Commit graph

30 commits

Author SHA1 Message Date
Carter Anderson
ffecb05a0a Replace old renderer with new renderer (#3312)
This makes the [New Bevy Renderer](#2535) the default (and only) renderer. The new renderer isn't _quite_ ready for the final release yet, but I want as many people as possible to start testing it so we can identify bugs and address feedback prior to release.

The examples are all ported over and operational with a few exceptions:

* I removed a good portion of the examples in the `shader` folder. We still have some work to do in order to make these examples possible / ergonomic / worthwhile: #3120 and "high level shader material plugins" are the big ones. This is a temporary measure.
* Temporarily removed the multiple_windows example: doing this properly in the new renderer will require the upcoming "render targets" changes. Same goes for the render_to_texture example.
* Removed z_sort_debug: entity visibility sort info is no longer available in app logic. we could do this on the "render app" side, but i dont consider it a priority.
2021-12-14 03:58:23 +00:00
Robert Swain
2abf5cc618 Clustered forward rendering (#3153)
# Objective

Implement clustered-forward rendering.

## Solution

~~FIXME - in the interest of keeping the merge train moving, I'm submitting this PR now before the description is ready. I want to add in some comments into the code with references for the various bits and pieces and I want to describe some of the key decisions I made here. I'll do that as soon as I can.~~ Anyone reviewing is welcome to add review comments where you want to know more about how something or other works.

* The summary of the technique is that the view frustum is divided into a grid of sub-volumes called clusters, point lights are tested against each of the clusters to see if they would affect that volume within the scene and if so, added to a list of lights affecting that cluster. Then when shading a fragment which is a point on the surface of a mesh within the scene, the point is mapped to a cluster and only the lights affecting that clusters are used in lighting calculations. This brings huge performance and scalability benefits as most of the time lights are placed so that there are not that many that overlap each other in terms of their sphere of influence, but there may be many distinct point lights visible in the scene. Doing all the lighting calculations for all visible lights in the scene for every pixel on the screen quickly becomes a performance limitation. Clustered forward rendering allows us to make an approximate list of lights that affect each pixel, indeed each surface in the scene (as it works along the view z axis too, unlike tiled/forward+).
* WebGL2 is a platform we want to support and it does not support storage buffers. Uniform buffer bindings are limited to a maximum of 16384 bytes per binding. I used bit shifting and masking to pack the cluster light lists and various indices into a uniform buffer and the 16kB limit is very likely the first bottleneck in scaling the number of lights in a scene at the moment if the lights can affect many clusters due to their range or proximity to the camera (there are a lot of clusters close to the camera, which is an area for improvement). We could store the information in textures instead of uniform buffers to remove this bottleneck though I don’t know if there are performance implications to reading from textures instead if uniform buffers.
* Because of the uniform buffer binding size limitations we can support a maximum of 256 lights with the current size of the PointLight struct
* The z-slicing method (i.e. the mapping from view space z to a depth slice which defines the near and far planes of a cluster) is using the Doom 2016 method. I need to add comments with references to this. It’s an exponential function that simplifies well for the purposes of optimising the fragment shader. xy grid divisions are regular in screen space.
* Some optimisation work was done on the allocation of lights to clusters, which involves intersection tests, and for this number of clusters and lights the system has insignificant cost using a fairly naïve algorithm. I think for more lights / finer-grained clusters we could use a BVH, but at some point it would be just much better to use compute shaders and storage buffers.
* Something else to note is that it is absolutely infeasible to use plain cube map point light shadow mapping for many lights. It does not scale in terms of performance nor memory usage. There are some interesting methods I saw discussed in reference material that I will add a link to which render and update shadow maps piece-wise, but they also need compute shaders to work well. Basically for now you need to sacrifice point light shadows for all but a handful of point lights if you don’t want to kill performance. I set the limit to 10 but that’s just what we had from before where 10 was the maximum number of point lights before this PR.
* I added a couple of debug visualisations behind a shader def that were useful for seeing performance impact of light distribution - I should make the debug mode configurable without modifying the shader code. One mode shows the number of lights affecting each cluster by tinting toward red for few lights or green for many lights (maxes out at 16, but not sure that’s a reasonable max). The other shows which cluster the surface at a fragment belongs to by tinting it with a randomish colour. This can help to understand deeper performance issues due to screen space tiles spanning multiple clusters in depth with divergent shader execution times.

