Commit graph

89 commits

Author SHA1 Message Date
Nicola Papale
83de94f9f9
Register a few missed reflect components (#8807)
# Objective

-  Some reflect components weren't properly registered.

## Solution

- We register them
- I also sorted the register lines in `Plugin::build` in `bevy_ui`

### Note

How I did I find them:

- I picked up the list of `Component`s from the `Component` trait page
in rustdoc.
- Then I tried to register all of them. Removing the registration when
it doesn't implement `Reflect` to pass compilation.
- Then I added `app.register_type_data::<T, Foo>()`, for all Reflect
components. It panics if `T` is not registered.
- I repeated the last line N times until bevy stopped panicking at
startup

---

## Changelog

- Register the following components: `PrimaryWindow` `Fxaa`
`FogSettings` `NotShadowCaster` `NotShadowReceiver` `CalculatedClip`
`RelativeCursorPosition`
2023-06-10 23:19:39 +00:00
Alice Cecile
cbd4abf0fc
Rename apply_system_buffers to apply_deferred (#8726)
# Objective

- `apply_system_buffers` is an unhelpful name: it introduces a new
internal-only concept
- this is particularly rough for beginners as reasoning about how
commands work is a critical stumbling block

## Solution

- rename `apply_system_buffers` to the more descriptive `apply_deferred`
- rename related fields, arguments and methods in the internals fo
bevy_ecs for consistency
- update the docs


## Changelog

`apply_system_buffers` has been renamed to `apply_deferred`, to more
clearly communicate its intent and relation to `Deferred` system
parameters like `Commands`.

## Migration Guide

- `apply_system_buffers` has been renamed to `apply_deferred`
- the `apply_system_buffers` method on the `System` trait has been
renamed to `apply_deferred`
- the `is_apply_system_buffers` function has been replaced by
`is_apply_deferred`
- `Executor::set_apply_final_buffers` is now
`Executor::set_apply_final_deferred`
- `Schedule::apply_system_buffers` is now `Schedule::apply_deferred`

---------

Co-authored-by: JoJoJet <21144246+JoJoJet@users.noreply.github.com>
2023-06-02 14:04:13 +00:00
François
71842c5ac9
Webgpu support (#8336)
# Objective

- Support WebGPU
- alternative to #5027 that doesn't need any async / await
- fixes #8315 
- Surprise fix #7318

## Solution

### For async renderer initialisation 

- Update the plugin lifecycle:
  - app builds the plugin
    - calls `plugin.build`
    - registers the plugin
  - app starts the event loop
- event loop waits for `ready` of all registered plugins in the same
order
    - returns `true` by default
- then call all `finish` then all `cleanup` in the same order as
registered
  - then execute the schedule

In the case of the renderer, to avoid anything async:
- building the renderer plugin creates a detached task that will send
back the initialised renderer through a mutex in a resource
- `ready` will wait for the renderer to be present in the resource
- `finish` will take that renderer and place it in the expected
resources by other plugins
- other plugins (that expect the renderer to be available) `finish` are
called and they are able to set up their pipelines
- `cleanup` is called, only custom one is still for pipeline rendering

### For WebGPU support

- update the `build-wasm-example` script to support passing `--api
webgpu` that will build the example with WebGPU support
- feature for webgl2 was always enabled when building for wasm. it's now
in the default feature list and enabled on all platforms, so check for
this feature must also check that the target_arch is `wasm32`

---

## Migration Guide

- `Plugin::setup` has been renamed `Plugin::cleanup`
- `Plugin::finish` has been added, and plugins adding pipelines should
do it in this function instead of `Plugin::build`
```rust
// Before
impl Plugin for MyPlugin {
    fn build(&self, app: &mut App) {
        app.insert_resource::<MyResource>
            .add_systems(Update, my_system);

        let render_app = match app.get_sub_app_mut(RenderApp) {
            Ok(render_app) => render_app,
            Err(_) => return,
        };

        render_app
            .init_resource::<RenderResourceNeedingDevice>()
            .init_resource::<OtherRenderResource>();
    }
}

// After
impl Plugin for MyPlugin {
    fn build(&self, app: &mut App) {
        app.insert_resource::<MyResource>
            .add_systems(Update, my_system);
    
        let render_app = match app.get_sub_app_mut(RenderApp) {
            Ok(render_app) => render_app,
            Err(_) => return,
        };
    
        render_app
            .init_resource::<OtherRenderResource>();
    }

    fn finish(&self, app: &mut App) {
        let render_app = match app.get_sub_app_mut(RenderApp) {
            Ok(render_app) => render_app,
            Err(_) => return,
        };
    
        render_app
            .init_resource::<RenderResourceNeedingDevice>();
    }
}
```
2023-05-04 22:07:57 +00:00
Nicola Papale
8df014fbaf
Add parallax mapping to bevy PBR (#5928)
# Objective

Add a [parallax mapping] shader to bevy. Please note that
this is a 3d technique, NOT a 2d sidescroller feature.

## Solution

- Add related fields to `StandardMaterial`
- update the pbr shader
- Add an example taking advantage of parallax mapping

A pre-existing implementation exists at:
https://github.com/nicopap/bevy_mod_paramap/

The implementation is derived from:

https://web.archive.org/web/20150419215321/http://sunandblackcat.com/tipFullView.php?l=eng&topicid=28

Further discussion on literature is found in the `bevy_mod_paramap`
README.

### Limitations

- The mesh silhouette isn't affected by the depth map.
- The depth of the pixel does not reflect its visual position, resulting
  in artifacts for depth-dependent features such as fog or SSAO
- GLTF does not define a height map texture, so somehow the user will
  always need to work around this limitation, though [an extension is in
  the works][gltf]

### Future work

- It's possible to update the depth in the depth buffer to follow the
  parallaxed texture. This would enable interop with depth-based
  visual effects, it also allows `discard`ing pixels of materials when
  computed depth is higher than the one in depth buffer
- Cheap lower quality single-sample method using [offset limiting]
- Add distance fading, to disable parallaxing (relatively expensive)
  on distant objects
- GLTF extension to allow defining height maps. Or a workaround
  implemented through a blender plugin to the GLTF exporter that
  uses the `extras` field to add height map.
- [Quadratic surface vertex attributes][oliveira_3] to enable parallax
  mapping on bending surfaces and allow clean silhouetting.
- noise based sampling, to limit the pancake artifacts.
- Cone mapping ([GPU gems], [Simcity (2013)][simcity]). Requires
  preprocessing, increase depth map size, reduces sample count greatly.
- [Quadtree parallax mapping][qpm] (also requires preprocessing)
- Self-shadowing of parallax-mapped surfaces by modifying the shadow map
- Generate depth map from normal map [link to slides], [blender
question]


https://user-images.githubusercontent.com/26321040/223563792-dffcc6ab-70e8-4ff9-90d1-b36c338695ad.mp4

[blender question]:
https://blender.stackexchange.com/questions/89278/how-to-get-a-smooth-curvature-map-from-a-normal-map
[link to slides]:
https://developer.download.nvidia.com/assets/gamedev/docs/nmap2displacement.pdf
[oliveira_3]:
https://www.inf.ufrgs.br/~oliveira/pubs_files/Oliveira_Policarpo_RP-351_Jan_2005.pdf
[GPU gems]:
https://developer.nvidia.com/gpugems/gpugems3/part-iii-rendering/chapter-18-relaxed-cone-stepping-relief-mapping
[simcity]:
https://community.simtropolis.com/omnibus/other-games/building-and-rendering-simcity-2013-r247/
[offset limiting]:
https://raw.githubusercontent.com/marcusstenbeck/tncg14-parallax-mapping/master/documents/Parallax%20Mapping%20with%20Offset%20Limiting%20-%20A%20Per-Pixel%20Approximation%20of%20Uneven%20Surfaces.pdf
[gltf]: https://github.com/KhronosGroup/glTF/pull/2196
[qpm]:
https://www.gamedevs.org/uploads/quadtree-displacement-mapping-with-height-blending.pdf

---

## Changelog

- Add a `depth_map` field to the `StandardMaterial`, it is a grayscale
  image where white represents bottom and black the top. If `depth_map`
  is set, bevy's pbr shader will use it to do [parallax mapping] to
  give an increased feel of depth to the material. This is similar to a
  displacement map, but with infinite precision at fairly low cost.
- The fields `parallax_mapping_method`, `parallax_depth_scale` and
  `max_parallax_layer_count` allow finer grained control over the
  behavior of the parallax shader.
- Add the `parallax_mapping` example to show off the effect.

[parallax mapping]: https://en.wikipedia.org/wiki/Parallax_mapping

---------

Co-authored-by: Robert Swain <robert.swain@gmail.com>
2023-04-15 10:25:14 +00:00
JoJoJet
3ead10a3e0
Suppress the clippy::type_complexity lint (#8313)
# Objective

The clippy lint `type_complexity` is known not to play well with bevy.
It frequently triggers when writing complex queries, and taking the
lint's advice of using a type alias almost always just obfuscates the
code with no benefit. Because of this, this lint is currently ignored in
CI, but unfortunately it still shows up when viewing bevy code in an
IDE.

As someone who's made a fair amount of pull requests to this repo, I
will say that this issue has been a consistent thorn in my side. Since
bevy code is filled with spurious, ignorable warnings, it can be very
difficult to spot the *real* warnings that must be fixed -- most of the
time I just ignore all warnings, only to later find out that one of them
was real after I'm done when CI runs.

## Solution

Suppress this lint in all bevy crates. This was previously attempted in
#7050, but the review process ended up making it more complicated than
it needs to be and landed on a subpar solution.

The discussion in https://github.com/rust-lang/rust-clippy/pull/10571
explores some better long-term solutions to this problem. Since there is
no timeline on when these solutions may land, we should resolve this
issue in the meantime by locally suppressing these lints.

### Unresolved issues

Currently, these lints are not suppressed in our examples, since that
would require suppressing the lint in every single source file. They are
still ignored in CI.
2023-04-06 21:27:36 +00:00
James O'Brien
ae31361949
Split opaque and transparent phases (#8090)
# Objective

Fixes #8089. 

