additional Changes and Notes
* `Bundle::from_components` has been split out into
`BundleFromComponents::from_components`, enabling us to implement
`Bundle` for types that cannot be "taken" from the ECS (such as the new
`SpawnRelatedBundle`).
* The `NoBundleEffect` trait (which implements `BundleEffect`) is
implemented for empty tuples (and tuples of empty tuples), which allows
us to constrain APIs to only accept bundles that do not have effects.
This is critical because the current batch spawn APIs cannot efficiently
apply BundleEffects in their current form (as doing so in-place could
invalidate the cached raw pointers). We could consider allocating a
buffer of the effects to be applied later, but that does have
performance implications that could offset the balance and value of the
batched APIs (and would likely require some refactors to the underlying
code). I've decided to be conservative here. We can consider relaxing
that requirement on those APIs later, but that should be done in a
followup imo.
* I've ported a few examples to illustrate real-world usage. I think in
a followup we should port all examples to the `children!` form whenever
possible (and for cases that require things like SpawnIter, use the raw
APIs).
* Some may ask "why not use the `Relationship` to spawn (ex:
`ChildOf::spawn(Foo)`) instead of the `RelationshipTarget` (ex:
`Children::spawn(Spawn(Foo))`)?". That _would_ allow us to remove the
`Spawn` wrapper. I've explicitly chosen to disallow this pattern.
`Bundle::Effect` has the ability to create _significant_ weirdness.
Things in `Bundle` position look like components. For example
`world.spawn((Foo, ChildOf::spawn(Bar)))` _looks and reads_ like Foo is
a child of Bar. `ChildOf` is in Foo's "component position" but it is not
a component on Foo. This is a huge problem. Now that `Bundle::Effect`
exists, we should be _very_ principled about keeping the "weird and
unintuitive behavior" to a minimum. Things that read like components
_should be the components they appear to be".
## Remaining Work
* The macros are currently trivially implemented using macro_rules and
are currently limited to the max tuple length. They will require a
proc_macro implementation to work around the tuple length limit.
## Next Steps
* Port the remaining examples to use `children!` where possible and raw
`Spawn` / `SpawnIter` / `SpawnWith` where the flexibility of the raw API
is required.
## Migration Guide
Existing spawn patterns will continue to work as expected.
Manual Bundle implementations now require a `BundleEffect` associated
type. Exisiting bundles would have no bundle effect, so use `()`.
Additionally `Bundle::from_components` has been moved to the new
`BundleFromComponents` trait.
```rust
// Before
unsafe impl Bundle for X {
unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self {
}
/* remaining bundle impl here */
}
// After
unsafe impl Bundle for X {
type Effect = ();
/* remaining bundle impl here */
}
unsafe impl BundleFromComponents for X {
unsafe fn from_components<T, F>(ctx: &mut T, func: &mut F) -> Self {
}
}
```
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
Co-authored-by: Emerson Coskey <emerson@coskey.dev>
# Objective
For most UI node entities there's a 1-to-1 mapping from the entity to
its associated Taffy node. Root UI nodes are an exception though, their
corresponding Taffy node in the Taffy tree is also given a parent that
represents the viewport. These viewport Taffy nodes are not removed when
a root UI node is despawned.
Parenting of an existing root UI node with an associated viewport Taffy
node also results in the leak of the viewport node.
These tests fail if added to the `layout` module's tests on the main
branch:
```rust
#[test]
fn no_viewport_node_leak_on_root_despawned() {
let (mut world, mut ui_schedule) = setup_ui_test_world();
let ui_root_entity = world.spawn(Node::default()).id();
// The UI schedule synchronizes Bevy UI's internal `TaffyTree` with the
// main world's tree of `Node` entities.
ui_schedule.run(&mut world);
// Two taffy nodes are added to the internal `TaffyTree` for each root UI entity.
// An implicit taffy node representing the viewport and a taffy node corresponding to the
// root UI entity which is parented to the viewport taffy node.
assert_eq!(
world.resource_mut::<UiSurface>().taffy.total_node_count(),
2
);
world.despawn(ui_root_entity);
// The UI schedule removes both the taffy node corresponding to `ui_root_entity` and its
// parent viewport node.
ui_schedule.run(&mut world);
// Both taffy nodes should now be removed from the internal `TaffyTree`
assert_eq!(
world.resource_mut::<UiSurface>().taffy.total_node_count(),
0
);
}
#[test]
fn no_viewport_node_leak_on_parented_root() {
let (mut world, mut ui_schedule) = setup_ui_test_world();
let ui_root_entity_1 = world.spawn(Node::default()).id();
let ui_root_entity_2 = world.spawn(Node::default()).id();
ui_schedule.run(&mut world);
// There are two UI root entities. Each root taffy node is given it's own viewport node parent,
// so a total of four taffy nodes are added to the `TaffyTree` by the UI schedule.
assert_eq!(
world.resource_mut::<UiSurface>().taffy.total_node_count(),
4
);
// Parent `ui_root_entity_2` onto `ui_root_entity_1` so now only `ui_root_entity_1` is a
// UI root entity.
world
.entity_mut(ui_root_entity_1)
.add_child(ui_root_entity_2);
// Now there is only one root node so the second viewport node is removed by
// the UI schedule.
ui_schedule.run(&mut world);
// There is only one viewport node now, so the `TaffyTree` contains 3 nodes in total.
assert_eq!(
world.resource_mut::<UiSurface>().taffy.total_node_count(),
3
);
}
```
Fixes#17594
## Solution
Change the `UiSurface::entity_to_taffy` to map to `LayoutNode`s. A
`LayoutNode` has a `viewport_id: Option<taffy::NodeId>` field which is
the id of the corresponding implicit "viewport" node if the node is a
root UI node, otherwise it is `None`. When removing or parenting nodes
this field is checked and the implicit viewport node is removed if
present.
