Commit graph

80 commits

Author SHA1 Message Date
Robert Swain
0a11af9375
Reduce the size of MeshUniform to improve performance (#9416)
# Objective

- Significantly reduce the size of MeshUniform by only including
necessary data.

## Solution

Local to world, model transforms are affine. This means they only need a
4x3 matrix to represent them.

`MeshUniform` stores the current, and previous model transforms, and the
inverse transpose of the current model transform, all as 4x4 matrices.
Instead we can store the current, and previous model transforms as 4x3
matrices, and we only need the upper-left 3x3 part of the inverse
transpose of the current model transform. This change allows us to
reduce the serialized MeshUniform size from 208 bytes to 144 bytes,
which is over a 30% saving in data to serialize, and VRAM bandwidth and
space.

## Benchmarks

On an M1 Max, running `many_cubes -- sphere`, main is in yellow, this PR
is in red:
<img width="1484" alt="Screenshot 2023-08-11 at 02 36 43"
src="https://github.com/bevyengine/bevy/assets/302146/7d99c7b3-f2bb-4004-a8d0-4c00f755cb0d">
A reduction in frame time of ~14%.

---

## Changelog

- Changed: Redefined `MeshUniform` to improve performance by using 4x3
affine transforms and reconstructing 4x4 matrices in the shader. Helper
functions were added to `bevy_pbr::mesh_functions` to unpack the data.
`affine_to_square` converts the packed 4x3 in 3x4 matrix data to a 4x4
matrix. `mat2x4_f32_to_mat3x3` converts the 3x3 in mat2x4 + f32 matrix
data back into a 3x3.

## Migration Guide

Shader code before:
```
var model = mesh[instance_index].model;
```

Shader code after:
```
#import bevy_pbr::mesh_functions affine_to_square

var model = affine_to_square(mesh[instance_index].model);
```
2023-08-15 06:00:23 +00:00
Robert Swain
e6405bb7b4
Use GpuArrayBuffer for MeshUniform (#9254)
# Objective

- Reduce the number of rebindings to enable batching of draw commands

## Solution

- Use the new `GpuArrayBuffer` for `MeshUniform` data to store all
`MeshUniform` data in arrays within fewer bindings
- Sort opaque/alpha mask prepass, opaque/alpha mask main, and shadow
phases also by the batch per-object data binding dynamic offset to
improve performance on WebGL2.

---

## Changelog

- Changed: Per-object `MeshUniform` data is now managed by
`GpuArrayBuffer` as arrays in buffers that need to be indexed into.

## Migration Guide

Accessing the `model` member of an individual mesh object's shader
`Mesh` struct the old way where each `MeshUniform` was stored at its own
dynamic offset:
```rust
struct Vertex {
    @location(0) position: vec3<f32>,
};

fn vertex(vertex: Vertex) -> VertexOutput {
    var out: VertexOutput;
    out.clip_position = mesh_position_local_to_clip(
        mesh.model,
        vec4<f32>(vertex.position, 1.0)
    );
    return out;
}
```

The new way where one needs to index into the array of `Mesh`es for the
batch:
```rust
struct Vertex {
    @builtin(instance_index) instance_index: u32,
    @location(0) position: vec3<f32>,
};

fn vertex(vertex: Vertex) -> VertexOutput {
    var out: VertexOutput;
    out.clip_position = mesh_position_local_to_clip(
        mesh[vertex.instance_index].model,
        vec4<f32>(vertex.position, 1.0)
    );
    return out;
}
```
Note that using the instance_index is the default way to pass the
per-object index into the shader, but if you wish to do custom rendering
approaches you can pass it in however you like.

---------

Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com>
2023-07-30 13:17:08 +00:00
Nicola Papale
c6170d48f9
Add morph targets (#8158)
# Objective

- Add morph targets to `bevy_pbr` (closes #5756) & load them from glTF
- Supersedes #3722
- Fixes #6814

[Morph targets][1] (also known as shape interpolation, shape keys, or
blend shapes) allow animating individual vertices with fine grained
controls. This is typically used for facial expressions. By specifying
multiple poses as vertex offset, and providing a set of weight of each
pose, it is possible to define surprisingly realistic transitions
between poses. Blending between multiple poses also allow composition.
Morph targets are part of the [gltf standard][2] and are a feature of
Unity and Unreal, and babylone.js, it is only natural to implement them
in bevy.

## Solution

This implementation of morph targets uses a 3d texture where each pixel
is a component of an animated attribute. Each layer is a different
target. We use a 2d texture for each target, because the number of
attribute×components×animated vertices is expected to always exceed the
maximum pixel row size limit of webGL2. It copies fairly closely the way
skinning is implemented on the CPU side, while on the GPU side, the
shader morph target implementation is a relatively trivial detail.

We add an optional `morph_texture` to the `Mesh` struct. The
`morph_texture` is built through a method that accepts an iterator over
attribute buffers.

The `MorphWeights` component, user-accessible, controls the blend of
poses used by mesh instances (so that multiple copy of the same mesh may
have different weights), all the weights are uploaded to a uniform
buffer of 256 `f32`. We limit to 16 poses per mesh, and a total of 256
poses.

More literature:
* Old babylone.js implementation (vertex attribute-based):
https://www.eternalcoding.com/dev-log-1-morph-targets/
* Babylone.js implementation (similar to ours):
https://www.youtube.com/watch?v=LBPRmGgU0PE
* GPU gems 3:
https://developer.nvidia.com/gpugems/gpugems3/part-i-geometry/chapter-3-directx-10-blend-shapes-breaking-limits
* Development discord thread
https://discord.com/channels/691052431525675048/1083325980615114772


https://user-images.githubusercontent.com/26321040/231181046-3bca2ab2-d4d9-472e-8098-639f1871ce2e.mp4


https://github.com/bevyengine/bevy/assets/26321040/d2a0c544-0ef8-45cf-9f99-8c3792f5a258

## Acknowledgements

* Thanks to `storytold` for sponsoring the feature
* Thanks to `superdump` and `james7132` for guidance and help figuring
out stuff

## Future work

- Handling of less and more attributes (eg: animated uv, animated
arbitrary attributes)
- Dynamic pose allocation (so that zero-weighted poses aren't uploaded
to GPU for example, enables much more total poses)
- Better animation API, see #8357

----

## Changelog

- Add morph targets to bevy meshes
- Support up to 64 poses per mesh of individually up to 116508 vertices,
animation currently strictly limited to the position, normal and tangent
attributes.
	- Load a morph target using `Mesh::set_morph_targets` 
- Add `VisitMorphTargets` and `VisitMorphAttributes` traits to
`bevy_render`, this allows defining morph targets (a fairly complex and
nested data structure) through iterators (ie: single copy instead of
passing around buffers), see documentation of those traits for details
- Add `MorphWeights` component exported by `bevy_render`
- `MorphWeights` control mesh's morph target weights, blending between
various poses defined as morph targets.
- `MorphWeights` are directly inherited by direct children (single level
of hierarchy) of an entity. This allows controlling several mesh
primitives through a unique entity _as per GLTF spec_.
- Add `MorphTargetNames` component, naming each indices of loaded morph
targets.
- Load morph targets weights and buffers in `bevy_gltf` 
- handle morph targets animations in `bevy_animation` (previously, it
was a `warn!` log)
- Add the `MorphStressTest.gltf` asset for morph targets testing, taken
from the glTF samples repo, CC0.
- Add morph target manipulation to `scene_viewer`
- Separate the animation code in `scene_viewer` from the rest of the
code, reducing `#[cfg(feature)]` noise
- Add the `morph_targets.rs` example to show off how to manipulate morph
targets, loading `MorpStressTest.gltf`

## Migration Guide

- (very specialized, unlikely to be touched by 3rd parties)
- `MeshPipeline` now has a single `mesh_layouts` field rather than
separate `mesh_layout` and `skinned_mesh_layout` fields. You should
handle all possible mesh bind group layouts in your implementation
- You should also handle properly the new `MORPH_TARGETS` shader def and
mesh pipeline key. A new function is exposed to make this easier:
`setup_moprh_and_skinning_defs`
- The `MeshBindGroup` is now `MeshBindGroups`, cached bind groups are
now accessed through the `get` method.

[1]: https://en.wikipedia.org/wiki/Morph_target_animation
[2]:
https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#morph-targets

---------

Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-06-22 20:00:01 +00:00
Edgar Geier
f18f28874a
Allow tuples and single plugins in add_plugins, deprecate add_plugin (#8097)
# Objective

- Better consistency with `add_systems`.
- Deprecating `add_plugin` in favor of a more powerful `add_plugins`.
- Allow passing `Plugin` to `add_plugins`.
- Allow passing tuples to `add_plugins`.