## Solution

Splits the MainPass3dNode into 2 nodes, one for the opaque + alpha
passes and one for the transparent pass.

---

## Changelog
- Split MainPass3dNode into MainOpaquePass3dNode and
MainTransparentPass3dNode
- Combine opaque and alpha phases in MainOpaquePass3dNode into one pass
- Create `START_MAIN_PASS` and `END_MAIN_PASS` empty nodes as labels
- Main pass becomes `START_MAIN_PASS -> MAIN_OPAQUE_PASS ->
MAIN_TRANSPARENT_PASS -> END_MAIN_PASS`

## Migration Guide

Nodes that previously added edges involving `MAIN_PASS` should now add
edges to or from `START_MAIN_PASS` or `END_MAIN_PASS` respectively.
2023-03-28 06:35:16 +00:00
IceSentry
2c21d423fd
Make render graph slots optional for most cases (#8109)
# Objective

- Currently, the render graph slots are only used to pass the
view_entity around. This introduces significant boilerplate for very
little value. Instead of using slots for this, make the view_entity part
of the `RenderGraphContext`. This also means we won't need to have
`IN_VIEW` on every node and and we'll be able to use the default impl of
`Node::input()`.

## Solution

- Add `view_entity: Option<Entity>` to the `RenderGraphContext`
- Update all nodes to use this instead of entity slot input

---

## Changelog

- Add optional `view_entity` to `RenderGraphContext`

## Migration Guide

You can now get the view_entity directly from the `RenderGraphContext`. 

When implementing the Node:

```rust
// 0.10
struct FooNode;
impl FooNode {
    const IN_VIEW: &'static str = "view";
}
impl Node for FooNode {
    fn input(&self) -> Vec<SlotInfo> {
        vec![SlotInfo::new(Self::IN_VIEW, SlotType::Entity)]
    }
    fn run(
        &self,
        graph: &mut RenderGraphContext,
        // ... 
    ) -> Result<(), NodeRunError> {
        let view_entity = graph.get_input_entity(Self::IN_VIEW)?;
        // ...
        Ok(())
    }
}

// 0.11
struct FooNode;
impl Node for FooNode {
    fn run(
        &self,
        graph: &mut RenderGraphContext,
        // ... 
    ) -> Result<(), NodeRunError> {
        let view_entity = graph.view_entity();
        // ...
        Ok(())
    }
}
```

When adding the node to the graph, you don't need to specify a slot_edge
for the view_entity.

```rust
// 0.10
let mut graph = RenderGraph::default();
graph.add_node(FooNode::NAME, node);
let input_node_id = draw_2d_graph.set_input(vec![SlotInfo::new(
    graph::input::VIEW_ENTITY,
    SlotType::Entity,
)]);
graph.add_slot_edge(
    input_node_id,
    graph::input::VIEW_ENTITY,
    FooNode::NAME,
    FooNode::IN_VIEW,
);
// add_node_edge ...

// 0.11
let mut graph = RenderGraph::default();
graph.add_node(FooNode::NAME, node);
// add_node_edge ...
```

## Notes

This PR paired with #8007 will help reduce a lot of annoying boilerplate
with the render nodes. Depending on which one gets merged first. It will
require a bit of clean up work to make both compatible.

I tagged this as a breaking change, because using the old system to get
the view_entity will break things because it's not a node input slot
anymore.

## Notes for reviewers

A lot of the diffs are just removing the slots in every nodes and graph
creation. The important part is mostly in the
graph_runner/CameraDriverNode.
2023-03-21 20:11:13 +00:00
Carter Anderson
aefe1f0739
Schedule-First: the new and improved add_systems (#8079)
Co-authored-by: Mike <mike.hsu@gmail.com>
2023-03-18 01:45:34 +00:00
BlondeBurrito
602f3baf3f
fix: register Cascade in the TypeRegistry (#8088) 2023-03-15 00:11:55 +00:00
JoJoJet
fd1af7c8b8
Replace multiple calls to add_system with add_systems (#8001) 2023-03-10 18:15:22 +00:00
Edgar Geier
e54103fd69 Use prepass shaders for shadows (#7784)
# Objective

- Fixes #4372.

## Solution

- Use the prepass shaders for the shadow passes.
- Move `DEPTH_CLAMP_ORTHO` from `ShadowPipelineKey` to `MeshPipelineKey` and the associated clamp operation from `depth.wgsl` to `prepass.wgsl`.
- Remove `depth.wgsl` .
- Replace `ShadowPipeline` with `ShadowSamplers`.

Instead of running the custom `ShadowPipeline` we run the `PrepassPipeline` with the `DEPTH_PREPASS` flag and additionally the `DEPTH_CLAMP_ORTHO` flag for directional lights as well as the `ALPHA_MASK` flag for materials that use `AlphaMode::Mask(_)`.
2023-03-02 08:21:21 +00:00
JoJoJet
b8263b55fb Support system.in_schedule() and system.on_startup() (#7790)
# Objective

Support the following syntax for adding systems:

```rust
App::new()
    .add_system(setup.on_startup())
    .add_systems((
        show_menu.in_schedule(OnEnter(GameState::Paused)),
        menu_ssytem.in_set(OnUpdate(GameState::Paused)),
        hide_menu.in_schedule(OnExit(GameState::Paused)),
    ))
```

## Solution

Add the traits `IntoSystemAppConfig{s}`, which provide the extension methods necessary for configuring which schedule a system belongs to. These extension methods return `IntoSystemAppConfig{s}`, which `App::add_system{s}` uses to choose which schedule to add systems to.

---

## Changelog

+ Added the extension methods `in_schedule(label)` and  `on_startup()` for configuring the schedule a system belongs to.

## Future Work

* Replace all uses of `add_startup_system` in the engine.
* Deprecate this method
2023-02-24 18:33:55 +00:00
Mike
cd447fb4e6 Cleanup render schedule (#7589)
# Objective

- Fixes https://github.com/bevyengine/bevy/issues/7531

## Solution

- Add systems to prepare set
- Also remove a unnecessary apply_systems_buffers from ExtractCommands set.
2023-02-10 03:32:54 +00:00
JMS55
dd4299bcf9 EnvironmentMapLight, BRDF Improvements (#7051)
(Before)
![image](https://user-images.githubusercontent.com/47158642/213946111-15ec758f-1f1d-443c-b196-1fdcd4ae49da.png)
(After)
![image](https://user-images.githubusercontent.com/47158642/217051179-67381e73-dd44-461b-a2c7-87b0440ef8de.png)
![image](https://user-images.githubusercontent.com/47158642/212492404-524e4ad3-7837-4ed4-8b20-2abc276aa8e8.png)

# Objective
- Improve lighting; especially reflections.
- Closes https://github.com/bevyengine/bevy/issues/4581.

## Solution
- Implement environment maps, providing better ambient light.
- Add microfacet multibounce approximation for specular highlights from Filament.
- Occlusion is no longer incorrectly applied to direct lighting. It now only applies to diffuse indirect light. Unsure if it's also supposed to apply to specular indirect light - the glTF specification just says "indirect light". In the case of ambient occlusion, for instance, that's usually only calculated as diffuse though. For now, I'm choosing to apply this just to indirect diffuse light, and not specular.
- Modified the PBR example to use an environment map, and have labels.
- Added `FallbackImageCubemap`.

## Implementation
- IBL technique references can be found in environment_map.wgsl.
- It's more accurate to use a LUT for the scale/bias. Filament has a good reference on generating this LUT. For now, I just used an analytic approximation.
 - For now, environment maps must first be prefiltered outside of bevy using a 3rd party tool. See the `EnvironmentMap` documentation.
- Eventually, we should have our own prefiltering code, so that we can have dynamically changing environment maps, as well as let users drop in an HDR image and use asset preprocessing to create the needed textures using only bevy. 

---

## Changelog
- Added an `EnvironmentMapLight` camera component that adds additional ambient light to a scene.
- StandardMaterials will now appear brighter and more saturated at high roughness, due to internal material changes. This is more physically correct.
- Fixed StandardMaterial occlusion being incorrectly applied to direct lighting.
- Added `FallbackImageCubemap`.

Co-authored-by: IceSentry <c.giguere42@gmail.com>
Co-authored-by: James Liu <contact@jamessliu.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
2023-02-09 16:46:32 +00:00
ira
f69f1329e0 Fix Window feedback loop between the OS and Bevy (#7517)
# Objective

Fix #7377
Fix #7513

## Solution

Record the changes made to the Bevy `Window` from `winit` as 'canon' to avoid Bevy sending those changes back to `winit` again, causing a feedback loop.

## Changelog

* Removed `ModifiesWindows` system label.
  Neither `despawn_window` nor `changed_window` actually modify the `Window` component so all the `.after(ModifiesWindows)` shouldn't be necessary.
* Moved `changed_window` and `despawn_window` systems to `CoreStage::Last` to avoid systems making changes to the `Window` between `changed_window` and the end of the frame as they would be ignored.

## Migration Guide
The `ModifiesWindows` system label was removed.


Co-authored-by: devil-ira <justthecooldude@gmail.com>
2023-02-07 14:18:13 +00:00
robtfm
ea2ecd4f75 add ambient lighting hook (#5428)
# Objective

add a hook for ambient occlusion to the pbr shader

## Solution

add a hook for ambient occlusion to the pbr shader


Co-authored-by: atlas dostal <rodol@rivalrebels.com>
2023-02-07 00:41:18 +00:00
Jakob Hellermann
2e20d04f32 use better set inheritance in render systems (#7524)
# Objective
Some render systems that have system set used as a label so that they can be referenced from somewhere else.
The 1:1 translation from `add_system_to_stage(Prepare, prepare_lights.label(PrepareLights))` is `add_system(prepare_lights.in_set(Prepare).in_set(PrepareLights)`, but configuring the `PrepareLights` set to be in `Prepare` would match the intention better (there are no systems in `PrepareLights` outside of `Prepare`) and it is easier for visualization tools to deal with.

