# Objective
In a few examples, we're specifying a font or font size that is the same
as the current default value. Might as well use the default. That'll be
one less thing to worry about if we ever need to change the default font
size. (wink)
In a few others, we were using a value of `25.0` and it didn't seem like
it was different for an important reason, so I switched to the default
there too.
(There are a bunch of examples that use non-default font sizes for
various reasons. Not trying address them all here.)
# Objective
A couple issues with this example are evident from this screenshot of
the example showcase:
<img width="319" alt="image"
src="https://github.com/bevyengine/bevy/assets/200550/5325bb29-9576-4989-a5a3-a972c8bbf1af">
- The images are misaligned, closer to the right edge of the screen
- The example uses a custom window resolution with a different aspect
ratio from the default, which results in black bars
## Solution
- Use the default window size
- Adjust positions so that things are centered
This isn't really fixing a problem, but I also:
- Used the default font size and adjusted the text labels and gaps so
that everything still fits
Which is how I got here in the first place (one less font size to adjust
for the cosmic text PR).
## Before
<img width="1350" alt="Screenshot 2024-06-20 at 12 23 10 PM"
src="https://github.com/bevyengine/bevy/assets/200550/1c7cfcfe-7edc-4561-a4e7-9b3bc8f87f75">
## After
<img width="1280" alt="Screenshot 2024-06-20 at 12 23 30 PM"
src="https://github.com/bevyengine/bevy/assets/200550/abab8a46-4e11-4ee6-a407-ae3b8bf31975">
# Objective
The documentation for
[`Transform::align`](https://docs.rs/bevy/0.14.0-rc.3/bevy/transform/components/struct.Transform.html#method.align)
mentions a hypothetical ship model. Showing this concretely would be a
nice improvement over using a cube.
> 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(Dir3::X, v, Dir3::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.
## Solution
This commit makes the ship less hypothetical by using a kenney ship
model in the example.
The local axes for the ship needed to change to accommodate the gltf, so
the hypothetical in the documentation and this example's local axes
don't necessarily match. Docs use `align(Dir3::X, v, Dir3::Y, w)` and
this example now uses `(Vec3::NEG_Z, *first, Vec3::X, *second)`.
I manually modified the `craft_speederD` Node's `translation` to be
0,0,0 in the gltf file, which means it now differs from kenney's
original model.
Original ship from: https://kenney.nl/assets/space-kit
## Testing
```
cargo run --example align
```
# Objective
Fixes#13920
## Solution
As described in the issue.
## Testing
Moved a custom transition plugin in example before any of the app-state
methods.
# Objective
[`StableInterpolate`](https://dev-docs.bevyengine.org/bevy/math/trait.StableInterpolate.html)
was introduced after this example was written (or more accurately, the
two PRs were merged on the same day and developed in parallel).
The example used `Vec3::lerp` where I believe it is now preferred to use
`smooth_nudge`.
## Solution
Its not entirely clear to me whether `StableInterpolate` should be
preferred in this scenario, although it seems likely. So I figured a PR
to make the change would either result in it being merged or denied with
a reason.
## Testing
```
cargo run --example 2d_top_down_camera
```
Co-authored-by: François Mockers <mockersf@gmail.com>
# Objective
A very common way to organize a first-person view is to split it into
two kinds of models:
- The *view model* is the model that represents the player's body.
- The *world model* is everything else.
The reason for this distinction is that these two models should be
rendered with different FOVs.
The view model is typically designed and animated with a very specific
FOV in mind, so it is
generally *fixed* and cannot be changed by a player. The world model, on
the other hand, should
be able to change its FOV to accommodate the player's preferences for
the following reasons:
- *Accessibility*: How prone is the player to motion sickness? A wider
FOV can help.
- *Tactical preference*: Does the player want to see more of the
battlefield?
Or have a more zoomed-in view for precision aiming?
- *Physical considerations*: How well does the in-game FOV match the
player's real-world FOV?
Are they sitting in front of a monitor or playing on a TV in the living
room? How big is the screen?
## Solution
I've added an example implementing the described setup as follows.
The `Player` is an entity holding two cameras, one for each model. The
view model camera has a fixed
FOV of 70 degrees, while the world model camera has a variable FOV that
can be changed by the player.
I use different `RenderLayers` to select what to render.
- The world model camera has no explicit `RenderLayers` component, so it
uses the layer 0.
All static objects in the scene are also on layer 0 for the same reason.
- The view model camera has a `RenderLayers` component with layer 1, so
it only renders objects
explicitly assigned to layer 1. The arm of the player is one such
object.
The order of the view model camera is additionally bumped to 1 to ensure
it renders on top of the world model.
- The light source in the scene must illuminate both the view model and
the world model, so it is
assigned to both layers 0 and 1.
To better see the effect, the player can move the camera by dragging
their mouse and change the world model's FOV with the arrow keys. The
arrow up key maps to "decrease FOV" and the arrow down key maps to
"increase FOV". This sounds backwards on paper, but is more intuitive
when actually changing the FOV in-game since a decrease in FOV looks
like a zoom-in.
I intentionally do not allow changing the view model's FOV even though
it would be illustrative because that would be an anti-pattern and bloat
the code a bit.
The example is called `first_person_view_model` and not just
`first_person` because I want to highlight that this is not a simple
flycam, but actually renders the player.
## Testing
Default FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/8c2e804f-fac2-48c7-8a22-d85af999dfb2">
Decreased FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/1733b3e5-f583-4214-a454-3554e3cbd066">
Increased FOV:
<img width="1392" alt="image"
src="https://github.com/bevyengine/bevy/assets/9047632/0b0640e6-5743-46f6-a79a-7181ba9678e8">
Note that the white bar on the right represents the player's arm, which
is more obvious in-game because you can move the camera around.
The box on top is there to make sure that the view model is receiving
shadows.
I tested only on macOS.
---
## Changelog
I don't think new examples go in here, do they?