## Solution

- `App::add_plugins` now takes an `impl Plugins` parameter.
- `App::add_plugin` is deprecated.
- `Plugins` is a new sealed trait that is only implemented for `Plugin`,
`PluginGroup` and tuples over `Plugins`.
- All examples, benchmarks and tests are changed to use `add_plugins`,
using tuples where appropriate.

---

## Changelog

### Changed

- `App::add_plugins` now accepts all types that implement `Plugins`,
which is implemented for:
  - Types that implement `Plugin`.
  - Types that implement `PluginGroup`.
  - Tuples (up to 16 elements) over types that implement `Plugins`.
- Deprecated `App::add_plugin` in favor of `App::add_plugins`.

## Migration Guide

- Replace `app.add_plugin(plugin)` calls with `app.add_plugins(plugin)`.

---------

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-06-21 20:51:03 +00:00
JMS55
af9c945f40
Screen Space Ambient Occlusion (SSAO) MVP (#7402)
![image](https://github.com/bevyengine/bevy/assets/47158642/dbb62645-f639-4f2b-b84b-26fd915c186d)

# Objective

- Add Screen space ambient occlusion (SSAO). SSAO approximates
small-scale, local occlusion of _indirect_ diffuse light between
objects. SSAO does not apply to direct lighting, such as point or
directional lights.
- This darkens creases, e.g. on staircases, and gives nice contact
shadows where objects meet, giving entities a more "grounded" feel.
- Closes https://github.com/bevyengine/bevy/issues/3632.

## Solution

- Implement the GTAO algorithm.
-
https://www.activision.com/cdn/research/Practical_Real_Time_Strategies_for_Accurate_Indirect_Occlusion_NEW%20VERSION_COLOR.pdf
-
https://blog.selfshadow.com/publications/s2016-shading-course/activision/s2016_pbs_activision_occlusion.pdf
- Source code heavily based on [Intel's
XeGTAO](0d177ce06b/Source/Rendering/Shaders/XeGTAO.hlsli).
- Add an SSAO bevy example.

## Algorithm Overview
* Run a depth and normal prepass
* Create downscaled mips of the depth texture (preprocess_depths pass)
* GTAO pass - for each pixel, take several random samples from the
depth+normal buffers, reconstruct world position, raytrace in screen
space to estimate occlusion. Rather then doing completely random samples
on a hemisphere, you choose random _slices_ of the hemisphere, and then
can analytically compute the full occlusion of that slice. Also compute
edges based on depth differences here.
* Spatial denoise pass - bilateral blur, using edge detection to not
blur over edges. This is the final SSAO result.
* Main pass - if SSAO exists, sample the SSAO texture, and set occlusion
to be the minimum of ssao/material occlusion. This then feeds into the
rest of the PBR shader as normal.

---

## Future Improvements
- Maybe remove the low quality preset for now (too noisy)
- WebGPU fallback (see below)
- Faster depth->world position (see reverted code)
- Bent normals 
- Try interleaved gradient noise or spatiotemporal blue noise
- Replace the spatial denoiser with a combined spatial+temporal denoiser
- Render at half resolution and use a bilateral upsample
- Better multibounce approximation
(https://drive.google.com/file/d/1SyagcEVplIm2KkRD3WQYSO9O0Iyi1hfy/view)

## Far-Future Performance Improvements
- F16 math (missing naga-wgsl support
https://github.com/gfx-rs/naga/issues/1884)
- Faster coordinate space conversion for normals
- Faster depth mipchain creation
(https://github.com/GPUOpen-Effects/FidelityFX-SPD) (wgpu/naga does not
currently support subgroup ops)
- Deinterleaved SSAO for better cache efficiency
(https://developer.nvidia.com/sites/default/files/akamai/gameworks/samples/DeinterleavedTexturing.pdf)

## Other Interesting Papers
- Visibility bitmask
(https://link.springer.com/article/10.1007/s00371-022-02703-y,
https://cdrinmatane.github.io/posts/cgspotlight-slides/)
- Screen space diffuse lighting
(https://github.com/Patapom/GodComplex/blob/master/Tests/TestHBIL/2018%20Mayaux%20-%20Horizon-Based%20Indirect%20Lighting%20(HBIL).pdf)

## Platform Support
* SSAO currently does not work on DirectX12 due to issues with wgpu and
naga:
  * https://github.com/gfx-rs/wgpu/pull/3798
  * https://github.com/gfx-rs/naga/pull/2353
* SSAO currently does not work on WebGPU because r16float is not a valid
storage texture format
https://gpuweb.github.io/gpuweb/wgsl/#storage-texel-formats. We can fix
this with a fallback to r32float.

---

## Changelog

- Added ScreenSpaceAmbientOcclusionSettings,
ScreenSpaceAmbientOcclusionQualityLevel, and
ScreenSpaceAmbientOcclusionBundle

---------

Co-authored-by: IceSentry <c.giguere42@gmail.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
Co-authored-by: Daniel Chia <danstryder@gmail.com>
Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com>
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Brandon Dyer <brandondyer64@gmail.com>
Co-authored-by: Edgar Geier <geieredgar@gmail.com>
Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-06-18 21:05:55 +00:00
radiish
1efc762924
reflect: stable type path v2 (#7184)
# Objective

- Introduce a stable alternative to
[`std::any::type_name`](https://doc.rust-lang.org/std/any/fn.type_name.html).
- Rewrite of #5805 with heavy inspiration in design.
- On the path to #5830.
- Part of solving #3327.


## Solution

- Add a `TypePath` trait for static stable type path/name information.
- Add a `TypePath` derive macro.
- Add a `impl_type_path` macro for implementing internal and foreign
types in `bevy_reflect`.

---

## Changelog

- Added `TypePath` trait.
- Added `DynamicTypePath` trait and `get_type_path` method to `Reflect`.
- Added a `TypePath` derive macro.
- Added a `bevy_reflect::impl_type_path` for implementing `TypePath` on
internal and foreign types in `bevy_reflect`.
- Changed `bevy_reflect::utility::(Non)GenericTypeInfoCell` to
`(Non)GenericTypedCell<T>` which allows us to be generic over both
`TypeInfo` and `TypePath`.
- `TypePath` is now a supertrait of `Asset`, `Material` and
`Material2d`.
- `impl_reflect_struct` needs a `#[type_path = "..."]` attribute to be
specified.
- `impl_reflect_value` needs to either specify path starting with a
double colon (`::core::option::Option`) or an `in my_crate::foo`
declaration.
- Added `bevy_reflect_derive::ReflectTypePath`.
- Most uses of `Ident` in `bevy_reflect_derive` changed to use
`ReflectTypePath`.

## Migration Guide

- Implementors of `Asset`, `Material` and `Material2d` now also need to
derive `TypePath`.
- Manual implementors of `Reflect` will need to implement the new
`get_type_path` method.

## Open Questions
- [x] ~This PR currently does not migrate any usages of
`std::any::type_name` to use `bevy_reflect::TypePath` to ease the review
process. Should it?~ Migration will be left to a follow-up PR.
- [ ] This PR adds a lot of `#[derive(TypePath)]` and `T: TypePath` to
satisfy new bounds, mostly when deriving `TypeUuid`. Should we make
`TypePath` a supertrait of `TypeUuid`? [Should we remove `TypeUuid` in
favour of
`TypePath`?](2afbd85532 (r961067892))
2023-06-05 20:31:20 +00:00
Marco Buono
292e069bb5
Apply codebase changes in preparation for StandardMaterial transmission (#8704)
# Objective

- Make #8015 easier to review;

## Solution

- This commit contains changes not directly related to transmission
required by #8015, in easier-to-review, one-change-per-commit form.

---

## Changelog

### Fixed

- Clear motion vector prepass using `0.0` instead of `1.0`, to avoid TAA
artifacts on transparent objects against the background;

### Added

- The `E` mathematical constant is now available for use in shaders,
exposed under `bevy_pbr::utils`;
- A new `TAA` shader def is now available, for conditionally enabling
shader logic via `#ifdef` when TAA is enabled; (e.g. for jittering
texture samples)
- A new `FallbackImageZero` resource is introduced, for when a fallback
image filled with zeroes is required;
- A new `RenderPhase<I>::render_range()` method is introduced, for
render phases that need to render their items in multiple parceled out
“steps”;

### Changed

- The `MainTargetTextures` struct now holds both `Texture` and
`TextureViews` for the main textures;
- The fog shader functions under `bevy_pbr::fog` now take the a `Fog`
structure as their first argument, instead of relying on the global
`fog` uniform;
- The main textures can now be used as copy sources;

## Migration Guide

- `ViewTarget::main_texture()` and `ViewTarget::main_texture_other()`
now return `&Texture` instead of `&TextureView`. If you were relying on
these methods, replace your usage with
`ViewTarget::main_texture_view()`and
`ViewTarget::main_texture_other_view()`, respectively;
- `ViewTarget::sampled_main_texture()` now returns `Option<&Texture>`
instead of a `Option<&TextureView>`. If you were relying on this method,
replace your usage with `ViewTarget::sampled_main_texture_view()`;
- The `apply_fog()`, `linear_fog()`, `exponential_fog()`,
`exponential_squared_fog()` and `atmospheric_fog()` functions now take a
configurable `Fog` struct. If you were relying on them, update your
usage by adding the global `fog` uniform as their first argument;
2023-05-30 14:21:53 +00:00
Marco Buono
4465f256eb
Add MAY_DISCARD shader def, enabling early depth tests for most cases (#6697)
# Objective

- Right now we can't really benefit from [early depth
testing](https://www.khronos.org/opengl/wiki/Early_Fragment_Test) in our
PBR shader because it includes codepaths with `discard`, even for
situations where they are not necessary.

