Commit graph

92 commits

Author SHA1 Message Date
Charles
6c2f78f449 Validate vertex attribute format on insert (#5259)
# Objective

- Validate the format of the values with the expected attribute format.
- Currently, if you pass the wrong format, it will crash somewhere unrelated with a very cryptic error message, so it's really hard to debug for beginners.

## Solution

- Compare the format and panic when unexpected format is passed

## Note

- I used a separate `error!()` for a human friendly message because the panic message is very noisy and hard to parse for beginners. I don't mind changing this to only a panic if people prefer that.
- This could potentially be something that runs only in debug mode, but I don't think inserting attributes is done often enough for this to be an issue.


Co-authored-by: Charles <IceSentry@users.noreply.github.com>
2022-07-11 14:11:31 +00:00
Kornel
fda1fee1bb Use collect to build mesh attributes (#5255)
Small optimization. `.collect()` from arrays generates very nice code without reallocations: https://rust.godbolt.org/z/6E6c595bq

Co-authored-by: Kornel <kornel@geekhood.net>
2022-07-11 14:11:30 +00:00
Robin KAY
e6faf993b0 Add support for removing attributes from meshes. (#5254)
# Objective

Support removing attributes from meshes. For an example use case, meshes created using the bevy::predule::shape types or loaded from external files may have attributes that are not needed for the materials they will be rendered with.

This was extracted from PR #5222.

## Solution

Implement Mesh::remove_attribute().
2022-07-08 21:18:32 +00:00
CGMossa
33f9b3940d Updated glam to 0.21. (#5142)
Removed `const_vec2`/`const_vec3`
and replaced with equivalent `.from_array`.

# Objective

Fixes #5112 

## Solution

- `encase` needs to update to `glam` as well. See teoxoy/encase#4 on progress on that. 
- `hexasphere` also needs to be updated, see OptimisticPeach/hexasphere#12.
2022-07-03 19:55:33 +00:00
Rob Parrett
5e1756954f Derive default for enums where possible (#5158)
# Objective

Fixes #5153

## Solution

Search for all enums and manually check if they have default impls that can use this new derive.

By my reckoning:

| enum | num |
|-|-|
| total | 159 |
| has default impl | 29 |
| default is unit variant | 23 |
2022-07-01 03:42:15 +00:00
Ben Reeves
32cd9899c8 bevy_render: Add attributes and attributes_mut methods to Mesh. (#3927)
# Use Case

Seems generally useful, but specifically motivated by my work on the [`bevy_datasize`](https://github.com/BGR360/bevy_datasize) crate.

For that project, I'm implementing "heap size estimators" for all of the Bevy internal types. To do this accurately for `Mesh`, I need to get the lengths of all of the mesh's attribute vectors.

Currently, in order to accomplish this, I am doing the following:

* Checking all of the attributes that are mentioned in the `Mesh` class ([see here](0531ec2d02/src/builtins/render/mesh.rs (L46-L54)))

* Providing the user with an option to configure additional attributes to check ([see here](0531ec2d02/src/config.rs (L7-L21)))

This is both overly complicated and a bit wasteful (since I have to check every attribute name that I know about in case there are attributes set for it).

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-06-15 06:29:52 +00:00
James Liu
f2b545049c Implement FusedIterator for eligible Iterator types (#4942)
# Objective
Most of our `Iterator` impls satisfy the requirements of `std::iter::FusedIterator`, which has internal specialization that optimizes `Interator::fuse`. The std lib iterator combinators do have a few that rely on `fuse`, so this could optimize those use cases. I don't think we're using any of them in the engine itself, but beyond a light increase in compile time, it doesn't hurt to implement the trait.

## Solution
Implement the trait for all eligible iterators in first party crates. Also add a missing `ExactSizeIterator` on an iterator that could use it.
2022-06-09 03:19:31 +00:00
Robert Swain
bdef86ea6e Generate vertex tangents using mikktspace (#3872)
# Objective

Models can be produced that do not have vertex tangents but do have normal map textures. The tangents can be generated. There is a way that the vertex tangents can be generated to be exactly invertible to avoid introducing error when recreating the normals in the fragment shader.