## Caveat
The solution used here was implemented with help by @robtfm on
[Discord](https://discord.com/channels/691052431525675048/866787577687310356/1241019224491561000):
> shadow maps are specific to lights, not to layers
> if you want shadows from some meshes that are not visible, you could
have light on layer 1+2, meshes on layer 2, camera on layer 1 (for
example)
> but this might change in future, it's not exactly an intended feature
In other words, the example code as-is is not guaranteed to work in the
future. I want to bring this up because the use-case presented here is
extremely common in first-person games and important for accessibility.
It would be good to have a blessed and easy way of how to achieve it.
I'm also not happy about how I get the `perspective` variable in
`change_fov`. Very open to suggestions :)
## Related issues
- Addresses parts of #12658
- Addresses parts of #12588
---------
Co-authored-by: Pascal Hertleif <killercup@gmail.com>
# Objective
- Observers example is using an unseeded random, prints text to console
and doesn't display text as other examples
## Solution
- use seeded random
- log instead of printing
- use common settings for UI text
# Objective
- Provide an expressive way to register dynamic behavior in response to
ECS changes that is consistent with existing bevy types and traits as to
provide a smooth user experience.
- Provide a mechanism for immediate changes in response to events during
command application in order to facilitate improved query caching on the
path to relations.
## Solution
- A new fundamental ECS construct, the `Observer`; inspired by flec's
observers but adapted to better fit bevy's access patterns and rust's
type system.
---
## Examples
There are 3 main ways to register observers. The first is a "component
observer" that looks like this:
```rust
world.observe(|trigger: Trigger<OnAdd, Transform>, query: Query<&Transform>| {
let transform = query.get(trigger.entity()).unwrap();
});
```
The above code will spawn a new entity representing the observer that
will run it's callback whenever the `Transform` component is added to an
entity. This is a system-like function that supports dependency
injection for all the standard bevy types: `Query`, `Res`, `Commands`
etc. It also has a `Trigger` parameter that provides information about
the trigger such as the target entity, and the event being triggered.
Importantly these systems run during command application which is key
for their future use to keep ECS internals up to date. There are similar
events for `OnInsert` and `OnRemove`, and this will be expanded with
things such as `ArchetypeCreated`, `TableEmpty` etc. in follow up PRs.
Another way to register an observer is an "entity observer" that looks
like this:
```rust
world.entity_mut(entity).observe(|trigger: Trigger<Resize>| {
// ...
});
```
Entity observers run whenever an event of their type is triggered
targeting that specific entity. This type of observer will de-spawn
itself if the entity (or entities) it is observing is ever de-spawned so
as to not leave dangling observers.
Entity observers can also be spawned from deferred contexts such as
other observers, systems, or hooks using commands:
```rust
commands.entity(entity).observe(|trigger: Trigger<Resize>| {
// ...
});
```
Observers are not limited to in built event types, they can be used with
any type that implements `Event` (which has been extended to implement
Component). This means events can also carry data:
```rust
#[derive(Event)]
struct Resize { x: u32, y: u32 }
commands.entity(entity).observe(|trigger: Trigger<Resize>, query: Query<&mut Size>| {
let event = trigger.event();
// ...
});
// Will trigger the observer when commands are applied.
commands.trigger_targets(Resize { x: 10, y: 10 }, entity);
```
You can also trigger events that target more than one entity at a time:
```rust
commands.trigger_targets(Resize { x: 10, y: 10 }, [e1, e2]);
```
Additionally, Observers don't _need_ entity targets:
```rust
app.observe(|trigger: Trigger<Quit>| {
})
commands.trigger(Quit);
```
In these cases, `trigger.entity()` will be a placeholder.
Observers are actually just normal entities with an `ObserverState` and
`Observer` component! The `observe()` functions above are just shorthand
for:
```rust
world.spawn(Observer::new(|trigger: Trigger<Resize>| {});
```
This will spawn the `Observer` system and use an `on_add` hook to add
the `ObserverState` component.
Dynamic components and trigger types are also fully supported allowing
for runtime defined trigger types.
## Possible Follow-ups
1. Deprecate `RemovedComponents`, observers should fulfill all use cases
while being more flexible and performant.
2. Queries as entities: Swap queries to entities and begin using
observers listening to archetype creation triggers to keep their caches
in sync, this allows unification of `ObserverState` and `QueryState` as
well as unlocking several API improvements for `Query` and the
management of `QueryState`.
3. Trigger bubbling: For some UI use cases in particular users are
likely to want some form of bubbling for entity observers, this is
trivial to implement naively but ideally this includes an acceleration
structure to cache hierarchy traversals.
4. All kinds of other in-built trigger types.
5. Optimization; in order to not bloat the complexity of the PR I have
kept the implementation straightforward, there are several areas where
performance can be improved. The focus for this PR is to get the
behavior implemented and not incur a performance cost for users who
don't use observers.
I am leaving each of these to follow up PR's in order to keep each of
them reviewable as this already includes significant changes.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: MiniaczQ <xnetroidpl@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
While learning about shaders and pipelines, I found this example to be
misleading; it wasn't clear to me how the node knew what the correct
"instance" of `PostProcessSettings` we should send to the shader (as the
combination of `ExtractComponentPlugin` and `UniformComponentPlugin`
extracts + sends _all_ of our `PostProcessSetting` components to the
GPU).
The goal of this PR is to clarify how to target the view specific
`PostProcessSettings` in the shader when there are multiple cameras.
## Solution
To accomplish this, we can use a dynamic uniform buffer for
`PostProcessSettings`, querying for the relevant `DynamicUniformIndex`
in the `PostProcessNode` to get the relevant index to use with the bind
group.
While the example in its current state is _correct_, I believe that fact
that it's intended to showcase a per camera post processing effect
warrants a dynamic uniform buffer (even though in the context of this
example we have only one camera, and therefore no adverse behaviour).
## Testing
- Run the `post_processing` example before and after this change,
verifying they behave the same.
## Reviewer notes
This is my first PR to Bevy, and I'm by no means an expert in the world
of rendering (though I'm trying to learn all I can). If there's a better
way to do this / a reason not to take this route, I'd love to hear it!