Also, there are more things that could be done as improvements, and I will document those somewhere (I'm not sure where will be the best place... in a todo alongside the code, a GitHub issue, somewhere else?) but I think it works well enough and brings significant performance and scalability benefits that it's worth integrating already now and then iterating on.
* Calculate the light’s effective range based on its intensity and physical falloff and either just use this, or take the minimum of the user-supplied range and this. This would avoid unnecessary lighting calculations for clusters that cannot be affected. This would need to take into account HDR tone mapping as in my not-fully-understanding-the-details understanding, the threshold is relative to how bright the scene is.
* Improve the z-slicing to use a larger first slice.
* More gracefully handle the cluster light list uniform buffer binding size limitations by prioritising which lights are included (some heuristic for most significant like closest to the camera, brightest, affecting the most pixels, …)
* Switch to using a texture instead of uniform buffer
* Figure out the / a better story for shadows

I will also probably add an example that demonstrates some of the issues:
* What situations exhaust the space available in the uniform buffers
  * Light range too large making lights affect many clusters and so exhausting the space for the lists of lights that affect clusters
  * Light range set to be too small producing visible artifacts where clusters the light would physically affect are not affected by the light
* Perhaps some performance issues
  * How many lights can be closely packed or affect large portions of the view before performance drops?
2021-12-09 03:08:54 +00:00
Carter Anderson
2e79951659 Shader Imports. Decouple Mesh logic from PBR (#3137)
## Shader Imports

This adds "whole file" shader imports. These come in two flavors:

### Asset Path Imports

```rust
// /assets/shaders/custom.wgsl

#import "shaders/custom_material.wgsl"

[[stage(fragment)]]
fn fragment() -> [[location(0)]] vec4<f32> {
    return get_color();
}
```

```rust
// /assets/shaders/custom_material.wgsl

[[block]]
struct CustomMaterial {
    color: vec4<f32>;
};
[[group(1), binding(0)]]
var<uniform> material: CustomMaterial;
```

### Custom Path Imports

Enables defining custom import paths. These are intended to be used by crates to export shader functionality:

```rust
// bevy_pbr2/src/render/pbr.wgsl

#import bevy_pbr::mesh_view_bind_group
#import bevy_pbr::mesh_bind_group

[[block]]
struct StandardMaterial {
    base_color: vec4<f32>;
    emissive: vec4<f32>;
    perceptual_roughness: f32;
    metallic: f32;
    reflectance: f32;
    flags: u32;
};

/* rest of PBR fragment shader here */
```

```rust
impl Plugin for MeshRenderPlugin {
    fn build(&self, app: &mut bevy_app::App) {
        let mut shaders = app.world.get_resource_mut::<Assets<Shader>>().unwrap();
        shaders.set_untracked(
            MESH_BIND_GROUP_HANDLE,
            Shader::from_wgsl(include_str!("mesh_bind_group.wgsl"))
                .with_import_path("bevy_pbr::mesh_bind_group"),
        );
        shaders.set_untracked(
            MESH_VIEW_BIND_GROUP_HANDLE,
            Shader::from_wgsl(include_str!("mesh_view_bind_group.wgsl"))
                .with_import_path("bevy_pbr::mesh_view_bind_group"),
        );
```

By convention these should use rust-style module paths that start with the crate name. Ultimately we might enforce this convention.

Note that this feature implements _run time_ import resolution. Ultimately we should move the import logic into an asset preprocessor once Bevy gets support for that.

## Decouple Mesh Logic from PBR Logic via MeshRenderPlugin

This breaks out mesh rendering code from PBR material code, which improves the legibility of the code, decouples mesh logic from PBR logic, and opens the door for a future `MaterialPlugin<T: Material>` that handles all of the pipeline setup for arbitrary shader materials.

