Commit graph

230 commits

Author SHA1 Message Date
Lynn
887bc27a6f
Animatable for colors (#12614)
# Objective

- Fixes #12202 

## Solution

- Implements `Animatable` for all color types implementing arithmetic
operations.
  - the colors returned by `Animatable`s methods are already clamped.
- Adds a `color_animation.rs` example.
- Implements the `*Assign` operators for color types that already had
the corresponding operators. This is just a 'nice to have' and I am
happy to remove this if it's not wanted.

---

## Changelog

- `bevy_animation` now depends on `bevy_color`.
- `LinearRgba`, `Laba`, `Oklaba` and `Xyza` implement `Animatable`.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
2024-03-22 00:06:24 +00:00
Antony
e7a31d000e
Add border radius to UI nodes (adopted) (#12500)
# Objective

Implements border radius for UI nodes. Adopted from #8973, but excludes
shadows.

## Solution

- Add a component `BorderRadius` which contains a radius value for each
corner of the UI node.
- Use a fragment shader to generate the rounded corners using a signed
distance function.

<img width="50%"
src="https://github.com/bevyengine/bevy/assets/26204416/16b2ba95-e274-4ce7-adb2-34cc41a776a5"></img>

## Changelog

- `BorderRadius`: New component that holds the border radius values.
- `NodeBundle` & `ButtonBundle`: Added a `border_radius: BorderRadius`
field.
- `extract_uinode_borders`: Stripped down, most of the work is done in
the shader now. Borders are no longer assembled from multiple rects,
instead the shader uses a signed distance function to draw the border.
- `UiVertex`: Added size, border and radius fields.
- `UiPipeline`: Added three vertex attributes to the vertex buffer
layout, to accept the UI node's size, border thickness and border
radius.
- Examples: Added rounded corners to the UI element in the `button`
example, and a `rounded_borders` example.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
Co-authored-by: Pablo Reinhardt <126117294+pablo-lua@users.noreply.github.com>
2024-03-19 22:44:00 +00:00
Matty
325f0fd982
Alignment API for Transforms (#12187)
# Objective

- Closes #11793 
- Introduces a general API for aligning local coordinates of Transforms
with given vectors.

## Solution

- We introduce `Transform::align`, which allows a rotation to be
specified by four pieces of alignment data, as explained by the
documentation:
````rust
/// Rotates this [`Transform`] so that the `main_axis` vector, reinterpreted in local coordinates, points
/// in the given `main_direction`, while `secondary_axis` points towards `secondary_direction`.
///
/// For example, if a spaceship model has its nose pointing in the X-direction in its own local coordinates
/// and its dorsal fin pointing in the Y-direction, then `align(Vec3::X, v, Vec3::Y, w)` will make the spaceship's
/// nose point in the direction of `v`, while the dorsal fin does its best to point in the direction `w`.
///
/// More precisely, the [`Transform::rotation`] produced will be such that:
/// * applying it to `main_axis` results in `main_direction`
/// * applying it to `secondary_axis` produces a vector that lies in the half-plane generated by `main_direction` and
/// `secondary_direction` (with positive contribution by `secondary_direction`)
///
/// [`Transform::look_to`] is recovered, for instance, when `main_axis` is `Vec3::NEG_Z` (the [`Transform::forward`]
/// direction in the default orientation) and `secondary_axis` is `Vec3::Y` (the [`Transform::up`] direction in the default
/// orientation). (Failure cases may differ somewhat.)
///
/// In some cases a rotation cannot be constructed. Another axis will be picked in those cases:
/// * if `main_axis` or `main_direction` is zero, `Vec3::X` takes its place
/// * if `secondary_axis` or `secondary_direction` is zero, `Vec3::Y` takes its place
/// * if `main_axis` is parallel with `secondary_axis` or `main_direction` is parallel with `secondary_direction`,
/// a rotation is constructed which takes `main_axis` to `main_direction` along a great circle, ignoring the secondary
/// counterparts
/// 
/// Example
/// ```
/// # use bevy_math::{Vec3, Quat};
/// # use bevy_transform::components::Transform;
/// let mut t1 = Transform::IDENTITY;
/// let mut t2 = Transform::IDENTITY;
/// t1.align(Vec3::ZERO, Vec3::Z, Vec3::ZERO, Vec3::X);
/// t2.align(Vec3::X, Vec3::Z, Vec3::Y, Vec3::X);
/// assert_eq!(t1.rotation, t2.rotation);
/// 
/// t1.align(Vec3::X, Vec3::Z, Vec3::X, Vec3::Y);
/// assert_eq!(t1.rotation, Quat::from_rotation_arc(Vec3::X, Vec3::Z));
/// ```
pub fn align(
    &mut self,
    main_axis: Vec3,
    main_direction: Vec3,
    secondary_axis: Vec3,
    secondary_direction: Vec3,
) { //... }
````

- We introduce `Transform::aligned_by`, the returning-Self version of
`align`:
````rust
pub fn aligned_by(
    mut self,
    main_axis: Vec3,
    main_direction: Vec3,
    secondary_axis: Vec3,
    secondary_direction: Vec3,
) -> Self { //... }
````

- We introduce an example (examples/transforms/align.rs) that shows the
usage of this API. It is likely to be mathier than most other
`Transform` APIs, so when run, the example demonstrates what the API
does in space:
<img width="1440" alt="Screenshot 2024-03-12 at 11 01 19 AM"
src="https://github.com/bevyengine/bevy/assets/2975848/884b3cc3-cbd9-48ae-8f8c-49a677c59dfe">

---

## Changelog

- Added methods `align`, `aligned_by` to `Transform`.
- Added transforms/align.rs to examples.

---

## Discussion

### On the form of `align`

The original issue linked above suggests an API similar to that of the
existing `Transform::look_to` method:
````rust
pub fn align_to(&mut self, direction: Vec3, up: Vec3) { //... }
````
Not allowing an input axis of some sort that is to be aligned with
`direction` would not really solve the problem in the issue, since the
user could easily be in a scenario where they have to compose with
another rotation on their own (undesirable). This leads to something
like:
````rust
pub fn align_to(&mut self, axis: Vec3, direction: Vec3, up: Vec3) { //... }
````
However, this still has two problems:
- If the vector that the user wants to align is parallel to the Y-axis,
then the API basically does not work (we cannot fully specify a
rotation)
- More generally, it does not give the user the freedom to specify which
direction is to be treated as the local "up" direction, so it fails as a
general alignment API

Specifying both leads us to the present situation, with two local axis
inputs (`main_axis` and `secondary_axis`) and two target directions
(`main_direction` and `secondary_direction`). This might seem a little
cumbersome for general use, but for the time being I stand by the
decision not to expand further without prompting from users. I'll expand
on this below.

### Additional APIs?

Presently, this PR introduces only `align` and `aligned_by`. Other
potentially useful bundles of API surface arrange into a few different
categories:

1. Inferring direction from position, a la `Transform::look_at`, which
might look something like this:
````rust
pub fn align_at(&mut self, axis: Vec3, target: Vec3, up: Vec3) {
    self.align(axis, target - self.translation, Vec3::Y, up);
}
````
(This is simple but still runs into issues when the user wants to point
the local Y-axis somewhere.)

2. Filling in some data for the user for common use-cases; e.g.:
````rust
pub fn align_x(&mut self, direction: Vec3, up: Vec3) {
    self.align(Vec3::X, direction, Vec3::Y, up);
}
````
(Here, use of the `up` vector doesn't lose any generality, but it might
be less convenient to specify than something else. This does naturally
leave open the question of what `align_y` would look like if we provided
it.)

Morally speaking, I do think that the `up` business is more pertinent
when the intention is to work with cameras, which the `look_at` and
`look_to` APIs seem to cover pretty well. If that's the case, then I'm
not sure what the ideal shape for these API functions would be, since it
seems like a lot of input would have to be baked into the function
definitions. For some cases, this might not be the end of the world:
````rust
pub fn align_x_z(&mut self, direction: Vec3, weak_direction: Vec3) {
    self.align(Vec3::X, direction, Vec3::Z, weak_direction);
}
````
(However, this is not symmetrical in x and z, so you'd still need six
API functions just to support the standard positive coordinate axes, and
if you support negative axes then things really start to balloon.)

The reasons that these are not actually produced in this PR are as
follows:
1. Without prompting from actual users in the wild, it is unknown to me
whether these additional APIs would actually see a lot of use. Extending
these to our users in the future would be trivial if we see there is a
demand for something specific from the above-mentioned categories.
2. As discussed above, there are so many permutations of these that
could be provided that trying to do so looks like it risks unduly
ballooning the API surface for this feature.
3. Finally, and most importantly, creating these helper functions in
user-space is trivial, since they all just involve specializing `align`
to particular inputs; e.g.:
````rust
fn align_ship(ship_transform: &mut Transform, nose_direction: Vec3, dorsal_direction: Vec3) {
    ship_transform.align(Ship::NOSE, nose_direction, Ship::DORSAL, dorsal_direction);
}
````

With that in mind, I would prefer instead to focus on making the
documentation and examples for a thin API as clear as possible, so that
users can get a grip on the tool and specialize it for their own needs
when they feel the desire to do so.

### `Dir3`?

As in the case of `Transform::look_to` and `Transform::look_at`, the
inputs to this function are, morally speaking, *directions* rather than
vectors (actually, if we're being pedantic, the input is *really really*
a pair of orthonormal frames), so it's worth asking whether we should
really be using `Dir3` as inputs instead of `Vec3`. I opted for `Vec3`
for the following reasons:
1. Specifying a `Dir3` in user-space is just more annoying than
providing a `Vec3`. Even in the most basic cases (e.g. providing a
vector literal), you still have to do error handling or call an unsafe
unwrap in your function invocations.
2. The existing API mentioned above uses `Vec3`, so we are just adhering
to the same thing.

Of course, the use of `Vec3` has its own downsides; it can be argued
that the replacement of zero-vectors with fixed ones (which we do in
`Transform::align` as well as `Transform::look_to`) more-or-less amounts
to failing silently.

### Future steps

The question of additional APIs was addressed above. For me, the main
thing here to handle more immediately is actually just upstreaming this
API (or something similar and slightly mathier) to `glam::Quat`. The
reason that this would be desirable for users is that this API currently
only works with `Transform`s even though all it's actually doing is
specifying a rotation. Upstreaming to `glam::Quat`, properly done, could
buy a lot basically for free, since a number of `Transform` methods take
a rotation as an input. Using these together would require a little bit
of mathematical savvy, but it opens up some good things (e.g.
`Transform::rotate_around`).
2024-03-14 14:55:55 +00:00
Mateusz Wachowiak
2d29954034
Fps overlay (#12382)
# Objective

- Part of #12351
- Add fps overlay

## Solution

- Create `FpsOverlayPlugin`
- Allow for configuration through resource `FpsOverlayConfig`
- Allow for configuration during runtime

### Preview on default settings

![20240308_22h23m25s_grim](https://github.com/bevyengine/bevy/assets/62356462/33d3d7a9-435e-4e0b-9814-d3274e779a69)

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-03-11 19:26:14 +00:00
Patrick Walton
dfdf2b9ea4
Implement the AnimationGraph, allowing for multiple animations to be blended together. (#11989)
This is an implementation of RFC #51:
https://github.com/bevyengine/rfcs/blob/main/rfcs/51-animation-composition.md

Note that the implementation strategy is different from the one outlined
in that RFC, because two-phase animation has now landed.

# Objective

Bevy needs animation blending. The RFC for this is [RFC 51].

## Solution

This is an implementation of the RFC. Note that the implementation
strategy is different from the one outlined there, because two-phase
animation has now landed.

This is just a draft to get the conversation started. Currently we're
missing a few things:

- [x] A fully-fleshed-out mechanism for transitions
- [x] A serialization format for `AnimationGraph`s
- [x] Examples are broken, other than `animated_fox`
- [x] Documentation

---

## Changelog

### Added

* The `AnimationPlayer` has been reworked to support blending multiple
animations together through an `AnimationGraph`, and as such will no
longer function unless a `Handle<AnimationGraph>` has been added to the
entity containing the player. See [RFC 51] for more details.

