Commit Graph

19 Commits

Author SHA1 Message Date
charlotte 🌸
18712f31f9
Make render and compute pipeline descriptors defaultable. (#19903)
A few versions ago, wgpu made it possible to set shader entry point to
`None`, which will select the correct entry point in file where only a
single entrypoint is specified. This makes it possible to implement
`Default` for pipeline descriptors. This PR does so and attempts to
`..default()` everything possible.
2025-07-02 18:47:27 +00:00
andriyDev
f95f42b44a
Allow calling add_render_graph_node on World. (#19912)
# Objective

- This unblocks some work I am doing for #19887.

## Solution

- Rename `RenderGraphApp` to `RenderGraphExt`.
- Implement `RenderGraphExt` for `World`.
- Change `SubApp` and `App` to call the `World` impl.
2025-07-02 14:56:18 +00:00
atlv
b62b14c293
Add UVec to_extents helper method (#19807)
# Objective

- Simplify common usecase

## Solution

- Helper trait
2025-06-26 20:53:49 +00:00
charlotte 🌸
96dcbc5f8c
Ugrade to wgpu version 25.0 (#19563)
# Objective

Upgrade to `wgpu` version `25.0`.

Depends on https://github.com/bevyengine/naga_oil/pull/121

## Solution

### Problem

The biggest issue we face upgrading is the following requirement:
> To facilitate this change, there was an additional validation rule put
in place: if there is a binding array in a bind group, you may not use
dynamic offset buffers or uniform buffers in that bind group. This
requirement comes from vulkan rules on UpdateAfterBind descriptors.

This is a major difficulty for us, as there are a number of binding
arrays that are used in the view bind group. Note, this requirement does
not affect merely uniform buffors that use dynamic offset but the use of
*any* uniform in a bind group that also has a binding array.

### Attempted fixes

The easiest fix would be to change uniforms to be storage buffers
whenever binding arrays are in use:
```wgsl
#ifdef BINDING_ARRAYS_ARE_USED
@group(0) @binding(0) var<uniform> view: View;
@group(0) @binding(1) var<uniform> lights: types::Lights;
#else
@group(0) @binding(0) var<storage> view: array<View>;
@group(0) @binding(1) var<storage> lights: array<types::Lights>;
#endif
```

This requires passing the view index to the shader so that we know where
to index into the buffer:

```wgsl
struct PushConstants {
    view_index: u32,
}

var<push_constant> push_constants: PushConstants;
```

Using push constants is no problem because binding arrays are only
usable on native anyway.

However, this greatly complicates the ability to access `view` in
shaders. For example:
```wgsl
#ifdef BINDING_ARRAYS_ARE_USED
mesh_view_bindings::view.view_from_world[0].z
#else
mesh_view_bindings::view[mesh_view_bindings::view_index].view_from_world[0].z
#endif
```

Using this approach would work but would have the effect of polluting
our shaders with ifdef spam basically *everywhere*.

Why not use a function? Unfortunately, the following is not valid wgsl
as it returns a binding directly from a function in the uniform path.

```wgsl
fn get_view() -> View {
#if BINDING_ARRAYS_ARE_USED
    let view_index = push_constants.view_index;
    let view = views[view_index];
#endif
    return view;
}
```

This also poses problems for things like lights where we want to return
a ptr to the light data. Returning ptrs from wgsl functions isn't
allowed even if both bindings were buffers.

The next attempt was to simply use indexed buffers everywhere, in both
the binding array and non binding array path. This would be viable if
push constants were available everywhere to pass the view index, but
unfortunately they are not available on webgpu. This means either
passing the view index in a storage buffer (not ideal for such a small
amount of state) or using push constants sometimes and uniform buffers
only on webgpu. However, this kind of conditional layout infects
absolutely everything.

Even if we were to accept just using storage buffer for the view index,
there's also the additional problem that some dynamic offsets aren't
actually per-view but per-use of a setting on a camera, which would
require passing that uniform data on *every* camera regardless of
whether that rendering feature is being used, which is also gross.