## Removed `RenderAsset<Shader>` in favor of extracting shaders into RenderPipelineCache

This simplifies the shader import implementation and removes the need to pass around `RenderAssets<Shader>`.

##  RenderCommands are now fallible

This allows us to cleanly handle pipelines+shaders not being ready yet. We can abort a render command early in these cases, preventing bevy from trying to bind group / do draw calls for pipelines that couldn't be bound. This could also be used in the future for things like "components not existing on entities yet". 

# Next Steps

* Investigate using Naga for "partial typed imports" (ex: `#import bevy_pbr::material::StandardMaterial`, which would import only the StandardMaterial struct)
* Implement `MaterialPlugin<T: Material>` for low-boilerplate custom material shaders
* Move shader import logic into the asset preprocessor once bevy gets support for that.

Fixes #3132
2021-11-18 03:45:02 +00:00
Robert Swain
213839f503 Add support for opaque, alpha mask, and alpha blend modes (#3072)
# Objective

Add depth prepass and support for opaque, alpha mask, and alpha blend modes for the 3D PBR target.

## Solution

NOTE: This is based on top of #2861 frustum culling. Just lining it up to keep @cart loaded with the review train. 🚂 

There are a lot of important details here. Big thanks to @cwfitzgerald of wgpu, naga, and rend3 fame for explaining how to do it properly!

* An `AlphaMode` component is added that defines whether a material should be considered opaque, an alpha mask (with a cutoff value that defaults to 0.5, the same as glTF), or transparent and should be alpha blended
* Two depth prepasses are added:
  * Opaque does a plain vertex stage
  * Alpha mask does the vertex stage but also a fragment stage that samples the colour for the fragment and discards if its alpha value is below the cutoff value
  * Both are sorted front to back, not that it matters for these passes. (Maybe there should be a way to skip sorting?)
* Three main passes are added:
  * Opaque and alpha mask passes use a depth comparison function of Equal such that only the geometry that was closest is processed further, due to early-z testing
  * The transparent pass uses the Greater depth comparison function so that only transparent objects that are closer than anything opaque are rendered
  * The opaque fragment shading is as before except that alpha is explicitly set to 1.0
  * Alpha mask fragment shading sets the alpha value to 1.0 if it is equal to or above the cutoff, as defined by glTF
  * Opaque and alpha mask are sorted front to back (again not that it matters as we will skip anything that is not equal... maybe sorting is no longer needed here?)
  * Transparent is sorted back to front. Transparent fragment shading uses the alpha blending over operator

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-11-16 03:03:27 +00:00
Carter Anderson
9a4cc42b38 EntityRenderCommand and PhaseItemRenderCommand (#3111)
Adds new `EntityRenderCommand`, `EntityPhaseItem`, and `CachedPipelinePhaseItem` traits to make it possible to reuse RenderCommands across phases. This should be helpful for features like #3072 . It also makes the trait impls slightly less generic-ey in the common cases.

This also fixes the custom shader examples to account for the recent Frustum Culling and MSAA changes (the UX for these things will be improved later).
2021-11-12 22:27:17 +00:00
Robert Swain
bc5916cce7 Frustum culling (#2861)
# Objective

Implement frustum culling for much better performance on more complex scenes. With the Amazon Lumberyard Bistro scene, I was getting roughly 15fps without frustum culling and 60+fps with frustum culling on a MacBook Pro 16 with i9 9980HK 8c/16t CPU and Radeon Pro 5500M.

macOS does weird things with vsync so even though vsync was off, it really looked like sometimes other applications or the desktop window compositor were interfering, but the difference could be even more as I even saw up to 90+fps sometimes.

