This commit implements the [depth of field] effect, simulating the blur
of objects out of focus of the virtual lens. Either the [hexagonal
bokeh] effect or a faster Gaussian blur may be used. In both cases, the
implementation is a simple separable two-pass convolution. This is not
the most physically-accurate real-time bokeh technique that exists;
Unreal Engine has [a more accurate implementation] of "cinematic depth
of field" from 2018. However, it's simple, and most engines provide
something similar as a fast option, often called "mobile" depth of
field.
The general approach is outlined in [a blog post from 2017]. We take
advantage of the fact that both Gaussian blurs and hexagonal bokeh blurs
are *separable*. This means that their 2D kernels can be reduced to a
small number of 1D kernels applied one after another, asymptotically
reducing the amount of work that has to be done. Gaussian blurs can be
accomplished by blurring horizontally and then vertically, while
hexagonal bokeh blurs can be done with a vertical blur plus a diagonal
blur, plus two diagonal blurs. In both cases, only two passes are
needed. Bokeh requires the first pass to have a second render target and
requires two subpasses in the second pass, which decreases its
performance relative to the Gaussian blur.
The bokeh blur is generally more aesthetically pleasing than the
Gaussian blur, as it simulates the effect of a camera more accurately.
The shape of the bokeh circles are determined by the number of blades of
the aperture. In our case, we use a hexagon, which is usually considered
specific to lower-quality cameras. (This is a downside of the fast
hexagon approach compared to the higher-quality approaches.) The blur
amount is generally specified by the [f-number], which we use to compute
the focal length from the film size and FOV. By default, we simulate
standard cinematic cameras of f/1 and [Super 35]. The developer can
customize these values as desired.
A new example has been added to demonstrate depth of field. It allows
customization of the mode (Gaussian vs. bokeh), focal distance and
f-numbers. The test scene is inspired by a [blog post on depth of field
in Unity]; however, the effect is implemented in a completely different
way from that blog post, and all the assets (textures, etc.) are
original.
Bokeh depth of field:
Gaussian depth of field:
No depth of field:
[depth of field]: https://en.wikipedia.org/wiki/Depth_of_field
[hexagonal bokeh]:
https://colinbarrebrisebois.com/2017/04/18/hexagonal-bokeh-blur-revisited/
[a more accurate implementation]:
https://epicgames.ent.box.com/s/s86j70iamxvsuu6j35pilypficznec04
[a blog post from 2017]:
https://colinbarrebrisebois.com/2017/04/18/hexagonal-bokeh-blur-revisited/
[f-number]: https://en.wikipedia.org/wiki/F-number
[Super 35]: https://en.wikipedia.org/wiki/Super_35
[blog post on depth of field in Unity]:
https://catlikecoding.com/unity/tutorials/advanced-rendering/depth-of-field/
## Changelog
### Added
* A depth of field postprocessing effect is now available, to simulate
objects being out of focus of the camera. To use it, add
`DepthOfFieldSettings` to an entity containing a `Camera3d` component.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Bram Buurlage <brambuurlage@gmail.com>
Clearcoat is a separate material layer that represents a thin
translucent layer of a material. Examples include (from the [Filament
spec]) car paint, soda cans, and lacquered wood. This commit implements
support for clearcoat following the Filament and Khronos specifications,
marking the beginnings of support for multiple PBR layers in Bevy.
The [`KHR_materials_clearcoat`] specification describes the clearcoat
support in glTF. In Blender, applying a clearcoat to the Principled BSDF
node causes the clearcoat settings to be exported via this extension. As
of this commit, Bevy parses and reads the extension data when present in
glTF. Note that the `gltf` crate has no support for
`KHR_materials_clearcoat`; this patch therefore implements the JSON
semantics manually.
Clearcoat is integrated with `StandardMaterial`, but the code is behind
a series of `#ifdef`s that only activate when clearcoat is present.
Additionally, the `pbr_feature_layer_material_textures` Cargo feature
must be active in order to enable support for clearcoat factor maps,
clearcoat roughness maps, and clearcoat normal maps. This approach
mirrors the same pattern used by the existing transmission feature and
exists to avoid running out of texture bindings on platforms like WebGL
and WebGPU. Note that constant clearcoat factors and roughness values
*are* supported in the browser; only the relatively-less-common maps are
disabled on those platforms.
This patch refactors the lighting code in `StandardMaterial`
significantly in order to better support multiple layers in a natural
way. That code was due for a refactor in any case, so this is a nice
improvement.
A new demo, `clearcoat`, has been added. It's based on [the
corresponding three.js demo], but all the assets (aside from the skybox
and environment map) are my original work.
[Filament spec]:
https://google.github.io/filament/Filament.html#materialsystem/clearcoatmodel
[`KHR_materials_clearcoat`]:
https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Khronos/KHR_materials_clearcoat/README.md
[the corresponding three.js demo]:
https://threejs.org/examples/webgl_materials_physical_clearcoat.html
## Changelog
### Added
* `StandardMaterial` now supports a clearcoat layer, which represents a
thin translucent layer over an underlying material.
* The glTF loader now supports the `KHR_materials_clearcoat` extension,
representing materials with clearcoat layers.
## Migration Guide
* The lighting functions in the `pbr_lighting` WGSL module now have
clearcoat parameters, if `STANDARD_MATERIAL_CLEARCOAT` is defined.
* The `R` reflection vector parameter has been removed from some
lighting functions, as it was unused.
# Objective
`bevy_pbr/utils.wgsl` shader file contains mathematical constants and
color conversion functions. Both of those should be accessible without
enabling `bevy_pbr` feature. For example, tonemapping can be done in non
pbr scenario, and it uses color conversion functions.
Fixes#13207
## Solution
* Move mathematical constants (such as PI, E) from
`bevy_pbr/src/render/utils.wgsl` into `bevy_render/src/maths.wgsl`
* Move color conversion functions from `bevy_pbr/src/render/utils.wgsl`
into new file `bevy_render/src/color_operations.wgsl`
## Testing
Ran multiple examples, checked they are working:
* tonemapping
* color_grading
* 3d_scene
* animated_material
* deferred_rendering
* 3d_shapes
* fog
* irradiance_volumes
* meshlet
* parallax_mapping
* pbr
* reflection_probes
* shadow_biases
* 2d_gizmos
* light_gizmos
---
## Changelog
* Moved mathematical constants (such as PI, E) from
`bevy_pbr/src/render/utils.wgsl` into `bevy_render/src/maths.wgsl`
* Moved color conversion functions from `bevy_pbr/src/render/utils.wgsl`
into new file `bevy_render/src/color_operations.wgsl`
## Migration Guide
In user's shader code replace usage of mathematical constants from
`bevy_pbr::utils` to the usage of the same constants from
`bevy_render::maths`.
# Objective
- Add auto exposure/eye adaptation to the bevy render pipeline.
- Support features that users might expect from other engines:
- Metering masks
- Compensation curves
- Smooth exposure transitions
This PR is based on an implementation I already built for a personal
project before https://github.com/bevyengine/bevy/pull/8809 was
submitted, so I wasn't able to adopt that PR in the proper way. I've
still drawn inspiration from it, so @fintelia should be credited as
well.
## Solution
An auto exposure compute shader builds a 64 bin histogram of the scene's
luminance, and then adjusts the exposure based on that histogram. Using
a histogram allows the system to ignore outliers like shadows and
specular highlights, and it allows to give more weight to certain areas
based on a mask.
---
## Changelog
- Added: AutoExposure plugin that allows to adjust a camera's exposure
based on it's scene's luminance.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Implement visibility ranges, also known as hierarchical levels of detail
(HLODs).
This commit introduces a new component, `VisibilityRange`, which allows
developers to specify camera distances in which meshes are to be shown
and hidden. Hiding meshes happens early in the rendering pipeline, so
this feature can be used for level of detail optimization. Additionally,
this feature is properly evaluated per-view, so different views can show
different levels of detail.
This feature differs from proper mesh LODs, which can be implemented
later. Engines generally implement true mesh LODs later in the pipeline;
they're typically more efficient than HLODs with GPU-driven rendering.