## Solution

- After attempts to get https://github.com/gltf-rs/mikktspace to integrate simple glam changes and version bumps, and releases of that crate taking weeks / not being made (no offense intended to the authors/maintainers, bevy just has its own timelines and needs to take care of) it was decided to fork that repository. The following steps were taken:
  - mikktspace was forked to https://github.com/bevyengine/mikktspace in order to preserve the repository's history in case the original is ever taken down
  - The README in that repo was edited to add a note stating from where the repository was forked and explaining why
  - The repo was locked for changes as its only purpose is historical
  - The repo was integrated into the bevy repo using `git subtree add --prefix crates/bevy_mikktspace git@github.com:bevyengine/mikktspace.git master`
  - In `bevy_mikktspace`:
    - The travis configuration was removed
    - `cargo fmt` was run
    - The `Cargo.toml` was conformed to bevy's (just adding bevy to the keywords, changing the homepage and repository, changing the version to 0.7.0-dev - importantly the license is exactly the same)
    - Remove the features, remove `nalgebra` entirely, only use `glam`, suppress clippy.
      - This was necessary because our CI runs clippy with `--all-features` and the `nalgebra` and `glam` features are mutually exclusive, plus I don't want to modify this highly numerically-sensitive code just to appease clippy and diverge even more from upstream.
- Rebase https://github.com/bevyengine/bevy/pull/1795
  - @jakobhellermann said it was fine to copy and paste but it ended up being almost exactly the same with just a couple of adjustments when validating correctness so I decided to actually rebase it and then build on top of it.
- Use the exact same fragment shader code to ensure correct normal mapping.
- Tested with both https://github.com/KhronosGroup/glTF-Sample-Models/tree/master/2.0/NormalTangentMirrorTest which has vertex tangents and https://github.com/KhronosGroup/glTF-Sample-Models/tree/master/2.0/NormalTangentTest which requires vertex tangent generation

Co-authored-by: alteous <alteous@outlook.com>
2022-05-31 22:53:54 +00:00
Félix Lescaudey de Maneville
f000c2b951 Clippy improvements (#4665)
# Objective

Follow up to my previous MR #3718 to add new clippy warnings to bevy:

- [x] [~~option_if_let_else~~](https://rust-lang.github.io/rust-clippy/master/#option_if_let_else) (reverted)
- [x] [redundant_else](https://rust-lang.github.io/rust-clippy/master/#redundant_else)
- [x] [match_same_arms](https://rust-lang.github.io/rust-clippy/master/#match_same_arms)
- [x] [semicolon_if_nothing_returned](https://rust-lang.github.io/rust-clippy/master/#semicolon_if_nothing_returned)
- [x] [explicit_iter_loop](https://rust-lang.github.io/rust-clippy/master/#explicit_iter_loop)
- [x] [map_flatten](https://rust-lang.github.io/rust-clippy/master/#map_flatten)

There is one commit per clippy warning, and the matching flags are added to the CI execution.

To test the CI execution you may run `cargo run -p ci -- clippy` at the root.

I choose the add the flags in the `ci` tool crate to avoid having them in every `lib.rs` but I guess it could become an issue with suprise warnings coming up after a commit/push


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-05-31 01:38:07 +00:00
Joe Ardent
96078c76eb Make accessors for mesh vertices and indices public. (#3906)
# Objective

Make it easy to get position and index data from Meshes.

## Solution

It was previously possible to get the mesh data by manually matching on `Mesh::VertexAttributeValues` and `Mesh::Indices`as in the bodies of these two methods (`VertexAttributeValues::as_float3(&self)` and `Indices::iter(&self)`), but that's needless duplication that making these methods `pub` fixes.
2022-05-09 13:19:33 +00:00
Dusty DeWeese
82d849d3dc Add support for vertex colors (#4528)
# Objective

Add support for vertex colors

## Solution

This change is modeled after how vertex tangents are handled, so the shader is conditionally compiled with vertex color support if the mesh has the corresponding attribute set.

Vertex colors are multiplied by the base color. I'm not sure if this is the best for all cases, but may be useful for modifying vertex colors without creating a new mesh.

I chose `VertexFormat::Float32x4`, but I'd prefer 16-bit floats if/when support is added.

## Changelog

### Added
- Vertex colors can be specified using the `Mesh::ATTRIBUTE_COLOR` mesh attribute.
2022-05-05 00:46:32 +00:00
Rob Parrett
f8e0fc190a Add RegularPolygon and Circle meshes (#3730)
# Objective

Bevy users often want to create circles and other simple shapes.

All the machinery is in place to accomplish this, and there are external crates that help. But when writing code for e.g. a new bevy example, it's not really possible to draw a circle without bringing in a new asset, writing a bunch of scary looking mesh code, or adding a dependency.

In particular, this PR was inspired by this interaction in another PR: https://github.com/bevyengine/bevy/pull/3721#issuecomment-1016774535

## Solution

This PR adds `shape::RegularPolygon` and `shape::Circle` (which is just a `RegularPolygon` that defaults to a large number of sides)

## Discussion

There's a lot of ongoing discussion about shapes in <https://github.com/bevyengine/rfcs/pull/12> and at least one other lingering shape PR (although it seems incomplete).

That RFC currently includes `RegularPolygon` and `Circle` shapes, so I don't think that having working mesh generation code in the engine for those shapes would add much burden to an author of an implementation.

But if we'd prefer not to add additional shapes until after that's sorted out, I'm happy to close this for now.

## Alternatives for users

For any users stumbling on this issue, here are some plugins that will help if you need more shapes.

https://github.com/Nilirad/bevy_prototype_lyon
https://github.com/johanhelsing/bevy_smud
https://github.com/Weasy666/bevy_svg
https://github.com/redpandamonium/bevy_more_shapes
https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline
2022-05-05 00:03:47 +00:00
bjorn3
ddce22b614 Decouple some dependencies (#3886)
# Objective

Reduce from scratch build time.