* Transition functionality has moved from the `AnimationPlayer` to a new
component, `AnimationTransitions`, which works in tandem with the
`AnimationGraph`.

## Migration Guide

* `AnimationPlayer`s can no longer play animations by themselves and
need to be paired with a `Handle<AnimationGraph>`. Code that was using
`AnimationPlayer` to play animations will need to create an
`AnimationGraph` asset first, add a node for the clip (or clips) you
want to play, and then supply the index of that node to the
`AnimationPlayer`'s `play` method.

* The `AnimationPlayer::play_with_transition()` method has been removed
and replaced with the `AnimationTransitions` component. If you were
previously using `AnimationPlayer::play_with_transition()`, add all
animations that you were playing to the `AnimationGraph`, and create an
`AnimationTransitions` component to manage the blending between them.

[RFC 51]:
https://github.com/bevyengine/rfcs/blob/main/rfcs/51-animation-composition.md

---------

Co-authored-by: Rob Parrett <robparrett@gmail.com>
2024-03-07 20:22:42 +00:00
Turki Al-Marri
6f2ecdf822
We must have googly eyes (new Game example) (#12331)
# Objective

- We must have googly eyes.
- Also it would be nice if there was an example of a desk toy
application (like the old NEKO.EXE).

## Solution

- Created an example with googly eyed Bevy logo under
examples/games/desktoy.rs.

---

## Changelog
- Added "Desk Toy" game example showcasing window transparency and hit
test.

---------

Co-authored-by: Rob Parrett <robparrett@gmail.com>
2024-03-06 22:21:41 +00:00
NiseVoid
e3b318f599
Add extra_asset_source example (#11824)
# Objective

- Make it easier to figure out how to add asset sources

## Solution

- Add an example that adds an asset source, it functions almost
identical to the embedded_asset example
- Move the file from the embedded_asset example into a `files/` folder
2024-03-06 16:00:03 +00:00
Félix Lescaudey de Maneville
fc202f2e3d
Slicing support for texture atlas (#12059)
# Objective

Follow up to #11600 and #10588 
https://github.com/bevyengine/bevy/issues/11944 made clear that some
people want to use slicing with texture atlases

## Changelog

* Added support for `TextureAtlas` slicing and tiling.
`SpriteSheetBundle` and `AtlasImageBundle` can now use `ImageScaleMode`
* Added new `ui_texture_atlas_slice` example using a texture sheet

<img width="798" alt="Screenshot 2024-02-23 at 11 58 35"
src="https://github.com/bevyengine/bevy/assets/26703856/47a8b764-127c-4a06-893f-181703777501">

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Pablo Reinhardt <126117294+pablo-lua@users.noreply.github.com>
2024-03-05 16:05:39 +00:00
Matty
4673fb3e57
Example for axes gizmos (#12299)
# Objective

- Follow-up to #12211 
- Introduces an example project that demonstrates the implementation and
behavior of `Gizmos::axes` for an entity with a `Transform` component.

## Solution

In order to demonstrate how `Gizmo::axes` can be used and behaves in
practice, we introduce an example of a simple scene containing a pair of
cuboids locked in a grotesque, inscrutable dance: the two are repeatedly
given random `Transform`s which they interpolate to, showing how the
axes move with objects as they translate, rotate, and scale.

<img width="1023" alt="Screenshot 2024-03-04 at 1 16 33 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/c1ff4794-6722-491c-8522-f59801645139">



On the implementation side, we demonstrate how to draw axes for
entities, automatically sizing them according to their bounding boxes
(so that the axes will be visible):
````rust
fn draw_axes(mut gizmos: Gizmos, query: Query<(&Transform, &Aabb), With<ShowAxes>>) {
    for (&transform, &aabb) in &query {
        let length = aabb.half_extents.length();
        gizmos.axes(transform, length);
    }
}
````

---

## Changelog

- Created examples/gizmos/axes.rs.
- Added 'axes' example to Cargo.toml.
2024-03-04 19:30:39 +00:00
Doonv
14c20a6c9c
Add access to App within LogPlugin::update_subscriber (#12045)
# Objective

In my library,
[`bevy_dev_console`](https://github.com/doonv/bevy_dev_console) I need
access to `App` within `LogPlugin::update_subscriber` in order to
communicate with the `App` from my custom `Layer`.

## Solution

Give access to `App`.

---

## Changelog

- Added access to `App` within `LogPlugin::update_subscriber`

## Migration Guide

`LogPlugin::update_subscriber` now has a `&mut App` parameter. If you
don't need access to `App`, you can ignore the parameter with an
underscore (`_`).

```diff,rust
- fn update_subscriber(subscriber: BoxedSubscriber) -> BoxedSubscriber {
+ fn update_subscriber(_: &mut App, subscriber: BoxedSubscriber) -> BoxedSubscriber {
      Box::new(subscriber.with(CustomLayer))
  }
```
2024-03-04 00:01:05 +00:00
Kanabenki
de0ed293fa
Add basic light gizmos (#12228)
# Objective

- Part of #9400.
- Add light gizmos for `SpotLight`, `PointLight` and `DirectionalLight`.

## Solution

- Add a `ShowLightGizmo` and its related gizmo group and plugin, that
shows a gizmo for all lights of an entities when inserted on it. Light
display can also be toggled globally through the gizmo config in the
same way it can already be done for `Aabb`s.
- Add distinct segment setters for height and base one `Cone3dBuilder`.
This allow having a properly rounded base without too much edges along
the height. The doc comments explain how to ensure height and base
connect when setting different values.

Gizmo for the three light types without radius with the depth bias set
to -1:

![without-radius](https://github.com/bevyengine/bevy/assets/18357657/699d0154-f367-4727-9b09-8b458d96a0e2)

With Radius:

![with-radius](https://github.com/bevyengine/bevy/assets/18357657/f3af003e-dbba-427a-a305-c5cc1676e340)

Possible future improvements:
- Add a billboarded sprite with a distinct sprite for each light type.
- Display the intensity of the light somehow (no idea how to represent
that apart from some text).

---

## Changelog

### Added

- The new `ShowLightGizmo`, part of the `LightGizmoPlugin` and
configurable globally with `LightGizmoConfigGroup`, allows drawing gizmo
for `PointLight`, `SpotLight` and `DirectionalLight`. The gizmos color
behavior can be controlled with the `LightGizmoColor` member of
`ShowLightGizmo` and `LightGizmoConfigGroup`.
- The cone gizmo builder (`Cone3dBuilder`) now allows setting a
differing number of segments for the base and height.

---------

Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
2024-03-03 18:50:46 +00:00
Kaur Kuut
165c360070
Update wgpu to v0.19.3 and unpin web-sys. (#12247)
# Objective

This PR unpins `web-sys` so that unrelated projects that have
`bevy_render` in their workspace can finally update their `web-sys`.
More details in and fixes #12246.

## Solution

* Update `wgpu` from 0.19.1 to 0.19.3.
* Remove the `web-sys` pin.
* Update docs and wasm helper to remove the now-stale
`--cfg=web_sys_unstable_apis` Rust flag.

---

## Changelog

Updated `wgpu` to v0.19.3 and removed `web-sys` pin.
2024-03-02 00:44:51 +00:00
James O'Brien
94ff123d7f
Component Lifecycle Hooks and a Deferred World (#10756)
# Objective

- Provide a reliable and performant mechanism to allows users to keep
components synchronized with external sources: closing/opening sockets,
updating indexes, debugging etc.
- Implement a generic mechanism to provide mutable access to the world
without allowing structural changes; this will not only be used here but
is a foundational piece for observers, which are key for a performant
implementation of relations.

## Solution

- Implement a new type `DeferredWorld` (naming is not important,
`StaticWorld` is also suitable) that wraps a world pointer and prevents
user code from making any structural changes to the ECS; spawning
entities, creating components, initializing resources etc.
- Add component lifecycle hooks `on_add`, `on_insert` and `on_remove`
that can be assigned callbacks in user code.

---

## Changelog
- Add new `DeferredWorld` type.
- Add new world methods: `register_component::<T>` and
`register_component_with_descriptor`. These differ from `init_component`
in that they provide mutable access to the created `ComponentInfo` but
will panic if the component is already in any archetypes. These
restrictions serve two purposes:
1. Prevent users from defining hooks for components that may already
have associated hooks provided in another plugin. (a use case better
served by observers)
2. Ensure that when an `Archetype` is created it gets the appropriate
flags to early-out when triggering hooks.
- Add methods to `ComponentInfo`: `on_add`, `on_insert` and `on_remove`
to be used to register hooks of the form `fn(DeferredWorld, Entity,
ComponentId)`
- Modify `BundleInserter`, `BundleSpawner` and `EntityWorldMut` to
trigger component hooks when appropriate.
- Add bit flags to `Archetype` indicating whether or not any contained
components have each type of hook, this can be expanded for other flags
as needed.
- Add `component_hooks` example to illustrate usage. Try it out! It's
fun to mash keys.

## Safety
The changes to component insertion, removal and deletion involve a large
amount of unsafe code and it's fair for that to raise some concern. I
have attempted to document it as clearly as possible and have confirmed
that all the hooks examples are accepted by `cargo miri` as not causing
any undefined behavior. The largest issue is in ensuring there are no
outstanding references when passing a `DeferredWorld` to the hooks which
requires some use of raw pointers (as was already happening to some
degree in those places) and I have taken some time to ensure that is the
case but feel free to let me know if I've missed anything.

## Performance
These changes come with a small but measurable performance cost of
between 1-5% on `add_remove` benchmarks and between 1-3% on `insert`
benchmarks. One consideration to be made is the existence of the current
`RemovedComponents` which is on average more costly than the addition of
`on_remove` hooks due to the early-out, however hooks doesn't completely
remove the need for `RemovedComponents` as there is a chance you want to
respond to the removal of a component that already has an `on_remove`
hook defined in another plugin, so I have not removed it here. I do
intend to deprecate it with the introduction of observers in a follow up
PR.

## Discussion Questions
- Currently `DeferredWorld` implements `Deref` to `&World` which makes
sense conceptually, however it does cause some issues with rust-analyzer
providing autocomplete for `&mut World` references which is annoying.
There are alternative implementations that may address this but involve
more code churn so I have attempted them here. The other alternative is
to not implement `Deref` at all but that leads to a large amount of API
duplication.
- `DeferredWorld`, `StaticWorld`, something else?
- In adding support for hooks to `EntityWorldMut` I encountered some
unfortunate difficulties with my desired API. If commands are flushed
after each call i.e. `world.spawn() // flush commands .insert(A) //
flush commands` the entity may be despawned while `EntityWorldMut` still
exists which is invalid. An alternative was then to add
`self.world.flush_commands()` to the drop implementation for
`EntityWorldMut` but that runs into other problems for implementing
functions like `into_unsafe_entity_cell`. For now I have implemented a
`.flush()` which will flush the commands and consume `EntityWorldMut` or
users can manually run `world.flush_commands()` after using
`EntityWorldMut`.
- In order to allowing querying on a deferred world we need
implementations of `WorldQuery` to not break our guarantees of no
structural changes through their `UnsafeWorldCell`. All our
implementations do this, but there isn't currently any safety
documentation specifying what is or isn't allowed for an implementation,
just for the caller, (they also shouldn't be aliasing components they
didn't specify access for etc.) is that something we should start doing?
(see 10752)

Please check out the example `component_hooks` or the tests in
`bundle.rs` for usage examples. I will continue to expand this
description as I go.

See #10839 for a more ergonomic API built on top of this one that isn't
subject to the same restrictions and supports `SystemParam` dependency
injection.
2024-03-01 14:59:22 +00:00
Joshua Schlichting
a463d0c637
Fixed iOS documentation typo for xcrun command (#12112)
```
$ xcrun simctl devices list
Unrecognized subcommand: devices
usage: simctl [--set <path>] [--profiles <path>] <subcommand> ...
       simctl help [subcommand]
Command line utility to control the Simulator
```

# Objective

- The `examples/README.md` contains an invalid example command for
listing iOS devices using `xcrun`.
## Solution

- Update example command to omit the current invalid subcommand
"`devices`".
2024-02-26 04:59:19 +00:00
Evgeny Kropotin
d3e839a8e5
Move gizmos examples in the separate folder (#11916)
# Objective

Move Gizmo examples into the separate directory

Fixes #11899

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Joona Aalto <jondolf.dev@gmail.com>
2024-02-21 20:16:25 +00:00
Robert Walter
b446374392
Dedicated primitive example (#11697)
I just implemented this to record a video for the new blog post, but I
figured it would also make a good dedicated example. This also allows us
to remove a lot of code from the 2d/3d gizmo examples since it
supersedes this portion of code.