## Solution

- Until the https://github.com/bevyengine/rfcs/pull/12 RFC is completed, I wanted to implement at least some of the bounding volume functionality we needed to be able to unblock a bunch of rendering features and optimisations such as frustum culling, fitting the directional light orthographic projection to the relevant meshes in the view, clustered forward rendering, etc.
- I have added `Aabb`, `Frustum`, and `Sphere` types with only the necessary intersection tests for the algorithms used. I also added `CubemapFrusta` which contains a `[Frustum; 6]` and can be used by cube maps such as environment maps, and point light shadow maps.
  - I did do a bit of benchmarking and optimisation on the intersection tests. I compared the [rafx parallel-comparison bitmask approach](c91bd5fcfd/rafx-visibility/src/geometry/frustum.rs (L64-L92)) with a naïve loop that has an early-out in case of a bounding volume being outside of any one of the `Frustum` planes and found them to be very similar, so I chose the simpler and more readable option. I also compared using Vec3 and Vec3A and it turned out that promoting Vec3s to Vec3A improved performance of the culling significantly due to Vec3A operations using SIMD optimisations where Vec3 uses plain scalar operations.
- When loading glTF models, the vertex attribute accessors generally store the minimum and maximum values, which allows for adding AABBs to meshes loaded from glTF for free.
- For meshes without an AABB (`PbrBundle` deliberately does not have an AABB by default), a system is executed that scans over the vertex positions to find the minimum and maximum values along each axis. This is used to construct the AABB.
- The `Frustum::intersects_obb` and `Sphere::insersects_obb` algorithm is from Foundations of Game Engine Development 2: Rendering by Eric Lengyel. There is no OBB type, yet, rather an AABB and the model matrix are passed in as arguments. This calculates a 'relative radius' of the AABB with respect to the plane normal (the plane normal in the Sphere case being something I came up with as the direction pointing from the centre of the sphere to the centre of the AABB) such that it can then do a sphere-sphere intersection test in practice.
- `RenderLayers` were copied over from the current renderer.
- `VisibleEntities` was copied over from the current renderer and a `CubemapVisibleEntities` was added to support `PointLight`s for now. `VisibleEntities` are added to views (cameras and lights) and contain a `Vec<Entity>` that is populated by culling/visibility systems that run in PostUpdate of the app world, and are iterated over in the render world for, for example, queuing up meshes to be drawn by lights for shadow maps and the main pass for cameras.
- `Visibility` and `ComputedVisibility` components were added. The `Visibility` component is user-facing so that, for example, the entity can be marked as not visible in an editor. `ComputedVisibility` on the other hand is the result of the culling/visibility systems and takes `Visibility` into account. So if an entity is marked as not being visible in its `Visibility` component, that will skip culling/visibility intersection tests and just mark the `ComputedVisibility` as false.
- The `ComputedVisibility` is used to decide which meshes to extract.
- I had to add a way to get the far plane from the `CameraProjection` in order to define an explicit far frustum plane for culling. This should perhaps be optional as it is not always desired and in that case, testing 5 planes instead of 6 is a performance win.

I think that's about all. I discussed some of the design with @cart on Discord already so hopefully it's not too far from being mergeable. It works well at least. 😄
2021-11-07 21:45:52 +00:00
Robert Swain
09706cdb2a Support for normal maps including from glTF models (#2741)
# Objective

- Support tangent vertex attributes, and normal maps
- Support loading these from glTF models

## Solution

- Make two pipelines in both the shadow and pbr passes, one for without normal maps, one for with normal maps
- Select the correct pipeline to bind based on the presence of the normal map texture
- Share the vertex attribute layout between shadow and pbr passes
- Refactored pbr.wgsl to share a bunch of common code between the normal map and non-normal map entry points. I tried to do this in a way that will allow custom shader reuse.

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-11-04 21:47:57 +00:00
Carter Anderson
c5af1335eb Add MSAA to new renderer (#3042)
Adds support for MSAA to the new renderer. This is done using the new [pipeline specialization](#3031) support to specialize on sample count. This is an alternative implementation to #2541 that cuts out the need for complicated render graph edge management by moving the relevant target information into View entities. This reuses @superdump's clever MSAA bitflag range code from #2541.

Note that wgpu currently only supports 1 or 4 samples due to those being the values supported by WebGPU. However they do plan on exposing ways to [enable/query for natively supported sample counts](https://github.com/gfx-rs/wgpu/issues/1832). When this happens we should integrate
2021-10-29 05:37:43 +00:00
Mariusz Kryński
dacc9d03a7 Add support for IndexFormat::Uint16 (#2990)
# Objective

while testing wgpu/WebGL on mobile GPU I've noticed bevy always forces vertex index format to 32bit (and ignores mesh settings). 