## Solution

- This PR introduces a new `MeshPipelineKey` and shader def,
`MAY_DISCARD`;
- All possible material/mesh options that that may result in `discard`s
being needed must set `MAY_DISCARD` ahead of time:
- Right now, this is only `AlphaMode::Mask(f32)`, but in the future
might include other options/effects; (e.g. one effect I'm personally
interested in is bayer dither pseudo-transparency for LOD transitions of
opaque meshes)
- Shader codepaths that can `discard` are guarded by an `#ifdef
MAY_DISCARD` preprocessor directive:
  - Right now, this is just one branch in `alpha_discard()`;
- If `MAY_DISCARD` is _not_ set, the `@early_depth_test` attribute is
added to the PBR fragment shader. This is a not yet documented, possibly
non-standard WGSL extension I found browsing Naga's source code. [I
opened a PR to document it
there](https://github.com/gfx-rs/naga/pull/2132). My understanding is
that for backends where this attribute is supported, it will force an
explicit opt-in to early depth test. (e.g. via
`layout(early_fragment_tests) in;` in GLSL)

## Caveats

- I included `@early_depth_test` for the sake of us being explicit, and
avoiding the need for the driver to be “smart” about enabling this
feature. That way, if we make a mistake and include a `discard`
unguarded by `MAY_DISCARD`, it will either produce errors or noticeable
visual artifacts so that we'll catch early, instead of causing a
performance regression.
- I'm not sure explicit early depth test is supported on the naga Metal
backend, which is what I'm currently using, so I can't really test the
explicit early depth test enable, I would like others with Vulkan/GL
hardware to test it if possible;
- I would like some guidance on how to measure/verify the performance
benefits of this;
- If I understand it correctly, this, or _something like this_ is needed
to fully reap the performance gains enabled by #6284;
- This will _most definitely_ conflict with #6284 and #6644. I can fix
the conflicts as needed, depending on whether/the order they end up
being merging in.

---

## Changelog

### Changed

- Early depth tests are now enabled whenever possible for meshes using
`StandardMaterial`, reducing the number of fragments evaluated for
scenes with lots of occlusions.
2023-05-29 15:15:01 +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
IceSentry
0859f675c3
Use the prepass normal texture in main pass when possible (#8231)
# Objective

- We support enabling a normal prepass, but the main pass never actually
uses it and recomputes the normals in the main pass. This isn't ideal
since it's doing redundant work.

## Solution

- Use the normal texture from the prepass in the main pass

## Notes

~~I used `NORMAL_PREPASS_ENABLED` as a shader_def because
`NORMAL_PREPASS` is currently used to signify that it is running in the
prepass while this shader_def need to indicate the prepass is done and
the normal prepass was ran before. I'm not sure if there's a better way
to name this.~~
2023-03-29 18:04:40 +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
JoJoJet
fd1af7c8b8
Replace multiple calls to add_system with add_systems (#8001) 2023-03-10 18:15:22 +00:00
robtfm
6124b20f4b use blendstate blend for alphamode::blend (#7899)
# Objective

revert combining pipelines for AlphaMode::Blend and AlphaMode::Premultiplied & Add

the recent blend state pr changed `AlphaMode::Blend` to use a blend state of `Blend::PREMULTIPLIED_ALPHA_BLENDING`, and recovered the original behaviour by multiplying colour by alpha in the standard material's fragment shader. 

this had some advantages (specifically it means more material instances can be batched together in future), but this also means that custom materials that specify `AlphaMode::Blend` now get a premultiplied blend state, so they must also multiply colour by alpha.

## Solution

revert that combination to preserve 0.9 behaviour for custom materials with AlphaMode::Blend.
2023-03-05 00:17:44 +00:00
robtfm
6beca13553 add standard material depth bias to pipeline (#7847)
# Objective

the current depth bias only adjusts ordering, so it doesn't work for opaque meshes vs alpha-blend meshes, and it doesn't help when two meshes are infinitesimally offset from one another.

## Solution

pass the material's depth bias into the pipeline depth stencil `constant` field.
2023-03-04 12:29:09 +00:00
Edgar Geier
cb0db07c5b Fix dependency of shadow mapping on the optional PrepassPlugin (#7878)
# Objective

Unfortunately, there are three issues with my changes introduced by #7784.

1.  The changes left some dead code. This is already taken care of here: #7875.
2. Disabling prepass causes failures because the shadow mapping relies on the `PrepassPlugin` now.
3. Custom materials use the `prepass.wgsl` shader, but this does not always define a fragment entry point.

This PR fixes 2. and 3. and resolves #7879.

## Solution

- Add a regression test with disabled prepass.
- Split `PrepassPlugin` into two plugins:
  - `PrepassPipelinePlugin` contains the part that is required for the shadow mapping to work and is unconditionally added.
  - `PrepassPlugin` now only adds the systems and resources required for the "real" prepasses.
- Add a noop fragment entry point to `prepass.wgsl`, used if `NORMAL_PASS` is not defined.


Co-authored-by: Edgar Geier <geieredgar@gmail.com>
2023-03-03 15:08:54 +00:00
JMS55
fc7a3bdfc2 Remove dead code after #7784 (#7875)
# Objective

- Remove dead code after #7784

# Changelog
- Removed `SetShadowViewBindGroup`, `queue_shadow_view_bind_group()`, and `LightMeta::shadow_view_bind_group` in favor of reusing the prepass view bind group.

# Migration Guide
- Removed `SetShadowViewBindGroup`, `queue_shadow_view_bind_group()`, and `LightMeta::shadow_view_bind_group` in favor of reusing the prepass view bind group.
2023-03-02 22:44:10 +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
Griffin
912fb58869 Initial tonemapping options (#7594)
# Objective

Splits tone mapping from https://github.com/bevyengine/bevy/pull/6677 into a separate PR.
Address https://github.com/bevyengine/bevy/issues/2264.
Adds tone mapping options:
- None: Bypasses tonemapping for instances where users want colors output to match those set.
- Reinhard
- Reinhard Luminance: Bevy's exiting tonemapping
- [ACES](https://github.com/TheRealMJP/BakingLab/blob/master/BakingLab/ACES.hlsl) (Fitted version, based on the same implementation that Godot 4 uses) see https://github.com/bevyengine/bevy/issues/2264
- [AgX](https://github.com/sobotka/AgX)
- SomewhatBoringDisplayTransform
- TonyMcMapface
- Blender Filmic

This PR also adds support for EXR images so they can be used to compare tonemapping options with reference images.

## Migration Guide
- Tonemapping is now an enum with NONE and the various tonemappers.
- The DebandDither is now a separate component.




Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2023-02-19 20:38:13 +00:00
Zhixing Zhang
16feb9acb7 Add push contant config to layout (#7681)
# Objective

Allow for creating pipelines that use push constants. To be able to use push constants. Fixes #4825

As of right now, trying to call `RenderPass::set_push_constants` will trigger the following error:

```
thread 'main' panicked at 'wgpu error: Validation Error

Caused by:
    In a RenderPass
      note: encoder = `<CommandBuffer-(0, 59, Vulkan)>`
    In a set_push_constant command
    provided push constant is for stage(s) VERTEX | FRAGMENT | VERTEX_FRAGMENT, however the pipeline layout has no push constant range for the stage(s) VERTEX | FRAGMENT | VERTEX_FRAGMENT
```
## Solution

Add a field push_constant_ranges to` RenderPipelineDescriptor` and `ComputePipelineDescriptor`.

This PR supersedes #4908 which now contains merge conflicts due to significant changes to `bevy_render`.

Meanwhile, this PR also made the `layout` field of `RenderPipelineDescriptor` and `ComputePipelineDescriptor` non-optional. If the user do not need to specify the bind group layouts, they can simply supply an empty vector here. No need for it to be optional.

---

## Changelog
- Add a field push_constant_ranges to RenderPipelineDescriptor and ComputePipelineDescriptor
- Made the `layout` field of RenderPipelineDescriptor and ComputePipelineDescriptor non-optional.