As such, although it's gross, the simplest solution just to bump binding
arrays into `@group(1)` and all other bindings up one bind group. This
should still bring us under the device limit of 4 for most users.

### Next steps / looking towards the future

I'd like to avoid needing split our view bind group into multiple parts.
In the future, if `wgpu` were to add `@builtin(draw_index)`, we could
build a list of draw state in gpu processing and avoid the need for any
kind of state change at all (see
https://github.com/gfx-rs/wgpu/issues/6823). This would also provide
significantly more flexibility to handle things like offsets into other
arrays that may not be per-view.

### Testing

Tested a number of examples, there are probably more that are still
broken.

---------

Co-authored-by: François Mockers <mockersf@gmail.com>
Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com>
2025-06-26 19:41:47 +00:00
andriyDev
a7fdd6fc6f
Replace FULLSCREEN_SHADER_HANDLE with a FullscreenShader resource. (#19426)
# Objective

- Related to #19024.

## Solution

- Remove the `FULLSCREEN_SHADER_HANDLE` `weak_handle` with a resource
holding the shader handle.
- This also changes us from using `load_internal_asset` to
`embedded_asset`/`load_embedded_asset`.
- All uses have been migrated to clone the `FullscreenShader` resource
and use its `to_vertex_state` method.

## Testing

- `anti_aliasing` example still works.
- `bloom_3d` example still works.

---------

Co-authored-by: charlotte 🌸 <charlotte.c.mcelwain@gmail.com>
2025-06-24 00:02:23 +00:00
atlv
2915a3b903
rename GlobalTransform::compute_matrix to to_matrix (#19643)
# Objective

- compute_matrix doesn't compute anything, it just puts an Affine3A into
a Mat4. the name is inaccurate

## Solution

- rename it to conform with to_isometry (which, ironically, does compute
a decomposition which is rather expensive)

## Testing

- Its a rename. If it compiles, its good to go

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-06-17 18:37:26 +00:00
Chris Russell
f7e112a3c9
Let query items borrow from query state to avoid needing to clone (#15396)
# Objective

Improve the performance of `FilteredEntity(Ref|Mut)` and
`Entity(Ref|Mut)Except`.

`FilteredEntityRef` needs an `Access<ComponentId>` to determine what
components it can access. There is one stored in the query state, but
query items cannot borrow from the state, so it has to `clone()` the
access for each row. Cloning the access involves memory allocations and
can be expensive.


## Solution

Let query items borrow from their query state.  

Add an `'s` lifetime to `WorldQuery::Item` and `WorldQuery::Fetch`,
similar to the one in `SystemParam`, and provide `&'s Self::State` to
the fetch so that it can borrow from the state.

Unfortunately, there are a few cases where we currently return query
items from temporary query states: the sorted iteration methods create a
temporary state to query the sort keys, and the
`EntityRef::components<Q>()` methods create a temporary state for their
query.

To allow these to continue to work with most `QueryData`
implementations, introduce a new subtrait `ReleaseStateQueryData` that
converts a `QueryItem<'w, 's>` to `QueryItem<'w, 'static>`, and is
implemented for everything except `FilteredEntity(Ref|Mut)` and
`Entity(Ref|Mut)Except`.

`#[derive(QueryData)]` will generate `ReleaseStateQueryData`
implementations that apply when all of the subqueries implement
`ReleaseStateQueryData`.

This PR does not actually change the implementation of
`FilteredEntity(Ref|Mut)` or `Entity(Ref|Mut)Except`! That will be done
as a follow-up PR so that the changes are easier to review. I have
pushed the changes as chescock/bevy#5.