## Testing
There are two new tests in `bevy_ui::layout::tests` included with this
PR:
* `no_viewport_node_leak_on_root_despawned`
* `no_viewport_node_leak_on_parented_root`
# Objective
- Contributes to #16877
## Solution
- Moved `hashbrown`, `foldhash`, and related types out of `bevy_utils`
and into `bevy_platform_support`
- Refactored the above to match the layout of these types in `std`.
- Updated crates as required.
## Testing
- CI
---
## Migration Guide
- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::hash`:
- `FixedState`
- `DefaultHasher`
- `RandomState`
- `FixedHasher`
- `Hashed`
- `PassHash`
- `PassHasher`
- `NoOpHash`
- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::collections`:
- `HashMap`
- `HashSet`
- `bevy_utils::hashbrown` has been removed. Instead, import from
`bevy_platform_support::collections` _or_ take a dependency on
`hashbrown` directly.
- `bevy_utils::Entry` has been removed. Instead, import from
`bevy_platform_support::collections::hash_map` or
`bevy_platform_support::collections::hash_set` as appropriate.
- All of the above equally apply to `bevy::utils` and
`bevy::platform_support`.
## Notes
- I left `PreHashMap`, `PreHashMapExt`, and `TypeIdMap` in `bevy_utils`
as they might be candidates for micro-crating. They can always be moved
into `bevy_platform_support` at a later date if desired.
Fixes#17412
## Objective
`Parent` uses the "has a X" naming convention. There is increasing
sentiment that we should use the "is a X" naming convention for
relationships (following #17398). This leaves `Children` as-is because
there is prevailing sentiment that `Children` is clearer than `ParentOf`
in many cases (especially when treating it like a collection).
This renames `Parent` to `ChildOf`.
This is just the implementation PR. To discuss the path forward, do so
in #17412.
## Migration Guide
- The `Parent` component has been renamed to `ChildOf`.
# Objective
The existing `RelationshipSourceCollection` uses `Vec` as the only
possible backing for our relationships. While a reasonable choice,
benchmarking use cases might reveal that a different data type is better
or faster.
For example:
- Not all relationships require a stable ordering between the
relationship sources (i.e. children). In cases where we a) have many
such relations and b) don't care about the ordering between them, a hash
set is likely a better datastructure than a `Vec`.
- The number of children-like entities may be small on average, and a
`smallvec` may be faster
## Solution
- Implement `RelationshipSourceCollection` for `EntityHashSet`, our
custom entity-optimized `HashSet`.
-~~Implement `DoubleEndedIterator` for `EntityHashSet` to make things
compile.~~
- This implementation was cursed and very surprising.
- Instead, by moving the iterator type on `RelationshipSourceCollection`
from an erased RPTIT to an explicit associated type we can add a trait
bound on the offending methods!
- Implement `RelationshipSourceCollection` for `SmallVec`
## Testing
I've added a pair of new tests to make sure this pattern compiles
successfully in practice!
## Migration Guide
`EntityHashSet` and `EntityHashMap` are no longer re-exported in
`bevy_ecs::entity` directly. If you were not using `bevy_ecs` / `bevy`'s
`prelude`, you can access them through their now-public modules,
`hash_set` and `hash_map` instead.
## Notes to reviewers
The `EntityHashSet::Iter` type needs to be public for this impl to be
allowed. I initially renamed it to something that wasn't ambiguous and
re-exported it, but as @Victoronz pointed out, that was somewhat
unidiomatic.
In
1a8564898f,
I instead made the `entity_hash_set` public (and its `entity_hash_set`)
sister public, and removed the re-export. I prefer this design (give me
module docs please), but it leads to a lot of churn in this PR.
Let me know which you'd prefer, and if you'd like me to split that
change out into its own micro PR.
# Objective
It's not immediately obvious that `TargetCamera` only works with UI node
entities. It's natural to assume from looking at something like the
`multiple_windows` example that it will work with everything.
## Solution
Rename `TargetCamera` to `UiTargetCamera`.
## Migration Guide
`TargetCamera` has been renamed to `UiTargetCamera`.
This adds support for one-to-many non-fragmenting relationships (with
planned paths for fragmenting and non-fragmenting many-to-many
relationships). "Non-fragmenting" means that entities with the same
relationship type, but different relationship targets, are not forced
into separate tables (which would cause "table fragmentation").
Functionally, this fills a similar niche as the current Parent/Children
system. The biggest differences are:
1. Relationships have simpler internals and significantly improved
performance and UX. Commands and specialized APIs are no longer
necessary to keep everything in sync. Just spawn entities with the
relationship components you want and everything "just works".