## Migration Guide

- Add push_constant_ranges: Vec::new() to every `RenderPipelineDescriptor` and `ComputePipelineDescriptor`
- Unwrap the optional values on the `layout` field of `RenderPipelineDescriptor` and `ComputePipelineDescriptor`. If the descriptor has no layout, supply an empty vector.


Co-authored-by: Zhixing Zhang <me@neoto.xin>
2023-02-17 06:20:16 +00:00
Niklas Eicker
0bce78439b Cleanup system sets called labels (#7678)
# Objective

We have a few old system labels that are now system sets but are still named or documented as labels. Documentation also generally mentioned system labels in some places.


## Solution

- Clean up naming and documentation regarding system sets

## Migration Guide

`PrepareAssetLabel` is now called `PrepareAssetSet`
2023-02-14 21:46:07 +00:00
Kurt Kühnert
d7d983be60 Reusable Material Pipeline (#7548)
# Objective

- rebased version of #6155

The `MaterialPipeline` cannot be integrated into other pipelines like the `MeshPipeline`.

## Solution

Implement `Clone` for `MaterialPipeline`. Expose systems and resources part of the `MaterialPlugin` to allow custom assembly - especially combining existing systems and resources with a custom `queue_material_meshes` system.


# Changelog
## Added

- Clone impl for MaterialPipeline

## Changed

- ExtractedMaterials, extract_materials and prepare_materials are now public
2023-02-13 19:33:51 +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
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
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
Marco Buono
603cb439d9 Standard Material Blend Modes (#6644)
# Objective

- This PR adds support for blend modes to the PBR `StandardMaterial`.

<img width="1392" alt="Screenshot 2022-11-18 at 20 00 56" src="https://user-images.githubusercontent.com/418473/202820627-0636219a-a1e5-437a-b08b-b08c6856bf9c.png">

<img width="1392" alt="Screenshot 2022-11-18 at 20 01 01" src="https://user-images.githubusercontent.com/418473/202820615-c8d43301-9a57-49c4-bd21-4ae343c3e9ec.png">

## Solution

- The existing `AlphaMode` enum is extended, adding three more modes: `AlphaMode::Premultiplied`, `AlphaMode::Add` and `AlphaMode::Multiply`;
- All new modes are rendered in the existing `Transparent3d` phase;
- The existing mesh flags for alpha mode are reorganized for a more compact/efficient representation, and new values are added;
- `MeshPipelineKey::TRANSPARENT_MAIN_PASS` is refactored into `MeshPipelineKey::BLEND_BITS`.
  -  `AlphaMode::Opaque` and `AlphaMode::Mask(f32)` share a single opaque pipeline key: `MeshPipelineKey::BLEND_OPAQUE`;
  - `Blend`, `Premultiplied` and `Add` share a single premultiplied alpha pipeline key, `MeshPipelineKey::BLEND_PREMULTIPLIED_ALPHA`. In the shader, color values are premultiplied accordingly (or not) depending on the blend mode to produce the three different results after PBR/tone mapping/dithering;
  - `Multiply` uses its own independent pipeline key, `MeshPipelineKey::BLEND_MULTIPLY`;
- Example and documentation are provided.
---

## Changelog

### Added

- Added support for additive and multiplicative blend modes in the PBR `StandardMaterial`, via `AlphaMode::Add` and `AlphaMode::Multiply`;
- Added support for premultiplied alpha in the PBR `StandardMaterial`, via `AlphaMode::Premultiplied`;
2023-01-21 21:46:53 +00:00
Sjael
06ada2e93d Changed Msaa to Enum (#7292)
# Objective

Fixes #6931 

Continues #6954 by squashing `Msaa` to a flat enum

Helps out  #7215 

# Solution
```
pub enum Msaa {
    Off = 1,
    #[default]
    Sample4 = 4,
}
```

# Changelog

- Modified
    - `Msaa` is now enum
    - Defaults to 4 samples
    - Uses `.samples()` method to get the sample number as `u32`

# Migration Guide
```
let multi = Msaa { samples: 4 } 
// is now
let multi = Msaa::Sample4

multi.samples
// is now
multi.samples()
```



Co-authored-by: Sjael <jakeobrien44@gmail.com>
2023-01-20 14:25:21 +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
Daniel Chia
517deda215 Make PipelineCache internally mutable. (#7205)
# Objective

- Allow rendering queue systems to use a `Res<PipelineCache>` even for queueing up new rendering pipelines. This is part of unblocking parallel execution queue systems.

## Solution

- Make `PipelineCache` internally mutable w.r.t to queueing new pipelines. Pipelines are no longer immediately updated into the cache state, but rather queued into a Vec. The Vec of pending new pipelines is then later processed at the same time we actually create the queued pipelines on the GPU device.

---

## Changelog

`PipelineCache` no longer requires mutable access in order to queue render / compute pipelines.

## Migration Guide

* Most usages of `resource_mut::<PipelineCache>` and `ResMut<PipelineCache>` can be changed to `resource::<PipelineCache>` and `Res<PipelineCache>` as long as they don't use any methods requiring mutability - the only public method requiring it is `process_queue`.
2023-01-16 15:41:14 +00:00
Sludge
908c40dd88 Implement Clone for all pipeline types (#6653)
# Objective

Pipelines can be customized by wrapping an existing pipeline in a newtype and adding custom logic to its implementation of `SpecializedMeshPipeline::specialize`. To make that easier, the wrapped pipeline type needs to implement `Clone`.

For example, the current non-cloneable pipelines require wrapper pipelines to pull apart the wrapped pipeline like this:

```rust
impl FromWorld for Wireframe2dPipeline {
    fn from_world(world: &mut World) -> Self {
        let p = &world.resource::<Material2dPipeline<ColorMaterial>>();
        Self {
            mesh2d_pipeline: p.mesh2d_pipeline.clone(),
            material2d_layout: p.material2d_layout.clone(),
            vertex_shader: p.vertex_shader.clone(),
            fragment_shader: p.fragment_shader.clone(),
        }
    }
}
```

## Solution

Derive or implement `Clone` on all built-in pipeline types. This is easy to do since they mostly just contain cheaply clonable reference-counted types.

---

## Changelog

Implement `Clone` for all pipeline types.
2023-01-14 18:33:38 +00:00
James Liu
2d727afaf7 Flatten render commands (#6885)
# Objective
Speed up the render phase of rendering. Simplify the trait structure for render commands.

## Solution

 - Merge `EntityPhaseItem` into `PhaseItem` (`EntityPhaseItem::entity` -> `PhaseItem::entity`)
 - Merge `EntityRenderCommand` into `RenderCommand`.
 - Add two associated types to `RenderCommand`: `RenderCommand::ViewWorldQuery` and `RenderCommand::WorldQuery`.
 - Use the new associated types to construct two `QueryStates`s for `RenderCommandState`.
 - Hoist any `SQuery<T>` fetches in `EntityRenderCommand`s into the aformentioned two queries. Batch fetch them all at once.

## Performance
`main_opaque_pass_3d` is slightly faster on `many_foxes` (427.52us -> 401.15us)

![image](https://user-images.githubusercontent.com/3137680/206359804-9928b20a-7d92-41f8-bf7d-6e8c5cc802f0.png)

The shadow pass node is also slightly faster (344.52 -> 338.24us)

![image](https://user-images.githubusercontent.com/3137680/206359977-1212198d-f933-49a0-80f1-62ff88eb5727.png)

## Future Work

 - Can we hoist the view level queries out of the core loop?

---

## Changelog
Added: `PhaseItem::entity`
Added: `RenderCommand::ViewWorldQuery` associated type.
Added: `RenderCommand::ItemorldQuery` associated type.
Added: `Draw<T>::prepare` optional trait function.
Removed: `EntityPhaseItem` trait

## Migration Guide
TODO
2023-01-04 01:13:30 +00:00
IceSentry
f119d9df8e Add DrawFunctionsInternals::id() (#6745)
# Objective

- Every usage of `DrawFunctionsInternals::get_id()` was followed by a `.unwrap()`. which just adds boilerplate.

## Solution

- Introduce a fallible version of `DrawFunctionsInternals::get_id()` and use it where possible.
- I also took the opportunity to improve the error message a little in the case where it fails.

---

## Changelog

- Added `DrawFunctionsInternals::id()`
2022-11-28 13:54:13 +00:00
IceSentry
64642fbd3c Remove unnecessary struct in Material AsBindGroup example (#6701)
# Objective

- Reduce confusion around uniform bindings in materials. I've seen multiple people on discord get confused by it because it uses a struct that is named the same in the rust code and the wgsl code, but doesn't contain the same data. Also, the only reason this works is mostly by chance because the memory happens to align correctly.

## Solution

- Remove the confusing parts of the doc

## Notes

It's not super clear in the diff why this causes confusion, but essentially, the rust code defines a `CustomMaterial` struct with a color and a texture, but in the wgsl code the struct with the same name only contains the color. People are confused by it because the struct in wgsl doesn't need to be there.