Thanks in advance.
# Objective
- Add a new example showcasing how to add custom primitives and what you
can do with them.
## Solution
- Added a new example `custom_primitives` with a 2D heart shape
primitive highlighting
- `Bounded2d` by implementing and visualising bounding shapes,
- `Measured2d` by implementing it,
- `Meshable` to show the shape on the screen
- The example also includes an `Extrusion<Heart>` implementing
- `Measured3d`,
- `Bounded3d` using the `BoundedExtrusion` trait and
- meshing using the `Extrudable` trait.
## Additional information
Here are two images of the heart and its extrusion:
---------
Co-authored-by: Jakub Marcowski <37378746+Chubercik@users.noreply.github.com>
# Objective
- My attempt at fulfilling #13629.
## Solution
Renames the `and_then` / `or_else` run condition methods to `and` /
`or`, respectively.
Extends the run conditions API to include a suite of binary logical
operators:
- `and`
- `or`
- `nand`
- `nor`
- `xor`
- `xnor`
## Testing
- Did you test these changes? If so, how?
- The test **run_condition_combinators** was extended to include the
added run condition combinators. A **double_counter** system was added
to test for combinators running on even count cycles.
- Are there any parts that need more testing?
- I'm not too sure how I feel about the "counter" style of testing but I
wanted to keep it consistent. If it's just a unit test I would prefer
simply to just assert `true` == _combinator output_ or `false` ==
_combinator output_ .
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
- Nothing too specific. The added methods should be equivalent to the
logical operators they are analogous to (`&&` , `||`, `^`, `!`).
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
- Should not be relevant, I'm using Windows.
## Changelog
- What changed as a result of this PR?
- The run conditions API.
- If applicable, organize changes under "Added", "Changed", or "Fixed"
sub-headings
- Changed:
- `and_then` run condition combinator renamed to simply `and`
- `or_else` run condition combinator renamed to simply `or`
- Added:
- `nand` run condition combinator.
- `nor` run condition combinator.
- `xor` run condition combinator.
- `xnor` run condition combinator.
## Migration Guide
- The `and_then` run condition method has been replaced with the `and`
run condition method.
- The `or_else` run condition method has been replaced with the `or` run
condition method.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Andres O. Vela <andresovela@users.noreply.github.com>
# Objective
Fixes#13711
## Solution
Introduce smaller, generic system sets for each schedule variant, which
are ordered against other generic variants:
- `ExitSchedules<S>` - For `OnExit` schedules, runs from leaf states to
root states.
- `TransitionSchedules<S>` - For `OnTransition` schedules, runs in
arbitrary order.
- `EnterSchedules<S>` - For `OnEnter` schedules, runs from root states
to leaf states.
Also unified `ApplyStateTransition<S>` schedule which works in basically
the same way, just for internals.
## Testing
- One test that tests schedule execution order
---------
Co-authored-by: Lee-Orr <lee-orr@users.noreply.github.com>
# Objective
Partially address #13408
Rework of #13613
Unify the very nice forms of interpolation specifically present in
`bevy_math` under a shared trait upon which further behavior can be
based.
The ideas in this PR were prompted by [Lerp smoothing is broken by Freya
Holmer](https://www.youtube.com/watch?v=LSNQuFEDOyQ).
## Solution
There is a new trait `StableInterpolate` in `bevy_math::common_traits`
which enshrines a quite-specific notion of interpolation with a lot of
guarantees:
```rust
/// A type with a natural interpolation that provides strong subdivision guarantees.
///
/// Although the only required method is `interpolate_stable`, many things are expected of it:
///
/// 1. The notion of interpolation should follow naturally from the semantics of the type, so
/// that inferring the interpolation mode from the type alone is sensible.
///
/// 2. The interpolation recovers something equivalent to the starting value at `t = 0.0`
/// and likewise with the ending value at `t = 1.0`.
///
/// 3. Importantly, the interpolation must be *subdivision-stable*: for any interpolation curve
/// between two (unnamed) values and any parameter-value pairs `(t0, p)` and `(t1, q)`, the
/// interpolation curve between `p` and `q` must be the *linear* reparametrization of the original
/// interpolation curve restricted to the interval `[t0, t1]`.
///
/// The last of these conditions is very strong and indicates something like constant speed. It
/// is called "subdivision stability" because it guarantees that breaking up the interpolation
/// into segments and joining them back together has no effect.
///
/// Here is a diagram depicting it:
/// ```text
/// top curve = u.interpolate_stable(v, t)
///
/// t0 => p t1 => q
/// |-------------|---------|-------------|
/// 0 => u / \ 1 => v
/// / \
/// / \
/// / linear \
/// / reparametrization \
/// / t = t0 * (1 - s) + t1 * s \
/// / \
/// |-------------------------------------|
/// 0 => p 1 => q
///
/// bottom curve = p.interpolate_stable(q, s)
/// ```
///
/// Note that some common forms of interpolation do not satisfy this criterion. For example,
/// [`Quat::lerp`] and [`Rot2::nlerp`] are not subdivision-stable.
///
/// Furthermore, this is not to be used as a general trait for abstract interpolation.
/// Consumers rely on the strong guarantees in order for behavior based on this trait to be
/// well-behaved.
///
/// [`Quat::lerp`]: crate::Quat::lerp
/// [`Rot2::nlerp`]: crate::Rot2::nlerp
pub trait StableInterpolate: Clone {
/// Interpolate between this value and the `other` given value using the parameter `t`.
/// Note that the parameter `t` is not necessarily clamped to lie between `0` and `1`.
/// When `t = 0.0`, `self` is recovered, while `other` is recovered at `t = 1.0`,
/// with intermediate values lying between the two.
fn interpolate_stable(&self, other: &Self, t: f32) -> Self;
}
```
This trait has a blanket implementation over `NormedVectorSpace`, where
`lerp` is used, along with implementations for `Rot2`, `Quat`, and the
direction types using variants of `slerp`. Other areas may choose to
implement this trait in order to hook into its functionality, but the
stringent requirements must actually be met.