## Solution

Reduce the size of the critical path by removing dependencies between crates where not necessary. For `cargo check --no-default-features` this reduced build time from ~51s to ~45s. For some commits I am not completely sure if the tradeoff between build time reduction and convenience caused by the commit is acceptable. If not, I can drop them.
2022-04-27 19:08:11 +00:00
Rob Parrett
dafd7a14c9 Fix torus normals (#4520)
# Objective

Fix wonky torus normals.

## Solution

I attempted this previously in #3549, but it looks like I botched it. It seems like I mixed up the y/z axes. Somehow, the result looked okay from that particular camera angle.

This video shows toruses generated with
- [left, orange] original torus mesh code
- [middle, pink] PR 3549
- [right, purple] This PR

https://user-images.githubusercontent.com/200550/164093183-58a7647c-b436-4512-99cd-cf3b705cefb0.mov
2022-04-26 18:42:43 +00:00
devil ira
48ac955afd Fix loading non-TriangleList meshes without normals in gltf loader (#4376)
# Objective
Make it so that loading in a mesh without normals that is not a `TriangleList` succeeds.

## Solution
Flat normals can only be calculated on a mesh made of triangles.
Check whether the mesh is a `TriangleList` before trying to compute missing normals.

## Additional changes
The panic condition in `duplicate_vertices` did not make sense to me. I moved it to `compute_flat_normals` where the algorithm would produce incorrect results if the mesh is not a `TriangleList`.

Co-authored-by: devil-ira <justthecooldude@gmail.com>
2022-03-31 20:43:01 +00:00
James Liu
31bd4ecbbc Mesh Skinning. Attempt #3 (#4238)
# Objective
Load skeletal weights and indices from GLTF files. Animate meshes.

## Solution
 - Load skeletal weights and indices from GLTF files.
 - Added `SkinnedMesh` component and ` SkinnedMeshInverseBindPose` asset
 - Added `extract_skinned_meshes` to extract joint matrices.
 - Added queue phase systems for enqueuing the buffer writes.

Some notes:

 -  This ports part of # #2359 to the current main.
 -  This generates new `BufferVec`s and bind groups every frame. The expectation here is that the number of `Query::get` calls during extract is probably going to be the stronger bottleneck, with up to 256 calls per skinned mesh. Until that is optimized, caching buffers and bind groups is probably a non-concern.
 - Unfortunately, due to the uniform size requirements, this means a 16KB buffer is allocated for every skinned mesh every frame. There's probably a few ways to get around this, but most of them require either compute shaders or storage buffers, which are both incompatible with WebGL2.

Co-authored-by: james7132 <contact@jamessliu.com>
Co-authored-by: François <mockersf@gmail.com>
Co-authored-by: James Liu <contact@jamessliu.com>
2022-03-29 18:31:13 +00:00
Carter Anderson
e369a8ad51 Mesh vertex buffer layouts (#3959)
This PR makes a number of changes to how meshes and vertex attributes are handled, which the goal of enabling easy and flexible custom vertex attributes:
* Reworks the `Mesh` type to use the newly added `VertexAttribute` internally
  * `VertexAttribute` defines the name, a unique `VertexAttributeId`, and a `VertexFormat`
  *  `VertexAttributeId` is used to produce consistent sort orders for vertex buffer generation, replacing the more expensive and often surprising "name based sorting"  
  * Meshes can be used to generate a `MeshVertexBufferLayout`, which defines the layout of the gpu buffer produced by the mesh. `MeshVertexBufferLayouts` can then be used to generate actual `VertexBufferLayouts` according to the requirements of a specific pipeline. This decoupling of "mesh layout" vs "pipeline vertex buffer layout" is what enables custom attributes. We don't need to standardize _mesh layouts_ or contort meshes to meet the needs of a specific pipeline. As long as the mesh has what the pipeline needs, it will work transparently. 
* Mesh-based pipelines now specialize on `&MeshVertexBufferLayout` via the new `SpecializedMeshPipeline` trait (which behaves like `SpecializedPipeline`, but adds `&MeshVertexBufferLayout`). The integrity of the pipeline cache is maintained because the `MeshVertexBufferLayout` is treated as part of the key (which is fully abstracted from implementers of the trait ... no need to add any additional info to the specialization key).    
* Hashing `MeshVertexBufferLayout` is too expensive to do for every entity, every frame. To make this scalable, I added a generalized "pre-hashing" solution to `bevy_utils`: `Hashed<T>` keys and `PreHashMap<K, V>` (which uses `Hashed<T>` internally) . Why didn't I just do the quick and dirty in-place "pre-compute hash and use that u64 as a key in a hashmap" that we've done in the past? Because its wrong! Hashes by themselves aren't enough because two different values can produce the same hash. Re-hashing a hash is even worse! I decided to build a generalized solution because this pattern has come up in the past and we've chosen to do the wrong thing. Now we can do the right thing! This did unfortunately require pulling in `hashbrown` and using that in `bevy_utils`, because avoiding re-hashes requires the `raw_entry_mut` api, which isn't stabilized yet (and may never be ... `entry_ref` has favor now, but also isn't available yet). If std's HashMap ever provides the tools we need, we can move back to that. Note that adding `hashbrown` doesn't increase our dependency count because it was already in our tree. I will probably break these changes out into their own PR.
* Specializing on `MeshVertexBufferLayout` has one non-obvious behavior: it can produce identical pipelines for two different MeshVertexBufferLayouts. To optimize the number of active pipelines / reduce re-binds while drawing, I de-duplicate pipelines post-specialization using the final `VertexBufferLayout` as the key.  For example, consider a pipeline that needs the layout `(position, normal)` and is specialized using two meshes: `(position, normal, uv)` and `(position, normal, other_vec2)`. If both of these meshes result in `(position, normal)` specializations, we can use the same pipeline! Now we do. Cool!