However, mesh LODs are more limited than HLODs, because they require the
lower levels of detail to be meshes with the same vertex layout and
shader (and perhaps the same material) as the original mesh. Games often
want to use objects other than meshes to replace distant models, such as
*octahedral imposters* or *billboard imposters*.
The reason why the feature is called *hierarchical level of detail* is
that HLODs can replace multiple meshes with a single mesh when the
camera is far away. This can be useful for reducing drawcall count. Note
that `VisibilityRange` doesn't automatically propagate down to children;
it must be placed on every mesh.
Crossfading between different levels of detail is supported, using the
standard 4x4 ordered dithering pattern from [1]. The shader code to
compute the dithering patterns should be well-optimized. The dithering
code is only active when visibility ranges are in use for the mesh in
question, so that we don't lose early Z.
Cascaded shadow maps show the HLOD level of the view they're associated
with. Point light and spot light shadow maps, which have no CSMs,
display all HLOD levels that are visible in any view. To support this
efficiently and avoid doing visibility checks multiple times, we
precalculate all visible HLOD levels for each entity with a
`VisibilityRange` during the `check_visibility_range` system.
A new example, `visibility_range`, has been added to the tree, as well
as a new low-poly version of the flight helmet model to go with it. It
demonstrates use of the visibility range feature to provide levels of
detail.
[1]: https://en.wikipedia.org/wiki/Ordered_dithering#Threshold_map
[^1]: Unreal doesn't have a feature that exactly corresponds to
visibility ranges, but Unreal's HLOD system serves roughly the same
purpose.
## Changelog
### Added
* A new `VisibilityRange` component is available to conditionally enable
entity visibility at camera distances, with optional crossfade support.
This can be used to implement different levels of detail (LODs).
## Screenshots
High-poly model:
Low-poly model up close:
Crossfading between the two:
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
This commit expands Bevy's existing tonemapping feature to a complete
set of filmic color grading tools, matching those of engines like Unity,
Unreal, and Godot. The following features are supported:
* White point adjustment. This is inspired by Unity's implementation of
the feature, but simplified and optimized. *Temperature* and *tint*
control the adjustments to the *x* and *y* chromaticity values of [CIE
1931]. Following Unity, the adjustments are made relative to the [D65
standard illuminant] in the [LMS color space].
* Hue rotation. This simply converts the RGB value to [HSV], alters the
hue, and converts back.
* Color correction. This allows the *gamma*, *gain*, and *lift* values
to be adjusted according to the standard [ASC CDL combined function].
* Separate color correction for shadows, midtones, and highlights.
Blender's source code was used as a reference for the implementation of
this. The midtone ranges can be adjusted by the user. To avoid abrupt
color changes, a small crossfade is used between the different sections
of the image, again following Blender's formulas.
A new example, `color_grading`, has been added, offering a GUI to change
all the color grading settings. It uses the same test scene as the
existing `tonemapping` example, which has been factored out into a
shared glTF scene.
[CIE 1931]: https://en.wikipedia.org/wiki/CIE_1931_color_space
[D65 standard illuminant]:
https://en.wikipedia.org/wiki/Standard_illuminant#Illuminant_series_D
[LMS color space]: https://en.wikipedia.org/wiki/LMS_color_space
[HSV]: https://en.wikipedia.org/wiki/HSL_and_HSV
[ASC CDL combined function]:
https://en.wikipedia.org/wiki/ASC_CDL#Combined_Function
## Changelog
### Added
* Many new filmic color grading options have been added to the
`ColorGrading` component.
## Migration Guide
* `ColorGrading::gamma` and `ColorGrading::pre_saturation` are now set
separately for the `shadows`, `midtones`, and `highlights` sections. You
can migrate code with the `ColorGrading::all_sections` and
`ColorGrading::all_sections_mut` functions, which access and/or update
all sections at once.
* `ColorGrading::post_saturation` and `ColorGrading::exposure` are now
fields of `ColorGrading::global`.
## Screenshots
# Objective
- Example `compute_shader_game_of_life` is random and not following the
rules of the game of life: at each steps, it randomly reads some pixel
of the current step and some of the previous step instead of only from
the previous step
- Fixes#9353
## Solution
- Adopted from #9678
- Added a switch of the texture displayed every frame otherwise the game
of life looks wrong
- Added a way to display the texture bigger so that I could manually
check everything was right
---------
Co-authored-by: Sludge <96552222+SludgePhD@users.noreply.github.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
# Objective
- It's pretty common for users to want to read data back from the gpu
and into the main world
## Solution
- Add a simple example that shows how to read data back from the gpu and
send it to the main world using a channel.
- The example is largely based on this wgpu example but adapted to bevy
-
fb305b85f6/examples/src/repeated_compute/mod.rs
---------
Co-authored-by: stormy <120167078+stowmyy@users.noreply.github.com>
Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
Created soundtrack example, fade-in and fade-out features, added new
assets, and updated credits.
# Objective
- Fixes#12651
## Solution
- Created a resource to hold the track list.
- The audio assets are then loaded by the asset server and added to the
track list.
- Once the game is in a specific state, an `AudioBundle` is spawned and
plays the appropriate track.
- The audio volume starts at zero and is then incremented gradually
until it reaches full volume.
- Once the game state changes, the current track fades out, and a new
one fades in at the same time, offering a relatively seamless
transition.
- Once a track is completely faded out, it is despawned from the app.
- Game state changes are simulated through a `Timer` for simplicity.
- Track change system is only run if there is a change in the
`GameState` resource.
- All tracks are used according to their respective licenses.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
This is an implementation of RFC #51:
https://github.com/bevyengine/rfcs/blob/main/rfcs/51-animation-composition.md
Note that the implementation strategy is different from the one outlined
in that RFC, because two-phase animation has now landed.
# Objective
Bevy needs animation blending. The RFC for this is [RFC 51].
## Solution
This is an implementation of the RFC. Note that the implementation
strategy is different from the one outlined there, because two-phase
animation has now landed.
This is just a draft to get the conversation started. Currently we're
missing a few things:
- [x] A fully-fleshed-out mechanism for transitions
- [x] A serialization format for `AnimationGraph`s
- [x] Examples are broken, other than `animated_fox`
- [x] Documentation
---
## Changelog
### Added
* The `AnimationPlayer` has been reworked to support blending multiple
animations together through an `AnimationGraph`, and as such will no
longer function unless a `Handle<AnimationGraph>` has been added to the
entity containing the player. See [RFC 51] for more details.
* Transition functionality has moved from the `AnimationPlayer` to a new
component, `AnimationTransitions`, which works in tandem with the
`AnimationGraph`.
## Migration Guide
* `AnimationPlayer`s can no longer play animations by themselves and
need to be paired with a `Handle<AnimationGraph>`. Code that was using
`AnimationPlayer` to play animations will need to create an
`AnimationGraph` asset first, add a node for the clip (or clips) you
want to play, and then supply the index of that node to the
`AnimationPlayer`'s `play` method.
* The `AnimationPlayer::play_with_transition()` method has been removed
and replaced with the `AnimationTransitions` component. If you were
previously using `AnimationPlayer::play_with_transition()`, add all
animations that you were playing to the `AnimationGraph`, and create an
`AnimationTransitions` component to manage the blending between them.
[RFC 51]:
https://github.com/bevyengine/rfcs/blob/main/rfcs/51-animation-composition.md
---------
Co-authored-by: Rob Parrett <robparrett@gmail.com>
# Objective
Follow up to #11600 and #10588https://github.com/bevyengine/bevy/issues/11944 made clear that some
people want to use slicing with texture atlases
## Changelog
* Added support for `TextureAtlas` slicing and tiling.