This trait bears no direct relationship with `bevy_animation`'s
`Animatable` trait, although they may choose to use `interpolate_stable`
in their trait implementations if they wish, as both traits involve
type-inferred interpolations of the same kind. `StableInterpolate` is
not a supertrait of `Animatable` for a couple reasons:
1. Notions of interpolation in animation are generally going to be much
more general than those allowed under these constraints.
2. Laying out these generalized interpolation notions is the domain of
`bevy_animation` rather than of `bevy_math`. (Consider also that
inferring interpolation from types is not universally desirable.)
Similarly, this is not implemented on `bevy_color`'s color types,
although their current mixing behavior does meet the conditions of the
trait.
As an aside, the subdivision-stability condition is of interest
specifically for the [Curve
RFC](https://github.com/bevyengine/rfcs/pull/80), where it also ensures
a kind of stability for subsampling.
Importantly, this trait ensures that the "smooth following" behavior
defined in this PR behaves predictably:
```rust
/// Smoothly nudge this value towards the `target` at a given decay rate. The `decay_rate`
/// parameter controls how fast the distance between `self` and `target` decays relative to
/// the units of `delta`; the intended usage is for `decay_rate` to generally remain fixed,
/// while `delta` is something like `delta_time` from an updating system. This produces a
/// smooth following of the target that is independent of framerate.
///
/// More specifically, when this is called repeatedly, the result is that the distance between
/// `self` and a fixed `target` attenuates exponentially, with the rate of this exponential
/// decay given by `decay_rate`.
///
/// For example, at `decay_rate = 0.0`, this has no effect.
/// At `decay_rate = f32::INFINITY`, `self` immediately snaps to `target`.
/// In general, higher rates mean that `self` moves more quickly towards `target`.
///
/// # Example
/// ```
/// # use bevy_math::{Vec3, StableInterpolate};
/// # let delta_time: f32 = 1.0 / 60.0;
/// let mut object_position: Vec3 = Vec3::ZERO;
/// let target_position: Vec3 = Vec3::new(2.0, 3.0, 5.0);
/// // Decay rate of ln(10) => after 1 second, remaining distance is 1/10th
/// let decay_rate = f32::ln(10.0);
/// // Calling this repeatedly will move `object_position` towards `target_position`:
/// object_position.smooth_nudge(&target_position, decay_rate, delta_time);
/// ```
fn smooth_nudge(&mut self, target: &Self, decay_rate: f32, delta: f32) {
self.interpolate_stable_assign(target, 1.0 - f32::exp(-decay_rate * delta));
}
```
As the documentation indicates, the intention is for this to be called
in game update systems, and `delta` would be something like
`Time::delta_seconds` in Bevy, allowing positions, orientations, and so
on to smoothly follow a target. A new example, `smooth_follow`,
demonstrates a basic implementation of this, with a sphere smoothly
following a sharply moving target:
https://github.com/bevyengine/bevy/assets/2975848/7124b28b-6361-47e3-acf7-d1578ebd0347
## Testing
Tested by running the example with various parameters.
# Objective
This PR addresses the 2D part of #12658. I plan to separate the examples
and make one PR per camera example.
## Solution
Added a new top-down example composed of:
- [x] Player keyboard movements
- [x] UI for keyboard instructions
- [x] Colors and bloom effect to see the movement of the player
- [x] Camera smooth movement towards the player (lerp)
## Testing
```bash
cargo run --features="wayland,bevy/dynamic_linking" --example 2d_top_down_camera
```
https://github.com/bevyengine/bevy/assets/10638479/95db0587-e5e0-4f55-be11-97444b795793
# Objective
- Where possible, it's recommended to use `BufferVec` over
`encase::StorageBuffer` for performance reason. It doesn't really matter
for the example, but it's still important to teach the better solution.
## Solution
- Use BufferVec in the gpu_readback example
# Objective
- Implement `Meshable` for `Extrusion<T>`
## Solution
- `Meshable` requires `Meshable::Output: MeshBuilder` now. This means
that all `some_primitive.mesh()` calls now return a `MeshBuilder`. These
were added for primitives that did not have one prior to this.
- A new trait `Extrudable: MeshBuilder` has been added. This trait
allows you to specify the indices of the perimeter of the mesh created
by this `MeshBuilder` and whether they are to be shaded smooth or flat.
- `Extrusion<P: Primitive2d + Meshable>` is now `Meshable` aswell. The
associated `MeshBuilder` is `ExtrusionMeshBuilder` which is generic over
`P` and uses the `MeshBuilder` of its baseshape internally.
- `ExtrusionMeshBuilder` exposes the configuration functions of its
base-shapes builder.
- Updated the `3d_shapes` example to include `Extrusion`s
## Migration Guide
- Depending on the context, you may need to explicitly call
`.mesh().build()` on primitives where you have previously called
`.mesh()`
- The `Output` type of custom `Meshable` implementations must now derive
`MeshBuilder`.
## Additional information
- The extrusions UVs are done so that
- the front face (`+Z`) is in the area between `(0, 0)` and `(0.5,
0.5)`,
- the back face (`-Z`) is in the area between `(0.5, 0)` and `(1, 0.5)`
- the mantle is in the area between `(0, 0.5)` and `(1, 1)`. Each
`PerimeterSegment` you specified in the `Extrudable` implementation will
be allocated an equal portion of this area.
- The UVs of the base shape are scaled to be in the front/back area so
whatever method of filling the full UV-space the base shape used is how
these areas will be filled.
Here is an example of what that looks like on a capsule:
https://github.com/bevyengine/bevy/assets/62256001/425ad288-fbbc-4634-9d3f-5e846cdce85f
This is the texture used:
The `3d_shapes` example now looks like this:
---------
Co-authored-by: Lynn Büttgenbach <62256001+solis-lumine-vorago@users.noreply.github.com>
Co-authored-by: Matty <weatherleymatthew@gmail.com>
Co-authored-by: Matty <2975848+mweatherley@users.noreply.github.com>
This commit implements a large subset of [*subpixel morphological
antialiasing*], better known as SMAA. SMAA is a 2011 antialiasing
technique that detects jaggies in an aliased image and smooths them out.