2. Relationships are generalized. Bevy can provide additional built in
relationships, and users can define their own.
**REQUEST TO REVIEWERS**: _please don't leave top level comments and
instead comment on specific lines of code. That way we can take
advantage of threaded discussions. Also dont leave comments simply
pointing out CI failures as I can read those just fine._
## Built on top of what we have
Relationships are implemented on top of the Bevy ECS features we already
have: components, immutability, and hooks. This makes them immediately
compatible with all of our existing (and future) APIs for querying,
spawning, removing, scenes, reflection, etc. The fewer specialized APIs
we need to build, maintain, and teach, the better.
## Why focus on one-to-many non-fragmenting first?
1. This allows us to improve Parent/Children relationships immediately,
in a way that is reasonably uncontroversial. Switching our hierarchy to
fragmenting relationships would have significant performance
implications. ~~Flecs is heavily considering a switch to non-fragmenting
relations after careful considerations of the performance tradeoffs.~~
_(Correction from @SanderMertens: Flecs is implementing non-fragmenting
storage specialized for asset hierarchies, where asset hierarchies are
many instances of small trees that have a well defined structure)_
2. Adding generalized one-to-many relationships is currently a priority
for the [Next Generation Scene / UI
effort](https://github.com/bevyengine/bevy/discussions/14437).
Specifically, we're interested in building reactions and observers on
top.
## The changes
This PR does the following:
1. Adds a generic one-to-many Relationship system
3. Ports the existing Parent/Children system to Relationships, which now
lives in `bevy_ecs::hierarchy`. The old `bevy_hierarchy` crate has been
removed.
4. Adds on_despawn component hooks
5. Relationships can opt-in to "despawn descendants" behavior, meaning
that the entire relationship hierarchy is despawned when
`entity.despawn()` is called. The built in Parent/Children hierarchies
enable this behavior, and `entity.despawn_recursive()` has been removed.
6. `world.spawn` now applies commands after spawning. This ensures that
relationship bookkeeping happens immediately and removes the need to
manually flush. This is in line with the equivalent behaviors recently
added to the other APIs (ex: insert).
7. Removes the ValidParentCheckPlugin (system-driven / poll based) in
favor of a `validate_parent_has_component` hook.
## Using Relationships
The `Relationship` trait looks like this:
```rust
pub trait Relationship: Component + Sized {
type RelationshipSources: RelationshipSources<Relationship = Self>;
fn get(&self) -> Entity;
fn from(entity: Entity) -> Self;
}
```
A relationship is a component that:
1. Is a simple wrapper over a "target" Entity.
2. Has a corresponding `RelationshipSources` component, which is a
simple wrapper over a collection of entities. Every "target entity"
targeted by a "source entity" with a `Relationship` has a
`RelationshipSources` component, which contains every "source entity"
that targets it.
For example, the `Parent` component (as it currently exists in Bevy) is
the `Relationship` component and the entity containing the Parent is the
"source entity". The entity _inside_ the `Parent(Entity)` component is
the "target entity". And that target entity has a `Children` component
(which implements `RelationshipSources`).
In practice, the Parent/Children relationship looks like this:
```rust
#[derive(Relationship)]
#[relationship(relationship_sources = Children)]
pub struct Parent(pub Entity);
#[derive(RelationshipSources)]
#[relationship_sources(relationship = Parent)]
pub struct Children(Vec<Entity>);
```
The Relationship and RelationshipSources derives automatically implement
Component with the relevant configuration (namely, the hooks necessary
to keep everything in sync).
The most direct way to add relationships is to spawn entities with
relationship components:
```rust
let a = world.spawn_empty().id();
let b = world.spawn(Parent(a)).id();
assert_eq!(world.entity(a).get::<Children>().unwrap(), &[b]);
```
There are also convenience APIs for spawning more than one entity with
the same relationship:
```rust
world.spawn_empty().with_related::<Children>(|s| {
s.spawn_empty();
s.spawn_empty();
})
```
The existing `with_children` API is now a simpler wrapper over
`with_related`. This makes this change largely non-breaking for existing
spawn patterns.
```rust
world.spawn_empty().with_children(|s| {
s.spawn_empty();
s.spawn_empty();
})
```
There are also other relationship APIs, such as `add_related` and
`despawn_related`.
## Automatic recursive despawn via the new on_despawn hook
`RelationshipSources` can opt-in to "despawn descendants" behavior,
which will despawn all related entities in the relationship hierarchy:
```rust
#[derive(RelationshipSources)]
#[relationship_sources(relationship = Parent, despawn_descendants)]
pub struct Children(Vec<Entity>);
```
This means that `entity.despawn_recursive()` is no longer required.
Instead, just use `entity.despawn()` and the relevant related entities
will also be despawned.
To despawn an entity _without_ despawning its parent/child descendants,
you should remove the `Children` component first, which will also remove
the related `Parent` components:
```rust
entity
.remove::<Children>()
.despawn()
```
This builds on the on_despawn hook introduced in this PR, which is fired
when an entity is despawned (before other hooks).
## Relationships are the source of truth
`Relationship` is the _single_ source of truth component.