Depends on: https://github.com/bevyengine/bevy/pull/11699
2024-02-14 16:55:44 +00:00
Félix Lescaudey de Maneville
ab16f5ed6a
UI Texture 9 slice (#11600)
> Follow up to #10588 
> Closes #11749 (Supersedes #11756)

Enable Texture slicing for the following UI nodes:
- `ImageBundle`
- `ButtonBundle`

<img width="739" alt="Screenshot 2024-01-29 at 13 57 43"
src="https://github.com/bevyengine/bevy/assets/26703856/37675681-74eb-4689-ab42-024310cf3134">

I also added a collection of `fantazy-ui-borders` from
[Kenney's](www.kenney.nl) assets, with the appropriate license (CC).
If it's a problem I can use the same textures as the `sprite_slice`
example

# Work done

Added the `ImageScaleMode` component to the targetted bundles, most of
the logic is directly reused from `bevy_sprite`.
The only additional internal component is the UI specific
`ComputedSlices`, which does the same thing as its spritee equivalent
but adapted to UI code.

Again the slicing is not compatible with `TextureAtlas`, it's something
I need to tackle more deeply in the future

# Fixes

* [x] I noticed that `TextureSlicer::compute_slices` could infinitely
loop if the border was larger that the image half extents, now an error
is triggered and the texture will fallback to being stretched
* [x] I noticed that when using small textures with very small *tiling*
options we could generate hundred of thousands of slices. Now I set a
minimum size of 1 pixel per slice, which is already ridiculously small,
and a warning will be sent at runtime when slice count goes above 1000
* [x] Sprite slicing with `flip_x` or `flip_y` would give incorrect
results, correct flipping is now supported to both sprites and ui image
nodes thanks to @odecay observation

# GPU Alternative

I create a separate branch attempting to implementing 9 slicing and
tiling directly through the `ui.wgsl` fragment shader. It works but
requires sending more data to the GPU:
- slice border
- tiling factors

And more importantly, the actual quad *scale* which is hard to put in
the shader with the current code, so that would be for a later iteration
2024-02-07 20:07:53 +00:00
Patrick Walton
4c15dd0fc5
Implement irradiance volumes. (#10268)
# Objective

Bevy could benefit from *irradiance volumes*, also known as *voxel
global illumination* or simply as light probes (though this term is not
preferred, as multiple techniques can be called light probes).
Irradiance volumes are a form of baked global illumination; they work by
sampling the light at the centers of each voxel within a cuboid. At
runtime, the voxels surrounding the fragment center are sampled and
interpolated to produce indirect diffuse illumination.

## Solution

This is divided into two sections. The first is copied and pasted from
the irradiance volume module documentation and describes the technique.
The second part consists of notes on the implementation.

### Overview

An *irradiance volume* is a cuboid voxel region consisting of
regularly-spaced precomputed samples of diffuse indirect light. They're
ideal if you have a dynamic object such as a character that can move
about
static non-moving geometry such as a level in a game, and you want that
dynamic object to be affected by the light bouncing off that static
geometry.

To use irradiance volumes, you need to precompute, or *bake*, the
indirect
light in your scene. Bevy doesn't currently come with a way to do this.
Fortunately, [Blender] provides a [baking tool] as part of the Eevee
renderer, and its irradiance volumes are compatible with those used by
Bevy.
The [`bevy-baked-gi`] project provides a tool, `export-blender-gi`, that
can
extract the baked irradiance volumes from the Blender `.blend` file and
package them up into a `.ktx2` texture for use by the engine. See the
documentation in the `bevy-baked-gi` project for more details as to this
workflow.

Like all light probes in Bevy, irradiance volumes are 1×1×1 cubes that
can
be arbitrarily scaled, rotated, and positioned in a scene with the
[`bevy_transform::components::Transform`] component. The 3D voxel grid
will
be stretched to fill the interior of the cube, and the illumination from
the
irradiance volume will apply to all fragments within that bounding
region.

Bevy's irradiance volumes are based on Valve's [*ambient cubes*] as used
in
*Half-Life 2* ([Mitchell 2006], slide 27). These encode a single color
of
light from the six 3D cardinal directions and blend the sides together
according to the surface normal.

The primary reason for choosing ambient cubes is to match Blender, so
that
its Eevee renderer can be used for baking. However, they also have some
advantages over the common second-order spherical harmonics approach:
ambient cubes don't suffer from ringing artifacts, they are smaller (6
colors for ambient cubes as opposed to 9 for spherical harmonics), and
evaluation is faster. A smaller basis allows for a denser grid of voxels
with the same storage requirements.

If you wish to use a tool other than `export-blender-gi` to produce the
irradiance volumes, you'll need to pack the irradiance volumes in the
following format. The irradiance volume of resolution *(Rx, Ry, Rz)* is
expected to be a 3D texture of dimensions *(Rx, 2Ry, 3Rz)*. The
unnormalized
texture coordinate *(s, t, p)* of the voxel at coordinate *(x, y, z)*
with
side *S* ∈ *{-X, +X, -Y, +Y, -Z, +Z}* is as follows:

```text
s = x

t = y + ⎰  0 if S ∈ {-X, -Y, -Z}
        ⎱ Ry if S ∈ {+X, +Y, +Z}

        ⎧   0 if S ∈ {-X, +X}
p = z + ⎨  Rz if S ∈ {-Y, +Y}
        ⎩ 2Rz if S ∈ {-Z, +Z}
```

Visually, in a left-handed coordinate system with Y up, viewed from the
right, the 3D texture looks like a stacked series of voxel grids, one
for
each cube side, in this order:

| **+X** | **+Y** | **+Z** |
| ------ | ------ | ------ |
| **-X** | **-Y** | **-Z** |

A terminology note: Other engines may refer to irradiance volumes as
*voxel
global illumination*, *VXGI*, or simply as *light probes*. Sometimes
*light
probe* refers to what Bevy calls a reflection probe. In Bevy, *light
probe*
is a generic term that encompasses all cuboid bounding regions that
capture
indirect illumination, whether based on voxels or not.

Note that, if binding arrays aren't supported (e.g. on WebGPU or WebGL
2),
then only the closest irradiance volume to the view will be taken into
account during rendering.

[*ambient cubes*]:
https://advances.realtimerendering.com/s2006/Mitchell-ShadingInValvesSourceEngine.pdf

[Mitchell 2006]:
https://advances.realtimerendering.com/s2006/Mitchell-ShadingInValvesSourceEngine.pdf

[Blender]: http://blender.org/

[baking tool]:
https://docs.blender.org/manual/en/latest/render/eevee/render_settings/indirect_lighting.html

[`bevy-baked-gi`]: https://github.com/pcwalton/bevy-baked-gi

### Implementation notes

This patch generalizes light probes so as to reuse as much code as
possible between irradiance volumes and the existing reflection probes.
This approach was chosen because both techniques share numerous
similarities:

1. Both irradiance volumes and reflection probes are cuboid bounding
regions.
2. Both are responsible for providing baked indirect light.
3. Both techniques involve presenting a variable number of textures to
the shader from which indirect light is sampled. (In the current
implementation, this uses binding arrays.)
4. Both irradiance volumes and reflection probes require gathering and
sorting probes by distance on CPU.
5. Both techniques require the GPU to search through a list of bounding
regions.
6. Both will eventually want to have falloff so that we can smoothly
blend as objects enter and exit the probes' influence ranges. (This is
not implemented yet to keep this patch relatively small and reviewable.)

To do this, we generalize most of the methods in the reflection probes
patch #11366 to be generic over a trait, `LightProbeComponent`. This
trait is implemented by both `EnvironmentMapLight` (for reflection
probes) and `IrradianceVolume` (for irradiance volumes). Using a trait
will allow us to add more types of light probes in the future. In
particular, I highly suspect we will want real-time reflection planes
for mirrors in the future, which can be easily slotted into this
framework.

## Changelog

> This section is optional. If this was a trivial fix, or has no
externally-visible impact, you can delete this section.

### Added
* A new `IrradianceVolume` asset type is available for baked voxelized
light probes. You can bake the global illumination using Blender or
another tool of your choice and use it in Bevy to apply indirect
illumination to dynamic objects.
2024-02-06 23:23:20 +00:00
NiseVoid
ab9447ac32
Add example for bounding volumes and intersection tests (#11666)
# Objective

- Create an example for bounding volumes and intersection tests

## Solution

- Add an example with a few bounding volumes, created from primitives
- Allow the user to cycle trough the different intersection tests
2024-02-03 17:11:01 +00:00
David M. Lary
5c52d0aeee
System Stepping implemented as Resource (#8453)
# Objective

Add interactive system debugging capabilities to bevy, providing
step/break/continue style capabilities to running system schedules.

* Original implementation: #8063
    - `ignore_stepping()` everywhere was too much complexity
* Schedule-config & Resource discussion: #8168
    - Decided on selective adding of Schedules & Resource-based control

## Solution
Created `Stepping` Resource. This resource can be used to enable
stepping on a per-schedule basis. Systems within schedules can be
individually configured to:
* AlwaysRun: Ignore any stepping state and run every frame
* NeverRun: Never run while stepping is enabled
    - this allows for disabling of systems while debugging
* Break: If we're running the full frame, stop before this system is run

Stepping provides two modes of execution that reflect traditional
debuggers:
* Step-based: Only execute one system at a time
* Continue/Break: Run all systems, but stop before running a system
marked as Break

### Demo

https://user-images.githubusercontent.com/857742/233630981-99f3bbda-9ca6-4cc4-a00f-171c4946dc47.mov

Breakout has been modified to use Stepping. The game runs normally for a
couple of seconds, then stepping is enabled and the game appears to
pause. A list of Schedules & Systems appears with a cursor at the first
System in the list. The demo then steps forward full frames using the
spacebar until the ball is about to hit a brick. Then we step system by
system as the ball impacts a brick, showing the cursor moving through
the individual systems. Finally the demo switches back to frame stepping
as the ball changes course.


### Limitations
Due to architectural constraints in bevy, there are some cases systems
stepping will not function as a user would expect.

#### Event-driven systems
Stepping does not support systems that are driven by `Event`s as events
are flushed after 1-2 frames. Although game systems are not running
while stepping, ignored systems are still running every frame, so events
will be flushed.

This presents to the user as stepping the event-driven system never
executes the system. It does execute, but the events have already been
flushed.

This can be resolved by changing event handling to use a buffer for
events, and only dropping an event once all readers have read it.

The work-around to allow these systems to properly execute during
stepping is to have them ignore stepping:
`app.add_systems(event_driven_system.ignore_stepping())`. This was done
in the breakout example to ensure sound played even while stepping.

#### Conditional Systems
When a system is stepped, it is given an opportunity to run. If the
conditions of the system say it should not run, it will not.

Similar to Event-driven systems, if a system is conditional, and that
condition is only true for a very small time window, then stepping the
system may not execute the system. This includes depending on any sort
of external clock.

This exhibits to the user as the system not always running when it is
stepped.

A solution to this limitation is to ensure any conditions are consistent
while stepping is enabled. For example, all systems that modify any
state the condition uses should also enable stepping.

#### State-transition Systems
Stepping is configured on the per-`Schedule` level, requiring the user
to have a `ScheduleLabel`.

To support state-transition systems, bevy generates needed schedules
dynamically. Currently it’s very difficult (if not impossible, I haven’t
verified) for the user to get the labels for these schedules.