# Solution

- replace
```rust
prepare_lights in PrepareLights
prepare_lights in Prepare
```
with
```rs
prepare_lights in PrepareLights
PrepareLights in Prepare
```

**Before**
![before](https://user-images.githubusercontent.com/22177966/216961792-a0f5eba7-f161-4994-b5a4-33e98763a3b0.svg)

**After**
![after](https://user-images.githubusercontent.com/22177966/216961790-857d0062-7943-49ef-8927-e602dfbab714.svg)
2023-02-06 21:57:59 +00:00
Carter Anderson
dcc03724a5 Base Sets (#7466)
# Objective

NOTE: This depends on #7267 and should not be merged until #7267 is merged. If you are reviewing this before that is merged, I highly recommend viewing the Base Sets commit instead of trying to find my changes amongst those from #7267.

"Default sets" as described by the [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) have some [unfortunate consequences](https://github.com/bevyengine/bevy/discussions/7365).

## Solution

This adds "base sets" as a variant of `SystemSet`:

A set is a "base set" if `SystemSet::is_base` returns `true`. Typically this will be opted-in to using the `SystemSet` derive:

```rust
#[derive(SystemSet, Clone, Hash, Debug, PartialEq, Eq)]
#[system_set(base)]
enum MyBaseSet {
  A,
  B,
}
``` 

**Base sets are exclusive**: a system can belong to at most one "base set". Adding a system to more than one will result in an error. When possible we fail immediately during system-config-time with a nice file + line number. For the more nested graph-ey cases, this will fail at the final schedule build. 

**Base sets cannot belong to other sets**: this is where the word "base" comes from

Systems and Sets can only be added to base sets using `in_base_set`. Calling `in_set` with a base set will fail. As will calling `in_base_set` with a normal set.

```rust
app.add_system(foo.in_base_set(MyBaseSet::A))
       // X must be a normal set ... base sets cannot be added to base sets
       .configure_set(X.in_base_set(MyBaseSet::A))
```

Base sets can still be configured like normal sets:

```rust
app.add_system(MyBaseSet::B.after(MyBaseSet::Ap))
``` 

The primary use case for base sets is enabling a "default base set":

```rust
schedule.set_default_base_set(CoreSet::Update)
  // this will belong to CoreSet::Update by default
  .add_system(foo)
  // this will override the default base set with PostUpdate
  .add_system(bar.in_base_set(CoreSet::PostUpdate))
```

This allows us to build apis that work by default in the standard Bevy style. This is a rough analog to the "default stage" model, but it use the new "stageless sets" model instead, with all of the ordering flexibility (including exclusive systems) that it provides.

---

## Changelog

- Added "base sets" and ported CoreSet to use them.

## Migration Guide

TODO
2023-02-06 03:10:08 +00:00
Alice Cecile
206c7ce219 Migrate engine to Schedule v3 (#7267)
Huge thanks to @maniwani, @devil-ira, @hymm, @cart, @superdump and @jakobhellermann for the help with this PR.

# Objective

- Followup #6587.
- Minimal integration for the Stageless Scheduling RFC: https://github.com/bevyengine/rfcs/pull/45

## Solution

- [x]  Remove old scheduling module
- [x] Migrate new methods to no longer use extension methods
- [x] Fix compiler errors
- [x] Fix benchmarks
- [x] Fix examples
- [x] Fix docs
- [x] Fix tests

## Changelog

### Added

- a large number of methods on `App` to work with schedules ergonomically
- the `CoreSchedule` enum
- `App::add_extract_system` via the `RenderingAppExtension` trait extension method
- the private `prepare_view_uniforms` system now has a public system set for scheduling purposes, called `ViewSet::PrepareUniforms`

### Removed

- stages, and all code that mentions stages
- states have been dramatically simplified, and no longer use a stack
- `RunCriteriaLabel`
- `AsSystemLabel` trait
- `on_hierarchy_reports_enabled` run criteria (now just uses an ad hoc resource checking run condition)
- systems in `RenderSet/Stage::Extract` no longer warn when they do not read data from the main world
- `RunCriteriaLabel`
- `transform_propagate_system_set`: this was a nonstandard pattern that didn't actually provide enough control. The systems are already `pub`: the docs have been updated to ensure that the third-party usage is clear.

### Changed

- `System::default_labels` is now `System::default_system_sets`.
- `App::add_default_labels` is now `App::add_default_sets`
- `CoreStage` and `StartupStage` enums are now `CoreSet` and `StartupSet`
- `App::add_system_set` was renamed to `App::add_systems`
- The `StartupSchedule` label is now defined as part of the `CoreSchedules` enum
-  `.label(SystemLabel)` is now referred to as `.in_set(SystemSet)`
- `SystemLabel` trait was replaced by `SystemSet`
- `SystemTypeIdLabel<T>` was replaced by `SystemSetType<T>`
- The `ReportHierarchyIssue` resource now has a public constructor (`new`), and implements `PartialEq`
- Fixed time steps now use a schedule (`CoreSchedule::FixedTimeStep`) rather than a run criteria.
- Adding rendering extraction systems now panics rather than silently failing if no subapp with the `RenderApp` label is found.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied. 
- `SceneSpawnerSystem` now runs under `CoreSet::Update`, rather than `CoreStage::PreUpdate.at_end()`.
- `bevy_pbr::add_clusters` is no longer an exclusive system
- the top level `bevy_ecs::schedule` module was replaced with `bevy_ecs::scheduling`
- `tick_global_task_pools_on_main_thread` is no longer run as an exclusive system. Instead, it has been replaced by `tick_global_task_pools`, which uses a `NonSend` resource to force running on the main thread.

## Migration Guide

- Calls to `.label(MyLabel)` should be replaced with `.in_set(MySet)`
- Stages have been removed. Replace these with system sets, and then add command flushes using the `apply_system_buffers` exclusive system where needed.
- The `CoreStage`, `StartupStage, `RenderStage` and `AssetStage`  enums have been replaced with `CoreSet`, `StartupSet, `RenderSet` and `AssetSet`. The same scheduling guarantees have been preserved.
  - Systems are no longer added to `CoreSet::Update` by default. Add systems manually if this behavior is needed, although you should consider adding your game logic systems to `CoreSchedule::FixedTimestep` instead for more reliable framerate-independent behavior.
  - Similarly, startup systems are no longer part of `StartupSet::Startup` by default. In most cases, this won't matter to you.
  - For example, `add_system_to_stage(CoreStage::PostUpdate, my_system)` should be replaced with 
  - `add_system(my_system.in_set(CoreSet::PostUpdate)`
- When testing systems or otherwise running them in a headless fashion, simply construct and run a schedule using `Schedule::new()` and `World::run_schedule` rather than constructing stages
- Run criteria have been renamed to run conditions. These can now be combined with each other and with states.
- Looping run criteria and state stacks have been removed. Use an exclusive system that runs a schedule if you need this level of control over system control flow.
- For app-level control flow over which schedules get run when (such as for rollback networking), create your own schedule and insert it under the `CoreSchedule::Outer` label.
- Fixed timesteps are now evaluated in a schedule, rather than controlled via run criteria. The `run_fixed_timestep` system runs this schedule between `CoreSet::First` and `CoreSet::PreUpdate` by default.
- Command flush points introduced by `AssetStage` have been removed. If you were relying on these, add them back manually.
- Adding extract systems is now typically done directly on the main app. Make sure the `RenderingAppExtension` trait is in scope, then call `app.add_extract_system(my_system)`.
- the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied. You may need to order your movement systems to occur before this system in order to avoid system order ambiguities in culling behavior.
- the `RenderLabel` `AppLabel` was renamed to `RenderApp` for clarity
- `App::add_state` now takes 0 arguments: the starting state is set based on the `Default` impl.
- Instead of creating `SystemSet` containers for systems that run in stages, simply use `.on_enter::<State::Variant>()` or its `on_exit` or `on_update` siblings.
- `SystemLabel` derives should be replaced with `SystemSet`. You will also need to add the `Debug`, `PartialEq`, `Eq`, and `Hash` traits to satisfy the new trait bounds.
- `with_run_criteria` has been renamed to `run_if`. Run criteria have been renamed to run conditions for clarity, and should now simply return a bool.
- States have been dramatically simplified: there is no longer a "state stack". To queue a transition to the next state, call `NextState::set`

## TODO

- [x] remove dead methods on App and World
- [x] add `App::add_system_to_schedule` and `App::add_systems_to_schedule`
- [x] avoid adding the default system set at inappropriate times
- [x] remove any accidental cycles in the default plugins schedule
- [x] migrate benchmarks
- [x] expose explicit labels for the built-in command flush points
- [x] migrate engine code
- [x] remove all mentions of stages from the docs
- [x] verify docs for States
- [x] fix uses of exclusive systems that use .end / .at_start / .before_commands
- [x] migrate RenderStage and AssetStage
- [x] migrate examples
- [x] ensure that transform propagation is exported in a sufficiently public way (the systems are already pub)
- [x] ensure that on_enter schedules are run at least once before the main app
- [x] re-enable opt-in to execution order ambiguities
- [x] revert change to `update_bounds` to ensure it runs in `PostUpdate`
- [x] test all examples
  - [x] unbreak directional lights
  - [x] unbreak shadows (see 3d_scene, 3d_shape, lighting, transparaency_3d examples)
  - [x] game menu example shows loading screen and menu simultaneously
  - [x] display settings menu is a blank screen
  - [x] `without_winit` example panics
- [x] ensure all tests pass
  - [x] SubApp doc test fails
  - [x] runs_spawn_local tasks fails
  - [x] [Fix panic_when_hierachy_cycle test hanging](https://github.com/alice-i-cecile/bevy/pull/120)

## Points of Difficulty and Controversy

**Reviewers, please give feedback on these and look closely**

1.  Default sets, from the RFC, have been removed. These added a tremendous amount of implicit complexity and result in hard to debug scheduling errors. They're going to be tackled in the form of "base sets" by @cart in a followup.
2. The outer schedule controls which schedule is run when `App::update` is called.
3. I implemented `Label for `Box<dyn Label>` for our label types. This enables us to store schedule labels in concrete form, and then later run them. I ran into the same set of problems when working with one-shot systems. We've previously investigated this pattern in depth, and it does not appear to lead to extra indirection with nested boxes.
4. `SubApp::update` simply runs the default schedule once. This sucks, but this whole API is incomplete and this was the minimal changeset.
5. `time_system` and `tick_global_task_pools_on_main_thread` no longer use exclusive systems to attempt to force scheduling order
6. Implemetnation strategy for fixed timesteps
7. `AssetStage` was migrated to `AssetSet` without reintroducing command flush points. These did not appear to be used, and it's nice to remove these bottlenecks.
8. Migration of `bevy_render/lib.rs` and pipelined rendering. The logic here is unusually tricky, as we have complex scheduling requirements.