`SpriteSheetBundle` and `AtlasImageBundle` can now use `ImageScaleMode`
* Added new `ui_texture_atlas_slice` example using a texture sheet
<img width="798" alt="Screenshot 2024-02-23 at 11 58 35"
src="https://github.com/bevyengine/bevy/assets/26703856/47a8b764-127c-4a06-893f-181703777501">
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Pablo Reinhardt <126117294+pablo-lua@users.noreply.github.com>
# Objective
- Fixes#9670
- Avoid a crash in CI due to
```
thread 'Compute Task Pool (0)' panicked at /Users/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wgpu-0.19.1/src/backend/wgpu_core.rs:3009:5:
wgpu error: Validation Error
Caused by:
In Device::create_bind_group
The adapter does not support read access for storages texture of format Rgba8Unorm
```
## Solution
- Use an `R32Float` texture instead of an `Rgba8Unorm` as it's a tier 1
texture format https://github.com/gpuweb/gpuweb/issues/3838 and is more
supported
- This should also improve support for webgpu in the next wgpu version
> Follow up to #10588
> Closes#11749 (Supersedes #11756)
Enable Texture slicing for the following UI nodes:
- `ImageBundle`
- `ButtonBundle`
<img width="739" alt="Screenshot 2024-01-29 at 13 57 43"
src="https://github.com/bevyengine/bevy/assets/26703856/37675681-74eb-4689-ab42-024310cf3134">
I also added a collection of `fantazy-ui-borders` from
[Kenney's](www.kenney.nl) assets, with the appropriate license (CC).
If it's a problem I can use the same textures as the `sprite_slice`
example
# Work done
Added the `ImageScaleMode` component to the targetted bundles, most of
the logic is directly reused from `bevy_sprite`.
The only additional internal component is the UI specific
`ComputedSlices`, which does the same thing as its spritee equivalent
but adapted to UI code.
Again the slicing is not compatible with `TextureAtlas`, it's something
I need to tackle more deeply in the future
# Fixes
* [x] I noticed that `TextureSlicer::compute_slices` could infinitely
loop if the border was larger that the image half extents, now an error
is triggered and the texture will fallback to being stretched
* [x] I noticed that when using small textures with very small *tiling*
options we could generate hundred of thousands of slices. Now I set a
minimum size of 1 pixel per slice, which is already ridiculously small,
and a warning will be sent at runtime when slice count goes above 1000
* [x] Sprite slicing with `flip_x` or `flip_y` would give incorrect
results, correct flipping is now supported to both sprites and ui image
nodes thanks to @odecay observation
# GPU Alternative
I create a separate branch attempting to implementing 9 slicing and
tiling directly through the `ui.wgsl` fragment shader. It works but
requires sending more data to the GPU:
- slice border
- tiling factors
And more importantly, the actual quad *scale* which is hard to put in
the shader with the current code, so that would be for a later iteration
# Objective
Bevy could benefit from *irradiance volumes*, also known as *voxel
global illumination* or simply as light probes (though this term is not
preferred, as multiple techniques can be called light probes).
Irradiance volumes are a form of baked global illumination; they work by
sampling the light at the centers of each voxel within a cuboid. At
runtime, the voxels surrounding the fragment center are sampled and
interpolated to produce indirect diffuse illumination.
## Solution
This is divided into two sections. The first is copied and pasted from
the irradiance volume module documentation and describes the technique.
The second part consists of notes on the implementation.
### Overview
An *irradiance volume* is a cuboid voxel region consisting of
regularly-spaced precomputed samples of diffuse indirect light. They're
ideal if you have a dynamic object such as a character that can move
about
static non-moving geometry such as a level in a game, and you want that
dynamic object to be affected by the light bouncing off that static
geometry.
To use irradiance volumes, you need to precompute, or *bake*, the
indirect
light in your scene. Bevy doesn't currently come with a way to do this.
Fortunately, [Blender] provides a [baking tool] as part of the Eevee
renderer, and its irradiance volumes are compatible with those used by
Bevy.
The [`bevy-baked-gi`] project provides a tool, `export-blender-gi`, that
can
extract the baked irradiance volumes from the Blender `.blend` file and
package them up into a `.ktx2` texture for use by the engine. See the
documentation in the `bevy-baked-gi` project for more details as to this
workflow.
Like all light probes in Bevy, irradiance volumes are 1×1×1 cubes that
can
be arbitrarily scaled, rotated, and positioned in a scene with the
[`bevy_transform::components::Transform`] component. The 3D voxel grid
will
be stretched to fill the interior of the cube, and the illumination from
the
irradiance volume will apply to all fragments within that bounding
region.
Bevy's irradiance volumes are based on Valve's [*ambient cubes*] as used
in
*Half-Life 2* ([Mitchell 2006], slide 27). These encode a single color
of
light from the six 3D cardinal directions and blend the sides together
according to the surface normal.
The primary reason for choosing ambient cubes is to match Blender, so
that
its Eevee renderer can be used for baking. However, they also have some
advantages over the common second-order spherical harmonics approach:
ambient cubes don't suffer from ringing artifacts, they are smaller (6
colors for ambient cubes as opposed to 9 for spherical harmonics), and
evaluation is faster. A smaller basis allows for a denser grid of voxels
with the same storage requirements.
If you wish to use a tool other than `export-blender-gi` to produce the
irradiance volumes, you'll need to pack the irradiance volumes in the
following format. The irradiance volume of resolution *(Rx, Ry, Rz)* is
expected to be a 3D texture of dimensions *(Rx, 2Ry, 3Rz)*. The
unnormalized
texture coordinate *(s, t, p)* of the voxel at coordinate *(x, y, z)*
with
side *S* ∈ *{-X, +X, -Y, +Y, -Z, +Z}* is as follows:
```text
s = x
t = y + ⎰ 0 if S ∈ {-X, -Y, -Z}
⎱ Ry if S ∈ {+X, +Y, +Z}
⎧ 0 if S ∈ {-X, +X}
p = z + ⎨ Rz if S ∈ {-Y, +Y}
⎩ 2Rz if S ∈ {-Z, +Z}
```
Visually, in a left-handed coordinate system with Y up, viewed from the
right, the 3D texture looks like a stacked series of voxel grids, one
for
each cube side, in this order:
| **+X** | **+Y** | **+Z** |
| ------ | ------ | ------ |
| **-X** | **-Y** | **-Z** |
A terminology note: Other engines may refer to irradiance volumes as
*voxel
global illumination*, *VXGI*, or simply as *light probes*. Sometimes
*light
probe* refers to what Bevy calls a reflection probe. In Bevy, *light
probe*
is a generic term that encompasses all cuboid bounding regions that
capture
indirect illumination, whether based on voxels or not.
Note that, if binding arrays aren't supported (e.g. on WebGPU or WebGL
2),
then only the closest irradiance volume to the view will be taken into
account during rendering.
[*ambient cubes*]:
https://advances.realtimerendering.com/s2006/Mitchell-ShadingInValvesSourceEngine.pdf
[Mitchell 2006]:
https://advances.realtimerendering.com/s2006/Mitchell-ShadingInValvesSourceEngine.pdf
[Blender]: http://blender.org/
[baking tool]:
https://docs.blender.org/manual/en/latest/render/eevee/render_settings/indirect_lighting.html
[`bevy-baked-gi`]: https://github.com/pcwalton/bevy-baked-gi
### Implementation notes
This patch generalizes light probes so as to reuse as much code as
possible between irradiance volumes and the existing reflection probes.
This approach was chosen because both techniques share numerous
similarities:
1. Both irradiance volumes and reflection probes are cuboid bounding
regions.
2. Both are responsible for providing baked indirect light.
3. Both techniques involve presenting a variable number of textures to
the shader from which indirect light is sampled. (In the current
implementation, this uses binding arrays.)
4. Both irradiance volumes and reflection probes require gathering and
sorting probes by distance on CPU.
5. Both techniques require the GPU to search through a list of bounding
regions.
6. Both will eventually want to have falloff so that we can smoothly
blend as objects enter and exit the probes' influence ranges. (This is
not implemented yet to keep this patch relatively small and reviewable.)
To do this, we generalize most of the methods in the reflection probes
patch #11366 to be generic over a trait, `LightProbeComponent`. This
trait is implemented by both `EnvironmentMapLight` (for reflection
probes) and `IrradianceVolume` (for irradiance volumes). Using a trait
will allow us to add more types of light probes in the future. In
particular, I highly suspect we will want real-time reflection planes
for mirrors in the future, which can be easily slotted into this
framework.
## Changelog
> This section is optional. If this was a trivial fix, or has no
externally-visible impact, you can delete this section.