You _can_ have complex structs on each side and the macro will even combine it for you if you reuse a binding index, but as it is now, this example seems to confuse more than help people.
2022-11-28 13:15:03 +00:00
Aevyrie
72fbcc7633 Fix color banding by dithering image before quantization (#5264)
# Objective

- Closes #5262 
- Fix color banding caused by quantization.

## Solution

- Adds dithering to the tonemapping node from #3425.
- This is inspired by Godot's default "debanding" shader: https://gist.github.com/belzecue/
- Unlike Godot:
  - debanding happens after tonemapping. My understanding is that this is preferred, because we are running the debanding at the last moment before quantization (`[f32, f32, f32, f32]` -> `f32`). This ensures we aren't biasing the dithering strength by applying it in a different (linear) color space.
  - This code instead uses and reference the origin source, Valve at GDC 2015

![Screenshot from 2022-11-10 13-44-46](https://user-images.githubusercontent.com/2632925/201218880-70f4cdab-a1ed-44de-a88c-8759e77197f1.png)
![Screenshot from 2022-11-10 13-41-11](https://user-images.githubusercontent.com/2632925/201218883-72393352-b162-41da-88bb-6e54a1e26853.png)


## Additional Notes 

Real time rendering to standard dynamic range outputs is limited to 8 bits of depth per color channel. Internally we keep everything in full 32-bit precision (`vec4<f32>`) inside passes and 16-bit between passes until the image is ready to be displayed, at which point the GPU implicitly converts our `vec4<f32>` into a single 32bit value per pixel, with each channel (rgba) getting 8 of those 32 bits.

### The Problem

8 bits of color depth is simply not enough precision to make each step invisible - we only have 256 values per channel! Human vision can perceive steps in luma to about 14 bits of precision. When drawing a very slight gradient, the transition between steps become visible because with a gradient, neighboring pixels will all jump to the next "step" of precision at the same time.

### The Solution

One solution is to simply output in HDR - more bits of color data means the transition between bands will become smaller. However, not everyone has hardware that supports 10+ bit color depth. Additionally, 10 bit color doesn't even fully solve the issue, banding will result in coherent bands on shallow gradients, but the steps will be harder to perceive.

The solution in this PR adds noise to the signal before it is "quantized" or resampled from 32 to 8 bits. Done naively, it's easy to add unneeded noise to the image. To ensure dithering is correct and absolutely minimal, noise is adding *within* one step of the output color depth. When converting from the 32bit to 8bit signal, the value is rounded to the nearest 8 bit value (0 - 255). Banding occurs around the transition from one value to the next, let's say from 50-51. Dithering will never add more than +/-0.5 bits of noise, so the pixels near this transition might round to 50 instead of 51 but will never round more than one step. This means that the output image won't have excess variance:
  - in a gradient from 49 to 51, there will be a step between each band at 49, 50, and 51.
  - Done correctly, the modified image of this gradient will never have a adjacent pixels more than one step (0-255) from each other.
  - I.e. when scanning across the gradient you should expect to see:
```
                  |-band-| |-band-| |-band-|
Baseline:         49 49 49 50 50 50 51 51 51
Dithered:         49 50 49 50 50 51 50 51 51
Dithered (wrong): 49 50 51 49 50 51 49 51 50
```

![Screenshot from 2022-11-10 14-12-36](https://user-images.githubusercontent.com/2632925/201219075-ab3f46be-d4e9-4869-b66b-a92e1706f49e.png)
![Screenshot from 2022-11-10 14-11-48](https://user-images.githubusercontent.com/2632925/201219079-ec5d2add-817d-487a-8fc1-84569c9cda73.png)




You can see from above how correct dithering "fuzzes" the transition between bands to reduce distinct steps in color, without adding excess noise.

### HDR

The previous section (and this PR) assumes the final output is to an 8-bit texture, however this is not always the case. When Bevy adds HDR support, the dithering code will need to take the per-channel depth into account instead of assuming it to be 0-255. Edit: I talked with Rob about this and it seems like the current solution is okay. We may need to revisit once we have actual HDR final image output.

---

## Changelog

### Added

- All pipelines now support deband dithering. This is enabled by default in 3D, and can be toggled in the `Tonemapping` component in camera bundles. Banding is a graphical artifact created when the rendered image is crunched from high precision (f32 per color channel) down to the final output (u8 per channel in SDR). This results in subtle gradients becoming blocky due to the reduced color precision. Deband dithering applies a small amount of noise to the signal before it is "crunched", which breaks up the hard edges of blocks (bands) of color. Note that this does not add excess noise to the image, as the amount of noise is less than a single step of a color channel - just enough to break up the transition between color blocks in a gradient.


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-11-11 19:43:45 +00:00
TimJentzsch
694c980c82 Fix clippy::iter_with_drain (#6485)
# Objective

Fixes #6483.

- Fix the [`clippy::iter_with_drain`](https://rust-lang.github.io/rust-clippy/master/index.html#iter_with_drain) warnings
- From the docs: "`.into_iter()` is simpler with better performance"

## Solution

- Replace `.drain(..)` for `Vec` with `.into_iter()`
2022-11-06 01:42:15 +00:00
Jakob Hellermann
838b318863 separate tonemapping and upscaling passes (#3425)
Attempt to make features like bloom https://github.com/bevyengine/bevy/pull/2876 easier to implement.

**This PR:**
- Moves the tonemapping from `pbr.wgsl` into a separate pass
- also add a separate upscaling pass after the tonemapping which writes to the swap chain (enables resolution-independant rendering and post-processing after tonemapping)
- adds a `hdr` bool to the camera which controls whether the pbr and sprite shaders render into a `Rgba16Float` texture

**Open questions:**
- ~should the 2d graph work the same as the 3d one?~ it is the same now
- ~The current solution is a bit inflexible because while you can add a post processing pass that writes to e.g. the `hdr_texture`, you can't write to a separate `user_postprocess_texture` while reading the `hdr_texture` and tell the tone mapping pass to read from the `user_postprocess_texture` instead. If the tonemapping and upscaling render graph nodes were to take in a `TextureView` instead of the view entity this would almost work, but the bind groups for their respective input textures are already created in the `Queue` render stage in the hardcoded order.~ solved by creating bind groups in render node

**New render graph:**

![render_graph](https://user-images.githubusercontent.com/22177966/147767249-57dd4229-cfab-4ec5-9bf3-dc76dccf8e8b.png)
<details>
<summary>Before</summary>

![render_graph_old](https://user-images.githubusercontent.com/22177966/147284579-c895fdbd-4028-41cf-914c-e1ffef60e44e.png)
</details>

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-10-26 20:13:59 +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
01aedc8431 Spawn now takes a Bundle (#6054)
# Objective

Now that we can consolidate Bundles and Components under a single insert (thanks to #2975 and #6039), almost 100% of world spawns now look like `world.spawn().insert((Some, Tuple, Here))`. Spawning an entity without any components is an extremely uncommon pattern, so it makes sense to give spawn the "first class" ergonomic api. This consolidated api should be made consistent across all spawn apis (such as World and Commands).

## Solution

All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input:

```rust
// before:
commands
  .spawn()
  .insert((A, B, C));
world
  .spawn()
  .insert((A, B, C);

// after
commands.spawn((A, B, C));
world.spawn((A, B, C));
```

All existing instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api. A new `spawn_empty` has been added, replacing the old `spawn` api.  

By allowing `world.spawn(some_bundle)` to replace `world.spawn().insert(some_bundle)`, this opened the door to removing the initial entity allocation in the "empty" archetype / table done in `spawn()` (and subsequent move to the actual archetype in `.insert(some_bundle)`).

This improves spawn performance by over 10%:
![image](https://user-images.githubusercontent.com/2694663/191627587-4ab2f949-4ccd-4231-80eb-80dd4d9ad6b9.png)

To take this measurement, I added a new `world_spawn` benchmark.

Unfortunately, optimizing `Commands::spawn` is slightly less trivial, as Commands expose the Entity id of spawned entities prior to actually spawning. Doing the optimization would (naively) require assurances that the `spawn(some_bundle)` command is applied before all other commands involving the entity (which would not necessarily be true, if memory serves). Optimizing `Commands::spawn` this way does feel possible, but it will require careful thought (and maybe some additional checks), which deserves its own PR. For now, it has the same performance characteristics of the current `Commands::spawn_bundle` on main.

**Note that 99% of this PR is simple renames and refactors. The only code that needs careful scrutiny is the new `World::spawn()` impl, which is relatively straightforward, but it has some new unsafe code (which re-uses battle tested BundlerSpawner code path).** 

---

## Changelog

- All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input
- All instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api
- World and Commands now have `spawn_empty()`, which is equivalent to the old `spawn()` behavior.  