Without ready access to the dynamically generated schedules, and a
resolution for the `Event` lifetime, **stepping of the state-transition
systems is not supported**

---

## Changelog
- `Schedule::run()` updated to consult `Stepping` Resource to determine
which Systems to run each frame
- Added `Schedule.label` as a `BoxedSystemLabel`, along with supporting
`Schedule::set_label()` and `Schedule::label()` methods
- `Stepping` needed to know which `Schedule` was running, and prior to
this PR, `Schedule` didn't track its own label
- Would have preferred to add `Schedule::with_label()` and remove
`Schedule::new()`, but this PR touches enough already
- Added calls to `Schedule.set_label()` to `App` and `World` as needed
- Added `Stepping` resource
- Added `Stepping::begin_frame()` system to `MainSchedulePlugin`
    - Run before `Main::run_main()`
    - Notifies any `Stepping` Resource a new render frame is starting
    
## Migration Guide
- Add a call to `Schedule::set_label()` for any custom `Schedule`
    - This is only required if the `Schedule` will be stepped

---------

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2024-02-03 05:18:38 +00:00
Duncan
176223b406
Fix embedded asset path manipulation (#10383)
# Objective

Fixes #10377

## Solution

Use `Path::strip_prefix` instead of `str::split`. Avoid any explicit "/"
characters in path manipulation.

---

## Changelog

- Added: example of embedded asset loading
- Added: support embedded assets in external crates
- Fixed: resolution of embedded assets
- Fixed: unexpected runtime panic during asset path resolution

## Migration Guide

No API changes.

---------

Co-authored-by: Shane Celis <shane.celis@gmail.com>
2024-02-02 14:49:05 +00:00
Joona Aalto
2bf481c03b
Add Meshable trait and implement meshing for 2D primitives (#11431)
# Objective

The first part of #10569, split up from #11007.

The goal is to implement meshing support for Bevy's new geometric
primitives, starting with 2D primitives. 3D meshing will be added in a
follow-up, and we can consider removing the old mesh shapes completely.

## Solution

Add a `Meshable` trait that primitives need to implement to support
meshing, as suggested by the
[RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/12-primitive-shapes.md#meshing).

```rust
/// A trait for shapes that can be turned into a [`Mesh`].
pub trait Meshable {
    /// The output of [`Self::mesh`]. This can either be a [`Mesh`]
    /// or a builder used for creating a [`Mesh`].
    type Output;

    /// Creates a [`Mesh`] for a shape.
    fn mesh(&self) -> Self::Output;
}
```

This PR implements it for the following primitives:

- `Circle`
- `Ellipse`
- `Rectangle`
- `RegularPolygon`
- `Triangle2d`

The `mesh` method typically returns a builder-like struct such as
`CircleMeshBuilder`. This is needed to support shape-specific
configuration for things like mesh resolution or UV configuration:

```rust
meshes.add(Circle { radius: 0.5 }.mesh().resolution(64));
```

Note that if no configuration is needed, you can even skip calling
`mesh` because `From<MyPrimitive>` is implemented for `Mesh`:

```rust
meshes.add(Circle { radius: 0.5 });
```

I also updated the `2d_shapes` example to use primitives, and tweaked
the colors to have better contrast against the dark background.

Before:

![Old 2D
shapes](https://github.com/bevyengine/bevy/assets/57632562/f1d8c2d5-55be-495f-8ed4-5890154b81ca)

After:

![New 2D
shapes](https://github.com/bevyengine/bevy/assets/57632562/f166c013-34b8-4752-800a-5517b284d978)

Here you can see the UVs and different facing directions: (taken from
#11007, so excuse the 3D primitives at the bottom left)

![UVs and facing
directions](https://github.com/bevyengine/bevy/assets/57632562/eaf0be4e-187d-4b6d-8fb8-c996ba295a8a)

---

## Changelog

- Added `bevy_render::mesh::primitives` module
- Added `Meshable` trait and implemented it for:
  - `Circle`
  - `Ellipse`
  - `Rectangle`
  - `RegularPolygon`
  - `Triangle2d`
- Implemented `Default` and `Copy` for several 2D primitives
- Updated `2d_shapes` example to use primitives
- Tweaked colors in `2d_shapes` example to have better contrast against
the (new-ish) dark background

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-01-29 16:47:47 +00:00
Alice Cecile
149a313850
Add an example demonstrating how to send and receive events in the same system (#11574)
# Objective

- Sending and receiving events of the same type in the same system is a
reasonably common need, generally due to event filtering.
- However, actually doing so is non-trivial, as the borrow checker
simultaneous hates mutable and immutable access.

## Solution

- Demonstrate two sensible patterns for doing so.
- Update the `ManualEventReader` docs to be more clear and link to this
example.

---------

Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
Co-authored-by: Joona Aalto <jondolf.dev@gmail.com>
Co-authored-by: ickk <git@ickk.io>
2024-01-29 16:41:27 +00:00
Elabajaba
35ac1b152e
Update to wgpu 0.19 and raw-window-handle 0.6 (#11280)
# Objective

Keep core dependencies up to date.

## Solution

Update the dependencies.

wgpu 0.19 only supports raw-window-handle (rwh) 0.6, so bumping that was
included in this.

The rwh 0.6 version bump is just the simplest way of doing it. There
might be a way we can take advantage of wgpu's new safe surface creation
api, but I'm not familiar enough with bevy's window management to
untangle it and my attempt ended up being a mess of lifetimes and rustc
complaining about missing trait impls (that were implemented). Thanks to
@MiniaczQ for the (much simpler) rwh 0.6 version bump code.

Unblocks https://github.com/bevyengine/bevy/pull/9172 and
https://github.com/bevyengine/bevy/pull/10812

~~This might be blocked on cpal and oboe updating their ndk versions to
0.8, as they both currently target ndk 0.7 which uses rwh 0.5.2~~ Tested
on android, and everything seems to work correctly (audio properly stops
when minimized, and plays when re-focusing the app).

---

## Changelog

- `wgpu` has been updated to 0.19! The long awaited arcanization has
been merged (for more info, see
https://gfx-rs.github.io/2023/11/24/arcanization.html), and Vulkan
should now be working again on Intel GPUs.
- Targeting WebGPU now requires that you add the new `webgpu` feature
(setting the `RUSTFLAGS` environment variable to
`--cfg=web_sys_unstable_apis` is still required). This feature currently
overrides the `webgl2` feature if you have both enabled (the `webgl2`
feature is enabled by default), so it is not recommended to add it as a
default feature to libraries without putting it behind a flag that
allows library users to opt out of it! In the future we plan on
supporting wasm binaries that can target both webgl2 and webgpu now that
wgpu added support for doing so (see
https://github.com/bevyengine/bevy/issues/11505).
- `raw-window-handle` has been updated to version 0.6.

## Migration Guide

- `bevy_render::instance_index::get_instance_index()` has been removed
as the webgl2 workaround is no longer required as it was fixed upstream
in wgpu. The `BASE_INSTANCE_WORKAROUND` shaderdef has also been removed.
- WebGPU now requires the new `webgpu` feature to be enabled. The
`webgpu` feature currently overrides the `webgl2` feature so you no
longer need to disable all default features and re-add them all when
targeting `webgpu`, but binaries built with both the `webgpu` and
`webgl2` features will only target the webgpu backend, and will only
work on browsers that support WebGPU.
- Places where you conditionally compiled things for webgl2 need to be
updated because of this change, eg:
- `#[cfg(any(not(feature = "webgl"), not(target_arch = "wasm32")))]`
becomes `#[cfg(any(not(feature = "webgl") ,not(target_arch = "wasm32"),
feature = "webgpu"))]`
- `#[cfg(all(feature = "webgl", target_arch = "wasm32"))]` becomes
`#[cfg(all(feature = "webgl", target_arch = "wasm32", not(feature =
"webgpu")))]`
- `if cfg!(all(feature = "webgl", target_arch = "wasm32"))` becomes `if
cfg!(all(feature = "webgl", target_arch = "wasm32", not(feature =
"webgpu")))`
- `create_texture_with_data` now also takes a `TextureDataOrder`. You
can probably just set this to `TextureDataOrder::default()`
- `TextureFormat`'s `block_size` has been renamed to `block_copy_size`
- See the `wgpu` changelog for anything I might've missed:
https://github.com/gfx-rs/wgpu/blob/trunk/CHANGELOG.md

---------

Co-authored-by: François <mockersf@gmail.com>
2024-01-26 18:14:21 +00:00
vero
fb367dac72
Add Animated Material example (#11524)
# Objective

- Fixes #11516

## Solution

- Add Animated Material example (colors are hue-cycling smoothly
per-mesh)


![image](https://github.com/bevyengine/bevy/assets/11307157/c75b9e66-0019-41b8-85ec-647559c6ba01)

Note: this example reproduces the perf issue found in #10610 pretty
consistently, with and without the changes from that PR included. Frame
time is sometimes around 4.3ms, other times around 12-14ms. Its pretty
random per run. I think this clears #10610 for merge.
2024-01-26 13:34:46 +00:00
Manuel Fuchs
79b4f26158
Add custom schedule example (#11527)
# Objective

Fixes #11411

## Solution

- Added a simple example how to create and configure custom schedules
that are run by the `Main` schedule.
- Spot checked some of the API docs used, fixed `App::add_schedule` docs
that referred to a function argument that was removed by #9600.

## Open Questions

- While spot checking the docs, I noticed that the `Schedule` label is
stored in a field called `name` instead of `label`. This seems
unintuitive since the term label is used everywhere else. Should we
change that field name? It was introduced in #9600. If so, I do think
this change would be out of scope for this PR that mainly adds the
example.
2024-01-25 17:51:53 +00:00
Patrick Walton
83d6600267
Implement minimal reflection probes (fixed macOS, iOS, and Android). (#11366)
This pull request re-submits #10057, which was backed out for breaking
macOS, iOS, and Android. I've tested this version on macOS and Android
and on the iOS simulator.

# Objective

This pull request implements *reflection probes*, which generalize
environment maps to allow for multiple environment maps in the same
scene, each of which has an axis-aligned bounding box. This is a
standard feature of physically-based renderers and was inspired by [the
corresponding feature in Blender's Eevee renderer].

## Solution

This is a minimal implementation of reflection probes that allows
artists to define cuboid bounding regions associated with environment
maps. For every view, on every frame, a system builds up a list of the
nearest 4 reflection probes that are within the view's frustum and
supplies that list to the shader. The PBR fragment shader searches
through the list, finds the first containing reflection probe, and uses
it for indirect lighting, falling back to the view's environment map if
none is found. Both forward and deferred renderers are fully supported.

A reflection probe is an entity with a pair of components, *LightProbe*
and *EnvironmentMapLight* (as well as the standard *SpatialBundle*, to
position it in the world). The *LightProbe* component (along with the
*Transform*) defines the bounding region, while the
*EnvironmentMapLight* component specifies the associated diffuse and
specular cubemaps.

A frequent question is "why two components instead of just one?" The
advantages of this setup are:

1. It's readily extensible to other types of light probes, in particular
*irradiance volumes* (also known as ambient cubes or voxel global
illumination), which use the same approach of bounding cuboids. With a
single component that applies to both reflection probes and irradiance
volumes, we can share the logic that implements falloff and blending
between multiple light probes between both of those features.

2. It reduces duplication between the existing *EnvironmentMapLight* and
these new reflection probes. Systems can treat environment maps attached
to cameras the same way they treat environment maps applied to
reflection probes if they wish.

Internally, we gather up all environment maps in the scene and place
them in a cubemap array. At present, this means that all environment
maps must have the same size, mipmap count, and texture format. A
warning is emitted if this restriction is violated. We could potentially
relax this in the future as part of the automatic mipmap generation
work, which could easily do texture format conversion as part of its
preprocessing.

An easy way to generate reflection probe cubemaps is to bake them in
Blender and use the `export-blender-gi` tool that's part of the
[`bevy-baked-gi`] project. This tool takes a `.blend` file containing
baked cubemaps as input and exports cubemap images, pre-filtered with an
embedded fork of the [glTF IBL Sampler], alongside a corresponding
`.scn.ron` file that the scene spawner can use to recreate the
reflection probes.

Note that this is intentionally a minimal implementation, to aid
reviewability. Known issues are:

* Reflection probes are basically unsupported on WebGL 2, because WebGL
2 has no cubemap arrays. (Strictly speaking, you can have precisely one
reflection probe in the scene if you have no other cubemaps anywhere,
but this isn't very useful.)