## Testing

I ran performance traces of many_foxes, both against main and against
chescock/bevy#5, both including #15282. These changes do appear to make
generalized animation a bit faster:

(Red is main, yellow is chescock/bevy#5)

![image](https://github.com/user-attachments/assets/de900117-0c6a-431d-ab62-c013834f97a9)


## Migration Guide

The `WorldQuery::Item` and `WorldQuery::Fetch` associated types and the
`QueryItem` and `ROQueryItem` type aliases now have an additional
lifetime parameter corresponding to the `'s` lifetime in `Query`. Manual
implementations of `WorldQuery` will need to update the method
signatures to include the new lifetimes. Other uses of the types will
need to be updated to include a lifetime parameter, although it can
usually be passed as `'_`. In particular, `ROQueryItem` is used when
implementing `RenderCommand`.

Before: 

```rust
fn render<'w>(
    item: &P,
    view: ROQueryItem<'w, Self::ViewQuery>,
    entity: Option<ROQueryItem<'w, Self::ItemQuery>>,
    param: SystemParamItem<'w, '_, Self::Param>,
    pass: &mut TrackedRenderPass<'w>,
) -> RenderCommandResult;
```

After: 

```rust
fn render<'w>(
    item: &P,
    view: ROQueryItem<'w, '_, Self::ViewQuery>,
    entity: Option<ROQueryItem<'w, '_, Self::ItemQuery>>,
    param: SystemParamItem<'w, '_, Self::Param>,
    pass: &mut TrackedRenderPass<'w>,
) -> RenderCommandResult;
```

---

Methods on `QueryState` that take `&mut self` may now result in
conflicting borrows if the query items capture the lifetime of the
mutable reference. This affects `get()`, `iter()`, and others. To fix
the errors, first call `QueryState::update_archetypes()`, and then
replace a call `state.foo(world, param)` with
`state.query_manual(world).foo_inner(param)`. Alternately, you may be
able to restructure the code to call `state.query(world)` once and then
make multiple calls using the `Query`.

Before:
```rust
let mut state: QueryState<_, _> = ...;
let d1 = state.get(world, e1);
let d2 = state.get(world, e2); // Error: cannot borrow `state` as mutable more than once at a time
println!("{d1:?}");
println!("{d2:?}");
```

After: 
```rust
let mut state: QueryState<_, _> = ...;

state.update_archetypes(world);
let d1 = state.get_manual(world, e1);
let d2 = state.get_manual(world, e2);
// OR
state.update_archetypes(world);
let d1 = state.query(world).get_inner(e1);
let d2 = state.query(world).get_inner(e2);
// OR
let query = state.query(world);
let d1 = query.get_inner(e1);
let d1 = query.get_inner(e2);

println!("{d1:?}");
println!("{d2:?}");
```
2025-06-16 21:05:41 +00:00
andriyDev
b866bb4254
Remove Shader weak_handles from bevy_pbr (excluding meshlets). (#19365)
# Objective

- Related to #19024

## Solution

- Use the new `load_shader_library` macro for the shader libraries and
`embedded_asset`/`load_embedded_asset` for the "shader binaries" in
`bevy_pbr` (excluding meshlets).

## Testing

- `atmosphere` example still works
- `fog` example still works
- `decal` example still works

P.S. I don't think this needs a migration guide. Technically users could
be using the `pub` weak handles, but there's no actual good use for
them, so omitting it seems fine. Alternatively, we could mix this in
with the migration guide notes for #19137.
2025-05-27 22:32:47 +00:00
Emerson Coskey
7ab00ca185
Split Camera.hdr out into a new component (#18873)
# Objective

- Simplify `Camera` initialization
- allow effects to require HDR

## Solution

- Split out `Camera.hdr` into a marker `Hdr` component

## Testing

- ran `bloom_3d` example

---

## Showcase

```rs
// before
commands.spawn((
  Camera3d
  Camera {
    hdr: true
    ..Default::default()
  }
))

// after
commands.spawn((Camera3d, Hdr));

// other rendering components can require that the camera enables hdr!
// currently implemented for Bloom, AutoExposure, and Atmosphere.
#[require(Hdr)]
pub struct Bloom;
```
2025-05-26 19:24:45 +00:00
Joona Aalto
7b1c9f192e
Adopt consistent FooSystems naming convention for system sets (#18900)
# Objective

Fixes a part of #14274.