## Future Work (ideally before 0.10)

- Rename schedule_v3 module to schedule or scheduling
- Add a derive macro to states, and likely a `EnumIter` trait of some form
- Figure out what exactly to do with the "systems added should basically work by default" problem
- Improve ergonomics for working with fixed timesteps and states
- Polish FixedTime API to match Time
- Rebase and merge #7415
- Resolve all internal ambiguities (blocked on better tools, especially #7442)
- Add "base sets" to replace the removed default sets.
2023-02-06 02:04:50 +00:00
Alice Cecile
5d514fb24f Reduce internal system order ambiguities, and add an example explaining them (#7383)
# Objective

- Bevy should not have any "internal" execution order ambiguities. These clutter the output of user-facing error reporting, and can result in nasty, nondetermistic, very difficult to solve bugs.
- Verifying this currently involves repeated non-trivial manual work. 

## Solution

- [x] add an example to quickly check this
- ~~[ ] ensure that this example panics if there are any unresolved ambiguities~~
- ~~[ ] run the example in CI 😈~~

There's one tricky ambiguity left, between UI and animation. I don't have the tools to fix this without system set configuration, so the remaining work is going to be left to #7267 or another PR after that.

```
2023-01-27T18:38:42.989405Z  INFO bevy_ecs::schedule::ambiguity_detection: Execution order ambiguities detected, you might want to add an explicit dependency relation between some of these systems:
 * Parallel systems:
 -- "bevy_animation::animation_player" and "bevy_ui::flex::flex_node_system"
    conflicts: ["bevy_transform::components::transform::Transform"]
  ```

## Changelog

Resolved internal execution order ambiguities for:
1. Transform propagation (ignored, we need smarter filter checking).
2. Gamepad processing (fixed).
3. bevy_winit's window handling (fixed).
4. Cascaded shadow maps and perspectives (fixed).

Also fixed a desynchronized state bug that could occur when the `Window` component is removed and then added to the same entity in a single frame.
2023-01-31 01:47:00 +00:00
Marco Buono
1a96d820fd Add Distance and Atmospheric Fog support (#6412)
<img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873533-44c029af-13b7-4740-8ea3-af96bd5867c9.png">
<img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873549-36be7a23-b341-42a2-8a9f-ceea8ac7a2b8.png">


# Objective

- Add support for the “classic” distance fog effect, as well as a more advanced atmospheric fog effect.

## Solution

This PR:

- Introduces a new `FogSettings` component that controls distance fog per-camera. 
- Adds support for three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog;
- Adds support for directional light influence over fog color;
- Extracts fog via `ExtractComponent`, then uses a prepare system that sets up a new dynamic uniform struct (`Fog`), similar to other mesh view types;
- Renders fog in PBR material shader, as a final adjustment to the `output_color`, after PBR is computed (but before tone mapping);
- Adds a new `StandardMaterial` flag to enable fog; (`fog_enabled`)
- Adds convenience methods for easier artistic control when creating non-linear fog types;
- Adds documentation around fog.

---

## Changelog

### Added

- Added support for distance-based fog effects for PBR materials, controllable per-camera via the new `FogSettings` component;
- Added `FogFalloff` enum for selecting between three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog;
2023-01-29 15:28:56 +00:00
Daniel Chia
c3a46822e1 Cascaded shadow maps. (#7064)
Co-authored-by: Robert Swain <robert.swain@gmail.com>

# Objective

Implements cascaded shadow maps for directional lights, which produces better quality shadows without needing excessively large shadow maps.

Fixes #3629

Before
![image](https://user-images.githubusercontent.com/1222141/210061203-bbd965a4-8d11-4cec-9a88-67fc59d0819f.png)

After
![image](https://user-images.githubusercontent.com/1222141/210061334-2ff15334-e6d7-4a31-9314-f34a7805cac6.png)


## Solution

Rather than rendering a single shadow map for directional light, the view frustum is divided into a series of cascades, each of which gets its own shadow map. The correct cascade is then sampled for shadow determination.

---

## Changelog

Directional lights now use cascaded shadow maps for improved shadow quality.


## Migration Guide

You no longer have to manually specify a `shadow_projection` for a directional light, and these settings should be removed. If customization of how cascaded shadow maps work is desired, modify the `CascadeShadowConfig` component instead.
2023-01-25 12:35:39 +00:00
IceSentry
b3224e135b Add depth and normal prepass (#6284)
# Objective

- Add a configurable prepass
- A depth prepass is useful for various shader effects and to reduce overdraw. It can be expansive depending on the scene so it's important to be able to disable it if you don't need any effects that uses it or don't suffer from excessive overdraw.
- The goal is to eventually use it for things like TAA, Ambient Occlusion, SSR and various other techniques that can benefit from having a prepass.

## Solution

The prepass node is inserted before the main pass. It runs for each `Camera3d` with a prepass component (`DepthPrepass`, `NormalPrepass`). The presence of one of those components is used to determine which textures are generated in the prepass. When any prepass is enabled, the depth buffer generated will be used by the main pass to reduce overdraw.

The prepass runs for each `Material` created with the `MaterialPlugin::prepass_enabled` option set to `true`. You can overload the shader used by the prepass by using `Material::prepass_vertex_shader()` and/or `Material::prepass_fragment_shader()`. It will also use the `Material::specialize()` for more advanced use cases. It is enabled by default on all materials.

The prepass works on opaque materials and materials using an alpha mask. Transparent materials are ignored.

The `StandardMaterial` overloads the prepass fragment shader to support alpha mask and normal maps.

---

## Changelog

- Add a new `PrepassNode` that runs before the main pass
- Add a `PrepassPlugin` to extract/prepare/queue the necessary data
- Add a `DepthPrepass` and `NormalPrepass` component to control which textures will be created by the prepass and available in later passes.
- Add a new `prepass_enabled` flag to the `MaterialPlugin` that will control if a material uses the prepass or not.
- Add a new `prepass_enabled` flag to the `PbrPlugin` to control if the StandardMaterial uses the prepass. Currently defaults to false.
- Add `Material::prepass_vertex_shader()` and `Material::prepass_fragment_shader()` to control the prepass from the `Material`

## Notes

In bevy's sample 3d scene, the performance is actually worse when enabling the prepass, but on more complex scenes the performance is generally better. I would like more testing on this, but @DGriffin91 has reported a very noticeable improvements in some scenes.

The prepass is also used by @JMS55 for TAA and GTAO

discord thread: <https://discord.com/channels/691052431525675048/1011624228627419187>

This PR was built on top of the work of multiple people

Co-Authored-By: @superdump 
Co-Authored-By: @robtfm 
Co-Authored-By: @JMS55 

Co-authored-by: Charles <IceSentry@users.noreply.github.com>
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2023-01-19 22:11:13 +00:00
Robert Swain
16748b8387 bevy_render: Run calculate_bounds in the end-of-update exclusive systems (#7127)
# Objective

- Avoid slower than necessary first frame after spawning many entities due to them not having `Aabb`s and so being marked visible
  - Avoids unnecessarily large system and VRAM allocations as a consequence

## Solution

- I noticed when debugging the `many_cubes` stress test in Xcode that the `MeshUniform` binding was much larger than it needed to be. I realised that this was because initially, all mesh entities are marked as being visible because they don't have `Aabb`s because `calculate_bounds` is being run in `PostUpdate` and there are no system commands applications before executing the visibility check systems that need the `Aabb`s. The solution then is to run the `calculate_bounds` system just before the previous system commands are applied which is at the end of the `Update` stage.
2023-01-09 13:41:59 +00:00
Rob Parrett
3dd8b42f72 Fix various typos (#7096)
I stumbled across a typo in some docs. Fixed some more while I was in there.
2023-01-06 00:43:30 +00:00
Torstein Grindvik
daa57fe489 Add try_* to add_slot_edge, add_node_edge (#6720)
# Objective

`add_node_edge` and `add_slot_edge` are fallible methods, but are always used with `.unwrap()`.
`input_node` is often unwrapped as well.
This points to having an infallible behaviour as default, with an alternative fallible variant if needed.

Improves readability and ergonomics.

## Solution

- Change `add_node_edge` and `add_slot_edge` to panic on error.
- Change `input_node` to panic on `None`.
- Add `try_add_node_edge` and `try_add_slot_edge` in case fallible methods are needed.
- Add `get_input_node` to still be able to get an `Option`.
---

## Changelog

### Added

- `try_add_node_edge`
- `try_add_slot_edge`
- `get_input_node`

### Changed

- `add_node_edge` is now infallible (panics on error)
- `add_slot_edge` is now infallible (panics on error)
- `input_node` now panics on `None`

## Migration Guide

Remove `.unwrap()` from `add_node_edge` and `add_slot_edge`.
For cases where the error was handled, use `try_add_node_edge` and `try_add_slot_edge` instead.

Remove `.unwrap()` from `input_node`.
For cases where the option was handled, use `get_input_node` instead.


Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
2022-11-21 21:58:39 +00:00
Jakob Hellermann
4ad621fe0f Reflect for Tonemapping and ClusterConfig (#6488)
# Objective

- it would be useful to inspect these structs using reflection

## Solution

- derive and register reflect
- Note that `#[reflect(Component)]` requires `Default` (or `FromWorld`) until #6060, so I implemented `Default` for `Tonemapping` with `is_enabled: false`
2022-11-07 19:44:17 +00:00
JMS55
4c4f47697c Bloom (#6397)
# Objective

- Adds a bloom pass for HDR-enabled Camera3ds.
- Supersedes (and all credit due to!) https://github.com/bevyengine/bevy/pull/3430 and https://github.com/bevyengine/bevy/pull/2876

![image](https://user-images.githubusercontent.com/47158642/198698783-228edc00-20b5-4218-a613-331ccd474f38.png)

## Solution

- A threshold is applied to isolate emissive samples, and then a series of downscale and upscaling passes are applied and composited together.
- Bloom is applied to 2d or 3d Cameras with hdr: true and a BloomSettings component.