* Reflection probes have no falloff, so reflections will abruptly change
when objects move from one bounding region to another.

* As mentioned before, all cubemaps in the world of a given type
(diffuse or specular) must have the same size, format, and mipmap count.

Future work includes:

* Blending between multiple reflection probes.

* A falloff/fade-out region so that reflected objects disappear
gradually instead of vanishing all at once.

* Irradiance volumes for voxel-based global illumination. This should
reuse much of the reflection probe logic, as they're both GI techniques
based on cuboid bounding regions.

* Support for WebGL 2, by breaking batches when reflection probes are
used.

These issues notwithstanding, I think it's best to land this with
roughly the current set of functionality, because this patch is useful
as is and adding everything above would make the pull request
significantly larger and harder to review.

---

## Changelog

### Added

* A new *LightProbe* component is available that specifies a bounding
region that an *EnvironmentMapLight* applies to. The combination of a
*LightProbe* and an *EnvironmentMapLight* offers *reflection probe*
functionality similar to that available in other engines.

[the corresponding feature in Blender's Eevee renderer]:
https://docs.blender.org/manual/en/latest/render/eevee/light_probes/reflection_cubemaps.html

[`bevy-baked-gi`]: https://github.com/pcwalton/bevy-baked-gi

[glTF IBL Sampler]: https://github.com/KhronosGroup/glTF-IBL-Sampler
2024-01-19 07:33:52 +00:00
James O'Brien
ea42d14344
Dynamic queries and builder API (#9774)
# Objective
Expand the existing `Query` API to support more dynamic use cases i.e.
scripting.

## Prior Art
 - #6390 
 - #8308 
- #10037

## Solution
- Create a `QueryBuilder` with runtime methods to define the set of
component accesses for a built query.
- Create new `WorldQueryData` implementations `FilteredEntityMut` and
`FilteredEntityRef` as variants of `EntityMut` and `EntityRef` that
provide run time checked access to the components included in a given
query.
- Add new methods to `Query` to create "query lens" with a subset of the
access of the initial query.

### Query Builder
The `QueryBuilder` API allows you to define a query at runtime. At it's
most basic use it will simply create a query with the corresponding type
signature:
```rust
let query = QueryBuilder::<Entity, With<A>>::new(&mut world).build();
// is equivalent to
let query = QueryState::<Entity, With<A>>::new(&mut world);
```
Before calling `.build()` you also have the opportunity to add
additional accesses and filters. Here is a simple example where we add
additional filter terms:
```rust
let entity_a = world.spawn((A(0), B(0))).id();
let entity_b = world.spawn((A(0), C(0))).id();

let mut query_a = QueryBuilder::<Entity>::new(&mut world)
    .with::<A>()
    .without::<C>()
    .build();
            
assert_eq!(entity_a, query_a.single(&world));
```
This alone is useful in that allows you to decide which archetypes your
query will match at runtime. However it is also very limited, consider a
case like the following:
```rust
let query_a = QueryBuilder::<&A>::new(&mut world)
// Add an additional access
    .data::<&B>()
    .build();
```
This will grant the query an additional read access to component B
however we have no way of accessing the data while iterating as the type
signature still only includes &A. For an even more concrete example of
this consider dynamic components:
```rust
let query_a = QueryBuilder::<Entity>::new(&mut world)
// Adding a filter is easy since it doesn't need be read later
    .with_id(component_id_a)
// How do I access the data of this component?
    .ref_id(component_id_b)
    .build();
```
With this in mind the `QueryBuilder` API seems somewhat incomplete by
itself, we need some way method of accessing the components dynamically.
So here's one:
### Query Transmutation
If the problem is not having the component in the type signature why not
just add it? This PR also adds transmute methods to `QueryBuilder` and
`QueryState`. Here's a simple example:
```rust
world.spawn(A(0));
world.spawn((A(1), B(0)));
let mut query = QueryBuilder::<()>::new(&mut world)
    .with::<B>()
    .transmute::<&A>()
    .build();

query.iter(&world).for_each(|a| assert_eq!(a.0, 1));
```
The `QueryState` and `QueryBuilder` transmute methods look quite similar
but are different in one respect. Transmuting a builder will always
succeed as it will just add the additional accesses needed for the new
terms if they weren't already included. Transmuting a `QueryState` will
panic in the case that the new type signature would give it access it
didn't already have, for example:
```rust
let query = QueryState::<&A, Option<&B>>::new(&mut world);
/// This is fine, the access for Option<&A> is less restrictive than &A
query.transmute::<Option<&A>>(&world);
/// Oh no, this would allow access to &B on entities that might not have it, so it panics
query.transmute::<&B>(&world);
/// This is right out
query.transmute::<&C>(&world);
```
This is quite an appealing API to also have available on `Query` however
it does pose one additional wrinkle: In order to to change the iterator
we need to create a new `QueryState` to back it. `Query` doesn't own
it's own state though, it just borrows it, so we need a place to borrow
it from. This is why `QueryLens` exists, it is a place to store the new
state so it can be borrowed when you call `.query()` leaving you with an
API like this:
```rust
fn function_that_takes_a_query(query: &Query<&A>) {
    // ...
}

fn system(query: Query<(&A, &B)>) {
    let lens = query.transmute_lens::<&A>();
    let q = lens.query();
    function_that_takes_a_query(&q);
}
```
Now you may be thinking: Hey, wait a second, you introduced the problem
with dynamic components and then described a solution that only works
for static components! Ok, you got me, I guess we need a bit more:
### Filtered Entity References
Currently the only way you can access dynamic components on entities
through a query is with either `EntityMut` or `EntityRef`, however these
can access all components and so conflict with all other accesses. This
PR introduces `FilteredEntityMut` and `FilteredEntityRef` as
alternatives that have additional runtime checking to prevent accessing
components that you shouldn't. This way you can build a query with a
`QueryBuilder` and actually access the components you asked for:
```rust
let mut query = QueryBuilder::<FilteredEntityRef>::new(&mut world)
    .ref_id(component_id_a)
    .with(component_id_b)
    .build();

let entity_ref = query.single(&world);

// Returns Some(Ptr) as we have that component and are allowed to read it
let a = entity_ref.get_by_id(component_id_a);
// Will return None even though the entity does have the component, as we are not allowed to read it
let b = entity_ref.get_by_id(component_id_b);
```
For the most part these new structs have the exact same methods as their
non-filtered equivalents.

Putting all of this together we can do some truly dynamic ECS queries,
check out the `dynamic` example to see it in action:
```
Commands:
    comp, c   Create new components
    spawn, s  Spawn entities
    query, q  Query for entities
Enter a command with no parameters for usage.

> c A, B, C, Data 4  
Component A created with id: 0
Component B created with id: 1
Component C created with id: 2
Component Data created with id: 3

> s A, B, Data 1
Entity spawned with id: 0v0

> s A, C, Data 0
Entity spawned with id: 1v0

> q &Data
0v0: Data: [1, 0, 0, 0]
1v0: Data: [0, 0, 0, 0]

> q B, &mut Data                                                                                     
0v0: Data: [2, 1, 1, 1]

> q B || C, &Data 
0v0: Data: [2, 1, 1, 1]
1v0: Data: [0, 0, 0, 0]
```
## Changelog
 - Add new `transmute_lens` methods to `Query`.
- Add new types `QueryBuilder`, `FilteredEntityMut`, `FilteredEntityRef`
and `QueryLens`
- `update_archetype_component_access` has been removed, archetype
component accesses are now determined by the accesses set in
`update_component_access`
- Added method `set_access` to `WorldQuery`, this is called before
`update_component_access` for queries that have a restricted set of
accesses, such as those built by `QueryBuilder` or `QueryLens`. This is
primarily used by the `FilteredEntity*` variants and has an empty trait
implementation.
- Added method `get_state` to `WorldQuery` as a fallible version of
`init_state` when you don't have `&mut World` access.

## Future Work
Improve performance of `FilteredEntityMut` and `FilteredEntityRef`,
currently they have to determine the accesses a query has in a given
archetype during iteration which is far from ideal, especially since we
already did the work when matching the archetype in the first place. To
avoid making more internal API changes I have left it out of this PR.

---------

Co-authored-by: Mike Hsu <mike.hsu@gmail.com>
2024-01-16 19:16:49 +00:00
Roman Salnikov
eb9db21113
Camera-driven UI (#10559)
# Objective

Add support for presenting each UI tree on a specific window and
viewport, while making as few breaking changes as possible.

This PR is meant to resolve the following issues at once, since they're
all related.

- Fixes #5622 
- Fixes #5570 
- Fixes #5621 

Adopted #5892 , but started over since the current codebase diverged
significantly from the original PR branch. Also, I made a decision to
propagate component to children instead of recursively iterating over
nodes in search for the root.


## Solution

Add a new optional component that can be inserted to UI root nodes and
propagate to children to specify which camera it should render onto.
This is then used to get the render target and the viewport for that UI
tree. Since this component is optional, the default behavior should be
to render onto the single camera (if only one exist) and warn of
ambiguity if multiple cameras exist. This reduces the complexity for
users with just one camera, while giving control in contexts where it
matters.

## Changelog

- Adds `TargetCamera(Entity)` component to specify which camera should a
node tree be rendered into. If only one camera exists, this component is
optional.
- Adds an example of rendering UI to a texture and using it as a
material in a 3D world.
- Fixes recalculation of physical viewport size when target scale factor
changes. This can happen when the window is moved between displays with
different DPI.
- Changes examples to demonstrate assigning UI to different viewports
and windows and make interactions in an offset viewport testable.
- Removes `UiCameraConfig`. UI visibility now can be controlled via
combination of explicit `TargetCamera` and `Visibility` on the root
nodes.

---------

Co-authored-by: davier <bricedavier@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
2024-01-16 00:39:10 +00:00
Félix Lescaudey de Maneville
01139b3472
Sprite slicing and tiling (#10588)
> Replaces #5213

# Objective

Implement sprite tiling and [9 slice
scaling](https://en.wikipedia.org/wiki/9-slice_scaling) for
`bevy_sprite`.
Allowing slice scaling and texture tiling.

Basic scaling vs 9 slice scaling:


![Traditional_scaling_vs_9-slice_scaling](https://user-images.githubusercontent.com/26703856/177335801-27f6fa27-c569-4ce6-b0e6-4f54e8f4e80a.svg)

Slicing example:

<img width="481" alt="Screenshot 2022-07-05 at 15 05 49"
src="https://user-images.githubusercontent.com/26703856/177336112-9e961af0-c0af-4197-aec9-430c1170a79d.png">

Tiling example:

<img width="1329" alt="Screenshot 2023-11-16 at 13 53 32"
src="https://github.com/bevyengine/bevy/assets/26703856/14db39b7-d9e0-4bc3-ba0e-b1f2db39ae8f">

# Solution

- `SpriteBundlue` now has a `scale_mode` component storing a
`SpriteScaleMode` enum with three variants:
  - `Stretched` (default) 
  - `Tiled` to have sprites tile horizontally and/or vertically
- `Sliced` allowing 9 slicing the texture and optionally tile some
sections with a `Textureslicer`.
- `bevy_sprite` has two extra systems to compute a
`ComputedTextureSlices` if necessary,:
- One system react to changes on `Sprite`, `Handle<Image>` or
`SpriteScaleMode`
- The other listens to `AssetEvent<Image>` to compute slices on sprites
when the texture is ready or changed
- I updated the `bevy_sprite` extraction stage to extract potentially
multiple textures instead of one, depending on the presence of
`ComputedTextureSlices`
- I added two examples showcasing the slicing and tiling feature.

The addition of `ComputedTextureSlices` as a cache is to avoid querying
the image data, to retrieve its dimensions, every frame in a extract or
prepare stage. Also it reacts to changes so we can have stuff like this
(tiling example):


https://github.com/bevyengine/bevy/assets/26703856/a349a9f3-33c3-471f-8ef4-a0e5dfce3b01

# Related 

- [ ] Once #5103 or #10099 is merged I can enable tiling and slicing for
texture sheets as ui

# To discuss

There is an other option, to consider slice/tiling as part of the asset,
using the new asset preprocessing but I have no clue on how to do it.