Bevy has an incredibly inconsistent naming convention for its system
sets, both internally and across the ecosystem.

<img alt="System sets in Bevy"
src="https://github.com/user-attachments/assets/d16e2027-793f-4ba4-9cc9-e780b14a5a1b"
width="450" />

*Names of public system set types in Bevy*

Most Bevy types use a naming of `FooSystem` or just `Foo`, but there are
also a few `FooSystems` and `FooSet` types. In ecosystem crates on the
other hand, `FooSet` is perhaps the most commonly used name in general.
Conventions being so wildly inconsistent can make it harder for users to
pick names for their own types, to search for system sets on docs.rs, or
to even discern which types *are* system sets.

To reign in the inconsistency a bit and help unify the ecosystem, it
would be good to establish a common recommended naming convention for
system sets in Bevy itself, similar to how plugins are commonly suffixed
with `Plugin` (ex: `TimePlugin`). By adopting a consistent naming
convention in first-party Bevy, we can softly nudge ecosystem crates to
follow suit (for types where it makes sense to do so).

Choosing a naming convention is also relevant now, as the [`bevy_cli`
recently adopted
lints](https://github.com/TheBevyFlock/bevy_cli/pull/345) to enforce
naming for plugins and system sets, and the recommended naming used for
system sets is still a bit open.

## Which Name To Use?

Now the contentious part: what naming convention should we actually
adopt?

This was discussed on the Bevy Discord at the end of last year, starting
[here](<https://discord.com/channels/691052431525675048/692572690833473578/1310659954683936789>).
`FooSet` and `FooSystems` were the clear favorites, with `FooSet` very
narrowly winning an unofficial poll. However, it seems to me like the
consensus was broadly moving towards `FooSystems` at the end and after
the poll, with Cart
([source](https://discord.com/channels/691052431525675048/692572690833473578/1311140204974706708))
and later Alice
([source](https://discord.com/channels/691052431525675048/692572690833473578/1311092530732859533))
and also me being in favor of it.

Let's do a quick pros and cons list! Of course these are just what I
thought of, so take it with a grain of salt.

`FooSet`:

- Pro: Nice and short!
- Pro: Used by many ecosystem crates.
- Pro: The `Set` suffix comes directly from the trait name `SystemSet`.
- Pro: Pairs nicely with existing APIs like `in_set` and
`configure_sets`.
- Con: `Set` by itself doesn't actually indicate that it's related to
systems *at all*, apart from the implemented trait. A set of what?
- Con: Is `FooSet` a set of `Foo`s or a system set related to `Foo`? Ex:
`ContactSet`, `MeshSet`, `EnemySet`...

`FooSystems`:

- Pro: Very clearly indicates that the type represents a collection of
systems. The actual core concept, system(s), is in the name.
- Pro: Parallels nicely with `FooPlugins` for plugin groups.
- Pro: Low risk of conflicts with other names or misunderstandings about
what the type is.
- Pro: In most cases, reads *very* nicely and clearly. Ex:
`PhysicsSystems` and `AnimationSystems` as opposed to `PhysicsSet` and
`AnimationSet`.
- Pro: Easy to search for on docs.rs.
- Con: Usually results in longer names.
- Con: Not yet as widely used.

Really the big problem with `FooSet` is that it doesn't actually
describe what it is. It describes what *kind of thing* it is (a set of
something), but not *what it is a set of*, unless you know the type or
check its docs or implemented traits. `FooSystems` on the other hand is
much more self-descriptive in this regard, at the cost of being a bit
longer to type.

Ultimately, in some ways it comes down to preference and how you think
of system sets. Personally, I was originally in favor of `FooSet`, but
have been increasingly on the side of `FooSystems`, especially after
seeing what the new names would actually look like in Avian and now
Bevy. I prefer it because it usually reads better, is much more clearly
related to groups of systems than `FooSet`, and overall *feels* more
correct and natural to me in the long term.