---

## Changelog

- Added a `core_pipeline::bloom::BloomSettings` component.
- Added `BloomNode` that runs between the main pass and tonemapping.
- Added a `BloomPlugin` that is loaded as part of CorePipelinePlugin.
- Added a bloom example project.

Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
Co-authored-by: DGriffin91 <github@dgdigital.net>
2022-11-04 01:34:12 +00:00
Alice Cecile
334e09892b Revert "Show prelude re-exports in docs (#6448)" (#6449)
This reverts commit 53d387f340.

# Objective

Reverts #6448. This didn't have the intended effect: we're now getting bevy::prelude shown in the docs again.

Co-authored-by: Alejandro Pascual <alejandro.pascual.pozo@gmail.com>
2022-11-02 20:40:45 +00:00
Alejandro Pascual
53d387f340 Show prelude re-exports in docs (#6448)
# Objective

- Right now re-exports are completely hidden in prelude docs.
- Fixes #6433

## Solution

- We could show the re-exports without inlining their documentation.
2022-11-02 19:35:06 +00:00
Jakob Hellermann
f867319336 add ReflectAsset and ReflectHandle (#5923)
# Objective
![image](https://user-images.githubusercontent.com/22177966/189350194-639a0211-e984-4f73-ae62-0ede44891eb9.png)

^ enable this

Concretely, I need to
- list all handle ids for an asset type
- fetch the asset as `dyn Reflect`, given a `HandleUntyped`
- when encountering a `Handle<T>`, find out what asset type that handle refers to (`T`'s type id) and turn the handle into a `HandleUntyped`

## Solution

- add `ReflectAsset` type containing function pointers for working with assets
```rust
pub struct ReflectAsset {
    type_uuid: Uuid,
    assets_resource_type_id: TypeId, // TypeId of the `Assets<T>` resource

    get: fn(&World, HandleUntyped) -> Option<&dyn Reflect>,
    get_mut: fn(&mut World, HandleUntyped) -> Option<&mut dyn Reflect>,
    get_unchecked_mut: unsafe fn(&World, HandleUntyped) -> Option<&mut dyn Reflect>,
    add: fn(&mut World, &dyn Reflect) -> HandleUntyped,
    set: fn(&mut World, HandleUntyped, &dyn Reflect) -> HandleUntyped,
    len: fn(&World) -> usize,
    ids: for<'w> fn(&'w World) -> Box<dyn Iterator<Item = HandleId> + 'w>,
    remove: fn(&mut World, HandleUntyped) -> Option<Box<dyn Reflect>>,
}
```
- add `ReflectHandle` type relating the handle back to the asset type and providing a way to create a `HandleUntyped`
```rust
pub struct ReflectHandle {
    type_uuid: Uuid,
    asset_type_id: TypeId,
    downcast_handle_untyped: fn(&dyn Any) -> Option<HandleUntyped>,
}
```
- add the corresponding `FromType` impls
- add a function `app.register_asset_reflect` which is supposed to be called after `.add_asset` and registers `ReflectAsset` and `ReflectHandle` in the type registry
---

## Changelog

- add `ReflectAsset` and `ReflectHandle` types, which allow code to use reflection to manipulate arbitrary assets without knowing their types at compile time
2022-10-28 20:42:33 +00:00
JoJoJet
456971381c Resolve most remaining execution-order ambiguities (#6341)
# Objective

Bevy's internal plugins have lots of execution-order ambiguities, which makes the ambiguity detection tool very noisy for our users.

## Solution

Silence every last ambiguity that can currently be resolved.
Each time an ambiguity is silenced, it is accompanied by a comment describing why it is correct. This description should be based on the public API of the respective systems. Thus, I have added documentation to some systems describing how they use some resources.

# Future work

Some ambiguities remain, due to issues out of scope for this PR. 

* The ambiguity checker does not respect `Without<>` filters, leading to false positives.
* Ambiguities between `bevy_ui` and `bevy_animation` cannot be resolved, since neither crate knows that the other exists. We will need a general solution to this problem.
2022-10-27 12:56:03 +00:00
Carter Anderson
dc3f801239 Exclusive Systems Now Implement System. Flexible Exclusive System Params (#6083)
# Objective

The [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) involves allowing exclusive systems to be referenced and ordered relative to parallel systems. We've agreed that unifying systems under `System` is the right move.

This is an alternative to #4166 (see rationale in the comments I left there). Note that this builds on the learnings established there (and borrows some patterns).

## Solution

This unifies parallel and exclusive systems under the shared `System` trait, removing the old `ExclusiveSystem` trait / impls. This is accomplished by adding a new `ExclusiveFunctionSystem` impl similar to `FunctionSystem`. It is backed by `ExclusiveSystemParam`, which is similar to `SystemParam`. There is a new flattened out SystemContainer api (which cuts out a lot of trait and type complexity). 

This means you can remove all cases of `exclusive_system()`:

```rust
// before
commands.add_system(some_system.exclusive_system());
// after
commands.add_system(some_system);
```

I've also implemented `ExclusiveSystemParam` for `&mut QueryState` and `&mut SystemState`, which makes this possible in exclusive systems:

```rust
fn some_exclusive_system(
    world: &mut World,
    transforms: &mut QueryState<&Transform>,
    state: &mut SystemState<(Res<Time>, Query<&Player>)>,
) {
    for transform in transforms.iter(world) {
        println!("{transform:?}");
    }
    let (time, players) = state.get(world);
    for player in players.iter() {
        println!("{player:?}");
    }
}
```

Note that "exclusive function systems" assume `&mut World` is present (and the first param). I think this is a fair assumption, given that the presence of `&mut World` is what defines the need for an exclusive system.

I added some targeted SystemParam `static` constraints, which removed the need for this:
``` rust
fn some_exclusive_system(state: &mut SystemState<(Res<'static, Time>, Query<&'static Player>)>) {}
```

## Related

- #2923
- #3001
- #3946

## Changelog

- `ExclusiveSystem` trait (and implementations) has been removed in favor of sharing the `System` trait.
- `ExclusiveFunctionSystem` and `ExclusiveSystemParam` were added, enabling flexible exclusive function systems
- `&mut SystemState` and `&mut QueryState` now implement `ExclusiveSystemParam`
- Exclusive and parallel System configuration is now done via a unified `SystemDescriptor`, `IntoSystemDescriptor`, and `SystemContainer` api.

## Migration Guide

Calling `.exclusive_system()` is no longer required (or supported) for converting exclusive system functions to exclusive systems:

```rust
// Old (0.8)
app.add_system(some_exclusive_system.exclusive_system());
// New (0.9)
app.add_system(some_exclusive_system);
```

Converting "normal" parallel systems to exclusive systems is done by calling the exclusive ordering apis:

```rust
// Old (0.8)
app.add_system(some_system.exclusive_system().at_end());
// New (0.9)
app.add_system(some_system.at_end());
```

Query state in exclusive systems can now be cached via ExclusiveSystemParams, which should be preferred for clarity and performance reasons:
```rust
// Old (0.8)
fn some_system(world: &mut World) {
  let mut transforms = world.query::<&Transform>();
  for transform in transforms.iter(world) {
  }
}
// New (0.9)
fn some_system(world: &mut World, transforms: &mut QueryState<&Transform>) {
  for transform in transforms.iter(world) {
  }
}
```
2022-09-26 23:57:07 +00:00
Carter Anderson
40d4992401 Visibilty Inheritance, universal ComputedVisibility and RenderLayers support (#5310)
# Objective

Fixes #4907. Fixes #838. Fixes #5089.
Supersedes #5146. Supersedes #2087. Supersedes #865. Supersedes #5114

Visibility is currently entirely local. Set a parent entity to be invisible, and the children are still visible. This makes it hard for users to hide entire hierarchies of entities.

Additionally, the semantics of `Visibility` vs `ComputedVisibility` are inconsistent across entity types. 3D meshes use `ComputedVisibility` as the "definitive" visibility component, with `Visibility` being just one data source. Sprites just use `Visibility`, which means they can't feed off of `ComputedVisibility` data, such as culling information, RenderLayers, and (added in this pr) visibility inheritance information.

## Solution

Splits `ComputedVisibilty::is_visible` into `ComputedVisibilty::is_visible_in_view` and `ComputedVisibilty::is_visible_in_hierarchy`. For each visible entity, `is_visible_in_hierarchy` is computed by propagating visibility down the hierarchy. The `ComputedVisibility::is_visible()` function combines these two booleans for the canonical "is this entity visible" function.

Additionally, all entities that have `Visibility` now also have `ComputedVisibility`.  Sprites, Lights, and UI entities now use `ComputedVisibility` when appropriate.

This means that in addition to visibility inheritance, everything using Visibility now also supports RenderLayers. Notably, Sprites (and other 2d objects) now support `RenderLayers` and work properly across multiple views.

Also note that this does increase the amount of work done per sprite. Bevymark with 100,000 sprites on `main` runs in `0.017612` seconds and this runs in `0.01902`. That is certainly a gap, but I believe the api consistency and extra functionality this buys us is worth it. See [this thread](https://github.com/bevyengine/bevy/pull/5146#issuecomment-1182783452) for more info. Note that #5146 in combination with #5114 _are_ a viable alternative to this PR and _would_ perform better, but that comes at the cost of api inconsistencies and doing visibility calculations in the "wrong" place. The current visibility system does have potential for performance improvements. I would prefer to evolve that one system as a whole rather than doing custom hacks / different behaviors for each feature slice.

Here is a "split screen" example where the left camera uses RenderLayers to filter out the blue sprite.