### Added
* A new `IrradianceVolume` asset type is available for baked voxelized
light probes. You can bake the global illumination using Blender or
another tool of your choice and use it in Bevy to apply indirect
illumination to dynamic objects.
# Objective
- Address #10338
## Solution
- When implementing specular and diffuse transmission, I inadvertently
introduced a performance regression. On high-end hardware it is barely
noticeable, but **for lower-end hardware it can be pretty brutal**. If I
understand it correctly, this is likely due to use of masking by the GPU
to implement control flow, which means that you still pay the price for
the branches you don't take;
- To avoid that, this PR introduces new shader defs (controlled via
`StandardMaterialKey`) that conditionally include the transmission
logic, that way the shader code for both types of transmission isn't
even sent to the GPU if you're not using them;
- This PR also renames ~~`STANDARDMATERIAL_NORMAL_MAP`~~ to
`STANDARD_MATERIAL_NORMAL_MAP` for consistency with the naming
convention used elsewhere in the codebase. (Drive-by fix)
---
## Changelog
- Added new shader defs, set when using transmission in the
`StandardMaterial`:
- `STANDARD_MATERIAL_SPECULAR_TRANSMISSION`;
- `STANDARD_MATERIAL_DIFFUSE_TRANSMISSION`;
- `STANDARD_MATERIAL_SPECULAR_OR_DIFFUSE_TRANSMISSION`.
- Fixed performance regression caused by the introduction of
transmission, by gating transmission shader logic behind the newly
introduced shader defs;
- Renamed ~~`STANDARDMATERIAL_NORMAL_MAP`~~ to
`STANDARD_MATERIAL_NORMAL_MAP` for consistency;
## Migration Guide
- If you were using `#ifdef STANDARDMATERIAL_NORMAL_MAP` on your shader
code, make sure to update the name to `STANDARD_MATERIAL_NORMAL_MAP`;
(with an underscore between `STANDARD` and `MATERIAL`)
# Objective
- Addresses **Support processing and loading files without extensions**
from #9714
- Addresses **More runtime loading configuration** from #9714
- Fixes#367
- Fixes#10703
## Solution
`AssetServer::load::<A>` and `AssetServer::load_with_settings::<A>` can
now use the `Asset` type parameter `A` to select a registered
`AssetLoader` without inspecting the provided `AssetPath`. This change
cascades onto `LoadContext::load` and `LoadContext::load_with_settings`.
This allows the loading of assets which have incorrect or ambiguous file
extensions.
```rust
// Allow the type to be inferred by context
let handle = asset_server.load("data/asset_no_extension");
// Hint the type through the handle
let handle: Handle<CustomAsset> = asset_server.load("data/asset_no_extension");
// Explicit through turbofish
let handle = asset_server.load::<CustomAsset>("data/asset_no_extension");
```
Since a single `AssetPath` no longer maps 1:1 with an `Asset`, I've also
modified how assets are loaded to permit multiple asset types to be
loaded from a single path. This allows for two different `AssetLoaders`
(which return different types of assets) to both load a single path (if
requested).
```rust
// Uses GltfLoader
let model = asset_server.load::<Gltf>("cube.gltf");
// Hypothetical Blob loader for data transmission (for example)
let blob = asset_server.load::<Blob>("cube.gltf");
```
As these changes are reflected in the `LoadContext` as well as the
`AssetServer`, custom `AssetLoaders` can also take advantage of this
behaviour to create more complex assets.
---
## Change Log
- Updated `custom_asset` example to demonstrate extension-less assets.
- Added `AssetServer::get_handles_untyped` and Added
`AssetServer::get_path_ids`
## Notes
As a part of that refactor, I chose to store `AssetLoader`s (within
`AssetLoaders`) using a `HashMap<TypeId, ...>` instead of a `Vec<...>`.
My reasoning for this was I needed to add a relationship between `Asset`
`TypeId`s and the `AssetLoader`, so instead of having a `Vec` and a
`HashMap`, I combined the two, removing the `usize` index from the
adjacent maps.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Since #9907 the generation starts at `1` instead of `0` so
`Entity::to_bits` now returns `4294967296` (ie. `u32::MAX + 1`) as the
lowest number instead of `0`.
Without this change scene loading fails with this error message:
`ERROR bevy_asset::server: Failed to load asset
'scenes/load_scene_example.scn.ron' with asset loader
'bevy_scene::scene_loader::SceneLoader': Could not parse RON: 8:6:
Invalid generation bits`
This pull request re-submits #10057, which was backed out for breaking
macOS, iOS, and Android. I've tested this version on macOS and Android
and on the iOS simulator.
# Objective
This pull request implements *reflection probes*, which generalize
environment maps to allow for multiple environment maps in the same
scene, each of which has an axis-aligned bounding box. This is a
standard feature of physically-based renderers and was inspired by [the
corresponding feature in Blender's Eevee renderer].
## Solution
This is a minimal implementation of reflection probes that allows
artists to define cuboid bounding regions associated with environment
maps. For every view, on every frame, a system builds up a list of the
nearest 4 reflection probes that are within the view's frustum and
supplies that list to the shader. The PBR fragment shader searches
through the list, finds the first containing reflection probe, and uses
it for indirect lighting, falling back to the view's environment map if
none is found. Both forward and deferred renderers are fully supported.
A reflection probe is an entity with a pair of components, *LightProbe*
and *EnvironmentMapLight* (as well as the standard *SpatialBundle*, to
position it in the world). The *LightProbe* component (along with the
*Transform*) defines the bounding region, while the
*EnvironmentMapLight* component specifies the associated diffuse and
specular cubemaps.
A frequent question is "why two components instead of just one?" The
advantages of this setup are:
1. It's readily extensible to other types of light probes, in particular
*irradiance volumes* (also known as ambient cubes or voxel global
illumination), which use the same approach of bounding cuboids. With a
single component that applies to both reflection probes and irradiance
volumes, we can share the logic that implements falloff and blending
between multiple light probes between both of those features.
2. It reduces duplication between the existing *EnvironmentMapLight* and
these new reflection probes. Systems can treat environment maps attached
to cameras the same way they treat environment maps applied to
reflection probes if they wish.
Internally, we gather up all environment maps in the scene and place
them in a cubemap array. At present, this means that all environment
maps must have the same size, mipmap count, and texture format. A
warning is emitted if this restriction is violated. We could potentially
relax this in the future as part of the automatic mipmap generation
work, which could easily do texture format conversion as part of its
preprocessing.
An easy way to generate reflection probe cubemaps is to bake them in
Blender and use the `export-blender-gi` tool that's part of the
[`bevy-baked-gi`] project. This tool takes a `.blend` file containing
baked cubemaps as input and exports cubemap images, pre-filtered with an
embedded fork of the [glTF IBL Sampler], alongside a corresponding
`.scn.ron` file that the scene spawner can use to recreate the
reflection probes.
Note that this is intentionally a minimal implementation, to aid
reviewability. Known issues are:
* Reflection probes are basically unsupported on WebGL 2, because WebGL
2 has no cubemap arrays. (Strictly speaking, you can have precisely one
reflection probe in the scene if you have no other cubemaps anywhere,
but this isn't very useful.)
* Reflection probes have no falloff, so reflections will abruptly change
when objects move from one bounding region to another.
* As mentioned before, all cubemaps in the world of a given type
(diffuse or specular) must have the same size, format, and mipmap count.
Future work includes:
* Blending between multiple reflection probes.
* A falloff/fade-out region so that reflected objects disappear
gradually instead of vanishing all at once.
* Irradiance volumes for voxel-based global illumination. This should
reuse much of the reflection probe logic, as they're both GI techniques
based on cuboid bounding regions.
* Support for WebGL 2, by breaking batches when reflection probes are
used.
These issues notwithstanding, I think it's best to land this with
roughly the current set of functionality, because this patch is useful
as is and adding everything above would make the pull request
significantly larger and harder to review.
---
## Changelog
### Added
* A new *LightProbe* component is available that specifies a bounding
region that an *EnvironmentMapLight* applies to. The combination of a
*LightProbe* and an *EnvironmentMapLight* offers *reflection probe*
functionality similar to that available in other engines.