## Migration Guide

```rust
// Old (0.8):
commands
  .spawn()
  .insert_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));

// Old (0.8):
commands.spawn_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));

// Old (0.8):
let entity = commands.spawn().id();
// New (0.9)
let entity = commands.spawn_empty().id();

// Old (0.8)
let entity = world.spawn().id();
// New (0.9)
let entity = world.spawn_empty();
```
2022-09-23 19:55:54 +00:00
ira
992681b59b Make Resource trait opt-in, requiring #[derive(Resource)] V2 (#5577)
*This PR description is an edited copy of #5007, written by @alice-i-cecile.*
# Objective
Follow-up to https://github.com/bevyengine/bevy/pull/2254. The `Resource` trait currently has a blanket implementation for all types that meet its bounds.

While ergonomic, this results in several drawbacks:

* it is possible to make confusing, silent mistakes such as inserting a function pointer (Foo) rather than a value (Foo::Bar) as a resource
* it is challenging to discover if a type is intended to be used as a resource
* we cannot later add customization options (see the [RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/27-derive-component.md) for the equivalent choice for Component).
* dependencies can use the same Rust type as a resource in invisibly conflicting ways
* raw Rust types used as resources cannot preserve privacy appropriately, as anyone able to access that type can read and write to internal values
* we cannot capture a definitive list of possible resources to display to users in an editor
## Notes to reviewers
 * Review this commit-by-commit; there's effectively no back-tracking and there's a lot of churn in some of these commits.
   *ira: My commits are not as well organized :')*
 * I've relaxed the bound on Local to Send + Sync + 'static: I don't think these concerns apply there, so this can keep things simple. Storing e.g. a u32 in a Local is fine, because there's a variable name attached explaining what it does.
 * I think this is a bad place for the Resource trait to live, but I've left it in place to make reviewing easier. IMO that's best tackled with https://github.com/bevyengine/bevy/issues/4981.

## Changelog
`Resource` is no longer automatically implemented for all matching types. Instead, use the new `#[derive(Resource)]` macro.

## Migration Guide
Add `#[derive(Resource)]` to all types you are using as a resource.

If you are using a third party type as a resource, wrap it in a tuple struct to bypass orphan rules. Consider deriving `Deref` and `DerefMut` to improve ergonomics.

`ClearColor` no longer implements `Component`. Using `ClearColor` as a component in 0.8 did nothing.
Use the `ClearColorConfig` in the `Camera3d` and `Camera2d` components instead.


Co-authored-by: Alice <alice.i.cecile@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: devil-ira <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-08-08 21:36:35 +00:00
Timo Kösters
2ac744331b Fix shader syntax (#5613) 2022-08-08 19:59:59 +00:00
François
814f8d1635 update wgpu to 0.13 (#5168)
# Objective

- Update wgpu to 0.13
- ~~Wait, is wgpu 0.13 released? No, but I had most of the changes already ready since playing with webgpu~~ well it has been released now
- Also update parking_lot to 0.12 and naga to 0.9

## Solution

- Update syntax for wgsl shaders https://github.com/gfx-rs/wgpu/blob/master/CHANGELOG.md#wgsl-syntax
- Add a few options, remove some references: https://github.com/gfx-rs/wgpu/blob/master/CHANGELOG.md#other-breaking-changes
- fragment inputs should now exactly match vertex outputs for locations, so I added exports for those to be able to reuse them https://github.com/gfx-rs/wgpu/pull/2704
2022-07-14 21:17:16 +00:00
ira
4847f7e3ad Update codebase to use IntoIterator where possible. (#5269)
Remove unnecessary calls to `iter()`/`iter_mut()`.
Mainly updates the use of queries in our code, docs, and examples.

```rust
// From
for _ in list.iter() {
for _ in list.iter_mut() {

// To
for _ in &list {
for _ in &mut list {
```

We already enable the pedantic lint [clippy::explicit_iter_loop](https://rust-lang.github.io/rust-clippy/stable/) inside of Bevy. However, this only warns for a few known types from the standard library.

## Note for reviewers
As you can see the additions and deletions are exactly equal.
Maybe give it a quick skim to check I didn't sneak in a crypto miner, but you don't have to torture yourself by reading every line.
I already experienced enough pain making this PR :) 


Co-authored-by: devil-ira <justthecooldude@gmail.com>
2022-07-11 15:28:50 +00:00
Daniel McNab
7b2cf98896 Make RenderStage::Extract run on the render world (#4402)
# Objective

- Currently, the `Extract` `RenderStage` is executed on the main world, with the render world available as a resource.
- However, when needing access to resources in the render world (e.g. to mutate them), the only way to do so was to get exclusive access to the whole `RenderWorld` resource.
- This meant that effectively only one extract which wrote to resources could run at a time.
- We didn't previously make `Extract`ing writing to the world a non-happy path, even though we want to discourage that.

## Solution

- Move the extract stage to run on the render world.
- Add the main world as a `MainWorld` resource.
- Add an `Extract` `SystemParam` as a convenience to access a (read only) `SystemParam` in the main world during `Extract`.

## Future work

It should be possible to avoid needing to use `get_or_spawn` for the render commands, since now the `Commands`' `Entities` matches up with the world being executed on.
We need to determine how this interacts with https://github.com/bevyengine/bevy/pull/3519
It's theoretically possible to remove the need for the `value` method on `Extract`. However, that requires slightly changing the `SystemParam` interface, which would make it more complicated. That would probably mess up the `SystemState` api too.

## Todo
I still need to add doc comments to `Extract`.

---

## Changelog

### Changed
- The `Extract` `RenderStage` now runs on the render world (instead of the main world as before).
   You must use the `Extract` `SystemParam` to access the main world during the extract phase.
   Resources on the render world can now be accessed using `ResMut` during extract.

### Removed
- `Commands::spawn_and_forget`. Use `Commands::get_or_spawn(e).insert_bundle(bundle)` instead

## Migration Guide

The `Extract` `RenderStage` now runs on the render world (instead of the main world as before).
You must use the `Extract` `SystemParam` to access the main world during the extract phase. `Extract` takes a single type parameter, which is any system parameter (such as `Res`, `Query` etc.). It will extract this from the main world, and returns the result of this extraction when `value` is called on it.

For example, if previously your extract system looked like:
```rust
fn extract_clouds(mut commands: Commands, clouds: Query<Entity, With<Cloud>>) {
    for cloud in clouds.iter() {
        commands.get_or_spawn(cloud).insert(Cloud);
    }
}
```
the new version would be:
```rust
fn extract_clouds(mut commands: Commands, mut clouds: Extract<Query<Entity, With<Cloud>>>) {
    for cloud in clouds.value().iter() {
        commands.get_or_spawn(cloud).insert(Cloud);
    }
}
```
The diff is:
```diff
--- a/src/clouds.rs
+++ b/src/clouds.rs
@@ -1,5 +1,5 @@
-fn extract_clouds(mut commands: Commands, clouds: Query<Entity, With<Cloud>>) {
-    for cloud in clouds.iter() {
+fn extract_clouds(mut commands: Commands, mut clouds: Extract<Query<Entity, With<Cloud>>>) {
+    for cloud in clouds.value().iter() {
         commands.get_or_spawn(cloud).insert(Cloud);
     }
 }
```
You can now also access resources from the render world using the normal system parameters during `Extract`:
```rust
fn extract_assets(mut render_assets: ResMut<MyAssets>, source_assets: Extract<Res<MyAssets>>) {
     *render_assets = source_assets.clone();
}
```
Please note that all existing extract systems need to be updated to match this new style; even if they currently compile they will not run as expected. A warning will be emitted on a best-effort basis if this is not met.

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-07-08 23:56:33 +00:00
Robin KAY
5b5013d540 Add ViewRangefinder3d to reduce boilerplate when enqueuing standard 3D PhaseItems. (#5014)
# Objective

Reduce the boilerplate code needed to make draw order sorting work correctly when queuing items through new common functionality. Also fix several instances in the bevy code-base (mostly examples) where this boilerplate appears to be incorrect.

## Solution

- Moved the logic for handling back-to-front vs front-to-back draw ordering into the PhaseItems by inverting the sort key ordering of Opaque3d and AlphaMask3d. The means that all the standard 3d rendering phases measure distance in the same way. Clients of these structs no longer need to know to negate the distance.
- Added a new utility struct, ViewRangefinder3d, which encapsulates the maths needed to calculate a "distance" from an ExtractedView and a mesh's transform matrix.
- Converted all the occurrences of the distance calculations in Bevy and its examples to use ViewRangefinder3d. Several of these occurrences appear to be buggy because they don't invert the view matrix or don't negate the distance where appropriate. This leads me to the view that Bevy should expose a facility to correctly perform this calculation.

## Migration Guide

Code which creates Opaque3d, AlphaMask3d, or Transparent3d phase items _should_ use ViewRangefinder3d to calculate the distance value.