Also, instead of retrieving the Image dimensions, we could use the same
system as the sprite sheet and have the user give the image dimensions
directly (grid). But I think it's less user friendly

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
2024-01-15 15:40:06 +00:00
Charles Bournhonesque
8c6d9b8103
Add support for updating the tracing subscriber in LogPlugin (#10822)
# Objective

This PR is heavily inspired by
https://github.com/bevyengine/bevy/pull/7682
It aims to solve the same problem: allowing the user to extend the
tracing subscriber with extra layers.

(in my case, I'd like to use `use
metrics_tracing_context::{MetricsLayer, TracingContextLayer};`)


## Solution

I'm proposing a different api where the user has the opportunity to take
the existing `subscriber` and apply any transformations on it.

---

## Changelog

- Added a `update_subscriber` option on the `LogPlugin` that lets the
user modify the `subscriber` (for example to extend it with more tracing
`Layers`


## Migration Guide

> This section is optional. If there are no breaking changes, you can
delete this section.

- Added a new field `update_subscriber` in the `LogPlugin`

---------

Co-authored-by: Charles Bournhonesque <cbournhonesque@snapchat.com>
2024-01-15 15:26:13 +00:00
François
3d996639a0
Revert "Implement minimal reflection probes. (#10057)" (#11307)
# Objective

- Fix working on macOS, iOS, Android on main 
- Fixes #11281 
- Fixes #11282 
- Fixes #11283 
- Fixes #11299

## Solution

- Revert #10057
2024-01-12 20:41:51 +00:00
Stepan Koltsov
06bf928927
Option to enable deterministic rendering (#11248)
# Objective

Issue #10243: rendering multiple triangles in the same place results in
flickering.

## Solution

Considered these alternatives:
- `depth_bias` may not work, because of high number of entities, so
creating a material per entity is practically not possible
- rendering at slightly different positions does not work, because when
camera is far, float rounding causes the same issues (edit: assuming we
have to use the same `depth_bias`)
- considered implementing deterministic operation like
`query.par_iter().flat_map(...).collect()` to be used in
`check_visibility` system (which would solve the issue since query is
deterministic), and could not figure out how to make it as cheap as
current approach with thread-local collectors (#11249)

So adding an option to sort entities after `check_visibility` system
run.

Should not be too bad, because after visibility check, only a handful
entities remain.

This is probably not the only source of non-determinism in Bevy, but
this is one I could find so far. At least it fixes the repro example.

## Changelog

- `DeterministicRenderingConfig` option to enable deterministic
rendering

## Test

<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/28969/c735bce1-3a71-44cd-8677-c19f6c0ee6bd">

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-01-09 00:46:01 +00:00
Stepan Koltsov
42e990861c
Remove apply_deferred example (#11142)
# Objective

Re this comment:
https://github.com/bevyengine/bevy/pull/11141#issuecomment-1872455313

Since https://github.com/bevyengine/bevy/pull/9822, Bevy automatically
inserts `apply_deferred` between systems with dependencies where needed,
so manually inserted `apply_deferred` doesn't to anything useful, and in
current state this example does more harm than good.

## Solution

The example can be modified with removal of automatic `apply_deferred`
insertion, but that would immediately upgrade this example from beginner
level, to upper intermediate. Most users don't need to disable automatic
sync point insertion, and remaining few who do probably already know how
it works.

CC @hymm
2024-01-08 22:34:32 +00:00
Patrick Walton
54a943d232
Implement minimal reflection probes. (#10057)
# Objective

This pull request implements *reflection probes*, which generalize
environment maps to allow for multiple environment maps in the same
scene, each of which has an axis-aligned bounding box. This is a
standard feature of physically-based renderers and was inspired by [the
corresponding feature in Blender's Eevee renderer].

## Solution

This is a minimal implementation of reflection probes that allows
artists to define cuboid bounding regions associated with environment
maps. For every view, on every frame, a system builds up a list of the
nearest 4 reflection probes that are within the view's frustum and
supplies that list to the shader. The PBR fragment shader searches
through the list, finds the first containing reflection probe, and uses
it for indirect lighting, falling back to the view's environment map if
none is found. Both forward and deferred renderers are fully supported.

A reflection probe is an entity with a pair of components, *LightProbe*
and *EnvironmentMapLight* (as well as the standard *SpatialBundle*, to
position it in the world). The *LightProbe* component (along with the
*Transform*) defines the bounding region, while the
*EnvironmentMapLight* component specifies the associated diffuse and
specular cubemaps.

A frequent question is "why two components instead of just one?" The
advantages of this setup are:

1. It's readily extensible to other types of light probes, in particular
*irradiance volumes* (also known as ambient cubes or voxel global
illumination), which use the same approach of bounding cuboids. With a
single component that applies to both reflection probes and irradiance
volumes, we can share the logic that implements falloff and blending
between multiple light probes between both of those features.

2. It reduces duplication between the existing *EnvironmentMapLight* and
these new reflection probes. Systems can treat environment maps attached
to cameras the same way they treat environment maps applied to
reflection probes if they wish.

Internally, we gather up all environment maps in the scene and place
them in a cubemap array. At present, this means that all environment
maps must have the same size, mipmap count, and texture format. A
warning is emitted if this restriction is violated. We could potentially
relax this in the future as part of the automatic mipmap generation
work, which could easily do texture format conversion as part of its
preprocessing.

An easy way to generate reflection probe cubemaps is to bake them in
Blender and use the `export-blender-gi` tool that's part of the
[`bevy-baked-gi`] project. This tool takes a `.blend` file containing
baked cubemaps as input and exports cubemap images, pre-filtered with an
embedded fork of the [glTF IBL Sampler], alongside a corresponding
`.scn.ron` file that the scene spawner can use to recreate the
reflection probes.

Note that this is intentionally a minimal implementation, to aid
reviewability. Known issues are:

* Reflection probes are basically unsupported on WebGL 2, because WebGL
2 has no cubemap arrays. (Strictly speaking, you can have precisely one
reflection probe in the scene if you have no other cubemaps anywhere,
but this isn't very useful.)

* Reflection probes have no falloff, so reflections will abruptly change
when objects move from one bounding region to another.

* As mentioned before, all cubemaps in the world of a given type
(diffuse or specular) must have the same size, format, and mipmap count.

Future work includes:

* Blending between multiple reflection probes.

* A falloff/fade-out region so that reflected objects disappear
gradually instead of vanishing all at once.

* Irradiance volumes for voxel-based global illumination. This should
reuse much of the reflection probe logic, as they're both GI techniques
based on cuboid bounding regions.

* Support for WebGL 2, by breaking batches when reflection probes are
used.

These issues notwithstanding, I think it's best to land this with
roughly the current set of functionality, because this patch is useful
as is and adding everything above would make the pull request
significantly larger and harder to review.

---

## Changelog

### Added

* A new *LightProbe* component is available that specifies a bounding
region that an *EnvironmentMapLight* applies to. The combination of a
*LightProbe* and an *EnvironmentMapLight* offers *reflection probe*
functionality similar to that available in other engines.

[the corresponding feature in Blender's Eevee renderer]:
https://docs.blender.org/manual/en/latest/render/eevee/light_probes/reflection_cubemaps.html

[`bevy-baked-gi`]: https://github.com/pcwalton/bevy-baked-gi

[glTF IBL Sampler]: https://github.com/KhronosGroup/glTF-IBL-Sampler
2024-01-08 22:09:17 +00:00
Patrick Walton
dd14f3a477
Implement lightmaps. (#10231)
![Screenshot](https://i.imgur.com/A4KzWFq.png)

# Objective

Lightmaps, textures that store baked global illumination, have been a
mainstay of real-time graphics for decades. Bevy currently has no
support for them, so this pull request implements them.

## Solution

The new `Lightmap` component can be attached to any entity that contains
a `Handle<Mesh>` and a `StandardMaterial`. When present, it will be
applied in the PBR shader. Because multiple lightmaps are frequently
packed into atlases, each lightmap may have its own UV boundaries within
its texture. An `exposure` field is also provided, to control the
brightness of the lightmap.

Note that this PR doesn't provide any way to bake the lightmaps. That
can be done with [The Lightmapper] or another solution, such as Unity's
Bakery.

---

## Changelog

### Added
* A new component, `Lightmap`, is available, for baked global
illumination. If your mesh has a second UV channel (UV1), and you attach
this component to the entity with that mesh, Bevy will apply the texture
referenced in the lightmap.

[The Lightmapper]: https://github.com/Naxela/The_Lightmapper

---------

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2024-01-02 20:38:47 +00:00
Nurzhan Sakén
8067e46049
Add example for pixel-perfect grid snapping in 2D (#8112)
# Objective

Provide an example of how to achieve pixel-perfect "grid snapping" in 2D
via rendering to a texture. This is a common use case in retro pixel art
game development.

## Solution

Render sprites to a canvas via a Camera, then use another (scaled up)
Camera to render the resulting canvas to the screen. This example is
based on the `3d/render_to_texture.rs` example. Furthermore, this
example demonstrates mixing retro-style graphics with high-resolution
graphics, as well as pixel-snapped rendering of a
`MaterialMesh2dBundle`.
2023-12-26 17:15:50 +00:00
Zachary Harrold
46b8e904f4
Added Method to Allow Pipelined Asset Loading (#10565)
# Objective

- Fixes #10518

## Solution

I've added a method to `LoadContext`, `load_direct_with_reader`, which
mirrors the behaviour of `load_direct` with a single key difference: it
is provided with the `Reader` by the caller, rather than getting it from
the contained `AssetServer`. This allows for an `AssetLoader` to process
its `Reader` stream, and then directly hand the results off to the
`LoadContext` to handle further loading. The outer `AssetLoader` can
control how the `Reader` is interpreted by providing a relevant
`AssetPath`.

For example, a Gzip decompression loader could process the asset
`images/my_image.png.gz` by decompressing the bytes, then handing the
decompressed result to the `LoadContext` with the new path
`images/my_image.png.gz/my_image.png`. This intuitively reflects the
nature of contained assets, whilst avoiding unintended behaviour, since
the generated path cannot be a real file path (a file and folder of the
same name cannot coexist in most file-systems).

```rust
#[derive(Asset, TypePath)]
pub struct GzAsset {
    pub uncompressed: ErasedLoadedAsset,
}

#[derive(Default)]
pub struct GzAssetLoader;

impl AssetLoader for GzAssetLoader {
    type Asset = GzAsset;
    type Settings = ();
    type Error = GzAssetLoaderError;
    fn load<'a>(
        &'a self,
        reader: &'a mut Reader,
        _settings: &'a (),
        load_context: &'a mut LoadContext,
    ) -> BoxedFuture<'a, Result<Self::Asset, Self::Error>> {
        Box::pin(async move {
            let compressed_path = load_context.path();
            let file_name = compressed_path
                .file_name()
                .ok_or(GzAssetLoaderError::IndeterminateFilePath)?
                .to_string_lossy();
            let uncompressed_file_name = file_name
                .strip_suffix(".gz")
                .ok_or(GzAssetLoaderError::IndeterminateFilePath)?;
            let contained_path = compressed_path.join(uncompressed_file_name);

            let mut bytes_compressed = Vec::new();

            reader.read_to_end(&mut bytes_compressed).await?;

            let mut decoder = GzDecoder::new(bytes_compressed.as_slice());

            let mut bytes_uncompressed = Vec::new();

            decoder.read_to_end(&mut bytes_uncompressed)?;

            // Now that we have decompressed the asset, let's pass it back to the
            // context to continue loading

            let mut reader = VecReader::new(bytes_uncompressed);

            let uncompressed = load_context
                .load_direct_with_reader(&mut reader, contained_path)
                .await?;

            Ok(GzAsset { uncompressed })
        })
    }

    fn extensions(&self) -> &[&str] {
        &["gz"]
    }
}
```

Because this example is so prudent, I've included an
`asset_decompression` example which implements this exact behaviour:

```rust
fn main() {
    App::new()
        .add_plugins(DefaultPlugins)
        .init_asset::<GzAsset>()
        .init_asset_loader::<GzAssetLoader>()
        .add_systems(Startup, setup)
        .add_systems(Update, decompress::<Image>)
        .run();
}

fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
    commands.spawn(Camera2dBundle::default());

    commands.spawn((
        Compressed::<Image> {
            compressed: asset_server.load("data/compressed_image.png.gz"),
            ..default()
        },
        Sprite::default(),
        TransformBundle::default(),
        VisibilityBundle::default(),
    ));
}

fn decompress<A: Asset>(
    mut commands: Commands,
    asset_server: Res<AssetServer>,
    mut compressed_assets: ResMut<Assets<GzAsset>>,
    query: Query<(Entity, &Compressed<A>)>,
) {
    for (entity, Compressed { compressed, .. }) in query.iter() {
        let Some(GzAsset { uncompressed }) = compressed_assets.remove(compressed) else {
            continue;
        };

        let uncompressed = uncompressed.take::<A>().unwrap();

        commands
            .entity(entity)
            .remove::<Compressed<A>>()
            .insert(asset_server.add(uncompressed));
    }
}
```

A key limitation to this design is how to type the internally loaded
asset, since the example `GzAssetLoader` is unaware of the internal
asset type `A`. As such, in this example I store the contained asset as
an `ErasedLoadedAsset`, and leave it up to the consumer of the `GzAsset`
to handle typing the final result, which is the purpose of the
`decompress` system. This limitation can be worked around by providing
type information to the `GzAssetLoader`, such as `GzAssetLoader<Image,
ImageAssetLoader>`, but this would require registering the asset loader
for every possible decompression target.

