# Objective
- Fix `post_processing` and `shader_prepass` examples as they fail when compiling shaders due to missing shader defs
- Fixes#6799
- Fixes#6996
- Fixes#7375
- Supercedes #6997
- Supercedes #7380
## Solution
- The prepass was broken due to a missing `MAX_CASCADES_PER_LIGHT` shader def. Add it.
- The shader used in the `post_processing` example is applied to a 2D mesh, so use the correct mesh2d_view_bindings shader import.
# Objective
Update Bevy to wgpu 0.15.
## Changelog
- Update to wgpu 0.15, wgpu-hal 0.15.1, and naga 0.11
- Users can now use the [DirectX Shader Compiler](https://github.com/microsoft/DirectXShaderCompiler) (DXC) on Windows with DX12 for faster shader compilation and ShaderModel 6.0+ support (requires `dxcompiler.dll` and `dxil.dll`, which are included in DXC downloads from [here](https://github.com/microsoft/DirectXShaderCompiler/releases/latest))
## Migration Guide
### WGSL Top-Level `let` is now `const`
All top level constants are now declared with `const`, catching up with the wgsl spec.
`let` is no longer allowed at the global scope, only within functions.
```diff
-let SOME_CONSTANT = 12.0;
+const SOME_CONSTANT = 12.0;
```
#### `TextureDescriptor` and `SurfaceConfiguration` now requires a `view_formats` field
The new `view_formats` field in the `TextureDescriptor` is used to specify a list of formats the texture can be re-interpreted to in a texture view. Currently only changing srgb-ness is allowed (ex. `Rgba8Unorm` <=> `Rgba8UnormSrgb`). You should set `view_formats` to `&[]` (empty) unless you have a specific reason not to.
#### The DirectX Shader Compiler (DXC) is now supported on DX12
DXC is now the default shader compiler when using the DX12 backend. DXC is Microsoft's replacement for their legacy FXC compiler, and is faster, less buggy, and allows for modern shader features to be used (ShaderModel 6.0+). DXC requires `dxcompiler.dll` and `dxil.dll` to be available, otherwise it will log a warning and fall back to FXC.
You can get `dxcompiler.dll` and `dxil.dll` by downloading the latest release from [Microsoft's DirectXShaderCompiler github repo](https://github.com/microsoft/DirectXShaderCompiler/releases/latest) and copying them into your project's root directory. These must be included when you distribute your Bevy game/app/etc if you plan on supporting the DX12 backend and are using DXC.
`WgpuSettings` now has a `dx12_shader_compiler` field which can be used to choose between either FXC or DXC (if you pass None for the paths for DXC, it will check for the .dlls in the working directory).
# Objective
- The functions added to utils.wgsl by the prepass assume that mesh_view_bindings are present, which isn't always the case
- Fixes https://github.com/bevyengine/bevy/issues/7353
## Solution
- Move these functions to their own `prepass_utils.wgsl` file
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
# 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`;
# 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>
# 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>