Code which manually calculated the distance for Opaque3d or AlphaMask3d phase items and correctly negated the z value will no longer depth sort correctly. However, incorrect depth sorting for these types will not impact the rendered output as sorting is only a performance optimisation when drawing with depth-testing enabled. Code which manually calculated the distance for Transparent3d phase items will continue to work as before.
2022-07-05 06:13:39 +00:00
Carter Anderson
747b0c69b0 Better Materials: AsBindGroup trait and derive, simpler Material trait (#5053)
# Objective

This PR reworks Bevy's Material system, making the user experience of defining Materials _much_ nicer. Bevy's previous material system leaves a lot to be desired:
* Materials require manually implementing the `RenderAsset` trait, which involves manually generating the bind group, handling gpu buffer data transfer, looking up image textures, etc. Even the simplest single-texture material involves writing ~80 unnecessary lines of code. This was never the long term plan.
* There are two material traits, which is confusing, hard to document, and often redundant: `Material` and `SpecializedMaterial`. `Material` implicitly implements `SpecializedMaterial`, and `SpecializedMaterial` is used in most high level apis to support both use cases. Most users shouldn't need to think about specialization at all (I consider it a "power-user tool"), so the fact that `SpecializedMaterial` is front-and-center in our apis is a miss.
* Implementing either material trait involves a lot of "type soup". The "prepared asset" parameter is particularly heinous: `&<Self as RenderAsset>::PreparedAsset`. Defining vertex and fragment shaders is also more verbose than it needs to be. 

## Solution

Say hello to the new `Material` system:

```rust
#[derive(AsBindGroup, TypeUuid, Debug, Clone)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
pub struct CoolMaterial {
    #[uniform(0)]
    color: Color,
    #[texture(1)]
    #[sampler(2)]
    color_texture: Handle<Image>,
}
impl Material for CoolMaterial {
    fn fragment_shader() -> ShaderRef {
        "cool_material.wgsl".into()
    }
}
```

Thats it! This same material would have required [~80 lines of complicated "type heavy" code](https://github.com/bevyengine/bevy/blob/v0.7.0/examples/shader/shader_material.rs) in the old Material system. Now it is just 14 lines of simple, readable code.

This is thanks to a new consolidated `Material` trait and the new `AsBindGroup` trait / derive.

### The new `Material` trait

The old "split" `Material` and `SpecializedMaterial` traits have been removed in favor of a new consolidated `Material` trait. All of the functions on the trait are optional.

The difficulty of implementing `Material` has been reduced by simplifying dataflow and removing type complexity:

```rust
// Old
impl Material for CustomMaterial {
    fn fragment_shader(asset_server: &AssetServer) -> Option<Handle<Shader>> {
        Some(asset_server.load("custom_material.wgsl"))
    }

    fn alpha_mode(render_asset: &<Self as RenderAsset>::PreparedAsset) -> AlphaMode {
        render_asset.alpha_mode
    }
}

// New
impl Material for CustomMaterial {
    fn fragment_shader() -> ShaderRef {
        "custom_material.wgsl".into()
    }

    fn alpha_mode(&self) -> AlphaMode {
        self.alpha_mode
    }
}
```

Specialization is still supported, but it is hidden by default under the `specialize()` function (more on this later).

### The `AsBindGroup` trait / derive

The `Material` trait now requires the `AsBindGroup` derive. This can be implemented manually relatively easily, but deriving it will almost always be preferable. 

Field attributes like `uniform` and `texture` are used to define which fields should be bindings,
what their binding type is, and what index they should be bound at:

```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
    #[uniform(0)]
    color: Color,
    #[texture(1)]
    #[sampler(2)]
    color_texture: Handle<Image>,
}
```

In WGSL shaders, the binding looks like this:

```wgsl
struct CoolMaterial {
    color: vec4<f32>;
};

[[group(1), binding(0)]]
var<uniform> material: CoolMaterial;
[[group(1), binding(1)]]
var color_texture: texture_2d<f32>;
[[group(1), binding(2)]]
var color_sampler: sampler;
```

Note that the "group" index is determined by the usage context. It is not defined in `AsBindGroup`. Bevy material bind groups are bound to group 1.

The following field-level attributes are supported:
* `uniform(BINDING_INDEX)`
    * The field will be converted to a shader-compatible type using the `ShaderType` trait, written to a `Buffer`, and bound as a uniform. It can also be derived for custom structs.
* `texture(BINDING_INDEX)`
    * This field's `Handle<Image>` will be used to look up the matching `Texture` gpu resource, which will be bound as a texture in shaders. The field will be assumed to implement `Into<Option<Handle<Image>>>`. In practice, most fields should be a `Handle<Image>` or `Option<Handle<Image>>`. If the value of an `Option<Handle<Image>>` is `None`, the new `FallbackImage` resource will be used instead. This attribute can be used in conjunction with a `sampler` binding attribute (with a different binding index).
* `sampler(BINDING_INDEX)`
    * Behaves exactly like the `texture` attribute, but sets the Image's sampler binding instead of the texture. 

Note that fields without field-level binding attributes will be ignored.
```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
    #[uniform(0)]
    color: Color,
    this_field_is_ignored: String,
}
```

As mentioned above, `Option<Handle<Image>>` is also supported:
```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
    #[uniform(0)]
    color: Color,
    #[texture(1)]
    #[sampler(2)]
    color_texture: Option<Handle<Image>>,
}
```
This is useful if you want a texture to be optional. When the value is `None`, the `FallbackImage` will be used for the binding instead, which defaults to "pure white".

Field uniforms with the same binding index will be combined into a single binding:
```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
    #[uniform(0)]
    color: Color,
    #[uniform(0)]
    roughness: f32,
}
```

In WGSL shaders, the binding would look like this:
```wgsl
struct CoolMaterial {
    color: vec4<f32>;
    roughness: f32;
};

[[group(1), binding(0)]]
var<uniform> material: CoolMaterial;
```

Some less common scenarios will require "struct-level" attributes. These are the currently supported struct-level attributes:
* `uniform(BINDING_INDEX, ConvertedShaderType)`
    * Similar to the field-level `uniform` attribute, but instead the entire `AsBindGroup` value is converted to `ConvertedShaderType`, which must implement `ShaderType`. This is useful if more complicated conversion logic is required.
* `bind_group_data(DataType)`
    * The `AsBindGroup` type will be converted to some `DataType` using `Into<DataType>` and stored as `AsBindGroup::Data` as part of the `AsBindGroup::as_bind_group` call. This is useful if data needs to be stored alongside the generated bind group, such as a unique identifier for a material's bind group. The most common use case for this attribute is "shader pipeline specialization".

The previous `CoolMaterial` example illustrating "combining multiple field-level uniform attributes with the same binding index" can
also be equivalently represented with a single struct-level uniform attribute:
```rust
#[derive(AsBindGroup)]
#[uniform(0, CoolMaterialUniform)]
struct CoolMaterial {
    color: Color,
    roughness: f32,
}

#[derive(ShaderType)]
struct CoolMaterialUniform {
    color: Color,
    roughness: f32,
}

impl From<&CoolMaterial> for CoolMaterialUniform {
    fn from(material: &CoolMaterial) -> CoolMaterialUniform {
        CoolMaterialUniform {
            color: material.color,
            roughness: material.roughness,
        }
    }
}
```

### Material Specialization

Material shader specialization is now _much_ simpler:

```rust
#[derive(AsBindGroup, TypeUuid, Debug, Clone)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
#[bind_group_data(CoolMaterialKey)]
struct CoolMaterial {
    #[uniform(0)]
    color: Color,
    is_red: bool,
}

#[derive(Copy, Clone, Hash, Eq, PartialEq)]
struct CoolMaterialKey {
    is_red: bool,
}

impl From<&CoolMaterial> for CoolMaterialKey {
    fn from(material: &CoolMaterial) -> CoolMaterialKey {
        CoolMaterialKey {
            is_red: material.is_red,
        }
    }
}

impl Material for CoolMaterial {
    fn fragment_shader() -> ShaderRef {
        "cool_material.wgsl".into()
    }

    fn specialize(
        pipeline: &MaterialPipeline<Self>,
        descriptor: &mut RenderPipelineDescriptor,
        layout: &MeshVertexBufferLayout,
        key: MaterialPipelineKey<Self>,
    ) -> Result<(), SpecializedMeshPipelineError> {
        if key.bind_group_data.is_red {
            let fragment = descriptor.fragment.as_mut().unwrap();
            fragment.shader_defs.push("IS_RED".to_string());
        }
        Ok(())
    }
}
```