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

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

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

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

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

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

This is still a draft because I still need to:

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

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

Alternative to #3120
Fixes #3030


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-02-23 23:21:13 +00:00
danieleades
d8974e7c3d small and mostly pointless refactoring (#2934)
What is says on the tin.

This has got more to do with making `clippy` slightly more *quiet* than it does with changing anything that might greatly impact readability or performance.

that said, deriving `Default` for a couple of structs is a nice easy win
2022-02-13 22:33:55 +00:00
Robert Swain
0ccb9dd07e bevy_render: Fix Quad flip (#3741)
# Objective

The documentation was unclear but it seemed like it was intended to _only_ flip the texture coordinates of the quad. However, it was also swapping the vertex positions, which resulted in inverted winding order so the front became a back face, and the normal was pointing into the face instead of out of it.

## Solution

- This change makes the only difference the UVs being horizontally flipped.
2022-02-12 00:46:04 +00:00
Michael Dorst
e56685370b Fix doc_markdown lints in bevy_render (#3479)
#3457 adds the `doc_markdown` clippy lint, which checks doc comments to make sure code identifiers are escaped with backticks. This causes a lot of lint errors, so this is one of a number of PR's that will fix those lint errors one crate at a time.

This PR fixes lints in the `bevy_render` crate.
2022-01-09 11:09:46 +00:00
Niklas Eicker
fbab01a40d Add missing closing ticks for inline examples and some cleanup (#3573)
# Objective

- clean up documentation and inline examples

## Solution

- add missing closing "```"
- remove stray "```"
- remove whitespace in inline examples
- unify inline examples (remove some `rust` labels)
2022-01-07 09:25:12 +00:00
Rob Parrett
24b21ea35e Fix torus normals (#3549)
# Objective

Fixes #3547 

## Solution

Normal calc adapted from https://web.cs.ucdavis.edu/~amenta/s12/findnorm.pdf

## Before
<img width="1392" alt="before" src="https://user-images.githubusercontent.com/200550/148125212-fb1c083e-3c57-4330-a656-df34513c36ab.png">

## After
<img width="1392" alt="after" src="https://user-images.githubusercontent.com/200550/148125223-174dc956-37df-4ac2-8983-b18e1e2a9a7d.png">

I'm assuming that the greyness and the self-shadowing artifacts are... normal for the new renderer.
2022-01-04 21:30:46 +00:00
Nicola Papale
035ec7b763 Implement non-indexed mesh rendering (#3415)
# Objective

Instead of panicking when the `indices` field of a mesh is `None`, actually manage it.

This is just a question of keeping track of the vertex buffer size.

## Notes

* Relying on this change to improve performance on [bevy_debug_lines using the new renderer](https://github.com/Toqozz/bevy_debug_lines/pull/10)
* I'm still new to rendering, my only expertise with wgpu is the learn-wgpu tutorial, likely I'm overlooking something.
2021-12-23 19:19:13 +00:00
François
6c479649bf enable Webgl2 optimisation in pbr under feature (#3291)
# Objective

- 3d examples fail to run in webgl2 because of unsupported texture formats or texture too large

## Solution

- switch to supported formats if a feature is enabled. I choose a feature instead of a build target to not conflict with a potential webgpu support

Very inspired by 6813b2edc5, and need #3290 to work.

I named the feature `webgl2`, but it's only needed if one want to use PBR in webgl2. Examples using only 2D already work.