[the corresponding feature in Blender's Eevee renderer]:
https://docs.blender.org/manual/en/latest/render/eevee/light_probes/reflection_cubemaps.html
[`bevy-baked-gi`]: https://github.com/pcwalton/bevy-baked-gi
[glTF IBL Sampler]: https://github.com/KhronosGroup/glTF-IBL-Sampler
> Replaces #5213
# Objective
Implement sprite tiling and [9 slice
scaling](https://en.wikipedia.org/wiki/9-slice_scaling) for
`bevy_sprite`.
Allowing slice scaling and texture tiling.
Basic scaling vs 9 slice scaling:
Slicing example:
<img width="481" alt="Screenshot 2022-07-05 at 15 05 49"
src="https://user-images.githubusercontent.com/26703856/177336112-9e961af0-c0af-4197-aec9-430c1170a79d.png">
Tiling example:
<img width="1329" alt="Screenshot 2023-11-16 at 13 53 32"
src="https://github.com/bevyengine/bevy/assets/26703856/14db39b7-d9e0-4bc3-ba0e-b1f2db39ae8f">
# Solution
- `SpriteBundlue` now has a `scale_mode` component storing a
`SpriteScaleMode` enum with three variants:
- `Stretched` (default)
- `Tiled` to have sprites tile horizontally and/or vertically
- `Sliced` allowing 9 slicing the texture and optionally tile some
sections with a `Textureslicer`.
- `bevy_sprite` has two extra systems to compute a
`ComputedTextureSlices` if necessary,:
- One system react to changes on `Sprite`, `Handle<Image>` or
`SpriteScaleMode`
- The other listens to `AssetEvent<Image>` to compute slices on sprites
when the texture is ready or changed
- I updated the `bevy_sprite` extraction stage to extract potentially
multiple textures instead of one, depending on the presence of
`ComputedTextureSlices`
- I added two examples showcasing the slicing and tiling feature.
The addition of `ComputedTextureSlices` as a cache is to avoid querying
the image data, to retrieve its dimensions, every frame in a extract or
prepare stage. Also it reacts to changes so we can have stuff like this
(tiling example):
https://github.com/bevyengine/bevy/assets/26703856/a349a9f3-33c3-471f-8ef4-a0e5dfce3b01
# Related
- [ ] Once #5103 or #10099 is merged I can enable tiling and slicing for
texture sheets as ui
# To discuss
There is an other option, to consider slice/tiling as part of the asset,
using the new asset preprocessing but I have no clue on how to do it.
Also, instead of retrieving the Image dimensions, we could use the same
system as the sprite sheet and have the user give the image dimensions
directly (grid). But I think it's less user friendly
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
# Objective
This pull request implements *reflection probes*, which generalize
environment maps to allow for multiple environment maps in the same
scene, each of which has an axis-aligned bounding box. This is a
standard feature of physically-based renderers and was inspired by [the
corresponding feature in Blender's Eevee renderer].
## Solution
This is a minimal implementation of reflection probes that allows
artists to define cuboid bounding regions associated with environment
maps. For every view, on every frame, a system builds up a list of the
nearest 4 reflection probes that are within the view's frustum and
supplies that list to the shader. The PBR fragment shader searches
through the list, finds the first containing reflection probe, and uses
it for indirect lighting, falling back to the view's environment map if
none is found. Both forward and deferred renderers are fully supported.
A reflection probe is an entity with a pair of components, *LightProbe*
and *EnvironmentMapLight* (as well as the standard *SpatialBundle*, to
position it in the world). The *LightProbe* component (along with the
*Transform*) defines the bounding region, while the
*EnvironmentMapLight* component specifies the associated diffuse and
specular cubemaps.
A frequent question is "why two components instead of just one?" The
advantages of this setup are:
1. It's readily extensible to other types of light probes, in particular
*irradiance volumes* (also known as ambient cubes or voxel global
illumination), which use the same approach of bounding cuboids. With a
single component that applies to both reflection probes and irradiance
volumes, we can share the logic that implements falloff and blending
between multiple light probes between both of those features.
2. It reduces duplication between the existing *EnvironmentMapLight* and
these new reflection probes. Systems can treat environment maps attached
to cameras the same way they treat environment maps applied to
reflection probes if they wish.
Internally, we gather up all environment maps in the scene and place
them in a cubemap array. At present, this means that all environment
maps must have the same size, mipmap count, and texture format. A
warning is emitted if this restriction is violated. We could potentially
relax this in the future as part of the automatic mipmap generation
work, which could easily do texture format conversion as part of its
preprocessing.
An easy way to generate reflection probe cubemaps is to bake them in
Blender and use the `export-blender-gi` tool that's part of the
[`bevy-baked-gi`] project. This tool takes a `.blend` file containing
baked cubemaps as input and exports cubemap images, pre-filtered with an
embedded fork of the [glTF IBL Sampler], alongside a corresponding
`.scn.ron` file that the scene spawner can use to recreate the
reflection probes.
Note that this is intentionally a minimal implementation, to aid
reviewability. Known issues are:
* Reflection probes are basically unsupported on WebGL 2, because WebGL
2 has no cubemap arrays. (Strictly speaking, you can have precisely one
reflection probe in the scene if you have no other cubemaps anywhere,
but this isn't very useful.)
* Reflection probes have no falloff, so reflections will abruptly change
when objects move from one bounding region to another.
* As mentioned before, all cubemaps in the world of a given type
(diffuse or specular) must have the same size, format, and mipmap count.
Future work includes:
* Blending between multiple reflection probes.
* A falloff/fade-out region so that reflected objects disappear
gradually instead of vanishing all at once.
* Irradiance volumes for voxel-based global illumination. This should
reuse much of the reflection probe logic, as they're both GI techniques
based on cuboid bounding regions.
* Support for WebGL 2, by breaking batches when reflection probes are
used.
These issues notwithstanding, I think it's best to land this with
roughly the current set of functionality, because this patch is useful
as is and adding everything above would make the pull request
significantly larger and harder to review.
---
## Changelog
### Added
* A new *LightProbe* component is available that specifies a bounding
region that an *EnvironmentMapLight* applies to. The combination of a
*LightProbe* and an *EnvironmentMapLight* offers *reflection probe*
functionality similar to that available in other engines.
[the corresponding feature in Blender's Eevee renderer]:
https://docs.blender.org/manual/en/latest/render/eevee/light_probes/reflection_cubemaps.html
[`bevy-baked-gi`]: https://github.com/pcwalton/bevy-baked-gi
[glTF IBL Sampler]: https://github.com/KhronosGroup/glTF-IBL-Sampler
# Objective
Lightmaps, textures that store baked global illumination, have been a
mainstay of real-time graphics for decades. Bevy currently has no
support for them, so this pull request implements them.
## Solution
The new `Lightmap` component can be attached to any entity that contains
a `Handle<Mesh>` and a `StandardMaterial`. When present, it will be
applied in the PBR shader. Because multiple lightmaps are frequently
packed into atlases, each lightmap may have its own UV boundaries within
its texture. An `exposure` field is also provided, to control the
brightness of the lightmap.
Note that this PR doesn't provide any way to bake the lightmaps. That
can be done with [The Lightmapper] or another solution, such as Unity's
Bakery.
---
## Changelog
### Added
* A new component, `Lightmap`, is available, for baked global
illumination. If your mesh has a second UV channel (UV1), and you attach
this component to the entity with that mesh, Bevy will apply the texture
referenced in the lightmap.
[The Lightmapper]: https://github.com/Naxela/The_Lightmapper
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Provide an example of how to achieve pixel-perfect "grid snapping" in 2D
via rendering to a texture. This is a common use case in retro pixel art
game development.
## Solution
Render sprites to a canvas via a Camera, then use another (scaled up)
Camera to render the resulting canvas to the screen. This example is
based on the `3d/render_to_texture.rs` example. Furthermore, this
example demonstrates mixing retro-style graphics with high-resolution
graphics, as well as pixel-snapped rendering of a
`MaterialMesh2dBundle`.