Despite its age, it's been a continual staple of games for over a
decade. Four quality presets are available: *low*, *medium*, *high*, and
*ultra*. I set the default to *high*, on account of modern GPUs being
significantly faster than they were in 2011.
Like the already-implemented FXAA, SMAA works on an unaliased image.
Unlike FXAA, it requires three passes: (1) edge detection; (2) blending
weight calculation; (3) neighborhood blending. Each of the first two
passes writes an intermediate texture for use by the next pass. The
first pass also writes to a stencil buffer in order to dramatically
reduce the number of pixels that the second pass has to examine. Also
unlike FXAA, two built-in lookup textures are required; I bundle them
into the library in compressed KTX2 format.
The [reference implementation of SMAA] is in HLSL, with abundant use of
preprocessor macros to achieve GLSL compatibility. Unfortunately, the
reference implementation predates WGSL by over a decade, so I had to
translate the HLSL to WGSL manually. As much as was reasonably possible
without sacrificing readability, I tried to translate line by line,
preserving comments, both to aid reviewing and to allow patches to the
HLSL to more easily apply to the WGSL. Most of SMAA's features are
supported, but in the interests of making this patch somewhat less huge,
I skipped a few of the more exotic ones:
* The temporal variant is currently unsupported. This is and has been
used in shipping games, so supporting temporal SMAA would be useful
follow-up work. It would, however, require some significant work on TAA
to ensure compatibility, so I opted to skip it in this patch.
* Depth- and chroma-based edge detection are unimplemented; only luma
is. Depth is lower-quality, but faster; chroma is higher-quality, but
slower. Luma is the suggested default edge detection algorithm. (Note
that depth-based edge detection wouldn't work on WebGL 2 anyway, because
of the Naga bug whereby depth sampling is miscompiled in GLSL. This is
the same bug that prevents depth of field from working on that
platform.)
* Predicated thresholding is currently unsupported.
* My implementation is incompatible with SSAA and MSAA, unlike the
original; MSAA must be turned off to use SMAA in Bevy. I believe this
feature was rarely used in practice.
The `anti_aliasing` example has been updated to allow experimentation
with and testing of the different SMAA quality presets. Along the way, I
refactored the example's help text rendering code a bit to eliminate
code repetition.
SMAA is fully supported on WebGL 2.
Fixes#9819.
[*subpixel morphological antialiasing*]: https://www.iryoku.com/smaa/
[reference implementation of SMAA]: https://github.com/iryoku/smaa
## Changelog
### Added
* Subpixel morphological antialiasing, or SMAA, is now available. To use
it, add the `SmaaSettings` component to your `Camera`.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
This PR addresses one of the issues from [discord state
discussion](https://discord.com/channels/691052431525675048/1237949214017716356).
Same-state transitions can be desirable, so there should exist a hook
for them.
Fixes https://github.com/bevyengine/bevy/issues/9130.
## Solution
- Allow `StateTransitionEvent<S>` to contain identity transitions.
- Ignore identity transitions at schedule running level (`OnExit`,
`OnTransition`, `OnEnter`).
- Propagate identity transitions through `SubStates` and
`ComputedStates`.
- Add example about registering custom transition schedules.
## Changelog
- `StateTransitionEvent<S>` can be emitted with same `exited` and
`entered` state.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- With the recent winit update, touchpad specific events can also be
triggered on mobile
## Solution
- Rename them to gestures and add support for the new ones
## Testing
- Tested on the mobile example on iOS
https://github.com/bevyengine/bevy/assets/8672791/da4ed23f-ff0a-41b2-9dcd-726e8546bef2
## Migration Guide
- `TouchpadMagnify` has been renamed to `PinchGesture`
- `TouchpadRotate` has been renamed to `RotationGesture `
---------
Co-authored-by: mike <ramirezmike2@gmail.com>
# Objective
Move `StateScoped` and `log_transitions` to `bevy_state`, since they're
useful for end users.
Addresses #12852, although not in the way the issue had in mind.
## Solution
- Added `bevy_hierarchy` to default features of `bevy_state`.
- Move `log_transitions` to `transitions` module.
- Move `StateScoped` to `state_scoped` module, gated behind
`bevy_hierarchy` feature.
- Refreshed implementation.
- Added `enable_state_coped_entities<S: States>()` to add required
machinery to `App` for clearing state-scoped entities.
## Changelog
- Added `log_transitions` for displaying state transitions.
- Added `StateScoped` for binding entity lifetime to state and app
`enable_state_coped_entities` to register cleaning behavior.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: François Mockers <francois.mockers@vleue.com>
We want to use the clustering infrastructure for light probes and decals
as well, not just point lights. This patch builds on top of #13640 and
performs the rename.
To make this series easier to review, this patch makes no code changes.
Only identifiers and comments are modified.
## Migration Guide
* In the PBR shaders, `point_lights` is now known as
`clusterable_objects`, `PointLight` is now known as `ClusterableObject`,
and `cluster_light_index_lists` is now known as
`clusterable_object_index_lists`.
This commit implements support for physically-based anisotropy in Bevy's
`StandardMaterial`, following the specification for the
[`KHR_materials_anisotropy`] glTF extension.
[*Anisotropy*] (not to be confused with [anisotropic filtering]) is a
PBR feature that allows roughness to vary along the tangent and
bitangent directions of a mesh. In effect, this causes the specular
light to stretch out into lines instead of a round lobe. This is useful
for modeling brushed metal, hair, and similar surfaces. Support for
anisotropy is a common feature in major game and graphics engines;
Unity, Unreal, Godot, three.js, and Blender all support it to varying
degrees.