Co-authored-by: François <8672791+mockersf@users.noreply.github.com>
2021-12-22 20:59:48 +00:00
Dusty DeWeese
73f524f61c Support topologies other than TriangleList (#3349)
# Objective

Fixes https://github.com/bevyengine/bevy/issues/3346

## Solution

I've encoded the topology in the `MeshKey` similar to how MSAA samples are handled.
2021-12-18 20:55:40 +00:00
François
6a0008f3d3 Fix doc warnings (#3339)
# Objective

- There are a few warnings when building Bevy docs for dead links
- CI seems to not catch those warnings when it should

## Solution

- Enable doc CI on all Bevy workspace
- Fix warnings
- Also noticed plugin GilrsPlugin was not added anymore when feature was enabled


First commit to check that CI would actually fail with it: https://github.com/bevyengine/bevy/runs/4532652688?check_suite_focus=true

Co-authored-by: François <8672791+mockersf@users.noreply.github.com>
2021-12-18 00:09:23 +00:00
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
Rostyslav Toch
a4e85536c1 Fix clippy errors related to IntoIter::new (#3269)
# Objective

Fixes recent pipeline errors:
```
error: use of deprecated associated function `std::array::IntoIter::<T, N>::new`: use `IntoIterator::into_iter` instead
   --> crates/bevy_render/src/mesh/mesh.rs:467:54
    |
467 |             .flat_map(|normal| std::array::IntoIter::new([normal, normal, normal]))
    |                                                      ^^^
    |
    = note: `-D deprecated` implied by `-D warnings`

   Compiling bevy_render2 v0.5.0 (/home/runner/work/bevy/bevy/pipelined/bevy_render2)
error: use of deprecated associated function `std::array::IntoIter::<T, N>::new`: use `IntoIterator::into_iter` instead
   --> pipelined/bevy_render2/src/mesh/mesh/mod.rs:287:54
    |
287 |             .flat_map(|normal| std::array::IntoIter::new([normal, normal, normal]))
    |                                                      ^^^
    |
    = note: `-D deprecated` implied by `-D warnings`

error: could not compile `bevy_render` due to previous error
```

## Solution

- Replaced `IntoIter::new` with `IntoIterator::into_iter`

## Suggestions

For me it looks like two equivalent `Mesh` structs with the same methods. Should we refactor it? Or, they will be different in the near future?


Co-authored-by: CrazyRoka <rokarostuk@gmail.com>
2021-12-06 22:26:35 +00:00
Yoh Deadfall
ffde86efa0 Update to edition 2021 on master (#3028)
Objective
During work on #3009 I've found that not all jobs use actions-rs, and therefore, an previous version of Rust is used for them. So while compilation and other stuff can pass, checking markup and Android build may fail with compilation errors.

Solution
This PR adds `action-rs` for any job running cargo, and updates the edition to 2021.
2021-10-27 00:12:14 +00:00
Carter Anderson
9d453530fa System Param Lifetime Split (#2605)
# Objective

Enable using exact World lifetimes during read-only access . This is motivated by the new renderer's need to allow read-only world-only queries to outlive the query itself (but still be constrained by the world lifetime).

For example:
115b170d1f/pipelined/bevy_pbr2/src/render/mod.rs (L774)

## Solution

Split out SystemParam state and world lifetimes and pipe those lifetimes up to read-only Query ops (and add into_inner for Res). According to every safety test I've run so far (except one), this is safe (see the temporary safety test commit). Note that changing the mutable variants to the new lifetimes would allow aliased mutable pointers (try doing that to see how it affects the temporary safety tests).

The new state lifetime on SystemParam does make `#[derive(SystemParam)]` more cumbersome (the current impl requires PhantomData if you don't use both lifetimes). We can make this better by detecting whether or not a lifetime is used in the derive and adjusting accordingly, but that should probably be done in its own pr.  

## Why is this a draft?

The new lifetimes break QuerySet safety in one very specific case (see the query_set system in system_safety_test). We need to solve this before we can use the lifetimes given.

This is due to the fact that QuerySet is just a wrapper over Query, which now relies on world lifetimes instead of `&self` lifetimes to prevent aliasing (but in systems, each Query has its own implied lifetime, not a centralized world lifetime).  I believe the fix is to rewrite QuerySet to have its own World lifetime (and own the internal reference). This will complicate the impl a bit, but I think it is doable. I'm curious if anyone else has better ideas.

Personally, I think these new lifetimes need to happen. We've gotta have a way to directly tie read-only World queries to the World lifetime. The new renderer is the first place this has come up, but I doubt it will be the last. Worst case scenario we can come up with a second `WorldLifetimeQuery<Q, F = ()>` parameter to enable these read-only scenarios, but I'd rather not add another type to the type zoo.
2021-08-15 20:51:53 +00:00
Boxy
5ffff03b33 Fix some nightly clippy lints (#2522)
on nightly these two clippy lints fail:
- [needless_borrow](https://rust-lang.github.io/rust-clippy/master/#needless_borrow)
- [unused_unit](https://rust-lang.github.io/rust-clippy/master/#unused_unit)
2021-07-29 20:52:15 +00:00
Paweł Grabarz
189df30a83 use bytemuck crate instead of Byteable trait (#2183)
This gets rid of multiple unsafe blocks that we had to maintain ourselves, and instead depends on library that's commonly used and supported by the ecosystem. We also get support for glam types for free.