![image](https://user-images.githubusercontent.com/2694663/178814868-2e9a2173-bf8c-4c79-8815-633899d492c3.png)


Note that this builds directly on #5146 and that @james7132 deserves the credit for the baseline visibility inheritance work. This pr moves the inherited visibility field into `ComputedVisibility`, then does the additional work of porting everything to `ComputedVisibility`. See my [comments here](https://github.com/bevyengine/bevy/pull/5146#issuecomment-1182783452) for rationale. 

## Follow up work

* Now that lights use ComputedVisibility, VisibleEntities now includes "visible lights" in the entity list. Functionally not a problem as we use queries to filter the list down in the desired context. But we should consider splitting this out into a separate`VisibleLights` collection for both clarity and performance reasons. And _maybe_ even consider scoping `VisibleEntities` down to `VisibleMeshes`?.
* Investigate alternative sprite rendering impls (in combination with visibility system tweaks) that avoid re-generating a per-view fixedbitset of visible entities every frame, then checking each ExtractedEntity. This is where most of the performance overhead lives. Ex: we could generate ExtractedEntities per-view using the VisibleEntities list, avoiding the need for the bitset.
* Should ComputedVisibility use bitflags under the hood? This would cut down on the size of the component, potentially speed up the `is_visible()` function, and allow us to cheaply expand ComputedVisibility with more data (ex: split out local visibility and parent visibility, add more culling classes, etc).
---

## Changelog

* ComputedVisibility now takes hierarchy visibility into account.
* 2D, UI and Light entities now use the ComputedVisibility component.

## Migration Guide

If you were previously reading `Visibility::is_visible` as the "actual visibility" for sprites or lights, use `ComputedVisibilty::is_visible()` instead:

```rust
// before (0.7)
fn system(query: Query<&Visibility>) {
  for visibility in query.iter() {
    if visibility.is_visible {
       log!("found visible entity");
    }
  }
}

// after (0.8)
fn system(query: Query<&ComputedVisibility>) {
  for visibility in query.iter() {
    if visibility.is_visible() {
       log!("found visible entity");
    }
  }
}
``` 


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-07-15 23:24:42 +00:00
robtfm
132950cd55 Spotlights (#4715)
# Objective

add spotlight support

## Solution / Changelog

- add spotlight angles (inner, outer) to ``PointLight`` struct. emitted light is linearly attenuated from 100% to 0% as angle tends from inner to outer. Direction is taken from the existing transform rotation.
- add spotlight direction (vec3) and angles (f32,f32) to ``GpuPointLight`` struct (60 bytes -> 80 bytes) in ``pbr/render/lights.rs`` and ``mesh_view_bind_group.wgsl``
- reduce no-buffer-support max point light count to 204 due to above
- use spotlight data to attenuate light in ``pbr.wgsl``
- do additional cluster culling on spotlights to minimise cost in ``assign_lights_to_clusters``
- changed one of the lights in the lighting demo to a spotlight
- also added a ``spotlight`` demo - probably not justified but so reviewers can see it more easily

## notes

increasing the size of the GpuPointLight struct on my machine reduces the FPS of ``many_lights -- sphere`` from ~150fps to 140fps. 

i thought this was a reasonable tradeoff, and felt better than handling spotlights separately which is possible but would mean introducing a new bind group, refactoring light-assignment code and adding new spotlight-specific code in pbr.wgsl. the FPS impact for smaller numbers of lights should be very small.

the cluster culling strategy reintroduces the cluster aabb code which was recently removed... sorry. the aabb is used to get a cluster bounding sphere, which can then be tested fairly efficiently using the strategy described at the end of https://bartwronski.com/2017/04/13/cull-that-cone/. this works well with roughly cubic clusters (where the cluster z size is close to the same as x/y size), less well for other cases like single Z slice / tiled forward rendering. In the worst case we will end up just keeping the culling of the equivalent point light.

Co-authored-by: François <mockersf@gmail.com>
2022-07-08 19:57:43 +00:00
Hennadii Chernyshchyk
534cad611d Add reflection for resources (#5175)
# Objective

We don't have reflection for resources.

## Solution

Introduce reflection for resources.

Continues #3580 (by @Davier), related to #3576.

---

## Changelog

### Added

* Reflection on a resource type (by adding `ReflectResource`):

```rust
#[derive(Reflect)]
#[reflect(Resource)]
struct MyResourse;
```

### Changed

* Rename `ReflectComponent::add_component` into `ReflectComponent::insert_component` for consistency.

## Migration Guide

* Rename `ReflectComponent::add_component` into `ReflectComponent::insert_component`.
2022-07-04 13:04:20 +00:00
Robert Swain
114d169dce Callable PBR functions (#4939)
# Objective

- Builds on top of #4938 
- Make clustered-forward PBR lighting/shadows functionality callable
- See #3969 for details

## Solution

- Add `PbrInput` struct type containing a `StandardMaterial`, occlusion, world_position, world_normal, and frag_coord
- Split functionality to calculate the unit view vector, and normal-mapped normal into `bevy_pbr::pbr_functions`
- Split high-level shading flow into `pbr(in: PbrInput, N: vec3<f32>, V: vec3<f32>, is_orthographic: bool)` function in `bevy_pbr::pbr_functions`
- Rework `pbr.wgsl` fragment stage entry point to make use of the new functions
- This has been benchmarked on an M1 Max using `many_cubes -- sphere`. `main` had a median frame time of 15.88ms, this PR 15.99ms, which is a 0.69% frame time increase, which is within noise in my opinion.

---

## Changelog

- Added: PBR shading code is now callable. Import `bevy_pbr::pbr_functions` and its dependencies, create a `PbrInput`, calculate the unit view and normal-mapped normal vectors and whether the projection is orthographic, and call `pbr()`!
2022-06-21 20:50:06 +00:00
Robert Swain
c6222f1acc Separate out PBR lighting, shadows, clustered forward, and utils from pbr.wgsl (#4938)
# Objective

- Builds on top of #4901 
- Separate out PBR lighting, shadows, clustered forward, and utils from `pbr.wgsl` as part of making the PBR code more reusable and extensible.
- See #3969 for details.

## Solution

- Add `bevy_pbr::utils`, `bevy_pbr::clustered_forward`, `bevy_pbr::lighting`, `bevy_pbr::shadows` shader imports exposing many shader functions for external use
- Split `PI`, `saturate()`, `hsv2rgb()`, and `random1D()` into `bevy_pbr::utils`
- Split clustered-forward-specific functions into `bevy_pbr::clustered_forward`, including moving the debug visualization code into a `cluster_debug_visualization()` function in that import
- Split PBR lighting functions into `bevy_pbr::lighting`
- Split shadow functions into `bevy_pbr::shadows`

---

## Changelog

- Added: `bevy_pbr::utils`, `bevy_pbr::clustered_forward`, `bevy_pbr::lighting`, `bevy_pbr::shadows` shader imports exposing many shader functions for external use
  - Split `PI`, `saturate()`, `hsv2rgb()`, and `random1D()` into `bevy_pbr::utils`
  - Split clustered-forward-specific functions into `bevy_pbr::clustered_forward`, including moving the debug visualization code into a `cluster_debug_visualization()` function in that import
  - Split PBR lighting functions into `bevy_pbr::lighting`
  - Split shadow functions into `bevy_pbr::shadows`
2022-06-14 00:58:30 +00:00
Carter Anderson
f487407e07 Camera Driven Rendering (#4745)
This adds "high level camera driven rendering" to Bevy. The goal is to give users more control over what gets rendered (and where) without needing to deal with render logic. This will make scenarios like "render to texture", "multiple windows", "split screen", "2d on 3d", "3d on 2d", "pass layering", and more significantly easier. 

Here is an [example of a 2d render sandwiched between two 3d renders (each from a different perspective)](https://gist.github.com/cart/4fe56874b2e53bc5594a182fc76f4915):
![image](https://user-images.githubusercontent.com/2694663/168411086-af13dec8-0093-4a84-bdd4-d4362d850ffa.png)

Users can now spawn a camera, point it at a RenderTarget (a texture or a window), and it will "just work". 

Rendering to a second window is as simple as spawning a second camera and assigning it to a specific window id:
```rust
// main camera (main window)
commands.spawn_bundle(Camera2dBundle::default());

// second camera (other window)
commands.spawn_bundle(Camera2dBundle {
    camera: Camera {
        target: RenderTarget::Window(window_id),
        ..default()
    },
    ..default()
});
```

Rendering to a texture is as simple as pointing the camera at a texture:

```rust
commands.spawn_bundle(Camera2dBundle {
    camera: Camera {
        target: RenderTarget::Texture(image_handle),
        ..default()
    },
    ..default()
});
```

Cameras now have a "render priority", which controls the order they are drawn in. If you want to use a camera's output texture as a texture in the main pass, just set the priority to a number lower than the main pass camera (which defaults to `0`).

```rust
// main pass camera with a default priority of 0
commands.spawn_bundle(Camera2dBundle::default());

commands.spawn_bundle(Camera2dBundle {
    camera: Camera {
        target: RenderTarget::Texture(image_handle.clone()),
        priority: -1,
        ..default()
    },
    ..default()
});

commands.spawn_bundle(SpriteBundle {
    texture: image_handle,
    ..default()
})
```

Priority can also be used to layer to cameras on top of each other for the same RenderTarget. This is what "2d on top of 3d" looks like in the new system:

```rust
commands.spawn_bundle(Camera3dBundle::default());

commands.spawn_bundle(Camera2dBundle {
    camera: Camera {
        // this will render 2d entities "on top" of the default 3d camera's render
        priority: 1,
        ..default()
    },
    ..default()
});
```

There is no longer the concept of a global "active camera". Resources like `ActiveCamera<Camera2d>` and `ActiveCamera<Camera3d>` have been replaced with the camera-specific `Camera::is_active` field. This does put the onus on users to manage which cameras should be active.