`RelationshipSources` is merely a reflection of what all the
`Relationship` components say. By embracing this, we are able to
significantly improve the performance of the system as a whole. We can
rely on component lifecycles to protect us against duplicates, rather
than needing to scan at runtime to ensure entities don't already exist
(which results in quadratic runtime). A single source of truth gives us
constant-time inserts. This does mean that we cannot directly spawn
populated `Children` components (or directly add or remove entities from
those components). I personally think this is a worthwhile tradeoff,
both because it makes the performance much better _and_ because it means
theres exactly one way to do things (which is a philosophy we try to
employ for Bevy APIs).
As an aside: treating both sides of the relationship as "equivalent
source of truth relations" does enable building simple and flexible
many-to-many relationships. But this introduces an _inherent_ need to
scan (or hash) to protect against duplicates.
[`evergreen_relations`](https://github.com/EvergreenNest/evergreen_relations)
has a very nice implementation of the "symmetrical many-to-many"
approach. Unfortunately I think the performance issues inherent to that
approach make it a poor choice for Bevy's default relationship system.
## Followup Work
* Discuss renaming `Parent` to `ChildOf`. I refrained from doing that in
this PR to keep the diff reasonable, but I'm personally biased toward
this change (and using that naming pattern generally for relationships).
* [Improved spawning
ergonomics](https://github.com/bevyengine/bevy/discussions/16920)
* Consider adding relationship observers/triggers for "relationship
targets" whenever a source is added or removed. This would replace the
current "hierarchy events" system, which is unused upstream but may have
existing users downstream. I think triggers are the better fit for this
than a buffered event queue, and would prefer not to add that back.
* Fragmenting relations: My current idea hinges on the introduction of
"value components" (aka: components whose type _and_ value determines
their ComponentId, via something like Hashing / PartialEq). By labeling
a Relationship component such as `ChildOf(Entity)` as a "value
component", `ChildOf(e1)` and `ChildOf(e2)` would be considered
"different components". This makes the transition between fragmenting
and non-fragmenting a single flag, and everything else continues to work
as expected.
* Many-to-many support
* Non-fragmenting: We can expand Relationship to be a list of entities
instead of a single entity. I have largely already written the code for
this.
* Fragmenting: With the "value component" impl mentioned above, we get
many-to-many support "for free", as it would allow inserting multiple
copies of a Relationship component with different target entities.
Fixes#3742 (If this PR is merged, I think we should open more targeted
followup issues for the work above, with a fresh tracking issue free of
the large amount of less-directed historical context)
Fixes#17301Fixes#12235Fixes#15299Fixes#15308
## Migration Guide
* Replace `ChildBuilder` with `ChildSpawnerCommands`.
* Replace calls to `.set_parent(parent_id)` with
`.insert(Parent(parent_id))`.
* Replace calls to `.replace_children()` with `.remove::<Children>()`
followed by `.add_children()`. Note that you'll need to manually despawn
any children that are not carried over.
* Replace calls to `.despawn_recursive()` with `.despawn()`.
* Replace calls to `.despawn_descendants()` with
`.despawn_related::<Children>()`.
* If you have any calls to `.despawn()` which depend on the children
being preserved, you'll need to remove the `Children` component first.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Many instances of `clippy::too_many_arguments` linting happen to be on
systems - functions which we don't call manually, and thus there's not
much reason to worry about the argument count.
## Solution
Allow `clippy::too_many_arguments` globally, and remove all lint
attributes related to it.
# Objective
- https://github.com/bevyengine/bevy/issues/17111
## Solution
Set the `clippy::allow_attributes` and
`clippy::allow_attributes_without_reason` lints to `deny`, and bring
`bevy_ui` in line with the new restrictions.
## Testing
`cargo clippy --tests` and `cargo test --package bevy_ui` were run, and
no errors were encountered.
# Objective
- Contributes to #11478
## Solution
- Made `bevy_utils::tracing` `doc(hidden)`
- Re-exported `tracing` from `bevy_log` for end-users
- Added `tracing` directly to crates that need it.
## Testing
- CI
---
## Migration Guide
If you were importing `tracing` via `bevy::utils::tracing`, instead use
`bevy::log::tracing`. Note that many items within `tracing` are also
directly re-exported from `bevy::log` as well, so you may only need
`bevy::log` for the most common items (e.g., `warn!`, `trace!`, etc.).
This also applies to the `log_once!` family of macros.
## Notes
- While this doesn't reduce the line-count in `bevy_utils`, it further
decouples the internal crates from `bevy_utils`, making its eventual
removal more feasible in the future.
- I have just imported `tracing` as we do for all dependencies. However,
a workspace dependency may be more appropriate for version management.
# Objective
- Fixes https://github.com/bevyengine/bevy/issues/16556
- Closes https://github.com/bevyengine/bevy/issues/11807
## Solution
- Simplify custom projections by using a single source of truth -
`Projection`, removing all existing generic systems and types.
- Existing perspective and orthographic structs are no longer components
- I could dissolve these to simplify further, but keeping them around
was the fast way to implement this.
- Instead of generics, introduce a third variant, with a trait object.
- Do an object safety dance with an intermediate trait to allow cloning
boxed camera projections. This is a normal rust polymorphism papercut.
You can do this with a crate but a manual impl is short and sweet.
## Testing
- Added a custom projection example
---
## Showcase
- Custom projections and projection handling has been simplified.