There is still some things to clear up with the `Bytes` trait, but that is a bit more substantial change and can be done separately. Also there are already separate efforts to use `crevice` crate, so I've just added that as a TODO.
2021-05-17 22:29:10 +00:00
Jonas Matser
d1f40148fd Allows a number of clippy lints and fixes 2 (#1999)
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-05-14 20:37:32 +00:00
Felipe Jorge
41d9122740 Mesh vertex attributes for skinning and animation (#1831)
Required by #1429,

- Adds the `Ushort4` vertex attribute for joint indices
- `Mesh::ATTRIBUTE_JOINT_WEIGHT` and `Mesh::ATTRIBUTE_JOINT_INDEX` to import vertex attributes related to skinning from GLTF
- impl `Default` for `Mesh` a empty triangle mesh is created (needed by reflect)
- impl `Reflect` for `Mesh` all attributes are ignored (needed by the animation system)
2021-05-06 03:31:20 +00:00
François
afaf4ad3da update for wgpu 0.8 (#1959)
Changes to get Bevy to compile with wgpu master.

With this, on a Mac:
* 2d examples look fine
* ~~3d examples crash with an error specific to metal about a compilation error~~
* 3d examples work fine after enabling feature `wgpu/cross`


Feature `wgpu/cross` seems to be needed only on some platforms, not sure how to know which. It was introduced in https://github.com/gfx-rs/wgpu-rs/pull/826
2021-05-02 20:45:25 +00:00
TehPers
cf40f4ab08 Fix mesh with no vertex attributes causing panic (#2036)
If a mesh without any vertex attributes is rendered (for example, one that only has indices), bevy will crash since the mesh still creates a vertex buffer even though it's empty. Later code assumes that there is vertex data, causing an index-out-of-bounds panic. This PR fixes the issue by adding a check that there is any vertex data before creating a vertex buffer.

I ran into this issue while rendering a tilemap without any vertex attributes (only indices).