Cameras are now assigned a single render graph as an "entry point", which is configured on each camera entity using the new `CameraRenderGraph` component. The old `PerspectiveCameraBundle` and `OrthographicCameraBundle` (generic on camera marker components like Camera2d and Camera3d) have been replaced by `Camera3dBundle` and `Camera2dBundle`, which set 3d and 2d default values for the `CameraRenderGraph` and projections.

```rust
// old 3d perspective camera
commands.spawn_bundle(PerspectiveCameraBundle::default())

// new 3d perspective camera
commands.spawn_bundle(Camera3dBundle::default())
```

```rust
// old 2d orthographic camera
commands.spawn_bundle(OrthographicCameraBundle::new_2d())

// new 2d orthographic camera
commands.spawn_bundle(Camera2dBundle::default())
```

```rust
// old 3d orthographic camera
commands.spawn_bundle(OrthographicCameraBundle::new_3d())

// new 3d orthographic camera
commands.spawn_bundle(Camera3dBundle {
    projection: OrthographicProjection {
        scale: 3.0,
        scaling_mode: ScalingMode::FixedVertical,
        ..default()
    }.into(),
    ..default()
})
```

Note that `Camera3dBundle` now uses a new `Projection` enum instead of hard coding the projection into the type. There are a number of motivators for this change: the render graph is now a part of the bundle, the way "generic bundles" work in the rust type system prevents nice `..default()` syntax, and changing projections at runtime is much easier with an enum (ex for editor scenarios). I'm open to discussing this choice, but I'm relatively certain we will all come to the same conclusion here. Camera2dBundle and Camera3dBundle are much clearer than being generic on marker components / using non-default constructors.

If you want to run a custom render graph on a camera, just set the `CameraRenderGraph` component:

```rust
commands.spawn_bundle(Camera3dBundle {
    camera_render_graph: CameraRenderGraph::new(some_render_graph_name),
    ..default()
})
```

Just note that if the graph requires data from specific components to work (such as `Camera3d` config, which is provided in the `Camera3dBundle`), make sure the relevant components have been added.

Speaking of using components to configure graphs / passes, there are a number of new configuration options:

```rust
commands.spawn_bundle(Camera3dBundle {
    camera_3d: Camera3d {
        // overrides the default global clear color 
        clear_color: ClearColorConfig::Custom(Color::RED),
        ..default()
    },
    ..default()
})

commands.spawn_bundle(Camera3dBundle {
    camera_3d: Camera3d {
        // disables clearing
        clear_color: ClearColorConfig::None,
        ..default()
    },
    ..default()
})
```

Expect to see more of the "graph configuration Components on Cameras" pattern in the future.

By popular demand, UI no longer requires a dedicated camera. `UiCameraBundle` has been removed. `Camera2dBundle` and `Camera3dBundle` now both default to rendering UI as part of their own render graphs. To disable UI rendering for a camera, disable it using the CameraUi component:

```rust
commands
    .spawn_bundle(Camera3dBundle::default())
    .insert(CameraUi {
        is_enabled: false,
        ..default()
    })
```

## Other Changes

* The separate clear pass has been removed. We should revisit this for things like sky rendering, but I think this PR should "keep it simple" until we're ready to properly support that (for code complexity and performance reasons). We can come up with the right design for a modular clear pass in a followup pr.
* I reorganized bevy_core_pipeline into Core2dPlugin and Core3dPlugin (and core_2d / core_3d modules). Everything is pretty much the same as before, just logically separate. I've moved relevant types (like Camera2d, Camera3d, Camera3dBundle, Camera2dBundle) into their relevant modules, which is what motivated this reorganization.
* I adapted the `scene_viewer` example (which relied on the ActiveCameras behavior) to the new system. I also refactored bits and pieces to be a bit simpler. 
* All of the examples have been ported to the new camera approach. `render_to_texture` and `multiple_windows` are now _much_ simpler. I removed `two_passes` because it is less relevant with the new approach. If someone wants to add a new "layered custom pass with CameraRenderGraph" example, that might fill a similar niche. But I don't feel much pressure to add that in this pr.
* Cameras now have `target_logical_size` and `target_physical_size` fields, which makes finding the size of a camera's render target _much_ simpler. As a result, the `Assets<Image>` and `Windows` parameters were removed from `Camera::world_to_screen`, making that operation much more ergonomic.
* Render order ambiguities between cameras with the same target and the same priority now produce a warning. This accomplishes two goals:
    1. Now that there is no "global" active camera, by default spawning two cameras will result in two renders (one covering the other). This would be a silent performance killer that would be hard to detect after the fact. By detecting ambiguities, we can provide a helpful warning when this occurs.
    2. Render order ambiguities could result in unexpected / unpredictable render results. Resolving them makes sense.

## Follow Up Work

* Per-Camera viewports, which will make it possible to render to a smaller area inside of a RenderTarget (great for something like splitscreen)
* Camera-specific MSAA config (should use the same "overriding" pattern used for ClearColor)
* Graph Based Camera Ordering: priorities are simple, but they make complicated ordering constraints harder to express. We should consider adopting a "graph based" camera ordering model with "before" and "after" relationships to other cameras (or build it "on top" of the priority system).
* Consider allowing graphs to run subgraphs from any nest level (aka a global namespace for graphs). Right now the 2d and 3d graphs each need their own UI subgraph, which feels "fine" in the short term. But being able to share subgraphs between other subgraphs seems valuable.
* Consider splitting `bevy_core_pipeline` into `bevy_core_2d` and `bevy_core_3d` packages. Theres a shared "clear color" dependency here, which would need a new home.
2022-06-02 00:12:17 +00:00
Robert Swain
cc4062ec43 Split mesh shader files (#4867)
# Objective

- Split PBR and 2D mesh shaders into types and bindings to prepare the shaders to be more reusable.
- See #3969 for details. I'm doing this in multiple steps to make review easier.

---

## Changelog

- Changed: 2D and PBR mesh shaders are now split into types and bindings, the following shader imports are available: `bevy_pbr::mesh_view_types`, `bevy_pbr::mesh_view_bindings`, `bevy_pbr::mesh_types`, `bevy_pbr::mesh_bindings`, `bevy_sprite::mesh2d_view_types`, `bevy_sprite::mesh2d_view_bindings`, `bevy_sprite::mesh2d_types`, `bevy_sprite::mesh2d_bindings`

## Migration Guide

- In shaders for 3D meshes:
  - `#import bevy_pbr::mesh_view_bind_group` -> `#import bevy_pbr::mesh_view_bindings`
  - `#import bevy_pbr::mesh_struct` -> `#import bevy_pbr::mesh_types`
    - NOTE: If you are using the mesh bind group at bind group index 2, you can remove those binding statements in your shader and just use `#import bevy_pbr::mesh_bindings` which itself imports the mesh types needed for the bindings.
- In shaders for 2D meshes:
  - `#import bevy_sprite::mesh2d_view_bind_group` -> `#import bevy_sprite::mesh2d_view_bindings`
  - `#import bevy_sprite::mesh2d_struct` -> `#import bevy_sprite::mesh2d_types`
    - NOTE: If you are using the mesh2d bind group at bind group index 2, you can remove those binding statements in your shader and just use `#import bevy_sprite::mesh2d_bindings` which itself imports the mesh2d types needed for the bindings.
2022-05-31 23:23:25 +00:00
Robert Swain
a0a3d8798b ExtractResourcePlugin (#3745)
# Objective

- Add an `ExtractResourcePlugin` for convenience and consistency

## Solution

- Add an `ExtractResourcePlugin` similar to `ExtractComponentPlugin` but for ECS `Resource`s. The system that is executed simply clones the main world resource into a render world resource, if and only if the main world resource was either added or changed since the last execution of the system.
- Add an `ExtractResource` trait with a `fn extract_resource(res: &Self) -> Self` function. This is used by the `ExtractResourcePlugin` to extract the resource
- Add a derive macro for `ExtractResource` on a `Resource` with the `Clone` trait, that simply returns `res.clone()`
- Use `ExtractResourcePlugin` wherever both possible and appropriate
2022-05-30 18:36:03 +00:00
SarthakSingh31
5155034a58 Converted exclusive systems to parallel systems wherever possible (#2774)
Closes #2767.

Converted:
- `play_queued_audio_system`
- `change_window`
2022-04-25 14:32:56 +00:00
Robert Swain
c5963b4fd5 Use storage buffers for clustered forward point lights (#3989)
# Objective

- Make use of storage buffers, where they are available, for clustered forward bindings to support far more point lights in a scene
- Fixes #3605 
- Based on top of #4079 

This branch on an M1 Max can keep 60fps with about 2150 point lights of radius 1m in the Sponza scene where I've been testing. The bottleneck is mostly assigning lights to clusters which grows faster than linearly (I think 1000 lights was about 1.5ms and 5000 was 7.5ms). I have seen papers and presentations leveraging compute shaders that can get this up to over 1 million. That said, I think any further optimisations should probably be done in a separate PR.

## Solution

- Add `RenderDevice` to the `Material` and `SpecializedMaterial` trait `::key()` functions to allow setting flags on the keys depending on feature/limit availability
- Make `GpuPointLights` and `ViewClusterBuffers` into enums containing `UniformVec` and `StorageBuffer` variants. Implement the necessary API on them to make usage the same for both cases, and the only difference is at initialisation time.
- Appropriate shader defs in the shader code to handle the two cases

## Context on some decisions / open questions

- I'm using `max_storage_buffers_per_shader_stage >= 3` as a check to see if storage buffers are supported. I was thinking about diving into 'binding resource management' but it feels like we don't have enough use cases to understand the problem yet, and it is mostly a separate concern to this PR, so I think it should be handled separately.
- Should `ViewClusterBuffers` and `ViewClusterBindings` be merged, duplicating the count variables into the enum variants?