- Projection systems are no longer generic, with the potential for many
different projection components on the same camera.
- Instead `Projection` is now the single source of truth for camera
projections, and is the only projection component.
- Custom projections are still supported, and can be constructed with
`Projection::custom()`.
## Migration Guide
- `PerspectiveProjection` and `OrthographicProjection` are no longer
components. Use `Projection` instead.
- Custom projections should no longer be inserted as a component.
Instead, simply set the custom projection as a value of `Projection`
with `Projection::custom()`.
# Objective
Fixes#16104
## Solution
I removed all instances of `:?` and put them back one by one where it
caused an error.
I removed some bevy_utils helper functions that were only used in 2
places and don't add value. See: #11478
## Testing
CI should catch the mistakes
## Migration Guide
`bevy::utils::{dbg,info,warn,error}` were removed. Use
`bevy::utils::tracing::{debug,info,warn,error}` instead.
---------
Co-authored-by: SpecificProtagonist <vincentjunge@posteo.net>
# Objective
Some types like `RenderEntity` and `MainEntity` are just wrappers around
`Entity`, so they should be able to implement
`EntityBorrow`/`TrustedEntityBorrow`. This allows using them with
`EntitySet` functionality.
The `EntityRef` family are more than direct wrappers around `Entity`,
but can still benefit from being unique in a collection.
## Solution
Implement `EntityBorrow` and `TrustedEntityBorrow` for simple `Entity`
newtypes and `EntityRef` types.
These impls are an explicit decision to have the `EntityRef` types
compare like just `Entity`.
`EntityWorldMut` is omitted from this impl, because it explicitly
contains a `&mut World` as well, and we do not ever use more than one at
a time.
Add `EntityBorrow` to the `bevy_ecs` prelude.
## Migration Guide
`NormalizedWindowRef::entity` has been replaced with an
`EntityBorrow::entity` impl.
# Objective
Allow users to enable or disable layout rounding for specific UI nodes
and their descendants.
Fixes#16731
## Solution
New component `LayoutConfig` that can be added to any UiNode entity.
Setting the `use_rounding` field of `LayoutConfig` determines if the
Node and its descendants should be given rounded or unrounded
coordinates.
## Testing
Not tested this extensively but it seems to work and it's not very
complicated.
This really basic test app returns fractional coords:
```rust
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, report)
.run();
}
fn setup(mut commands: Commands) {
commands.spawn(Camera2d);
commands.spawn((
Node {
left: Val::Px(0.1),
width: Val::Px(100.1),
height: Val::Px(100.1),
..Default::default()
},
LayoutConfig { use_rounding: false },
));
}
fn report(node: Query<(Ref<ComputedNode>, &GlobalTransform)>) {
for (c, g) in node.iter() {
if c.is_changed() {
println!("{:#?}", c);
println!("position = {:?}", g.to_scale_rotation_translation().2);
}
}
}
```
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: UkoeHB <37489173+UkoeHB@users.noreply.github.com>
# Objective
- Enable modifying node size after layout.
- Gain access to a node's content_size. `UiSurface` is a private type so
content size can't be looked up.
## Solution
- Make `ComputedNode` fields public.
- Add `content_size` to `ComputedNode`.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
Scroll position uses physical coordinates. This means scrolling may go
faster or slower depending on the scroll factor. Also the scrolled
position will change when the scale factor changes.
## Solution
In `ui_layout_system` convert `max_possible_offset` to logical
coordinates before clamping the scroll position. Then convert the
clamped scroll position to physical coordinates before propagating it to
the node's children.
## Testing
Look at the `scroll` example. On main if you change your display's scale
factor the items displayed by the scrolling lists will change because
`ScrollPosition`'s displacement values don't respect scale factor. With
this PR the displacement will be scaled too, and the won't move.
Updating dependencies; adopted version of #15696. (Supercedes #15696.)
Long answer: hashbrown is no longer using ahash by default, meaning that
we can't use the default-hasher methods with ahasher. So, we have to use
the longer-winded versions instead. This takes the opportunity to also
switch our default hasher as well, but without actually enabling the
default-hasher feature for hashbrown, meaning that we'll be able to
change our hasher more easily at the cost of all of these method calls
being obnoxious forever.
One large change from 0.15 is that `insert_unique_unchecked` is now
`unsafe`, and for cases where unsafe code was denied at the crate level,
I replaced it with `insert`.
## Migration Guide
`bevy_utils` has updated its version of `hashbrown` to 0.15 and now
defaults to `foldhash` instead of `ahash`. This means that if you've
hard-coded your hasher to `bevy_utils::AHasher` or separately used the
`ahash` crate in your code, you may need to switch to `foldhash` to
ensure that everything works like it does in Bevy.
# Objective
- Fixes#16497
- This is my first PR, so I'm still learning to contribute to the
project
## Solution
- Added struct `UnregisterSystemCached` and function
`unregister_system_cached`
- renamed `World::run_system_with_input` to `run_system_with`
- reordered input parameters for `World::run_system_once_with`
## Testing
- Added a crude test which registers a system via
`World::register_system_cached`, and removes it via
`Command::unregister_system_cached`.
## Migration Guide
- Change all occurrences of `World::run_system_with_input` to
`World::run_system_with`.