Aside from this limitation, nested asset containerisation works as an
end user would expect; if the user registers a `TarAssetLoader`, and a
`GzAssetLoader`, then they can load assets with compound
containerisation, such as `images.tar.gz`.

---

## Changelog

- Added `LoadContext::load_direct_with_reader`
- Added `asset_decompression` example

## Notes

- While I believe my implementation of a Gzip asset loader is
reasonable, I haven't included it as a public feature of `bevy_asset` to
keep the scope of this PR as focussed as possible.
- I have included `flate2` as a `dev-dependency` for the example; it is
not included in the main dependency graph.
2023-11-16 17:47:31 +00:00
IceSentry
b1aa74d511
Add shader_material_2d example (#10542)
# Objective

- 2d materials have subtle differences with 3d materials that aren't
obvious to beginners

## Solution

- Add an example that shows how to make a 2d material
2023-11-14 02:18:25 +00:00
Markus Ort
fd232ad360
Add UI Materials (#9506)
# Objective

- Add Ui Materials so that UI can render more complex and animated
widgets.
- Fixes #5607 

## Solution
- Create a UiMaterial trait for specifying a Shader Asset and Bind Group
Layout/Data.
- Create a pipeline for rendering these Materials inside the Ui
layout/tree.
- Create a MaterialNodeBundle for simple spawning.

## Changelog

- Created a `UiMaterial` trait for specifying a Shader asset and Bind
Group.
- Created a `UiMaterialPipeline` for rendering said Materials.
- Added Example [`ui_material`
](https://github.com/MarkusTheOrt/bevy/blob/ui_material/examples/ui/ui_material.rs)
for example usage.
- Created
[`UiVertexOutput`](https://github.com/MarkusTheOrt/bevy/blob/ui_material/crates/bevy_ui/src/render/ui_vertex_output.wgsl)
export as VertexData for shaders.
- Created
[`material_ui`](https://github.com/MarkusTheOrt/bevy/blob/ui_material/crates/bevy_ui/src/render/ui_material.wgsl)
shader as default for both Vertex and Fragment shaders.

---------

Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: François <mockersf@gmail.com>
2023-11-03 22:33:01 +00:00
Marco Buono
44928e0df4
StandardMaterial Light Transmission (#8015)
# Objective

<img width="1920" alt="Screenshot 2023-04-26 at 01 07 34"
src="https://user-images.githubusercontent.com/418473/234467578-0f34187b-5863-4ea1-88e9-7a6bb8ce8da3.png">

This PR adds both diffuse and specular light transmission capabilities
to the `StandardMaterial`, with support for screen space refractions.
This enables realistically representing a wide range of real-world
materials, such as:

  - Glass; (Including frosted glass)
  - Transparent and translucent plastics;
  - Various liquids and gels;
  - Gemstones;
  - Marble;
  - Wax;
  - Paper;
  - Leaves;
  - Porcelain.

Unlike existing support for transparency, light transmission does not
rely on fixed function alpha blending, and therefore works with both
`AlphaMode::Opaque` and `AlphaMode::Mask` materials.

## Solution

- Introduces a number of transmission related fields in the
`StandardMaterial`;
- For specular transmission:
- Adds logic to take a view main texture snapshot after the opaque
phase; (in order to perform screen space refractions)
- Introduces a new `Transmissive3d` phase to the renderer, to which all
meshes with `transmission > 0.0` materials are sent.
- Calculates a light exit point (of the approximate mesh volume) using
`ior` and `thickness` properties
- Samples the snapshot texture with an adaptive number of taps across a
`roughness`-controlled radius enabling “blurry” refractions
- For diffuse transmission:
- Approximates transmitted diffuse light by using a second, flipped +
displaced, diffuse-only Lambertian lobe for each light source.

## To Do

- [x] Figure out where `fresnel_mix()` is taking place, if at all, and
where `dielectric_specular` is being calculated, if at all, and update
them to use the `ior` value (Not a blocker, just a nice-to-have for more
correct BSDF)
- To the _best of my knowledge, this is now taking place, after
964340cdd. The fresnel mix is actually "split" into two parts in our
implementation, one `(1 - fresnel(...))` in the transmission, and
`fresnel()` in the light implementations. A surface with more
reflectance now will produce slightly dimmer transmission towards the
grazing angle, as more of the light gets reflected.
- [x] Add `transmission_texture`
- [x] Add `diffuse_transmission_texture`
- [x] Add `thickness_texture`
- [x] Add `attenuation_distance` and `attenuation_color`
- [x] Connect values to glTF loader
  - [x] `transmission` and `transmission_texture`
  - [x] `thickness` and `thickness_texture`
  - [x] `ior`
- [ ] `diffuse_transmission` and `diffuse_transmission_texture` (needs
upstream support in `gltf` crate, not a blocker)
- [x] Add support for multiple screen space refraction “steps”
- [x] Conditionally create no transmission snapshot texture at all if
`steps == 0`
- [x] Conditionally enable/disable screen space refraction transmission
snapshots
- [x] Read from depth pre-pass to prevent refracting pixels in front of
the light exit point
- [x] Use `interleaved_gradient_noise()` function for sampling blur in a
way that benefits from TAA
- [x] Drill down a TAA `#define`, tweak some aspects of the effect
conditionally based on it
- [x] Remove const array that's crashing under HLSL (unless a new `naga`
release with https://github.com/gfx-rs/naga/pull/2496 comes out before
we merge this)
- [ ] Look into alternatives to the `switch` hack for dynamically
indexing the const array (might not be needed, compilers seem to be
decent at expanding it)
- [ ] Add pipeline keys for gating transmission (do we really want/need
this?)
- [x] Tweak some material field/function names?

## A Note on Texture Packing

_This was originally added as a comment to the
`specular_transmission_texture`, `thickness_texture` and
`diffuse_transmission_texture` documentation, I removed it since it was
more confusing than helpful, and will likely be made redundant/will need
to be updated once we have a better infrastructure for preprocessing
assets_

Due to how channels are mapped, you can more efficiently use a single
shared texture image
for configuring the following:

- R - `specular_transmission_texture`
- G - `thickness_texture`
- B - _unused_
- A - `diffuse_transmission_texture`

The `KHR_materials_diffuse_transmission` glTF extension also defines a
`diffuseTransmissionColorTexture`,
that _we don't currently support_. One might choose to pack the
intensity and color textures together,
using RGB for the color and A for the intensity, in which case this
packing advice doesn't really apply.

---

## Changelog

- Added a new `Transmissive3d` render phase for rendering specular
transmissive materials with screen space refractions
- Added rendering support for transmitted environment map light on the
`StandardMaterial` as a fallback for screen space refractions
- Added `diffuse_transmission`, `specular_transmission`, `thickness`,
`ior`, `attenuation_distance` and `attenuation_color` to the
`StandardMaterial`
- Added `diffuse_transmission_texture`, `specular_transmission_texture`,
`thickness_texture` to the `StandardMaterial`, gated behind a new
`pbr_transmission_textures` cargo feature (off by default, for maximum
hardware compatibility)
- Added `Camera3d::screen_space_specular_transmission_steps` for
controlling the number of “layers of transparency” rendered for
transmissive objects
- Added a `TransmittedShadowReceiver` component for enabling shadows in
(diffusely) transmitted light. (disabled by default, as it requires
carefully setting up the `thickness` to avoid self-shadow artifacts)
- Added support for the `KHR_materials_transmission`,
`KHR_materials_ior` and `KHR_materials_volume` glTF extensions
- Renamed items related to temporal jitter for greater consistency

## Migration Guide

- `SsaoPipelineKey::temporal_noise` has been renamed to
`SsaoPipelineKey::temporal_jitter`
- The `TAA` shader def (controlled by the presence of the
`TemporalAntiAliasSettings` component in the camera) has been replaced
with the `TEMPORAL_JITTER` shader def (controlled by the presence of the
`TemporalJitter` component in the camera)
- `MeshPipelineKey::TAA` has been replaced by
`MeshPipelineKey::TEMPORAL_JITTER`
- The `TEMPORAL_NOISE` shader def has been consolidated with
`TEMPORAL_JITTER`
2023-10-31 20:59:02 +00:00
SecretPocketCat
08248126f0
Example time api (#10204)
# Objective

- Fixes #10133 

## Solution

- Add a new example that focuses on using `Virtual` time

## Changelog

### Added

- new `virtual_time` example

### Changed

- moved `time` & `timers` examples to the new `examples/time` folder
2023-10-28 16:05:03 +00:00
Niklas Eicker
317903f42a
Reduce noise in asset processing example (#10262)
# Objective

- Reduce noise to allow users to see previous asset changes and other
logs like from asset reloading
- The example file is named differently than the example

## Solution

- Only print the asset content if there are asset events
- Rename the example file to `asset_processing`
2023-10-25 19:37:03 +00:00
Martín Maita
0dc7e60d0e
Improve WebGPU unstable flags docs (#10163)
# Objective

- Fixes #9382

## Solution

- Added a few extra notes in regards to WebGPU experimental state and
the need of enabling unstable APIs through certain attribute flags in
`cargo_features.md` and the examples `README.md` files.
2023-10-18 17:30:44 +00:00
robtfm
c99351f7c2
allow extensions to StandardMaterial (#7820)
# Objective

allow extending `Material`s (including the built in `StandardMaterial`)
with custom vertex/fragment shaders and additional data, to easily get
pbr lighting with custom modifications, or otherwise extend a base
material.

# Solution

- added `ExtendedMaterial<B: Material, E: MaterialExtension>` which
contains a base material and a user-defined extension.
- added example `extended_material` showing how to use it
- modified AsBindGroup to have "unprepared" functions that return raw
resources / layout entries so that the extended material can combine
them

note: doesn't currently work with array resources, as i can't figure out
how to make the OwnedBindingResource::get_binding() work, as wgpu
requires a `&'a[&'a TextureView]` and i have a `Vec<TextureView>`.

# Migration Guide

manual implementations of `AsBindGroup` will need to be adjusted, the
changes are pretty straightforward and can be seen in the diff for e.g.
the `texture_binding_array` example.

---------

Co-authored-by: Robert Swain <robert.swain@gmail.com>
2023-10-17 21:28:08 +00:00
Nuutti Kotivuori
3d79dc4cdc
Unify FixedTime and Time while fixing several problems (#8964)
# Objective

Current `FixedTime` and `Time` have several problems. This pull aims to
fix many of them at once.