Stack trace:
```
thread 'main' panicked at 'index out of bounds: the len is 0 but the index is 0', C:\Dev\Games\bevy\crates\bevy_render\src\render_graph\nodes\pass_node.rs:346:9
stack backtrace:
   0: std::panicking::begin_panic_handler
             at /rustc/bb491ed23937aef876622e4beb68ae95938b3bf9\/library\std\src\panicking.rs:493
   1: core::panicking::panic_fmt
             at /rustc/bb491ed23937aef876622e4beb68ae95938b3bf9\/library\core\src\panicking.rs:92
   2: core::panicking::panic_bounds_check
             at /rustc/bb491ed23937aef876622e4beb68ae95938b3bf9\/library\core\src\panicking.rs:69
   3: core::slice::index::{{impl}}::index<core::option::Option<tuple<bevy_render::renderer::render_resource::buffer::BufferId, u64>>>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\slice\index.rs:184
   4: core::slice::index::{{impl}}::index<core::option::Option<tuple<bevy_render::renderer::render_resource::buffer::BufferId, u64>>,usize>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\slice\index.rs:15
   5: alloc::vec::{{impl}}::index<core::option::Option<tuple<bevy_render::renderer::render_resource::buffer::BufferId, u64>>,usize,alloc::alloc::Global>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\alloc\src\vec\mod.rs:2386
   6: bevy_render::render_graph::nodes::pass_node::DrawState::is_vertex_buffer_set
             at C:\Dev\Games\bevy\crates\bevy_render\src\render_graph\nodes\pass_node.rs:346
   7: bevy_render::render_graph::nodes::pass_node::{{impl}}::update::{{closure}}<bevy_render::render_graph::base::MainPass*>
             at C:\Dev\Games\bevy\crates\bevy_render\src\render_graph\nodes\pass_node.rs:285
   8: bevy_wgpu::renderer::wgpu_render_context::{{impl}}::begin_pass
             at C:\Dev\Games\bevy\crates\bevy_wgpu\src\renderer\wgpu_render_context.rs:196
   9: bevy_render::render_graph::nodes::pass_node::{{impl}}::update<bevy_render::render_graph::base::MainPass*>
             at C:\Dev\Games\bevy\crates\bevy_render\src\render_graph\nodes\pass_node.rs:244
  10: bevy_wgpu::renderer::wgpu_render_graph_executor::WgpuRenderGraphExecutor::execute
             at C:\Dev\Games\bevy\crates\bevy_wgpu\src\renderer\wgpu_render_graph_executor.rs:75
  11: bevy_wgpu::wgpu_renderer::{{impl}}::run_graph::{{closure}}
             at C:\Dev\Games\bevy\crates\bevy_wgpu\src\wgpu_renderer.rs:115
  12: bevy_ecs::world::World::resource_scope<bevy_render::render_graph::graph::RenderGraph,tuple<>,closure-0>
             at C:\Dev\Games\bevy\crates\bevy_ecs\src\world\mod.rs:715
  13: bevy_wgpu::wgpu_renderer::WgpuRenderer::run_graph
             at C:\Dev\Games\bevy\crates\bevy_wgpu\src\wgpu_renderer.rs:104
  14: bevy_wgpu::wgpu_renderer::WgpuRenderer::update
             at C:\Dev\Games\bevy\crates\bevy_wgpu\src\wgpu_renderer.rs:121
  15: bevy_wgpu::get_wgpu_render_system::{{closure}}
             at C:\Dev\Games\bevy\crates\bevy_wgpu\src\lib.rs:112
  16: alloc::boxed::{{impl}}::call_mut<tuple<mut bevy_ecs::world::World*>,FnMut<tuple<mut bevy_ecs::world::World*>>,alloc::alloc::Global>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\alloc\src\boxed.rs:1553
  17: bevy_ecs::system::exclusive_system::{{impl}}::run
             at C:\Dev\Games\bevy\crates\bevy_ecs\src\system\exclusive_system.rs:41
  18: bevy_ecs::schedule::stage::{{impl}}::run
             at C:\Dev\Games\bevy\crates\bevy_ecs\src\schedule\stage.rs:812
  19: bevy_ecs::schedule::Schedule::run_once
             at C:\Dev\Games\bevy\crates\bevy_ecs\src\schedule\mod.rs:201
  20: bevy_ecs::schedule::{{impl}}::run
             at C:\Dev\Games\bevy\crates\bevy_ecs\src\schedule\mod.rs:219
  21: bevy_app::app::App::update
             at C:\Dev\Games\bevy\crates\bevy_app\src\app.rs:58
  22: bevy_winit::winit_runner_with::{{closure}}
             at C:\Dev\Games\bevy\crates\bevy_winit\src\lib.rs:485
  23: winit::platform_impl::platform::event_loop::{{impl}}::run_return::{{closure}}<tuple<>,closure-1>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop.rs:203
  24: alloc::boxed::{{impl}}::call_mut<tuple<winit::event::Event<tuple<>>, mut winit::event_loop::ControlFlow*>,FnMut<tuple<winit::event::Event<tuple<>>, mut winit::event_loop::ControlFlow*>>,alloc::alloc::Global>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\alloc\src\boxed.rs:1553
  25: winit::platform_impl::platform::event_loop:🏃:{{impl}}::call_event_handler::{{closure}}<tuple<>>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop\runner.rs:245
  26: std::panic::{{impl}}::call_once<tuple<>,closure-0>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panic.rs:344
  27: std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure-0>,tuple<>>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:379
  28: hashbrown::set::HashSet<mut winapi::shared::windef::HWND__*, std::collections:#️⃣:map::RandomState, alloc::alloc::Global>::iter<mut winapi::shared::windef::HWND__*,std::collections:#️⃣:map::RandomState,alloc::alloc::Global>
  29: std::panicking::try<tuple<>,std::panic::AssertUnwindSafe<closure-0>>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:343
  30: std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure-0>,tuple<>>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panic.rs:431
  31: winit::platform_impl::platform::event_loop:🏃:EventLoopRunner<tuple<>>::catch_unwind<tuple<>,tuple<>,closure-0>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop\runner.rs:152
  32: winit::platform_impl::platform::event_loop:🏃:EventLoopRunner<tuple<>>::call_event_handler<tuple<>>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop\runner.rs:239
  33: winit::platform_impl::platform::event_loop:🏃:EventLoopRunner<tuple<>>::move_state_to<tuple<>>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop\runner.rs:341
  34: winit::platform_impl::platform::event_loop:🏃:EventLoopRunner<tuple<>>::main_events_cleared<tuple<>>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop\runner.rs:227
  35: winit::platform_impl::platform::event_loop::flush_paint_messages<tuple<>>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop.rs:676
  36: winit::platform_impl::platform::event_loop::thread_event_target_callback::{{closure}}<tuple<>>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop.rs:1967
  37: std::panic::{{impl}}::call_once<isize,closure-0>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panic.rs:344
  38: std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure-0>,isize>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:379
  39: hashbrown::set::HashSet<mut winapi::shared::windef::HWND__*, std::collections:#️⃣:map::RandomState, alloc::alloc::Global>::iter<mut winapi::shared::windef::HWND__*,std::collections:#️⃣:map::RandomState,alloc::alloc::Global>
  40: std::panicking::try<isize,std::panic::AssertUnwindSafe<closure-0>>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:343
  41: std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure-0>,isize>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panic.rs:431
  42: winit::platform_impl::platform::event_loop:🏃:EventLoopRunner<tuple<>>::catch_unwind<tuple<>,isize,closure-0>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop\runner.rs:152
  43: winit::platform_impl::platform::event_loop::thread_event_target_callback<tuple<>>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop.rs:2151
  44: DefSubclassProc
  45: DefSubclassProc
  46: CallWindowProcW
  47: DispatchMessageW
  48: SendMessageTimeoutW
  49: KiUserCallbackDispatcher
  50: NtUserDispatchMessage
  51: DispatchMessageW
  52: winit::platform_impl::platform::event_loop::EventLoop<tuple<>>::run_return<tuple<>,closure-1>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop.rs:218
  53: winit::platform_impl::platform::event_loop::EventLoop<tuple<>>::run<tuple<>,closure-1>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\platform_impl\windows\event_loop.rs:188
  54: winit::event_loop::EventLoop<tuple<>>::run<tuple<>,closure-1>
             at C:\Users\tehpe\.cargo\registry\src\github.com-1ecc6299db9ec823\winit-0.24.0\src\event_loop.rs:154
  55: bevy_winit::run<closure-1>
             at C:\Dev\Games\bevy\crates\bevy_winit\src\lib.rs:171
  56: bevy_winit::winit_runner_with
             at C:\Dev\Games\bevy\crates\bevy_winit\src\lib.rs:493
  57: bevy_winit::winit_runner
             at C:\Dev\Games\bevy\crates\bevy_winit\src\lib.rs:211
  58: core::ops::function::Fn::call<fn(bevy_app::app::App),tuple<bevy_app::app::App>>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\ops\function.rs:70
  59: alloc::boxed::{{impl}}::call<tuple<bevy_app::app::App>,Fn<tuple<bevy_app::app::App>>,alloc::alloc::Global>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\alloc\src\boxed.rs:1560
  60: bevy_app::app::App::run
             at C:\Dev\Games\bevy\crates\bevy_app\src\app.rs:68
  61: bevy_app::app_builder::AppBuilder::run
             at C:\Dev\Games\bevy\crates\bevy_app\src\app_builder.rs:54
  62: game_main::main
             at .\crates\game_main\src\main.rs:23
  63: core::ops::function::FnOnce::call_once<fn(),tuple<>>
             at C:\Users\tehpe\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\ops\function.rs:227
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
Apr 27 21:51:01.026 ERROR gpu_descriptor::allocator: `DescriptorAllocator` is dropped while some descriptor sets were not deallocated
error: process didn't exit successfully: `target/cargo\debug\game_main.exe` (exit code: 0xc000041d)
```
2021-04-28 19:04:01 +00:00
Carter Anderson
1248a639ee EnumVariantMeta derive (#1972)
There are cases where we want an enum variant name. Right now the only way to do that with rust's std is to derive Debug, but this will also print out the variant's fields. This creates the unfortunate situation where we need to manually write out each variant's string name (ex: in #1963), which is both boilerplate-ey and error-prone. Crates such as `strum` exist for this reason, but it includes a lot of code and complexity that we don't need.