- swap the order of input parameters for `World::run_system_once_with`
such that the system comes before the input.
---------
Co-authored-by: Paul Mattern <mail@paulmattern.dev>
# Objective
Fixes typos in bevy project, following suggestion in
https://github.com/bevyengine/bevy-website/pull/1912#pullrequestreview-2483499337
## Solution
I used https://github.com/crate-ci/typos to find them.
I included only the ones that feel undebatable too me, but I am not in
game engine so maybe some terms are expected.
I left out the following typos:
- `reparametrize` => `reparameterize`: There are a lot of occurences, I
believe this was expected
- `semicircles` => `hemicircles`: 2 occurences, may mean something
specific in geometry
- `invertation` => `inversion`: may mean something specific
- `unparented` => `parentless`: may mean something specific
- `metalness` => `metallicity`: may mean something specific
## Testing
- Did you test these changes? If so, how? I did not test the changes,
most changes are related to raw text. I expect the others to be tested
by the CI.
- Are there any parts that need more testing? I do not think
- How can other people (reviewers) test your changes? Is there anything
specific they need to know? To me there is nothing to test
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
---
## Migration Guide
> This section is optional. If there are no breaking changes, you can
delete this section.
(kept in case I include the `reparameterize` change here)
- If this PR is a breaking change (relative to the last release of
Bevy), describe how a user might need to migrate their code to support
these changes
- Simply adding new functionality is not a breaking change.
- Fixing behavior that was definitely a bug, rather than a questionable
design choice is not a breaking change.
## Questions
- [x] Should I include the above typos? No
(https://github.com/bevyengine/bevy/pull/16702#issuecomment-2525271152)
- [ ] Should I add `typos` to the CI? (I will check how to configure it
properly)
This project looks awesome, I really enjoy reading the progress made,
thanks to everyone involved.
# Objective
- Remove `derive_more`'s error derivation and replace it with
`thiserror`
## Solution
- Added `derive_more`'s `error` feature to `deny.toml` to prevent it
sneaking back in.
- Reverted to `thiserror` error derivation
## Notes
Merge conflicts were too numerous to revert the individual changes, so
this reversion was done manually. Please scrutinise carefully during
review.
# Objective
- Required by #16622 due to differing implementations of `System` by
`FunctionSystem` and `ExclusiveFunctionSystem`.
- Optimize the memory usage of instances of `apply_deferred` in system
schedules.
## Solution
By changing `apply_deferred` from being an ordinary system that ends up
as an `ExclusiveFunctionSystem`, and instead into a ZST struct that
implements `System` manually, we save ~320 bytes per instance of
`apply_deferred` in any schedule.
## Testing
- All current tests pass.
---
## Migration Guide
- If you were previously calling the special `apply_deferred` system via
`apply_deferred(world)`, don't.
# Objective
Remove the `min` and `max` fields from `LayoutContext`.
It doesn't seem useful to cache these values, it's simpler just to call
`min_element` and `max_element` on the `physical_size`
field.
## Migration Guide
The `min` and `max` fields have been removed from `LayoutContext`. To
retrieve these values call `min_element` and `max_element` on
`LayoutContent::physical_size` instead.
# Objective
- Keep Taffy version up to date
Taffy 0.6 doesn't include a huge amount relevant to Bevy. But it does:
- Add the `box_sizing` style
- Expose the computed `margin` in layout
- Traitifies the `Style` struct, which opens up the possibility of using
Bevy's `Style` struct directly (although Bevy currently does some style
resolution at conversion time which would no longer be cached if it was
used directly).
- Have a few bug fixes in the layout algorithms
## Solution
- Upgrade Taffy to `0.6.0`
## Testing
- I've run the `grid` example. All looks good.
- More testing is probably warranted. We have had regressions from Taffy
upgrades before
- Having said that, most of the algorithm changes this cycle were driven
by fixing WPT tests run through the new Servo integration. So they're
possibly less likely than usual to cause regressions.
## Breaking changes
The only "breaking" change is adding a field to `Style`. Probably
doesn't bear mentioning?
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
We switch back and forwards between logical and physical coordinates all
over the place. Systems have to query for cameras and the UiScale when
they shouldn't need to. It's confusing and fragile and new scale factor
bugs get found constantly.
## Solution
* Use physical coordinates whereever possible in `bevy_ui`.
* Store physical coords in `ComputedNode` and tear out all the unneeded
scale factor calculations and queries.
* Add an `inverse_scale_factor` field to `ComputedNode` and set nodes
changed when their scale factor changes.
## Migration Guide
`ComputedNode`'s fields and methods now use physical coordinates.
`ComputedNode` has a new field `inverse_scale_factor`. Multiplying the
physical coordinates by the `inverse_scale_factor` will give the logical
values.
---------
Co-authored-by: atlv <email@atlasdostal.com>
# Objective
- Fix bug where `UiSurface::set_camera_children` (and
`UiSurface::update_children` sometimes) will panic if you remove and add
a `Node` component in a single tick. This is more likely to happen now
because of `remove_with_requires`.
## Solution
- Filter out entities with `Node` when cleaning up entities from
`RemovedComponents<Node>`.
## Testing
- Not tested (rust compiler refused to cooperate when I tried to patch
this into my project), correct by inspection.