- If there is a longer pause between app updates, time will jump forward
a lot at once and fixed time will iterate on `FixedUpdate` for a large
number of steps. If the pause is merely seconds, then this will just
mean jerkiness and possible unexpected behaviour in gameplay. If the
pause is hours/days as with OS suspend, the game will appear to freeze
until it has caught up with real time.
- If calculating a fixed step takes longer than specified fixed step
period, the game will enter a death spiral where rendering each frame
takes longer and longer due to more and more fixed step updates being
run per frame and the game appears to freeze.
- There is no way to see current fixed step elapsed time inside fixed
steps. In order to track this, the game designer needs to add a custom
system inside `FixedUpdate` that calculates elapsed or step count in a
resource.
- Access to delta time inside fixed step is `FixedStep::period` rather
than `Time::delta`. This, coupled with the issue that `Time::elapsed`
isn't available at all for fixed steps, makes it that time requiring
systems are either implemented to be run in `FixedUpdate` or `Update`,
but rarely work in both.
- Fixes #8800 
- Fixes #8543 
- Fixes #7439
- Fixes #5692

## Solution

- Create a generic `Time<T>` clock that has no processing logic but
which can be instantiated for multiple usages. This is also exposed for
users to add custom clocks.
- Create three standard clocks, `Time<Real>`, `Time<Virtual>` and
`Time<Fixed>`, all of which contain their individual logic.
- Create one "default" clock, which is just `Time` (or `Time<()>`),
which will be overwritten from `Time<Virtual>` on each update, and
`Time<Fixed>` inside `FixedUpdate` schedule. This way systems that do
not care specifically which time they track can work both in `Update`
and `FixedUpdate` without changes and the behaviour is intuitive.
- Add `max_delta` to virtual time update, which limits how much can be
added to virtual time by a single update. This fixes both the behaviour
after a long freeze, and also the death spiral by limiting how many
fixed timestep iterations there can be per update. Possible future work
could be adding `max_accumulator` to add a sort of "leaky bucket" time
processing to possibly smooth out jumps in time while keeping frame rate
stable.
- Many minor tweaks and clarifications to the time functions and their
documentation.

## Changelog

- `Time::raw_delta()`, `Time::raw_elapsed()` and related methods are
moved to `Time<Real>::delta()` and `Time<Real>::elapsed()` and now match
`Time` API
- `FixedTime` is now `Time<Fixed>` and matches `Time` API. 
- `Time<Fixed>` default timestep is now 64 Hz, or 15625 microseconds.
- `Time` inside `FixedUpdate` now reflects fixed timestep time, making
systems portable between `Update ` and `FixedUpdate`.
- `Time::pause()`, `Time::set_relative_speed()` and related methods must
now be called as `Time<Virtual>::pause()` etc.
- There is a new `max_delta` setting in `Time<Virtual>` that limits how
much the clock can jump by a single update. The default value is 0.25
seconds.
- Removed `on_fixed_timer()` condition as `on_timer()` does the right
thing inside `FixedUpdate` now.

## Migration Guide

- Change all `Res<Time>` instances that access `raw_delta()`,
`raw_elapsed()` and related methods to `Res<Time<Real>>` and `delta()`,
`elapsed()`, etc.
- Change access to `period` from `Res<FixedTime>` to `Res<Time<Fixed>>`
and use `delta()`.
- The default timestep has been changed from 60 Hz to 64 Hz. If you wish
to restore the old behaviour, use
`app.insert_resource(Time::<Fixed>::from_hz(60.0))`.
- Change `app.insert_resource(FixedTime::new(duration))` to
`app.insert_resource(Time::<Fixed>::from_duration(duration))`
- Change `app.insert_resource(FixedTime::new_from_secs(secs))` to
`app.insert_resource(Time::<Fixed>::from_seconds(secs))`
- Change `system.on_fixed_timer(duration)` to
`system.on_timer(duration)`. Timers in systems placed in `FixedUpdate`
schedule automatically use the fixed time clock.
- Change `ResMut<Time>` calls to `pause()`, `is_paused()`,
`set_relative_speed()` and related methods to `ResMut<Time<Virtual>>`
calls. The API is the same, with the exception that `relative_speed()`
will return the actual last ste relative speed, while
`effective_relative_speed()` returns 0.0 if the time is paused and
corresponds to the speed that was set when the update for the current
frame started.

## Todo

- [x] Update pull name and description
- [x] Top level documentation on usage
- [x] Fix examples
- [x] Decide on default `max_delta` value
- [x] Decide naming of the three clocks: is `Real`, `Virtual`, `Fixed`
good?
- [x] Decide if the three clock inner structures should be in prelude
- [x] Decide on best way to configure values at startup: is manually
inserting a new clock instance okay, or should there be config struct
separately?
- [x] Fix links in docs
- [x] Decide what should be public and what not
- [x] Decide how `wrap_period` should be handled when it is changed
- [x] ~~Add toggles to disable setting the clock as default?~~ No,
separate pull if needed.
- [x] Add tests
- [x] Reformat, ensure adheres to conventions etc.
- [x] Build documentation and see that it looks correct

## Contributors

Huge thanks to @alice-i-cecile and @maniwani while building this pull.
It was a shared effort!

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Cameron <51241057+maniwani@users.noreply.github.com>
Co-authored-by: Jerome Humbert <djeedai@gmail.com>
2023-10-16 01:57:55 +00:00
Griffin
a15d152635
Deferred Renderer (#9258)
# Objective

- Add a [Deferred
Renderer](https://en.wikipedia.org/wiki/Deferred_shading) to Bevy.
- This allows subsequent passes to access per pixel material information
before/during shading.
- Accessing this per pixel material information is needed for some
features, like GI. It also makes other features (ex. Decals) simpler to
implement and/or improves their capability. There are multiple
approaches to accomplishing this. The deferred shading approach works
well given the limitations of WebGPU and WebGL2.

Motivation: [I'm working on a GI solution for
Bevy](https://youtu.be/eH1AkL-mwhI)

# Solution
- The deferred renderer is implemented with a prepass and a deferred
lighting pass.
- The prepass renders opaque objects into the Gbuffer attachment
(`Rgba32Uint`). The PBR shader generates a `PbrInput` in mostly the same
way as the forward implementation and then [packs it into the
Gbuffer](ec1465559f/crates/bevy_pbr/src/render/pbr.wgsl (L168)).
- The deferred lighting pass unpacks the `PbrInput` and [feeds it into
the pbr()
function](ec1465559f/crates/bevy_pbr/src/deferred/deferred_lighting.wgsl (L65)),
then outputs the shaded color data.

- There is now a resource
[DefaultOpaqueRendererMethod](ec1465559f/crates/bevy_pbr/src/material.rs (L599))
that can be used to set the default render method for opaque materials.
If materials return `None` from
[opaque_render_method()](ec1465559f/crates/bevy_pbr/src/material.rs (L131))
the `DefaultOpaqueRendererMethod` will be used. Otherwise, custom
materials can also explicitly choose to only support Deferred or Forward
by returning the respective
[OpaqueRendererMethod](ec1465559f/crates/bevy_pbr/src/material.rs (L603))

- Deferred materials can be used seamlessly along with both opaque and
transparent forward rendered materials in the same scene. The [deferred
rendering
example](https://github.com/DGriffin91/bevy/blob/deferred/examples/3d/deferred_rendering.rs)
does this.

- The deferred renderer does not support MSAA. If any deferred materials
are used, MSAA must be disabled. Both TAA and FXAA are supported.

- Deferred rendering supports WebGL2/WebGPU. 

## Custom deferred materials
- Custom materials can support both deferred and forward at the same
time. The
[StandardMaterial](ec1465559f/crates/bevy_pbr/src/render/pbr.wgsl (L166))
does this. So does [this
example](https://github.com/DGriffin91/bevy_glowy_orb_tutorial/blob/deferred/assets/shaders/glowy.wgsl#L56).
- Custom deferred materials that require PBR lighting can create a
`PbrInput`, write it to the deferred GBuffer and let it be rendered by
the `PBRDeferredLightingPlugin`.
- Custom deferred materials that require custom lighting have two
options:
1. Use the base_color channel of the `PbrInput` combined with the
`STANDARD_MATERIAL_FLAGS_UNLIT_BIT` flag.
[Example.](https://github.com/DGriffin91/bevy_glowy_orb_tutorial/blob/deferred/assets/shaders/glowy.wgsl#L56)
(If the unlit bit is set, the base_color is stored as RGB9E5 for extra
precision)
2. A Custom Deferred Lighting pass can be created, either overriding the
default, or running in addition. The a depth buffer is used to limit
rendering to only the required fragments for each deferred lighting
pass. Materials can set their respective depth id via the
[deferred_lighting_pass_id](b79182d2a3/crates/bevy_pbr/src/prepass/prepass_io.wgsl (L95))
attachment. The custom deferred lighting pass plugin can then set [its
corresponding
depth](ec1465559f/crates/bevy_pbr/src/deferred/deferred_lighting.wgsl (L37)).
Then with the lighting pass using
[CompareFunction::Equal](ec1465559f/crates/bevy_pbr/src/deferred/mod.rs (L335)),
only the fragments with a depth that equal the corresponding depth
written in the material will be rendered.

Custom deferred lighting plugins can also be created to render the
StandardMaterial. The default deferred lighting plugin can be bypassed
with `DefaultPlugins.set(PBRDeferredLightingPlugin { bypass: true })`

---------

Co-authored-by: nickrart <nickolas.g.russell@gmail.com>
2023-10-12 22:10:38 +00:00
Rob Parrett
7063c86ed4
Fix some typos (#9934)
# Objective

To celebrate the turning of the seasons, I took a small walk through the
codebase guided by the "[code spell
checker](https://marketplace.visualstudio.com/items?itemName=streetsidesoftware.code-spell-checker)"
VS Code extension and fixed a few typos.
2023-09-26 19:46:24 +00:00
Trashtalk217
e4b368721d
One Shot Systems (#8963)
I'm adopting this ~~child~~ PR.

# Objective

- Working with exclusive world access is not always easy: in many cases,
a standard system or three is more ergonomic to write, and more
modularly maintainable.
- For small, one-off tasks (commonly handled with scripting), running an
event-reader system incurs a small but flat overhead cost and muddies
the schedule.
- Certain forms of logic (e.g. turn-based games) want very fine-grained
linear and/or branching control over logic.
- SystemState is not automatically cached, and so performance can suffer
and change detection breaks.
- Fixes https://github.com/bevyengine/bevy/issues/2192.
- Partial workaround for https://github.com/bevyengine/bevy/issues/279.

## Solution

- Adds a SystemRegistry resource to the World, which stores initialized
systems keyed by their SystemSet.
- Allows users to call world.run_system(my_system) and
commands.run_system(my_system), without re-initializing or losing state
(essential for change detection).
- Add a Callback type to enable convenient use of dynamic one shot
systems and reduce the mental overhead of working with Box<dyn
SystemSet>.
- Allow users to run systems based on their SystemSet, enabling more
complex user-made abstractions.

## Future work

- Parameterized one-shot systems would improve reusability and bring
them closer to events and commands. The API could be something like
run_system_with_input(my_system, my_input) and use the In SystemParam.
- We should evaluate the unification of commands and one-shot systems
since they are two different ways to run logic on demand over a World.

### Prior attempts

- https://github.com/bevyengine/bevy/pull/2234
- https://github.com/bevyengine/bevy/pull/2417
- https://github.com/bevyengine/bevy/pull/4090
- https://github.com/bevyengine/bevy/pull/7999

This PR continues the work done in
https://github.com/bevyengine/bevy/pull/7999.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Federico Rinaldi <gisquerin@gmail.com>
Co-authored-by: MinerSebas <66798382+MinerSebas@users.noreply.github.com>
Co-authored-by: Aevyrie <aevyrie@gmail.com>
Co-authored-by: Alejandro Pascual Pozo <alejandro.pascual.pozo@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Dmytro Banin <banind@cs.washington.edu>
Co-authored-by: James Liu <contact@jamessliu.com>
2023-09-19 20:17:05 +00:00
ira
f3ab38a802
Add example for Camera::viewport_to_world (#7179)
Fixes #7177

---------

Co-authored-by: Rob Parrett <robparrett@gmail.com>
2023-09-11 18:52:11 +00:00