## Solution

the solution is to pass proper vertex index format in GpuIndexInfo to render_pass
2021-10-28 22:53:22 +00:00
Carter Anderson
015617a774 Pipeline Specialization, Shader Assets, and Shader Preprocessing (#3031)
## New Features
This adds the following to the new renderer:

* **Shader Assets**
  * Shaders are assets again! Users no longer need to call `include_str!` for their shaders
  * Shader hot-reloading
* **Shader Defs / Shader Preprocessing**
  * Shaders now support `# ifdef NAME`, `# ifndef NAME`, and `# endif` preprocessor directives
* **Bevy RenderPipelineDescriptor and RenderPipelineCache**
  * Bevy now provides its own `RenderPipelineDescriptor` and the wgpu version is now exported as `RawRenderPipelineDescriptor`. This allows users to define pipelines with `Handle<Shader>` instead of needing to manually compile and reference `ShaderModules`, enables passing in shader defs to configure the shader preprocessor, makes hot reloading possible (because the descriptor can be owned and used to create new pipelines when a shader changes), and opens the doors to pipeline specialization.
  * The `RenderPipelineCache` now handles compiling and re-compiling Bevy RenderPipelineDescriptors. It has internal PipelineLayout and ShaderModule caches. Users receive a `CachedPipelineId`, which can be used to look up the actual `&RenderPipeline` during rendering. 
* **Pipeline Specialization**
  * This enables defining per-entity-configurable pipelines that specialize on arbitrary custom keys. In practice this will involve specializing based on things like MSAA values, Shader Defs, Bind Group existence, and Vertex Layouts.
  * Adds a `SpecializedPipeline` trait and `SpecializedPipelines<MyPipeline>` resource. This is a simple layer that generates Bevy RenderPipelineDescriptors based on a custom key defined for the pipeline.
  * Specialized pipelines are also hot-reloadable.
  * This was the result of experimentation with two different approaches:
    1. **"generic immediate mode multi-key hash pipeline specialization"**
      * breaks up the pipeline into multiple "identities" (the core pipeline definition, shader defs, mesh layout, bind group layout). each of these identities has its own key. looking up / compiling a specific version of a pipeline requires composing all of these keys together
      * the benefit of this approach is that it works for all pipelines / the pipeline is fully identified by the keys. the multiple keys allow pre-hashing parts of the pipeline identity where possible (ex: pre compute the mesh identity for all meshes)
      * the downside is that any per-entity data that informs the values of these keys could require expensive re-hashes. computing each key for each sprite tanked bevymark performance (sprites don't actually need this level of specialization yet ... but things like pbr and future sprite scenarios might). 
      * this is the approach rafx used last time i checked
    2. **"custom key specialization"**
      * Pipelines by default are not specialized
      * Pipelines that need specialization implement a SpecializedPipeline trait with a custom key associated type
      * This allows specialization keys to encode exactly the amount of information required (instead of needing to be a combined hash of the entire pipeline). Generally this should fit in a small number of bytes. Per-entity specialization barely registers anymore on things like bevymark. It also makes things like "shader defs" way cheaper to hash because we can use context specific bitflags instead of strings.
      * Despite the extra trait, it actually generally makes pipeline definitions + lookups simpler: managing multiple keys (and making the appropriate calls to manage these keys) was way more complicated.
  * I opted for custom key specialization. It performs better generally and in my opinion is better UX. Fortunately the way this is implemented also allows for custom caches as this all builds on a common abstraction: the RenderPipelineCache. The built in custom key trait is just a simple / pre-defined way to interact with the cache 

## Callouts

* The SpecializedPipeline trait makes it easy to inherit pipeline configuration in custom pipelines. The changes to `custom_shader_pipelined` and the new `shader_defs_pipelined` example illustrate how much simpler it is to define custom pipelines based on the PbrPipeline.
* The shader preprocessor is currently pretty naive (it just uses regexes to process each line). Ultimately we might want to build a more custom parser for more performance + better error handling, but for now I'm happy to optimize for "easy to implement and understand". 