Two new parameters have been added to `StandardMaterial`:
`anisotropy_strength` and `anisotropy_rotation`. Anisotropy strength,
which ranges from 0 to 1, represents how much the roughness differs
between the tangent and the bitangent of the mesh. In effect, it
controls how stretched the specular highlight is. Anisotropy rotation
allows the roughness direction to differ from the tangent of the model.
In addition to these two fixed parameters, an *anisotropy texture* can
be supplied. Such a texture should be a 3-channel RGB texture, where the
red and green values specify a direction vector using the same
conventions as a normal map ([0, 1] color values map to [-1, 1] vector
values), and the the blue value represents the strength. This matches
the format that the [`KHR_materials_anisotropy`] specification requires.
Such textures should be loaded as linear and not sRGB. Note that this
texture does consume one additional texture binding in the standard
material shader.
The glTF loader has been updated to properly parse the
`KHR_materials_anisotropy` extension.
A new example, `anisotropy`, has been added. This example loads and
displays the barn lamp example from the [`glTF-Sample-Assets`]
repository. Note that the textures were rather large, so I shrunk them
down and converted them to a mixture of JPEG and KTX2 format, in the
interests of saving space in the Bevy repository.
[*Anisotropy*]:
https://google.github.io/filament/Filament.md.html#materialsystem/anisotropicmodel
[anisotropic filtering]:
https://en.wikipedia.org/wiki/Anisotropic_filtering
[`KHR_materials_anisotropy`]:
https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Khronos/KHR_materials_anisotropy/README.md
[`glTF-Sample-Assets`]:
https://github.com/KhronosGroup/glTF-Sample-Assets/
## Changelog
### Added
* Physically-based anisotropy is now available for materials, which
enhances the look of surfaces such as brushed metal or hair. glTF scenes
can use the new feature with the `KHR_materials_anisotropy` extension.
## Screenshots
With anisotropy:
Without anisotropy:
# Objective
- Fixes#10909
- Fixes#8492
## Solution
- Name all matrices `x_from_y`, for example `world_from_view`.
## Testing
- I've tested most of the 3D examples. The `lighting` example
particularly should hit a lot of the changes and appears to run fine.
---
## Changelog
- Renamed matrices across the engine to follow a `y_from_x` naming,
making the space conversion more obvious.
## Migration Guide
- `Frustum`'s `from_view_projection`, `from_view_projection_custom_far`
and `from_view_projection_no_far` were renamed to
`from_clip_from_world`, `from_clip_from_world_custom_far` and
`from_clip_from_world_no_far`.
- `ComputedCameraValues::projection_matrix` was renamed to
`clip_from_view`.
- `CameraProjection::get_projection_matrix` was renamed to
`get_clip_from_view` (this affects implementations on `Projection`,
`PerspectiveProjection` and `OrthographicProjection`).
- `ViewRangefinder3d::from_view_matrix` was renamed to
`from_world_from_view`.
- `PreviousViewData`'s members were renamed to `view_from_world` and
`clip_from_world`.
- `ExtractedView`'s `projection`, `transform` and `view_projection` were
renamed to `clip_from_view`, `world_from_view` and `clip_from_world`.
- `ViewUniform`'s `view_proj`, `unjittered_view_proj`,
`inverse_view_proj`, `view`, `inverse_view`, `projection` and
`inverse_projection` were renamed to `clip_from_world`,
`unjittered_clip_from_world`, `world_from_clip`, `world_from_view`,
`view_from_world`, `clip_from_view` and `view_from_clip`.
- `GpuDirectionalCascade::view_projection` was renamed to
`clip_from_world`.
- `MeshTransforms`' `transform` and `previous_transform` were renamed to
`world_from_local` and `previous_world_from_local`.
- `MeshUniform`'s `transform`, `previous_transform`,
`inverse_transpose_model_a` and `inverse_transpose_model_b` were renamed
to `world_from_local`, `previous_world_from_local`,
`local_from_world_transpose_a` and `local_from_world_transpose_b` (the
`Mesh` type in WGSL mirrors this, however `transform` and
`previous_transform` were named `model` and `previous_model`).
- `Mesh2dTransforms::transform` was renamed to `world_from_local`.
- `Mesh2dUniform`'s `transform`, `inverse_transpose_model_a` and
`inverse_transpose_model_b` were renamed to `world_from_local`,
`local_from_world_transpose_a` and `local_from_world_transpose_b` (the
`Mesh2d` type in WGSL mirrors this).
- In WGSL, in `bevy_pbr::mesh_functions`, `get_model_matrix` and
`get_previous_model_matrix` were renamed to `get_world_from_local` and
`get_previous_world_from_local`.
- In WGSL, `bevy_sprite::mesh2d_functions::get_model_matrix` was renamed
to `get_world_from_local`.
# Objective
- Add GizmoBuilders for some primitives as discussed in #13233
## Solution
- `gizmos.primitive_2d(CIRCLE)` and `gizmos.primitive_2d(ELLIPSE)` now
return `Ellipse2dBuilder` aswell.
- `gizmos.primitive_3d(SPHERE)` and `gizmos.sphere()` now return the
same `SphereBuilder`.
- the `.circle_segments` method on the `SphereBuilder` that used to be
returned by `.sphere()` is now called `.segments`
- the sphere primitive gizmo now matches the `gizmos.sphere` gizmo
- `gizmos.primitive_2d(ANNULUS)` now returns a `Annulus2dBuilder`
allowing the configuration of the `segments`
- gizmos cylinders and capsules now have only 1 line per axis, similar
to `gizmos.sphere`
## Migration Guide
- Some `gizmos.primitive_nd` methods now return some or different
builders. You may need to adjust types and match statements
- Replace any calls to `circle_segments()` with `.segments()`
---------
Co-authored-by: Raphael Büttgenbach <62256001+solis-lumine-vorago@users.noreply.github.com>
# Objective
- Plane subdivision was removed without providing an alternative
## Solution
- Add subdivision to the PlaneMeshBuilder
---
## Migration Guide
If you were using `Plane` `subdivisions`, you now need to use
`Plane3d::default().mesh().subdivisions(10)`
fixes https://github.com/bevyengine/bevy/issues/13258
Currently copypasting the example into a new project without also
copying "shaders/game_of_life.wgsl" gives an unhelpful blank screen.