For these reasons, and because Alice and Cart also seemed to share a
preference for it when it was previously being discussed, I propose that
we adopt a `FooSystems` naming convention where applicable.

## Solution

Rename Bevy's system set types to use a consistent `FooSet` naming where
applicable.

- `AccessibilitySystem` → `AccessibilitySystems`
- `GizmoRenderSystem` → `GizmoRenderSystems`
- `PickSet` → `PickingSystems`
- `RunFixedMainLoopSystem` → `RunFixedMainLoopSystems`
- `TransformSystem` → `TransformSystems`
- `RemoteSet` → `RemoteSystems`
- `RenderSet` → `RenderSystems`
- `SpriteSystem` → `SpriteSystems`
- `StateTransitionSteps` → `StateTransitionSystems`
- `RenderUiSystem` → `RenderUiSystems`
- `UiSystem` → `UiSystems`
- `Animation` → `AnimationSystems`
- `AssetEvents` → `AssetEventSystems`
- `TrackAssets` → `AssetTrackingSystems`
- `UpdateGizmoMeshes` → `GizmoMeshSystems`
- `InputSystem` → `InputSystems`
- `InputFocusSet` → `InputFocusSystems`
- `ExtractMaterialsSet` → `MaterialExtractionSystems`
- `ExtractMeshesSet` → `MeshExtractionSystems`
- `RumbleSystem` → `RumbleSystems`
- `CameraUpdateSystem` → `CameraUpdateSystems`
- `ExtractAssetsSet` → `AssetExtractionSystems`
- `Update2dText` → `Text2dUpdateSystems`
- `TimeSystem` → `TimeSystems`
- `AudioPlaySet` → `AudioPlaybackSystems`
- `SendEvents` → `EventSenderSystems`
- `EventUpdates` → `EventUpdateSystems`

A lot of the names got slightly longer, but they are also a lot more
consistent, and in my opinion the majority of them read much better. For
a few of the names I took the liberty of rewording things a bit;
definitely open to any further naming improvements.

There are still also cases where the `FooSystems` naming doesn't really
make sense, and those I left alone. This primarily includes system sets
like `Interned<dyn SystemSet>`, `EnterSchedules<S>`, `ExitSchedules<S>`,
or `TransitionSchedules<S>`, where the type has some special purpose and
semantics.

## Todo

- [x] Should I keep all the old names as deprecated type aliases? I can
do this, but to avoid wasting work I'd prefer to first reach consensus
on whether these renames are even desired.
- [x] Migration guide
- [x] Release notes
2025-05-06 15:18:03 +00:00
Máté Homolya
a616ffa8ac
Web support for atmosphere (#18582)
# Objective

Add web support to atmosphere by gating dual source blending and using a
macro to determine the target platform.
The main objective of this PR is to ensure that users of Bevy's
atmosphere feature can also run it in a web-based context where WebGPU
support is enabled.

## Solution

- Make use of the `#[cfg(not(target_arch = "wasm32"))]` macro to gate
the dual source blending, as this is not (yet) supported in web
browsers.
- Rename the function `sample_sun_illuminance` to `sample_sun_radiance`
and move calls out of conditionals to ensure the shader compiles and
runs in both native and web-based contexts.
- Moved the multiplication of the transmittance out when calculating the
sun color, because calling the `sample_sun_illuminance` function was
causing issues in web. Overall this results in cleaner code and more
readable.

## Testing

- Tested by building a wasm target and loading it in a web page with
Vite dev server using `mate-h/bevy-webgpu` repo template.
- Tested the native build with `cargo run --example atmosphere` to
ensure it still works with dual source blending.

---

## Showcase

Screenshots show the atmosphere example running in two different
contexts:

<img width="1281" alt="atmosphere-web-showcase"
src="https://github.com/user-attachments/assets/40b1ee91-89ae-41a6-8189-89630d1ca1a6"
/>

---------

Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2025-04-06 20:06:55 +00:00
Martín Maita
5973ba418f
Bump crate-ci/typos from 1.30.2 to 1.31.0 (#18656)
# Objective

- Fixes #18642

## Solution

- Bumped crate-ci/typos from 1.30.2 to 1.31.0.
- Fixed typos.