## Next Steps

* Port compute pipelines to the new system
* Add more preprocessor directives (else, elif, import)
* More flexible vertex attribute specialization / enable cheaply specializing on specific mesh vertex layouts
2021-10-28 19:07:47 +00:00
Carter Anderson
43e8a156fb Upgrade to wgpu 0.11 (#2933)
Upgrades both the old and new renderer to wgpu 0.11 (and naga 0.7). This builds on @zicklag's work here #2556.

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-10-08 19:55:24 +00:00
Robert Swain
0eb11df394 Apply labels to wgpu resources for improved debugging/profiling (#2912)
# Objective

$subj. All of these names show up in external tools when debugging/profiling frames, which is super useful.
2021-10-03 19:04:37 +00:00
Carter Anderson
08969a24b8 Modular Rendering (#2831)
This changes how render logic is composed to make it much more modular. Previously, all extraction logic was centralized for a given "type" of rendered thing. For example, we extracted meshes into a vector of ExtractedMesh, which contained the mesh and material asset handles, the transform, etc. We looked up bindings for "drawn things" using their index in the `Vec<ExtractedMesh>`. This worked fine for built in rendering, but made it hard to reuse logic for "custom" rendering. It also prevented us from reusing things like "extracted transforms" across contexts.

To make rendering more modular, I made a number of changes:

* Entities now drive rendering:
  * We extract "render components" from "app components" and store them _on_ entities. No more centralized uber lists! We now have true "ECS-driven rendering"
  * To make this perform well, I implemented #2673 in upstream Bevy for fast batch insertions into specific entities. This was merged into the `pipelined-rendering` branch here: #2815
* Reworked the `Draw` abstraction:
  * Generic `PhaseItems`: each draw phase can define its own type of "rendered thing", which can define its own "sort key"
  * Ported the 2d, 3d, and shadow phases to the new PhaseItem impl (currently Transparent2d, Transparent3d, and Shadow PhaseItems)
  * `Draw` trait and and `DrawFunctions` are now generic on PhaseItem
  * Modular / Ergonomic `DrawFunctions` via `RenderCommands`
    * RenderCommand is a trait that runs an ECS query and produces one or more RenderPass calls. Types implementing this trait can be composed to create a final DrawFunction. For example the DrawPbr DrawFunction is created from the following DrawCommand tuple. Const generics are used to set specific bind group locations:
        ```rust
         pub type DrawPbr = (
            SetPbrPipeline,
            SetMeshViewBindGroup<0>,
            SetStandardMaterialBindGroup<1>,
            SetTransformBindGroup<2>,
            DrawMesh,
        );
        ```
    * The new `custom_shader_pipelined` example illustrates how the commands above can be reused to create a custom draw function:
       ```rust
       type DrawCustom = (
           SetCustomMaterialPipeline,
           SetMeshViewBindGroup<0>,
           SetTransformBindGroup<2>,
           DrawMesh,
       );
       ``` 
* ExtractComponentPlugin and UniformComponentPlugin:
  * Simple, standardized ways to easily extract individual components and write them to GPU buffers
* Ported PBR and Sprite rendering to the new primitives above.
* Removed staging buffer from UniformVec in favor of direct Queue usage
  * Makes UniformVec much easier to use and more ergonomic. Completely removes the need for custom render graph nodes in these contexts (see the PbrNode and view Node removals and the much simpler call patterns in the relevant Prepare systems).
* Added a many_cubes_pipelined example to benchmark baseline 3d rendering performance and ensure there were no major regressions during this port. Avoiding regressions was challenging given that the old approach of extracting into centralized vectors is basically the "optimal" approach. However thanks to a various ECS optimizations and render logic rephrasing, we pretty much break even on this benchmark!
* Lifetimeless SystemParams: this will be a bit divisive, but as we continue to embrace "trait driven systems" (ex: ExtractComponentPlugin, UniformComponentPlugin, DrawCommand), the ergonomics of `(Query<'static, 'static, (&'static A, &'static B, &'static)>, Res<'static, C>)` were getting very hard to bear. As a compromise, I added "static type aliases" for the relevant SystemParams. The previous example can now be expressed like this: `(SQuery<(Read<A>, Read<B>)>, SRes<C>)`. If anyone has better ideas / conflicting opinions, please let me know!
* RunSystem trait: a way to define Systems via a trait with a SystemParam associated type. This is used to implement the various plugins mentioned above. I also added SystemParamItem and QueryItem type aliases to make "trait stye" ecs interactions nicer on the eyes (and fingers).
* RenderAsset retrying: ensures that render assets are only created when they are "ready" and allows us to create bind groups directly inside render assets (which significantly simplified the StandardMaterial code). I think ultimately we should swap this out on "asset dependency" events to wait for dependencies to load, but this will require significant asset system changes.
* Updated some built in shaders to account for missing MeshUniform fields
2021-09-23 06:16:11 +00:00
Robert Swain
045f324e97 Use the infinite reverse right-handed perspective projection (#2543)
# Objective