# Objective
- Materials should be a more frequent rebind then meshes (due to being
able to use a single vertex buffer, such as in #10164) and therefore
should be in a higher bind group.
---
## Changelog
- For 2d and 3d mesh/material setups (but not UI materials, or other
rendering setups such as gizmos, sprites, or text), mesh data is now in
bind group 1, and material data is now in bind group 2, which is swapped
from how they were before.
## Migration Guide
- Custom 2d and 3d mesh/material shaders should now use bind group 2
`@group(2) @binding(x)` for their bound resources, instead of bind group
1.
- Many internal pieces of rendering code have changed so that mesh data
is now in bind group 1, and material data is now in bind group 2.
Semi-custom rendering setups (that don't use the Material or Material2d
APIs) should adapt to these changes.
# Objective
- The current shader code is misleading since it makes it look like a
struct is passed to the bind group 0 but in reality only the color is
passed. They just happen to have the exact same memory layout so wgsl
doesn't complain and it works.
- The struct is defined after the `impl Material` block which is
backwards from pretty much every other usage of the `impl` block in
bevy.
## Solution
- Remove the unnecessary struct in the shader
- move the impl block
# Objective
- Fixes#10518
## Solution
I've added a method to `LoadContext`, `load_direct_with_reader`, which
mirrors the behaviour of `load_direct` with a single key difference: it
is provided with the `Reader` by the caller, rather than getting it from
the contained `AssetServer`. This allows for an `AssetLoader` to process
its `Reader` stream, and then directly hand the results off to the
`LoadContext` to handle further loading. The outer `AssetLoader` can
control how the `Reader` is interpreted by providing a relevant
`AssetPath`.
For example, a Gzip decompression loader could process the asset
`images/my_image.png.gz` by decompressing the bytes, then handing the
decompressed result to the `LoadContext` with the new path
`images/my_image.png.gz/my_image.png`. This intuitively reflects the
nature of contained assets, whilst avoiding unintended behaviour, since
the generated path cannot be a real file path (a file and folder of the
same name cannot coexist in most file-systems).
```rust
#[derive(Asset, TypePath)]
pub struct GzAsset {
pub uncompressed: ErasedLoadedAsset,
}
#[derive(Default)]
pub struct GzAssetLoader;
impl AssetLoader for GzAssetLoader {
type Asset = GzAsset;
type Settings = ();
type Error = GzAssetLoaderError;
fn load<'a>(
&'a self,
reader: &'a mut Reader,
_settings: &'a (),
load_context: &'a mut LoadContext,
) -> BoxedFuture<'a, Result<Self::Asset, Self::Error>> {
Box::pin(async move {
let compressed_path = load_context.path();
let file_name = compressed_path
.file_name()
.ok_or(GzAssetLoaderError::IndeterminateFilePath)?
.to_string_lossy();
let uncompressed_file_name = file_name
.strip_suffix(".gz")
.ok_or(GzAssetLoaderError::IndeterminateFilePath)?;
let contained_path = compressed_path.join(uncompressed_file_name);
let mut bytes_compressed = Vec::new();
reader.read_to_end(&mut bytes_compressed).await?;
let mut decoder = GzDecoder::new(bytes_compressed.as_slice());
let mut bytes_uncompressed = Vec::new();
decoder.read_to_end(&mut bytes_uncompressed)?;
// Now that we have decompressed the asset, let's pass it back to the
// context to continue loading
let mut reader = VecReader::new(bytes_uncompressed);
let uncompressed = load_context
.load_direct_with_reader(&mut reader, contained_path)
.await?;
Ok(GzAsset { uncompressed })
})
}
fn extensions(&self) -> &[&str] {
&["gz"]
}
}
```
Because this example is so prudent, I've included an
`asset_decompression` example which implements this exact behaviour:
```rust
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.init_asset::<GzAsset>()
.init_asset_loader::<GzAssetLoader>()
.add_systems(Startup, setup)
.add_systems(Update, decompress::<Image>)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera2dBundle::default());
commands.spawn((
Compressed::<Image> {
compressed: asset_server.load("data/compressed_image.png.gz"),
..default()
},
Sprite::default(),
TransformBundle::default(),
VisibilityBundle::default(),
));
}
fn decompress<A: Asset>(
mut commands: Commands,
asset_server: Res<AssetServer>,
mut compressed_assets: ResMut<Assets<GzAsset>>,
query: Query<(Entity, &Compressed<A>)>,
) {
for (entity, Compressed { compressed, .. }) in query.iter() {
let Some(GzAsset { uncompressed }) = compressed_assets.remove(compressed) else {
continue;
};
let uncompressed = uncompressed.take::<A>().unwrap();
commands
.entity(entity)
.remove::<Compressed<A>>()
.insert(asset_server.add(uncompressed));
}
}
```
A key limitation to this design is how to type the internally loaded
asset, since the example `GzAssetLoader` is unaware of the internal
asset type `A`. As such, in this example I store the contained asset as
an `ErasedLoadedAsset`, and leave it up to the consumer of the `GzAsset`
to handle typing the final result, which is the purpose of the
`decompress` system. This limitation can be worked around by providing
type information to the `GzAssetLoader`, such as `GzAssetLoader<Image,
ImageAssetLoader>`, but this would require registering the asset loader
for every possible decompression target.
Aside from this limitation, nested asset containerisation works as an
end user would expect; if the user registers a `TarAssetLoader`, and a
`GzAssetLoader`, then they can load assets with compound
containerisation, such as `images.tar.gz`.
---
## Changelog
- Added `LoadContext::load_direct_with_reader`
- Added `asset_decompression` example
## Notes
- While I believe my implementation of a Gzip asset loader is
reasonable, I haven't included it as a public feature of `bevy_asset` to
keep the scope of this PR as focussed as possible.
- I have included `flate2` as a `dev-dependency` for the example; it is
not included in the main dependency graph.
# Objective
- 2d materials have subtle differences with 3d materials that aren't
obvious to beginners
## Solution
- Add an example that shows how to make a 2d material
# Objective
- Changes the default clear color to match the code block color on
Bevy's website.
## Solution
- Changed the clear color, updated text in examples to ensure adequate
contrast. Inconsistent usage of white text color set to use the default
color instead, which is already white.
- Additionally, updated the `3d_scene` example to make it look a bit
better, and use bevy's branding colors.
# Objective
- bump naga_oil to 0.10
- update shader imports to use rusty syntax
## Migration Guide
naga_oil 0.10 reworks the import mechanism to support more syntax to
make it more rusty, and test for item use before importing to determine
which imports are modules and which are items, which allows:
- use rust-style imports
```
#import bevy_pbr::{
pbr_functions::{alpha_discard as discard, apply_pbr_lighting},
mesh_bindings,
}
```
- import partial paths:
```
#import part::of::path
...
path::remainder::function();
```
which will call to `part::of::path::remainder::function`
- use fully qualified paths without importing:
```
// #import bevy_pbr::pbr_functions
bevy_pbr::pbr_functions::pbr()
```
- use imported items without qualifying
```
#import bevy_pbr::pbr_functions::pbr
// for backwards compatibility the old style is still supported:
// #import bevy_pbr::pbr_functions pbr
...
pbr()
```
- allows most imported items to end with `_` and numbers (naga_oil#30).
still doesn't allow struct members to end with `_` or numbers but it's
progress.
- the vast majority of existing shader code will work without changes,
but will emit "deprecated" warnings for old-style imports. these can be
suppressed with the `allow-deprecated` feature.
- partly breaks overrides (as far as i'm aware nobody uses these yet) -
now overrides will only be applied if the overriding module is added as
an additional import in the arguments to `Composer::make_naga_module` or
`Composer::add_composable_module`. this is necessary to support
determining whether imports are modules or items.
# Objective
allow extending `Material`s (including the built in `StandardMaterial`)
with custom vertex/fragment shaders and additional data, to easily get
pbr lighting with custom modifications, or otherwise extend a base
material.
# Solution
- added `ExtendedMaterial<B: Material, E: MaterialExtension>` which
contains a base material and a user-defined extension.