# Objective
Fixes#15940
## Solution
Remove the `pub use` and fix the compile errors.
Make `bevy_image` available as `bevy::image`.
## Testing
Feature Frenzy would be good here! Maybe I'll learn how to use it if I
have some time this weekend, or maybe a reviewer can use it.
## Migration Guide
Use `bevy_image` instead of `bevy_render::texture` items.
---------
Co-authored-by: chompaa <antony.m.3012@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
1. UI texture slicing chops and scales an image to fit the size of a
node and isn't meant to place any constraints on the size of the node
itself, but because the required components changes required `ImageSize`
and `ContentSize` for nodes with `UiImage`, texture sliced nodes are
laid out using an `ImageMeasure`.
2. In 0.14 users could spawn a `(UiImage, NodeBundle)` which would
display an image stretched to fill the UI node's bounds ignoring the
image's instrinsic size. Now that `UiImage` requires `ContentSize`,
there's no option to display an image without its size placing
constrains on the UI layout (unless you force the `Node` to a fixed
size, but that's not a solution).
3. It's desirable that the `Sprite` and `UiImage` share similar APIs.
Fixes#16109
## Solution
* Remove the `Component` impl from `ImageScaleMode`.
* Add a `Stretch` variant to `ImageScaleMode`.
* Add a field `scale_mode: ImageScaleMode` to `Sprite`.
* Add a field `mode: UiImageMode` to `UiImage`.
* Add an enum `UiImageMode` similar to `ImageScaleMode` but with
additional UI specific variants.
* Remove the queries for `ImageScaleMode` from Sprite and UI extraction,
and refer to the new fields instead.
* Change `ui_layout_system` to update measure funcs on any change to
`ContentSize`s to enable manual clearing without removing the component.
* Don't add a measure unless `UiImageMode::Auto` is set in
`update_image_content_size_system`. Mutably deref the `Mut<ContentSize>`
if the `UiImage` is changed to force removal of any existing measure
func.
## Testing
Remove all the constraints from the ui_texture_slice example:
```rust
//! This example illustrates how to create buttons with their textures sliced
//! and kept in proportion instead of being stretched by the button dimensions
use bevy::{
color::palettes::css::{GOLD, ORANGE},
prelude::*,
winit::WinitSettings,
};
fn main() {
App::new()
.add_plugins(DefaultPlugins)
// Only run the app when there is user input. This will significantly reduce CPU/GPU use.
.insert_resource(WinitSettings::desktop_app())
.add_systems(Startup, setup)
.add_systems(Update, button_system)
.run();
}
fn button_system(
mut interaction_query: Query<
(&Interaction, &Children, &mut UiImage),
(Changed<Interaction>, With<Button>),
>,
mut text_query: Query<&mut Text>,
) {
for (interaction, children, mut image) in &mut interaction_query {
let mut text = text_query.get_mut(children[0]).unwrap();
match *interaction {
Interaction::Pressed => {
**text = "Press".to_string();
image.color = GOLD.into();
}
Interaction::Hovered => {
**text = "Hover".to_string();
image.color = ORANGE.into();
}
Interaction::None => {
**text = "Button".to_string();
image.color = Color::WHITE;
}
}
}
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
let image = asset_server.load("textures/fantasy_ui_borders/panel-border-010.png");
let slicer = TextureSlicer {
border: BorderRect::square(22.0),
center_scale_mode: SliceScaleMode::Stretch,
sides_scale_mode: SliceScaleMode::Stretch,
max_corner_scale: 1.0,
};
// ui camera
commands.spawn(Camera2d);
commands
.spawn(Node {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
align_items: AlignItems::Center,
justify_content: JustifyContent::Center,
..default()
})
.with_children(|parent| {
for [w, h] in [[150.0, 150.0], [300.0, 150.0], [150.0, 300.0]] {
parent
.spawn((
Button,
Node {
// width: Val::Px(w),
// height: Val::Px(h),
// horizontally center child text
justify_content: JustifyContent::Center,
// vertically center child text
align_items: AlignItems::Center,
margin: UiRect::all(Val::Px(20.0)),
..default()
},
UiImage::new(image.clone()),
ImageScaleMode::Sliced(slicer.clone()),
))
.with_children(|parent| {
// parent.spawn((
// Text::new("Button"),
// TextFont {
// font: asset_server.load("fonts/FiraSans-Bold.ttf"),
// font_size: 33.0,
// ..default()
// },
// TextColor(Color::srgb(0.9, 0.9, 0.9)),
// ));
});
}
});
}
```
This should result in a blank window, since without any constraints the
texture slice image nodes should be zero-sized. But in main the image
nodes are given the size of the underlying unsliced source image
`textures/fantasy_ui_borders/panel-border-010.png`:
<img width="321" alt="slicing"
src="https://github.com/user-attachments/assets/cbd74c9c-14cd-4b4d-93c6-7c0152bb05ee">
For this PR need to change the lines:
```
UiImage::new(image.clone()),
ImageScaleMode::Sliced(slicer.clone()),
```
to
```
UiImage::new(image.clone()).with_mode(UiImageMode::Sliced(slicer.clone()),
```
and then nothing should be rendered, as desired.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Taffy added layout rounding a while ago but it had a couple of bugs and
caused some problems with the fussy `ab_glyph` text implementation. So I
disabled Taffy's builtin rounding and added some hacks ad hoc that fixed
(some) of those issues. Since then though Taffy's rounding algorithm has
improved while we've changed layout a lot and migrated to `cosmic-text`
so those hacks don't help any more and in some cases cause significant
problems.