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-04-07 16:16:35 +00:00
Carter Anderson
207ebde020 Always update clusters and remove per-frame allocations (#4169)
* Refactor assign_lights_to_clusters to always clear + update clusters, even if the screen size isn't available yet / is zero. This fixes #4167. We still avoid the "expensive" per-light work when the screen size isn't available yet. I also consolidated some logic to eliminate some redundancies.
* Removed _a ton_ of (potentially very large) per-frame reallocations
  * Removed `Res<VisiblePointLights>` (a vec) in favor of  `Res<GlobalVisiblePointLights>` (a hashmap). We were allocating a new hashmap every frame, the collecting it into a vec every frame, then in another system _re-generating the hashmap_. It is always used like a hashmap, might as well embrace that. We now reuse the same hashmap every frame and dont use any intermediate collections.
  * We were re-allocating Clusters aabb and light vectors every frame by re-constructing Clusters every frame. We now re-use the existing collections.
  * Reuse per-camera VisiblePointLight vecs when possible instead of allocating them every frame. We now only insert VisiblePointLights if the component doesn't exist yet.
2022-03-24 00:20:27 +00:00
robtfm
244687a0bb Dynamic light clusters (#3968)
# Objective

provide some customisation for default cluster setup
avoid "cluster index lists is full" in all cases (using a strategy outlined by @superdump)

## Solution

Add ClusterConfig enum (which can be inserted into a view at any time) to allow specifying cluster setup with variants:
- None (do not do any light assignment - for views which do not require light info, e.g. minimaps etc)
- Single (one cluster)
- XYZ (explicit cluster counts in each dimension)
- FixedZ (most similar to current - specify Z-slices and total, then x and y counts are dynamically determined to give approximately square clusters based on current aspect ratio)
Defaults to FixedZ { total: 4096, z: 24 } which is similar to the current setup.

Per frame, estimate the number of indices that would be required for the current config and decrease the cluster counts / increase the cluster sizes in the x and y dimensions if the index list would be too small.

notes:

- I didn't put ClusterConfig in the camera bundles to avoid introducing a dependency from bevy_render to bevy_pbr. the ClusterConfig enum comes with a pbr-centric impl block so i didn't want to move that into bevy_render either.
- ~Might want to add None variant to cluster config for views that don't care about lights?~
- Not well tested for orthographic
- ~there's a cluster_muck branch on my repo which includes some diagnostics / a modified lighting example which may be useful for tyre-kicking~ (outdated, i will bring it up to date if required)

anecdotal timings:

FPS on the lighting demo is negligibly better (~5%), maybe due to a small optimisation constraining the light aabb to be in front of the camera
FPS on the lighting demo with 100 extra lights added is ~33% faster, and also renders correctly as the cluster index count is no longer exceeded
2022-03-08 04:56:42 +00:00
Alice Cecile
557ab9897a Make get_resource (and friends) infallible (#4047)
# Objective

- In the large majority of cases, users were calling `.unwrap()` immediately after `.get_resource`.
- Attempting to add more helpful error messages here resulted in endless manual boilerplate (see #3899 and the linked PRs).

## Solution

- Add an infallible variant named `.resource` and so on.
- Use these infallible variants over `.get_resource().unwrap()` across the code base.

## Notes

I did not provide equivalent methods on `WorldCell`, in favor of removing it entirely in #3939.

## Migration Guide

Infallible variants of `.get_resource` have been added that implicitly panic, rather than needing to be unwrapped.

Replace `world.get_resource::<Foo>().unwrap()` with `world.resource::<Foo>()`.

## Impact

- `.unwrap` search results before: 1084
- `.unwrap` search results after: 942
- internal `unwrap_or_else` calls added: 4
- trivial unwrap calls removed from tests and code: 146
- uses of the new `try_get_resource` API: 11
- percentage of the time the unwrapping API was used internally: 93%
2022-02-27 22:37:18 +00:00
Carter Anderson
e369a8ad51 Mesh vertex buffer layouts (#3959)
This PR makes a number of changes to how meshes and vertex attributes are handled, which the goal of enabling easy and flexible custom vertex attributes:
* Reworks the `Mesh` type to use the newly added `VertexAttribute` internally
  * `VertexAttribute` defines the name, a unique `VertexAttributeId`, and a `VertexFormat`
  *  `VertexAttributeId` is used to produce consistent sort orders for vertex buffer generation, replacing the more expensive and often surprising "name based sorting"  
  * Meshes can be used to generate a `MeshVertexBufferLayout`, which defines the layout of the gpu buffer produced by the mesh. `MeshVertexBufferLayouts` can then be used to generate actual `VertexBufferLayouts` according to the requirements of a specific pipeline. This decoupling of "mesh layout" vs "pipeline vertex buffer layout" is what enables custom attributes. We don't need to standardize _mesh layouts_ or contort meshes to meet the needs of a specific pipeline. As long as the mesh has what the pipeline needs, it will work transparently. 
* Mesh-based pipelines now specialize on `&MeshVertexBufferLayout` via the new `SpecializedMeshPipeline` trait (which behaves like `SpecializedPipeline`, but adds `&MeshVertexBufferLayout`). The integrity of the pipeline cache is maintained because the `MeshVertexBufferLayout` is treated as part of the key (which is fully abstracted from implementers of the trait ... no need to add any additional info to the specialization key).    
* Hashing `MeshVertexBufferLayout` is too expensive to do for every entity, every frame. To make this scalable, I added a generalized "pre-hashing" solution to `bevy_utils`: `Hashed<T>` keys and `PreHashMap<K, V>` (which uses `Hashed<T>` internally) . Why didn't I just do the quick and dirty in-place "pre-compute hash and use that u64 as a key in a hashmap" that we've done in the past? Because its wrong! Hashes by themselves aren't enough because two different values can produce the same hash. Re-hashing a hash is even worse! I decided to build a generalized solution because this pattern has come up in the past and we've chosen to do the wrong thing. Now we can do the right thing! This did unfortunately require pulling in `hashbrown` and using that in `bevy_utils`, because avoiding re-hashes requires the `raw_entry_mut` api, which isn't stabilized yet (and may never be ... `entry_ref` has favor now, but also isn't available yet). If std's HashMap ever provides the tools we need, we can move back to that. Note that adding `hashbrown` doesn't increase our dependency count because it was already in our tree. I will probably break these changes out into their own PR.
* Specializing on `MeshVertexBufferLayout` has one non-obvious behavior: it can produce identical pipelines for two different MeshVertexBufferLayouts. To optimize the number of active pipelines / reduce re-binds while drawing, I de-duplicate pipelines post-specialization using the final `VertexBufferLayout` as the key.  For example, consider a pipeline that needs the layout `(position, normal)` and is specialized using two meshes: `(position, normal, uv)` and `(position, normal, other_vec2)`. If both of these meshes result in `(position, normal)` specializations, we can use the same pipeline! Now we do. Cool!

To briefly illustrate, this is what the relevant section of `MeshPipeline`'s specialization code looks like now:

```rust
impl SpecializedMeshPipeline for MeshPipeline {
    type Key = MeshPipelineKey;

    fn specialize(
        &self,
        key: Self::Key,
        layout: &MeshVertexBufferLayout,
    ) -> RenderPipelineDescriptor {
        let mut vertex_attributes = vec![
            Mesh::ATTRIBUTE_POSITION.at_shader_location(0),
            Mesh::ATTRIBUTE_NORMAL.at_shader_location(1),
            Mesh::ATTRIBUTE_UV_0.at_shader_location(2),
        ];

        let mut shader_defs = Vec::new();
        if layout.contains(Mesh::ATTRIBUTE_TANGENT) {
            shader_defs.push(String::from("VERTEX_TANGENTS"));
            vertex_attributes.push(Mesh::ATTRIBUTE_TANGENT.at_shader_location(3));
        }

        let vertex_buffer_layout = layout
            .get_layout(&vertex_attributes)
            .expect("Mesh is missing a vertex attribute");
```

Notice that this is _much_ simpler than it was before. And now any mesh with any layout can be used with this pipeline, provided it has vertex postions, normals, and uvs. We even got to remove `HAS_TANGENTS` from MeshPipelineKey and `has_tangents` from `GpuMesh`, because that information is redundant with `MeshVertexBufferLayout`.

This is still a draft because I still need to:

* Add more docs
* Experiment with adding error handling to mesh pipeline specialization (which would print errors at runtime when a mesh is missing a vertex attribute required by a pipeline). If it doesn't tank perf, we'll keep it.
* Consider breaking out the PreHash / hashbrown changes into a separate PR.
* Add an example illustrating this change
* Verify that the "mesh-specialized pipeline de-duplication code" works properly

Please dont yell at me for not doing these things yet :) Just trying to get this in peoples' hands asap.

Alternative to #3120
Fixes #3030


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-02-23 23:21:13 +00:00
Carter Anderson
98938a8555 Internal Asset Hot Reloading (#3966)
Adds "hot reloading" of internal assets, which is normally not possible because they are loaded using `include_str` / direct Asset collection access.

This is accomplished via the following:
* Add a new `debug_asset_server` feature flag
* When that feature flag is enabled, create a second App with a second AssetServer that points to a configured location (by default the `crates` folder). Plugins that want to add hot reloading support for their assets can call the new `app.add_debug_asset::<T>()` and `app.init_debug_asset_loader::<T>()` functions.
* Load "internal" assets using the new `load_internal_asset` macro. By default this is identical to the current "include_str + register in asset collection" approach. But if the `debug_asset_server` feature flag is enabled, it will also load the asset dynamically in the debug asset server using the file path. It will then set up a correlation between the "debug asset" and the "actual asset" by listening for asset change events.

This is an alternative to #3673. The goal was to keep the boilerplate and features flags to a minimum for bevy plugin authors, and allow them to home their shaders near relevant code. 

This is a draft because I haven't done _any_ quality control on this yet. I'll probably rename things and remove a bunch of unwraps. I just got it working and wanted to use it to start a conversation.

Fixes #3660
2022-02-18 22:56:57 +00:00
dataphract
b506c30cd3 fix: only init_resource() once for AmbientLight (#3853)
# Objective

`PbrPlugin` calls `app.init_resource::<AmbientLight>()` twice. The second call won't do anything.

## Solution

Remove the second call.
2022-02-03 00:43:37 +00:00
Hennadii Chernyshchyk
458cb7a9e9 Add headless mode (#3439)
# Objective

In this PR I added the ability to opt-out graphical backends. Closes #3155.

## Solution

I turned backends into `Option` ~~and removed panicking sub app API to force users handle the error (was suggested by `@cart`)~~.
2022-01-08 10:39:43 +00:00