## Testing

- Typos were fixed.

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2025-04-02 10:59:15 +00:00
Gino Valente
9b32e09551
bevy_reflect: Add clone registrations project-wide (#18307)
# Objective

Now that #13432 has been merged, it's important we update our reflected
types to properly opt into this feature. If we do not, then this could
cause issues for users downstream who want to make use of
reflection-based cloning.

## Solution

This PR is broken into 4 commits:

1. Add `#[reflect(Clone)]` on all types marked `#[reflect(opaque)]` that
are also `Clone`. This is mandatory as these types would otherwise cause
the cloning operation to fail for any type that contains it at any
depth.
2. Update the reflection example to suggest adding `#[reflect(Clone)]`
on opaque types.
3. Add `#[reflect(clone)]` attributes on all fields marked
`#[reflect(ignore)]` that are also `Clone`. This prevents the ignored
field from causing the cloning operation to fail.
   
Note that some of the types that contain these fields are also `Clone`,
and thus can be marked `#[reflect(Clone)]`. This makes the
`#[reflect(clone)]` attribute redundant. However, I think it's safer to
keep it marked in the case that the `Clone` impl/derive is ever removed.
I'm open to removing them, though, if people disagree.
4. Finally, I added `#[reflect(Clone)]` on all types that are also
`Clone`. While not strictly necessary, it enables us to reduce the
generated output since we can just call `Clone::clone` directly instead
of calling `PartialReflect::reflect_clone` on each variant/field. It
also means we benefit from any optimizations or customizations made in
the `Clone` impl, including directly dereferencing `Copy` values and
increasing reference counters.

Along with that change I also took the liberty of adding any missing
registrations that I saw could be applied to the type as well, such as
`Default`, `PartialEq`, and `Hash`. There were hundreds of these to
edit, though, so it's possible I missed quite a few.

That last commit is **_massive_**. There were nearly 700 types to
update. So it's recommended to review the first three before moving onto
that last one.

Additionally, I can break the last commit off into its own PR or into
smaller PRs, but I figured this would be the easiest way of doing it
(and in a timely manner since I unfortunately don't have as much time as
I used to for code contributions).

## Testing

You can test locally with a `cargo check`:

```
cargo check --workspace --all-features
```
2025-03-17 18:32:35 +00:00
newclarityex
ecccd57417
Generic system config (#17962)
# Objective
Prevents duplicate implementation between IntoSystemConfigs and
IntoSystemSetConfigs using a generic, adds a NodeType trait for more
config flexibility (opening the door to implement
https://github.com/bevyengine/bevy/issues/14195?).

## Solution
Followed writeup by @ItsDoot:
https://hackmd.io/@doot/rJeefFHc1x

Removes IntoSystemConfigs and IntoSystemSetConfigs, instead using
IntoNodeConfigs with generics.

## Testing
Pending

---

## Showcase
N/A

## Migration Guide
SystemSetConfigs -> NodeConfigs<InternedSystemSet>
SystemConfigs -> NodeConfigs<ScheduleSystem>
IntoSystemSetConfigs -> IntoNodeConfigs<InternedSystemSet, M>
IntoSystemConfigs -> IntoNodeConfigs<ScheduleSystem, M>

---------

Co-authored-by: Christian Hughes <9044780+ItsDoot@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2025-03-12 00:12:30 +00:00
Carter Anderson
06cb5c5fd9
Fix Component require() IDE integration (#18165)
# Objective

Component `require()` IDE integration is fully broken, as of #16575.

## Solution

This reverts us back to the previous "put the docs on Component trait"
impl. This _does_ reduce the accessibility of the required components in
rust docs, but the complete erasure of "required component IDE
experience" is not worth the price of slightly increased prominence of
requires in docs.