Also our rounding implementation only rounds to the nearest logical
pixel, whereas Taffy rounds to the nearest physical pixel meaning it's
much more accurate with high dpi displays.
fixes#15197
## Some examples of layout rounding errors visible in the UI examples
These errors are much more obvious at high scale factor, you might not
see any problems at a scale factor of 1.
`cargo run --example text_wrap_debug`
<img width="1000" alt="text_debug_gaps"
src="https://github.com/user-attachments/assets/5a584016-b8e2-487b-8842-f0f359077391">
The narrow horizontal and vertical lines are gaps in the layout caused
by errors in the coordinate rounding.
`cargo run --example text_debug`
<img width="1000" alt="text_debug"
src="https://github.com/user-attachments/assets/a4b37c02-a2fd-441c-a7bd-cd7a1a72e7dd">
The two text blocks here are aligned right to the same boundary but in
this screen shot you can see that the lower block is one pixel off to
the left. Because the size of this text node changes between frames with
the reported framerate the rounding errors cause it to jump left and
right.
## Solution
Remove all our custom rounding hacks and reenable Taffy's layout
rounding.
The gaps in the `text_wrap_debug` example are gone:
<img width="1000" alt="text_wrap_debug_fix"
src="https://github.com/user-attachments/assets/92d2dd97-30c6-4ac8-99f1-6d65358995a7">
This doesn't fix some of the gaps that occur between borders and content
but they seem appear to be a rendering problem as they disappear with
`UiAntiAlias::Off` set.
## Testing
Run the examples as described above in the `Objective` section. With
this PR the problems mentioned shouldn't appear.
Also added an example in a separate PR #16096 `layout_rounding_debug`
for identifying these issues.
## Migration Guide
`UiSurface::get_layout` now also returns the final sizes before
rounding. Call `.0` on the `Ok` result to get the previously returned
`taffy::Layout` value.
---------
Co-authored-by: Rob Parrett <robparrett@gmail.com>
# Objective
Remove `calculated_` from the name `ComputedNode::calculated_size` as
redundant, It's obvious from context that it's the resolved size value
and it's inconsistant since none of other fields of `ComputedNode` have
a `calculated_` prefix.
## Alternatives
Rename all the fields of `ComputedNode` to `calculated_*`, this seems
worse.
# Objective
Fixes#16006
## Solution
We currently re-export `cosmic_text`, which is seemingly motivated by
the desire to use `cosmic_text::FontSystem` in `bevy_text` public APIs
instead of our `CosmicFontSystem` resource wrapper type.
This change makes `bevy_text` a "true" abstraction over `cosmic_text`
(it in fact, was already built to be that way generally and has this one
"leak").
This allows us to remove the `cosmic_text` re-export, which helps clean
up the Rust Analyzer imports and generally makes this a "cleaner" API.
# Objective
Continue improving the user experience of our UI Node API in the
direction specified by [Bevy's Next Generation Scene / UI
System](https://github.com/bevyengine/bevy/discussions/14437)
## Solution
As specified in the document above, merge `Style` fields into `Node`,
and move "computed Node fields" into `ComputedNode` (I chose this name
over something like `ComputedNodeLayout` because it currently contains
more than just layout info. If we want to break this up / rename these
concepts, lets do that in a separate PR). `Style` has been removed.
This accomplishes a number of goals:
## Ergonomics wins
Specifying both `Node` and `Style` is now no longer required for
non-default styles
Before:
```rust
commands.spawn((
Node::default(),
Style {
width: Val::Px(100.),
..default()
},
));
```
After:
```rust
commands.spawn(Node {
width: Val::Px(100.),
..default()
});
```
## Conceptual clarity
`Style` was never a comprehensive "style sheet". It only defined "core"
style properties that all `Nodes` shared. Any "styled property" that
couldn't fit that mold had to be in a separate component. A "real" style
system would style properties _across_ components (`Node`, `Button`,
etc). We have plans to build a true style system (see the doc linked
above).
By moving the `Style` fields to `Node`, we fully embrace `Node` as the
driving concept and remove the "style system" confusion.
## Next Steps
* Consider identifying and splitting out "style properties that aren't
core to Node". This should not happen for Bevy 0.15.
---
## Migration Guide
Move any fields set on `Style` into `Node` and replace all `Style`
component usage with `Node`.
Before:
```rust
commands.spawn((
Node::default(),
Style {
width: Val::Px(100.),
..default()
},
));
```
After:
```rust
commands.spawn(Node {
width: Val::Px(100.),
..default()
});
```
For any usage of the "computed node properties" that used to live on
`Node`, use `ComputedNode` instead:
Before:
```rust
fn system(nodes: Query<&Node>) {
for node in &nodes {
let computed_size = node.size();
}
}
```
After:
```rust
fn system(computed_nodes: Query<&ComputedNode>) {
for computed_node in &computed_nodes {
let computed_size = computed_node.size();
}
}
```