This change makes it panic instead. I think nicer error handling is
outside scope of the example, and this is good enough to point out that
the shader code is missing.
# Objective
- fixes#4823
## Solution
As outlined in the discussion in the linked issue as the best current
solution, this PR adds specific GltfExtras for
- scenes
- meshes
- materials
- As it is , it is not a breaking change, I hesitated to rename the
current "GltfExtras" component to "PrimitiveGltfExtras", but that would
result in a breaking change and might be a bit confusing as to what
"primitive" that refers to.
## Testing
- I included a bare-bones example & asset (exported gltf file from
Blender) with gltf extras at all the relevant levels : scene, mesh,
material
---
## Changelog
- adds "SceneGltfExtras" injected at the scene level if any
- adds "MeshGltfExtras", injected at the mesh level if any
- adds "MaterialGltfExtras", injected at the mesh level if any: ie if a
mesh has a material that has gltf extras, the component will be injected
there.
# Objective
- Upgrade winit to v0.30
- Fixes https://github.com/bevyengine/bevy/issues/13331
## Solution
This is a rewrite/adaptation of the new trait system described and
implemented in `winit` v0.30.
## Migration Guide
The custom UserEvent is now renamed as WakeUp, used to wake up the loop
if anything happens outside the app (a new
[custom_user_event](https://github.com/bevyengine/bevy/pull/13366/files#diff-2de8c0a8d3028d0059a3d80ae31b2bbc1cde2595ce2d317ea378fe3e0cf6ef2d)
shows this behavior.
The internal `UpdateState` has been removed and replaced internally by
the AppLifecycle. When changed, the AppLifecycle is sent as an event.
The `UpdateMode` now accepts only two values: `Continuous` and
`Reactive`, but the latter exposes 3 new properties to enable reactive
to device, user or window events. The previous `UpdateMode::Reactive` is
now equivalent to `UpdateMode::reactive()`, while
`UpdateMode::ReactiveLowPower` to `UpdateMode::reactive_low_power()`.
The `ApplicationLifecycle` has been renamed as `AppLifecycle`, and now
contains the possible values of the application state inside the event
loop:
* `Idle`: the loop has not started yet
* `Running` (previously called `Started`): the loop is running
* `WillSuspend`: the loop is going to be suspended
* `Suspended`: the loop is suspended
* `WillResume`: the loop is going to be resumed
Note: the `Resumed` state has been removed since the resumed app is just
running.
Finally, now that `winit` enables this, it extends the `WinitPlugin` to
support custom events.
## Test platforms
- [x] Windows
- [x] MacOs
- [x] Linux (x11)
- [x] Linux (Wayland)
- [x] Android
- [x] iOS
- [x] WASM/WebGPU
- [x] WASM/WebGL2
## Outstanding issues / regressions
- [ ] iOS: build failed in CI
- blocking, but may just be flakiness
- [x] Cross-platform: when the window is maximised, changes in the scale
factor don't apply, to make them apply one has to make the window
smaller again. (Re-maximising keeps the updated scale factor)
- non-blocking, but good to fix
- [ ] Android: it's pretty easy to quickly open and close the app and
then the music keeps playing when suspended.
- non-blocking but worrying
- [ ] Web: the application will hang when switching tabs
- Not new, duplicate of https://github.com/bevyengine/bevy/issues/13486
- [ ] Cross-platform?: Screenshot failure, `ERROR present_frames:
wgpu_core::present: No work has been submitted for this frame before`
taking the first screenshot, but after pressing space
- non-blocking, but good to fix
---------
Co-authored-by: François <francois.mockers@vleue.com>
# Objective
Fixes#13606.
Also Fixes#13614.
## Solution
Added the missing trait impls, and made `gizmos.arc_2d()` work with a
counter-clockwise angle.
## Testing
- Updated the render_primitives example, and it works.
# Objective
- Followup to #13548
- It added a list of all possible labels to documentation. This seems
hard to keep up and doesn't stop people from making spelling mistake
## Solution
- Add an enum that can create all the labels possible, and encourage its
use rather than manually typed labels
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
# Objective
- The default font size is too small to be useful in examples or for
debug text.
- Fixes#13587
## Solution
- Updated the default font size value in `TextStyle` from 12px to 24px.
- Resorted to Text defaults in examples to use the default font size in
most of them.
## Testing
- WIP
---
## Migration Guide
- The default font size has been increased to 24px from 12px. Make sure
you set the font to the appropriate values in places you were using
`Default` text style.
# Objective
Unifies the naming convention between `StateTransitionEvent<S>` and
transition schedules.
## Migration Guide
- `StateTransitionEvent<S>` and `OnTransition<S>` schedule had their
fields renamed to `exited` and `entered` to match schedules.
# Objective
- In #13542 I broke example `color_grading`: the UI is not updated to
reflect changed camera settings
- Fixes#13590.
## Solution
- Update the UI when changing color grading
## Objective
Use the "standard" text size / placement for the new text in these
examples.
Continuation of an effort started here:
https://github.com/bevyengine/bevy/pull/8478
This is definitely not comprehensive. I did the ones that were easy to
find and relatively straightforward updates. I meant to just do
`3d_shapes` and `2d_shapes`, but one thing lead to another.
## Solution
Use `font_size: 20.0`, the default (built-in) font, `Color::WHITE`
(default), and `Val::Px(12.)` from the edges of the screen.
There are a few little drive-by cleanups of defaults not being used,
etc.
## Testing
Ran the changed examples, verified that they still look reasonable.
# Objective
- In particularly dark scenes, auto-exposure would lead to an unexpected
darkening of the view.
- Fixes#13446.
## Solution
The average luminance should default to something else than 0.0 instead,
when there are no samples. We set it to `settings.min_log_lum`.
## Testing
I was able to reproduce the problem on the `auto_exposure` example by
setting the point light intensity to 2000 and looking into the
right-hand corner. There was a sudden darkening.