- added example `extended_material` showing how to use it
- modified AsBindGroup to have "unprepared" functions that return raw
resources / layout entries so that the extended material can combine
them
note: doesn't currently work with array resources, as i can't figure out
how to make the OwnedBindingResource::get_binding() work, as wgpu
requires a `&'a[&'a TextureView]` and i have a `Vec<TextureView>`.
# Migration Guide
manual implementations of `AsBindGroup` will need to be adjusted, the
changes are pretty straightforward and can be seen in the diff for e.g.
the `texture_binding_array` example.
---------
Co-authored-by: Robert Swain <robert.swain@gmail.com>
# Objective
cleanup some pbr shader code. improve shader stage io consistency and
make pbr.wgsl (probably many people's first foray into bevy shader code)
a little more human-readable. also fix a couple of small issues with
deferred rendering.
## Solution
mesh_vertex_output:
- rename to forward_io (to align with prepass_io)
- rename `MeshVertexOutput` to `VertexOutput` (to align with prepass_io)
- move `Vertex` from mesh.wgsl into here (to align with prepass_io)
prepass_io:
- remove `FragmentInput`, use `VertexOutput` directly (to align with
forward_io)
- rename `VertexOutput::clip_position` to `position` (to align with
forward_io)
pbr.wgsl:
- restructure so we don't need `#ifdefs` on the actual entrypoint, use
VertexOutput and FragmentOutput in all cases and use #ifdefs to import
the right struct definitions.
- rearrange to make the flow clearer
- move alpha_discard up from `pbr_functions::pbr` to avoid needing to
call it on some branches and not others
- add a bunch of comments
deferred_lighting:
- move ssao into the `!unlit` block to reflect forward behaviour
correctly
- fix compile error with deferred + premultiply_alpha
## Migration Guide
in custom material shaders:
- `pbr_functions::pbr` no longer calls to
`pbr_functions::alpha_discard`. if you were using the `pbr` function in
a custom shader with alpha mask mode you now also need to call
alpha_discard manually
- rename imports of `bevy_pbr::mesh_vertex_output` to
`bevy_pbr::forward_io`
- rename instances of `MeshVertexOutput` to `VertexOutput`
in custom material prepass shaders:
- rename instances of `VertexOutput::clip_position` to
`VertexOutput::position`
# Objective
- Add a [Deferred
Renderer](https://en.wikipedia.org/wiki/Deferred_shading) to Bevy.
- This allows subsequent passes to access per pixel material information
before/during shading.
- Accessing this per pixel material information is needed for some
features, like GI. It also makes other features (ex. Decals) simpler to
implement and/or improves their capability. There are multiple
approaches to accomplishing this. The deferred shading approach works
well given the limitations of WebGPU and WebGL2.
Motivation: [I'm working on a GI solution for
Bevy](https://youtu.be/eH1AkL-mwhI)
# Solution
- The deferred renderer is implemented with a prepass and a deferred
lighting pass.
- The prepass renders opaque objects into the Gbuffer attachment
(`Rgba32Uint`). The PBR shader generates a `PbrInput` in mostly the same
way as the forward implementation and then [packs it into the
Gbuffer](ec1465559f/crates/bevy_pbr/src/render/pbr.wgsl (L168)).
- The deferred lighting pass unpacks the `PbrInput` and [feeds it into
the pbr()
function](ec1465559f/crates/bevy_pbr/src/deferred/deferred_lighting.wgsl (L65)),
then outputs the shaded color data.
- There is now a resource
[DefaultOpaqueRendererMethod](ec1465559f/crates/bevy_pbr/src/material.rs (L599))
that can be used to set the default render method for opaque materials.
If materials return `None` from
[opaque_render_method()](ec1465559f/crates/bevy_pbr/src/material.rs (L131))
the `DefaultOpaqueRendererMethod` will be used. Otherwise, custom
materials can also explicitly choose to only support Deferred or Forward
by returning the respective
[OpaqueRendererMethod](ec1465559f/crates/bevy_pbr/src/material.rs (L603))
- Deferred materials can be used seamlessly along with both opaque and
transparent forward rendered materials in the same scene. The [deferred
rendering
example](https://github.com/DGriffin91/bevy/blob/deferred/examples/3d/deferred_rendering.rs)
does this.
- The deferred renderer does not support MSAA. If any deferred materials
are used, MSAA must be disabled. Both TAA and FXAA are supported.
- Deferred rendering supports WebGL2/WebGPU.
## Custom deferred materials
- Custom materials can support both deferred and forward at the same
time. The
[StandardMaterial](ec1465559f/crates/bevy_pbr/src/render/pbr.wgsl (L166))
does this. So does [this
example](https://github.com/DGriffin91/bevy_glowy_orb_tutorial/blob/deferred/assets/shaders/glowy.wgsl#L56).
- Custom deferred materials that require PBR lighting can create a
`PbrInput`, write it to the deferred GBuffer and let it be rendered by
the `PBRDeferredLightingPlugin`.
- Custom deferred materials that require custom lighting have two
options:
1. Use the base_color channel of the `PbrInput` combined with the
`STANDARD_MATERIAL_FLAGS_UNLIT_BIT` flag.
[Example.](https://github.com/DGriffin91/bevy_glowy_orb_tutorial/blob/deferred/assets/shaders/glowy.wgsl#L56)
(If the unlit bit is set, the base_color is stored as RGB9E5 for extra
precision)
2. A Custom Deferred Lighting pass can be created, either overriding the
default, or running in addition. The a depth buffer is used to limit
rendering to only the required fragments for each deferred lighting
pass. Materials can set their respective depth id via the
[deferred_lighting_pass_id](b79182d2a3/crates/bevy_pbr/src/prepass/prepass_io.wgsl (L95))
attachment. The custom deferred lighting pass plugin can then set [its
corresponding
depth](ec1465559f/crates/bevy_pbr/src/deferred/deferred_lighting.wgsl (L37)).
Then with the lighting pass using
[CompareFunction::Equal](ec1465559f/crates/bevy_pbr/src/deferred/mod.rs (L335)),
only the fragments with a depth that equal the corresponding depth
written in the material will be rendered.
Custom deferred lighting plugins can also be created to render the
StandardMaterial. The default deferred lighting plugin can be bypassed
with `DefaultPlugins.set(PBRDeferredLightingPlugin { bypass: true })`
---------
Co-authored-by: nickrart <nickolas.g.russell@gmail.com>
# Objective
assets v2 broke custom shader imports. fix them
## Solution
store handles of any file dependencies in the `Shader` to avoid them
being immediately dropped.
also added a use into the `shader_material` example so that it'll be
harder to break support in future.
# Objective
- Implement the foundations of automatic batching/instancing of draw
commands as the next step from #89
- NOTE: More performance improvements will come when more data is
managed and bound in ways that do not require rebinding such as mesh,
material, and texture data.
## Solution
- The core idea for batching of draw commands is to check whether any of
the information that has to be passed when encoding a draw command
changes between two things that are being drawn according to the sorted
render phase order. These should be things like the pipeline, bind
groups and their dynamic offsets, index/vertex buffers, and so on.
- The following assumptions have been made:
- Only entities with prepared assets (pipelines, materials, meshes) are
queued to phases
- View bindings are constant across a phase for a given draw function as
phases are per-view
- `batch_and_prepare_render_phase` is the only system that performs this
batching and has sole responsibility for preparing the per-object data.
As such the mesh binding and dynamic offsets are assumed to only vary as
a result of the `batch_and_prepare_render_phase` system, e.g. due to
having to split data across separate uniform bindings within the same
buffer due to the maximum uniform buffer binding size.
- Implement `GpuArrayBuffer` for `Mesh2dUniform` to store Mesh2dUniform
in arrays in GPU buffers rather than each one being at a dynamic offset
in a uniform buffer. This is the same optimisation that was made for 3D
not long ago.
- Change batch size for a range in `PhaseItem`, adding API for getting
or mutating the range. This is more flexible than a size as the length
of the range can be used in place of the size, but the start and end can
be otherwise whatever is needed.
- Add an optional mesh bind group dynamic offset to `PhaseItem`. This
avoids having to do a massive table move just to insert
`GpuArrayBufferIndex` components.