Forward perspective projections have poor floating point precision distribution over the depth range. Reverse projections fair much better, and instead of having to have a far plane, with the reverse projection, using an infinite far plane is not a problem. The infinite reverse perspective projection has become the industry standard. The renderer rework is a great time to migrate to it.

## Solution

All perspective projections, including point lights, have been moved to using `glam::Mat4::perspective_infinite_reverse_rh()` and so have no far plane. As various depth textures are shared between orthographic and perspective projections, a quirk of this PR is that the near and far planes of the orthographic projection are swapped when the Mat4 is computed. This has no impact on 2D/3D orthographic projection usage, and provides consistency in shaders, texture clear values, etc. throughout the codebase.

## Known issues

For some reason, when looking along -Z, all geometry is black. The camera can be translated up/down / strafed left/right and geometry will still be black. Moving forward/backward or rotating the camera away from looking exactly along -Z causes everything to work as expected.

I have tried to debug this issue but both in macOS and Windows I get crashes when doing pixel debugging. If anyone could reproduce this and debug it I would be very grateful. Otherwise I will have to try to debug it further without pixel debugging, though the projections and such all looked fine to me.
2021-08-27 20:15:09 +00:00
Robert Swain
dd32cd029d Pipelined separate shadow vertex shader (#2727)
# Objective

- Avoid unnecessary work in the vertex shader of the numerous shadow passes
- Have the natural order of bind groups in the pbr shader: view, material, mesh

## Solution

- Separate out the vertex stage of pbr.wgsl into depth.wgsl
- Remove the unnecessary calculation of uv and normal, as well as removing the unnecessary vertex inputs and outputs
- Use the depth.wgsl for shadow passes
- Reorder the bind groups in pbr.wgsl and PbrShaders to be 0 - view, 1 - material, 2 - mesh in decreasing order of rebind frequency
2021-08-25 20:10:43 +00:00
Robert Swain
f4aa3284a8 bevy_pbr2: Add support for not casting/receiving shadows (#2726)
# Objective

Allow marking meshes as not casting / receiving shadows.

## Solution

- Added `NotShadowCaster` and `NotShadowReceiver` zero-sized type components.
- Extract these components into `bool`s in `ExtractedMesh`
- Only generate `DrawShadowMesh` `Drawable`s for meshes _without_ `NotShadowCaster`
- Add a `u32` bit `flags` member to `MeshUniform` with one flag indicating whether the mesh is a shadow receiver
- If a mesh does _not_ have the `NotShadowReceiver` component, then it is a shadow receiver, and so the bit in the `MeshUniform` is set, otherwise it is not set.
- Added an example illustrating the functionality.

NOTE: I wanted to have the default state of a mesh as being a shadow caster and shadow receiver, hence the `Not*` components. However, I am on the fence about this. I don't want to have a negative performance impact, nor have people wondering why their custom meshes don't have shadows because they forgot to add `ShadowCaster` and `ShadowReceiver` components, but I also really don't like the double negatives the `Not*` approach incurs. What do you think?