Now, the discontinuity is gone.
---------
Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
Co-authored-by: Bram Buurlage <brambuurlage@gmail.com>
# Objective
- Fixes#13521
## Solution
Set `ambient_intensity` to 0.0 in volumetric_fog example.
I chose setting it explicitly over changing the default in order to make
it clear that this needs to be set depending on whether you have an
`EnvironmentMapLight`. See documentation for `ambient_intensity` and
related members.
## Testing
- Run the volumetric_fog example and notice how the light shown in
#13521 is not there anymore, as expected.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
# Objective
- Small improvements on the `color_grading` example
## Solution
- Simplify button creation by creating them in the default state, the
selected one is automatically selected
- Don't update the UI if not needed
- Also invert the border of the selected button
- Simplify text update
# Objective
- Show + Visually Test that 3D primitive sampling works
- Make an example that looks nice.
## Solution
- Added a `sampling_primitives` examples which shows all the 3D
primitives being sampled, with a firefly aesthetic.
## Testing
- `cargo run --example sampling_primitives`
- Haven't tested WASM.
## Changelog
### Added
- Added a new example, `sampling_primitives`, to showcase all the 3D
sampleable primitives.
## Additional notes:
This example borrowed a bunch of code from the other sampling example,
by @mweatherley.
In future updates this example should be updated with new 3D primitives
as they become sampleable.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Joona Aalto <jondolf.dev@gmail.com>
# Objective
Fixes#13427.
## Solution
I changed the traits, and updated all usages.
## Testing
The `render_primitives` example still works perfectly.
---
## Changelog
- Made `gizmos.primitive_2d()` and `gizmos.primitive_3d()` take the
primitives by ref.
## Migration Guide
- Any usages of `gizmos.primitive_2d()` and/or `gizmos.primitive_3d()`
need to be updated to pass the primitive in by reference.
# Objective
We introduced a bunch of neat random sampling stuff in this release; we
should do a good job of showing people how to use it, and writing
examples is part of this.
## Solution
A new Math example, `random_sampling`, shows off the `ShapeSample` API
functionality. For the moment, it renders a cube and allows the user to
sample points from its interior or boundary in sets of either 1 or 100:
<img width="1440" alt="Screenshot 2024-05-25 at 1 16 08 PM"
src="https://github.com/bevyengine/bevy/assets/2975848/9cb6f53f-c89a-42c2-8907-b11d294c402a">
On the level of code, these are reflected by two ways of using
`ShapeSample`:
```rust
// Get a single random Vec3:
let sample: Vec3 = match *mode {
Mode::Interior => shape.0.sample_interior(rng),
Mode::Boundary => shape.0.sample_boundary(rng),
};
```
```rust
// Get 100 random Vec3s:
let samples: Vec<Vec3> = match *mode {
Mode::Interior => {
let dist = shape.0.interior_dist();
dist.sample_iter(&mut rng).take(100).collect()
}
Mode::Boundary => {
let dist = shape.0.boundary_dist();
dist.sample_iter(&mut rng).take(100).collect()
}
};
```
## Testing
Run the example!
## Discussion
Maybe in the future it would be nice to show off all of the different
shapes that we have implemented `ShapeSample` for, but I wanted to start
just by demonstrating the functionality. Here, I chose a cube because
it's simple and because it looks good rendered transparently with
backface culling disabled.
This commit, a revamp of #12959, implements screen-space reflections
(SSR), which approximate real-time reflections based on raymarching
through the depth buffer and copying samples from the final rendered
frame. This patch is a relatively minimal implementation of SSR, so as
to provide a flexible base on which to customize and build in the
future. However, it's based on the production-quality [raymarching code
by Tomasz
Stachowiak](https://gist.github.com/h3r2tic/9c8356bdaefbe80b1a22ae0aaee192db).
For a general basic overview of screen-space reflections, see
[1](https://lettier.github.io/3d-game-shaders-for-beginners/screen-space-reflection.html).
The raymarching shader uses the basic algorithm of tracing forward in
large steps, refining that trace in smaller increments via binary
search, and then using the secant method. No temporal filtering or
roughness blurring, is performed at all; for this reason, SSR currently
only operates on very shiny surfaces. No acceleration via the
hierarchical Z-buffer is implemented (though note that
https://github.com/bevyengine/bevy/pull/12899 will add the
infrastructure for this). Reflections are traced at full resolution,
which is often considered slow. All of these improvements and more can
be follow-ups.
SSR is built on top of the deferred renderer and is currently only
supported in that mode. Forward screen-space reflections are possible
albeit uncommon (though e.g. *Doom Eternal* uses them); however, they
require tracing from the previous frame, which would add complexity.
This patch leaves the door open to implementing SSR in the forward
rendering path but doesn't itself have such an implementation.
Screen-space reflections aren't supported in WebGL 2, because they
require sampling from the depth buffer, which Naga can't do because of a
bug (`sampler2DShadow` is incorrectly generated instead of `sampler2D`;
this is the same reason why depth of field is disabled on that
platform).
To add screen-space reflections to a camera, use the
`ScreenSpaceReflectionsBundle` bundle or the
`ScreenSpaceReflectionsSettings` component. In addition to
`ScreenSpaceReflectionsSettings`, `DepthPrepass` and `DeferredPrepass`
must also be present for the reflections to show up. The
`ScreenSpaceReflectionsSettings` component contains several settings
that artists can tweak, and also comes with sensible defaults.
A new example, `ssr`, has been added. It's loosely based on the
[three.js ocean
sample](https://threejs.org/examples/webgl_shaders_ocean.html), but all
the assets are original. Note that the three.js demo has no screen-space
reflections and instead renders a mirror world. In contrast to #12959,
this demo tests not only a cube but also a more complex model (the
flight helmet).
## Changelog
### Added
* Screen-space reflections can be enabled for very smooth surfaces by
adding the `ScreenSpaceReflections` component to a camera. Deferred
rendering must be enabled for the reflections to appear.