Setting `bind_group_data` is not required for specialization (it defaults to `()`). Scenarios like "custom vertex attributes" also benefit from this system:
```rust
impl Material for CustomMaterial {
    fn vertex_shader() -> ShaderRef {
        "custom_material.wgsl".into()
    }

    fn fragment_shader() -> ShaderRef {
        "custom_material.wgsl".into()
    }

    fn specialize(
        pipeline: &MaterialPipeline<Self>,
        descriptor: &mut RenderPipelineDescriptor,
        layout: &MeshVertexBufferLayout,
        key: MaterialPipelineKey<Self>,
    ) -> Result<(), SpecializedMeshPipelineError> {
        let vertex_layout = layout.get_layout(&[
            Mesh::ATTRIBUTE_POSITION.at_shader_location(0),
            ATTRIBUTE_BLEND_COLOR.at_shader_location(1),
        ])?;
        descriptor.vertex.buffers = vec![vertex_layout];
        Ok(())
    }
}
```

### Ported `StandardMaterial` to the new `Material` system

Bevy's built-in PBR material uses the new Material system (including the AsBindGroup derive):

```rust
#[derive(AsBindGroup, Debug, Clone, TypeUuid)]
#[uuid = "7494888b-c082-457b-aacf-517228cc0c22"]
#[bind_group_data(StandardMaterialKey)]
#[uniform(0, StandardMaterialUniform)]
pub struct StandardMaterial {
    pub base_color: Color,
    #[texture(1)]
    #[sampler(2)]
    pub base_color_texture: Option<Handle<Image>>,
    /* other fields omitted for brevity */
```

### Ported Bevy examples to the new `Material` system

The overall complexity of Bevy's "custom shader examples" has gone down significantly. Take a look at the diffs if you want a dopamine spike.

Please note that while this PR has a net increase in "lines of code", most of those extra lines come from added documentation. There is a significant reduction
in the overall complexity of the code (even accounting for the new derive logic).

---

## Changelog

### Added

* `AsBindGroup` trait and derive, which make it much easier to transfer data to the gpu and generate bind groups for a given type.

### Changed

* The old `Material` and `SpecializedMaterial` traits have been replaced by a consolidated (much simpler) `Material` trait. Materials no longer implement `RenderAsset`.
* `StandardMaterial` was ported to the new material system. There are no user-facing api changes to the `StandardMaterial` struct api, but it now implements `AsBindGroup` and `Material` instead of `RenderAsset` and `SpecializedMaterial`.

## Migration Guide
The Material system has been reworked to be much simpler. We've removed a lot of boilerplate with the new `AsBindGroup` derive and the `Material` trait is simpler as well!

### Bevy 0.7 (old)

```rust
#[derive(Debug, Clone, TypeUuid)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
pub struct CustomMaterial {
    color: Color,
    color_texture: Handle<Image>,
}

#[derive(Clone)]
pub struct GpuCustomMaterial {
    _buffer: Buffer,
    bind_group: BindGroup,
}

impl RenderAsset for CustomMaterial {
    type ExtractedAsset = CustomMaterial;
    type PreparedAsset = GpuCustomMaterial;
    type Param = (SRes<RenderDevice>, SRes<MaterialPipeline<Self>>);
    fn extract_asset(&self) -> Self::ExtractedAsset {
        self.clone()
    }

    fn prepare_asset(
        extracted_asset: Self::ExtractedAsset,
        (render_device, material_pipeline): &mut SystemParamItem<Self::Param>,
    ) -> Result<Self::PreparedAsset, PrepareAssetError<Self::ExtractedAsset>> {
        let color = Vec4::from_slice(&extracted_asset.color.as_linear_rgba_f32());

        let byte_buffer = [0u8; Vec4::SIZE.get() as usize];
        let mut buffer = encase::UniformBuffer::new(byte_buffer);
        buffer.write(&color).unwrap();

        let buffer = render_device.create_buffer_with_data(&BufferInitDescriptor {
            contents: buffer.as_ref(),
            label: None,
            usage: BufferUsages::UNIFORM | BufferUsages::COPY_DST,
        });

        let (texture_view, texture_sampler) = if let Some(result) = material_pipeline
            .mesh_pipeline
            .get_image_texture(gpu_images, &Some(extracted_asset.color_texture.clone()))
        {
            result
        } else {
            return Err(PrepareAssetError::RetryNextUpdate(extracted_asset));
        };
        let bind_group = render_device.create_bind_group(&BindGroupDescriptor {
            entries: &[
                BindGroupEntry {
                    binding: 0,
                    resource: buffer.as_entire_binding(),
                },
                BindGroupEntry {
                    binding: 0,
                    resource: BindingResource::TextureView(texture_view),
                },
                BindGroupEntry {
                    binding: 1,
                    resource: BindingResource::Sampler(texture_sampler),
                },
            ],
            label: None,
            layout: &material_pipeline.material_layout,
        });

        Ok(GpuCustomMaterial {
            _buffer: buffer,
            bind_group,
        })
    }
}

impl Material for CustomMaterial {
    fn fragment_shader(asset_server: &AssetServer) -> Option<Handle<Shader>> {
        Some(asset_server.load("custom_material.wgsl"))
    }

    fn bind_group(render_asset: &<Self as RenderAsset>::PreparedAsset) -> &BindGroup {
        &render_asset.bind_group
    }

    fn bind_group_layout(render_device: &RenderDevice) -> BindGroupLayout {
        render_device.create_bind_group_layout(&BindGroupLayoutDescriptor {
            entries: &[
                BindGroupLayoutEntry {
                    binding: 0,
                    visibility: ShaderStages::FRAGMENT,
                    ty: BindingType::Buffer {
                        ty: BufferBindingType::Uniform,
                        has_dynamic_offset: false,
                        min_binding_size: Some(Vec4::min_size()),
                    },
                    count: None,
                },
                BindGroupLayoutEntry {
                    binding: 1,
                    visibility: ShaderStages::FRAGMENT,
                    ty: BindingType::Texture {
                        multisampled: false,
                        sample_type: TextureSampleType::Float { filterable: true },
                        view_dimension: TextureViewDimension::D2Array,
                    },
                    count: None,
                },
                BindGroupLayoutEntry {
                    binding: 2,
                    visibility: ShaderStages::FRAGMENT,
                    ty: BindingType::Sampler(SamplerBindingType::Filtering),
                    count: None,
                },
            ],
            label: None,
        })
    }
}
```

### Bevy 0.8 (new)

```rust
impl Material for CustomMaterial {
    fn fragment_shader() -> ShaderRef {
        "custom_material.wgsl".into()
    }
}

#[derive(AsBindGroup, TypeUuid, Debug, Clone)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
pub struct CustomMaterial {
    #[uniform(0)]
    color: Color,
    #[texture(1)]
    #[sampler(2)]
    color_texture: Handle<Image>,
}
```

## Future Work

* Add support for more binding types (cubemaps, buffers, etc). This PR intentionally includes a bare minimum number of binding types to keep "reviewability" in check.
* Consider optionally eliding binding indices using binding names. `AsBindGroup` could pass in (optional?) reflection info as a "hint".
    * This would make it possible for the derive to do this:
        ```rust
        #[derive(AsBindGroup)]
        pub struct CustomMaterial {
            #[uniform]
            color: Color,
            #[texture]
            #[sampler]
            color_texture: Option<Handle<Image>>,
            alpha_mode: AlphaMode,
        }
        ```
    * Or this
        ```rust
        #[derive(AsBindGroup)]
        pub struct CustomMaterial {
            #[binding]
            color: Color,
            #[binding]
            color_texture: Option<Handle<Image>>,
            alpha_mode: AlphaMode,
        }
        ```
    * Or even this (if we flip to "include bindings by default")
        ```rust
        #[derive(AsBindGroup)]
        pub struct CustomMaterial {
            color: Color,
            color_texture: Option<Handle<Image>>,
            #[binding(ignore)]
            alpha_mode: AlphaMode,
        }
        ```
* If we add the option to define custom draw functions for materials (which could be done in a type-erased way), I think that would be enough to support extra non-material bindings. Worth considering!
2022-06-30 23:48:46 +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
robtfm
ee4bcbea3c add depth_bias to SpecializedMaterial (#4101)
# Objective

allow meshes with equal z-depth to be rendered in a chosen order / avoid z-fighting

## Solution

add a depth_bias to SpecializedMaterial that is added to the mesh depth used for render-ordering.
2022-05-31 02:02:49 +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
Robert Swain
479f43bbf3 Filter material handles on extraction (#4178)
# Objective

- While optimising many_cubes, I noticed that all material handles are extracted regardless of whether the entity to which the handle belongs is visible or not. As such >100k handles are extracted when only <20k are visible.

## Solution

- Only extract material handles of visible entities.
- This improves `many_cubes -- sphere` from ~42fps to ~48fps. It reduces not only the extraction time but also system commands time. `Handle<StandardMaterial>` extraction and its system commands went from 0.522ms + 3.710ms respectively, to 0.267ms + 0.227ms an 88% reduction for this system for this case. It's very view dependent but...
2022-05-03 18:28:04 +00:00