Additionally, Rust Analyzer has recently started including derive
attributes in suggestions, so we aren't losing that benefit of the
proc_macro attribute impl.
2025-03-06 02:44:47 +00:00
Emerson Coskey
83370e0a25
Use dual-source blending for rendering the sky (#17672)
# Objective

Since previously we only had the alpha channel available, we stored the
mean of the transmittance in the aerial view lut, resulting in a grayer
fog than should be expected.

## Solution

- Calculate transmittance to scene in `render_sky` with two samples from
the transmittance lut
- use dual-source blending to effectively have per-component alpha
blending
2025-02-10 23:53:53 +00:00
Sludge
989f547080
Weak handle migration (#17695)
# Objective

- Make use of the new `weak_handle!` macro added in
https://github.com/bevyengine/bevy/pull/17384

## Solution

- Migrate bevy from `Handle::weak_from_u128` to the new `weak_handle!`
macro that takes a random UUID
- Deprecate `Handle::weak_from_u128`, since there are no remaining use
cases that can't also be addressed by constructing the type manually

## Testing

- `cargo run -p ci -- test`

---

## Migration Guide

Replace `Handle::weak_from_u128` with `weak_handle!` and a random UUID.
2025-02-05 22:44:20 +00:00
Máté Homolya
f22ea72db0
Atmosphere LUT parameterization improvements (#17555)
# Objective

- Fix the atmosphere LUT parameterization in the aerial -view and
sky-view LUTs
- Correct the light accumulation according to a ray-marched reference
- Avoid negative values of the sun disk illuminance when the sun disk is
below the horizon

## Solution

- Adding a Newton's method iteration to `fast_sqrt` function
- Switched to using `fast_acos_4` for better precision of the sun angle
towards the horizon (view mu angle = 0)
- Simplified the function for mapping to and from the Sky View UV
coordinates by removing an if statement and correctly apply the method
proposed by the [Hillarie
paper](https://sebh.github.io/publications/egsr2020.pdf) detailed in
section 5.3 and 5.4.
- Replaced the `ray_dir_ws.y` term with a shadow factor in the
`sample_sun_illuminance` function that correctly approximates the sun
disk occluded by the earth from any view point

## Testing

- Ran the atmosphere and SSAO examples to make sure the shaders still
compile and run as expected.

---

## Showcase

<img width="1151" alt="showcase-img"
src="https://github.com/user-attachments/assets/de875533-42bd-41f9-9fd0-d7cc57d6e51c"
/>

---------

Co-authored-by: Emerson Coskey <emerson@coskey.dev>
2025-02-03 21:52:11 +00:00
Emerson Coskey
81a25bb0c7
Procedural atmospheric scattering (#16314)
Implement procedural atmospheric scattering from [Sebastien Hillaire's
2020 paper](https://sebh.github.io/publications/egsr2020.pdf). This
approach should scale well even down to mobile hardware, and is
physically accurate.

## Co-author: @mate-h 

He helped massively with getting this over the finish line, ensuring
everything was physically correct, correcting several places where I had
misunderstood or misapplied the paper, and improving the performance in
several places as well. Thanks!

## Credits

@aevyrie: helped find numerous bugs and improve the example to best show
off this feature :)

Built off of @mtsr's original branch, which handled the transmittance
lut (arguably the most important part)

## Showcase: 


![sunset](https://github.com/user-attachments/assets/2eee1f38-f66d-4772-bb72-163e13c719d8)

![twilight](https://github.com/user-attachments/assets/f7d358b6-898d-4df7-becc-188cd753102d)


## For followup

- Integrate with pcwalton's volumetrics code
- refactor/reorganize for better integration with other effects
- have atmosphere transmittance affect directional lights
- add support for generating skybox/environment map

---------

Co-authored-by: Emerson Coskey <56370779+EmersonCoskey@users.noreply.github.com>
Co-authored-by: atlv <email@atlasdostal.com>
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
Co-authored-by: Emerson Coskey <coskey@emerlabs.net>
Co-authored-by: Máté Homolya <mate.homolya@gmail.com>
2025-01-23 22:52:46 +00:00