## Benchmarks
All tests have been run on an M1 Max on AC power. `bevymark` and
`many_cubes` were modified to use 1920x1080 with a scale factor of 1. I
run a script that runs a separate Tracy capture process, and then runs
the bevy example with `--features bevy_ci_testing,trace_tracy` and
`CI_TESTING_CONFIG=../benchmark.ron` with the contents of
`../benchmark.ron`:
```rust
(
exit_after: Some(1500)
)
```
...in order to run each test for 1500 frames.
The recent changes to `many_cubes` and `bevymark` added reproducible
random number generation so that with the same settings, the same rng
will occur. They also added benchmark modes that use a fixed delta time
for animations. Combined this means that the same frames should be
rendered both on main and on the branch.
The graphs compare main (yellow) to this PR (red).
### 3D Mesh `many_cubes --benchmark`
<img width="1411" alt="Screenshot 2023-09-03 at 23 42 10"
src="https://github.com/bevyengine/bevy/assets/302146/2088716a-c918-486c-8129-090b26fd2bc4">
The mesh and material are the same for all instances. This is basically
the best case for the initial batching implementation as it results in 1
draw for the ~11.7k visible meshes. It gives a ~30% reduction in median
frame time.
The 1000th frame is identical using the flip tool:
```
Mean: 0.000000
Weighted median: 0.000000
1st weighted quartile: 0.000000
3rd weighted quartile: 0.000000
Min: 0.000000
Max: 0.000000
Evaluation time: 0.4615 seconds
```
### 3D Mesh `many_cubes --benchmark --material-texture-count 10`
<img width="1404" alt="Screenshot 2023-09-03 at 23 45 18"
src="https://github.com/bevyengine/bevy/assets/302146/5ee9c447-5bd2-45c6-9706-ac5ff8916daf">
This run uses 10 different materials by varying their textures. The
materials are randomly selected, and there is no sorting by material
bind group for opaque 3D so any batching is 'random'. The PR produces a
~5% reduction in median frame time. If we were to sort the opaque phase
by the material bind group, then this should be a lot faster. This
produces about 10.5k draws for the 11.7k visible entities. This makes
sense as randomly selecting from 10 materials gives a chance that two
adjacent entities randomly select the same material and can be batched.
The 1000th frame is identical in flip:
```
Mean: 0.000000
Weighted median: 0.000000
1st weighted quartile: 0.000000
3rd weighted quartile: 0.000000
Min: 0.000000
Max: 0.000000
Evaluation time: 0.4537 seconds
```
### 3D Mesh `many_cubes --benchmark --vary-per-instance`
<img width="1394" alt="Screenshot 2023-09-03 at 23 48 44"
src="https://github.com/bevyengine/bevy/assets/302146/f02a816b-a444-4c18-a96a-63b5436f3b7f">
This run varies the material data per instance by randomly-generating
its colour. This is the worst case for batching and that it performs
about the same as `main` is a good thing as it demonstrates that the
batching has minimal overhead when dealing with ~11k visible mesh
entities.
The 1000th frame is identical according to flip:
```
Mean: 0.000000
Weighted median: 0.000000
1st weighted quartile: 0.000000
3rd weighted quartile: 0.000000
Min: 0.000000
Max: 0.000000
Evaluation time: 0.4568 seconds
```
### 2D Mesh `bevymark --benchmark --waves 160 --per-wave 1000 --mode
mesh2d`
<img width="1412" alt="Screenshot 2023-09-03 at 23 59 56"
src="https://github.com/bevyengine/bevy/assets/302146/cb02ae07-237b-4646-ae9f-fda4dafcbad4">
This spawns 160 waves of 1000 quad meshes that are shaded with
ColorMaterial. Each wave has a different material so 160 waves currently
should result in 160 batches. This results in a 50% reduction in median
frame time.
Capturing a screenshot of the 1000th frame main vs PR gives:
```
Mean: 0.001222
Weighted median: 0.750432
1st weighted quartile: 0.453494
3rd weighted quartile: 0.969758
Min: 0.000000
Max: 0.990296
Evaluation time: 0.4255 seconds
```
So they seem to produce the same results. I also double-checked the
number of draws. `main` does 160000 draws, and the PR does 160, as
expected.
### 2D Mesh `bevymark --benchmark --waves 160 --per-wave 1000 --mode
mesh2d --material-texture-count 10`
<img width="1392" alt="Screenshot 2023-09-04 at 00 09 22"
src="https://github.com/bevyengine/bevy/assets/302146/4358da2e-ce32-4134-82df-3ab74c40849c">
This generates 10 textures and generates materials for each of those and
then selects one material per wave. The median frame time is reduced by
50%. Similar to the plain run above, this produces 160 draws on the PR
and 160000 on `main` and the 1000th frame is identical (ignoring the fps
counter text overlay).
```
Mean: 0.002877
Weighted median: 0.964980
1st weighted quartile: 0.668871
3rd weighted quartile: 0.982749
Min: 0.000000
Max: 0.992377
Evaluation time: 0.4301 seconds
```
### 2D Mesh `bevymark --benchmark --waves 160 --per-wave 1000 --mode
mesh2d --vary-per-instance`
<img width="1396" alt="Screenshot 2023-09-04 at 00 13 53"
src="https://github.com/bevyengine/bevy/assets/302146/b2198b18-3439-47ad-919a-cdabe190facb">
This creates unique materials per instance by randomly-generating the
material's colour. This is the worst case for 2D batching. Somehow, this
PR manages a 7% reduction in median frame time. Both main and this PR
issue 160000 draws.
The 1000th frame is the same:
```
Mean: 0.001214
Weighted median: 0.937499
1st weighted quartile: 0.635467
3rd weighted quartile: 0.979085
Min: 0.000000
Max: 0.988971
Evaluation time: 0.4462 seconds
```
### 2D Sprite `bevymark --benchmark --waves 160 --per-wave 1000 --mode
sprite`
<img width="1396" alt="Screenshot 2023-09-04 at 12 21 12"
src="https://github.com/bevyengine/bevy/assets/302146/8b31e915-d6be-4cac-abf5-c6a4da9c3d43">
This just spawns 160 waves of 1000 sprites. There should be and is no
notable difference between main and the PR.
### 2D Sprite `bevymark --benchmark --waves 160 --per-wave 1000 --mode
sprite --material-texture-count 10`
<img width="1389" alt="Screenshot 2023-09-04 at 12 36 08"
src="https://github.com/bevyengine/bevy/assets/302146/45fe8d6d-c901-4062-a349-3693dd044413">
This spawns the sprites selecting a texture at random per instance from
the 10 generated textures. This has no significant change vs main and
shouldn't.
### 2D Sprite `bevymark --benchmark --waves 160 --per-wave 1000 --mode
sprite --vary-per-instance`
<img width="1401" alt="Screenshot 2023-09-04 at 12 29 52"
src="https://github.com/bevyengine/bevy/assets/302146/762c5c60-352e-471f-8dbe-bbf10e24ebd6">
This sets the sprite colour as being unique per instance. This can still
all be drawn using one batch. There should be no difference but the PR
produces median frame times that are 4% higher. Investigation showed no
clear sources of cost, rather a mix of give and take that should not
happen. It seems like noise in the results.
### Summary
| Benchmark | % change in median frame time |
| ------------- | ------------- |
| many_cubes | 🟩 -30% |
| many_cubes 10 materials | 🟩 -5% |
| many_cubes unique materials | 🟩 ~0% |
| bevymark mesh2d | 🟩 -50% |
| bevymark mesh2d 10 materials | 🟩 -50% |
| bevymark mesh2d unique materials | 🟩 -7% |
| bevymark sprite | 🟥 2% |
| bevymark sprite 10 materials | 🟥 0.6% |
| bevymark sprite unique materials | 🟥 4.1% |
---
## Changelog
- Added: 2D and 3D mesh entities that share the same mesh and material
(same textures, same data) are now batched into the same draw command
for better performance.
---------
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Nicola Papale <nico@nicopap.ch>
# Objective
- When adding/removing bindings in large binding lists, git would
generate very difficult-to-read diffs
## Solution
- Move the `@group(X) @binding(Y)` into the same line as the binding
type declaration
# 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);
```