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-08-25 19:44:20 +00:00
Carter Anderson
7b336fd779 fix nightly clippy lints (#2568)
Fix new nightly clippy lints on `pipelined-rendering`
2021-07-30 03:17:27 +00:00
Carter Anderson
3ec6b3f9a0 move bevy_core_pipeline to its own plugin (#2552)
This decouples the opinionated "core pipeline" from the new (less opinionated) bevy_render crate. The "core pipeline" is intended to be used by crates like bevy_sprites, bevy_pbr, bevy_ui, and 3rd party crates that extends core rendering functionality.
2021-07-28 21:29:32 +00:00
Robert Swain
326b20643f Directional light and shadow (#6)
Directional light and shadow
2021-07-24 16:43:37 -07:00
Carter Anderson
ac6b27925e fix clippy 2021-07-24 16:43:37 -07:00
Jonas Matser
4099ef6aa2 Omnilight shadow map wgsl (#15) 2021-07-24 16:43:37 -07:00
Robert Swain
858065ef8d Do not queue sprites/meshes if there are no views (#13)
* bevy_sprite2/_pbr2: Do not queue sprites/meshes if there are no views
2021-07-24 16:43:37 -07:00
John
5d0655f84c Fixed issue where transform buffer wasn't creating new bindings on resize. (#7) 2021-07-24 16:43:37 -07:00
Robert Swain
3f70f92bff wgsl PBR fixes (#12)
bevy_pbr2: Fix light uniforms
2021-07-24 16:43:37 -07:00
Carter Anderson
61c8475069 Begin WGSL port (sprites work, pbr lights are broken) 2021-07-24 16:43:37 -07:00
Robert Swain
b1a91a823f bevy_pbr2: Add support for most of the StandardMaterial textures (#4)
* bevy_pbr2: Add support for most of the StandardMaterial textures

Normal maps are not included here as they require tangents in a vertex attribute.

* bevy_pbr2: Ensure RenderCommandQueue is ready for PbrShaders init

* texture_pipelined: Add a light to the scene so we can see stuff

* WIP bevy_pbr2: back to front sorting hack

* bevy_pbr2: Uniform control flow for texture sampling in pbr.frag

From 'fintelia' on the Bevy Render Rework Round 2 discussion:

"My understanding is that GPUs these days never use the "execute both branches
and select the result" strategy. Rather, what they do is evaluate the branch
condition on all threads of a warp, and jump over it if all of them evaluate to
false. If even a single thread needs to execute the if statement body, however,
then the remaining threads are paused until that is completed."

* bevy_pbr2: Simplify texture and sampler names

The StandardMaterial_ prefix is no longer needed

* bevy_pbr2: Match default 'AmbientColor' of current bevy_pbr for now

* bevy_pbr2: Convert from non-linear to linear sRGB for the color uniform

* bevy_pbr2: Add pbr_pipelined example

* Fix view vector in pbr frag to work in ortho

* bevy_pbr2: Use a 90 degree y fov and light range projection for lights

* bevy_pbr2: Add AmbientLight resource

* bevy_pbr2: Convert PointLight color to linear sRGB for use in fragment shader

* bevy_pbr2: pbr.frag: Rename PointLight.projection to view_projection

The uniform contains the view_projection matrix so this was incorrect.

* bevy_pbr2: PointLight is an OmniLight as it has a radius

* bevy_pbr2: Factoring out duplicated code

* bevy_pbr2: Implement RenderAsset for StandardMaterial

* Remove unnecessary texture and sampler clones

* fix comment formatting

* remove redundant Buffer:from

* Don't extract meshes when their material textures aren't ready

* make missing textures in the queue step an error

Co-authored-by: Aevyrie <aevyrie@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-07-24 16:43:37 -07:00
Carter Anderson
25de2d1819 Port Mesh to RenderAsset, add Slab and FrameSlabMap garbage collection for Bind Groups 2021-07-24 16:43:37 -07:00
Carter Anderson
13ca00178a bevy_render now uses wgpu directly 2021-07-24 16:43:37 -07:00
Robert Swain
01116b1fdb StandardMaterial flat values (#3)
StandardMaterial flat values
2021-07-24 16:43:37 -07:00
Carter Anderson
3400fb4e61 SubGraphs, Views, Shadows, and more 2021-07-24 16:43:37 -07:00