This adds a dead-simple `EnumVariantMeta` derive that exposes `enum_variant_index` and `enum_variant_name` functions. This allows us to make cases like #1963 much cleaner (see the second commit). We might also be able to reuse this logic for `bevy_reflect` enum derives.
2021-04-21 23:46:54 +00:00
Alice Cecile
e4e32598a9 Cargo fmt with unstable features (#1903)
Fresh version of #1670 off the latest main.

Mostly fixing documentation wrapping.
2021-04-21 23:19:34 +00:00
simens_green
c74994ba69 Added TryFrom for VertexAttributeValues (#1963)
This implementations allows you
convert std::vec::Vec<T> to VertexAttributeValues::T and back.

# Examples

```rust
use std::convert::TryInto;
use bevy_render::mesh::VertexAttributeValues;

// creating vector of values
let before = vec![[0_u32; 4]; 10];
let values = VertexAttributeValues::from(before.clone());
let after: Vec<[u32; 4]> = values.try_into().unwrap();

assert_eq!(before, after);
```

Co-authored-by: aloucks <aloucks@cofront.net>
Co-authored-by: simens_green <34134129+simensgreen@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-04-20 20:41:32 +00:00
Jakob Hellermann
cf221f9659 calculate flat normals for mesh if missing (#1808)
If the gltf loader encounters a mesh without normal attributes, it will duplicate the vertex attributes and compute flat normals, as defined by https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#meshes:

> **Implementation Note**: When normals are not specified, client implementations should calculate flat normals.

![image](https://user-images.githubusercontent.com/22177966/113483243-bb204880-94a2-11eb-8fa1-c4828a4882c5.png)

Helps with #1802 

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-04-15 21:06:49 +00:00
Denis Laprise
d8392e7a3e Add a UV sphere implementation (#1887)
Added a UV sphere implementation
2021-04-14 23:39:58 +00:00
aloucks
294feeedc0 Add additional vertex formats (#1878)
- `Short2`
- `Short2Norm`
- `Ushort2`
- `Ushort2Norm`
- `Short4`
- `Short4Norm`
- `Ushort4`
- `Ushort4Norm`
- `Char2`
- `Char2Norm`
- `Uchar2`
- `Uchar2Norm`
- `Char4`
- `Char4Norm`
- `Uchar4`
2021-04-14 23:21:53 +00:00
Patrik Buhring
df3f40afd4 Fix IcoSphere UV coordinates (#1871)
Changes made:
- Swap Y/Z when calculating UV coordinates
- Correct mapping in the UV coordinates
- Fix typo in Azimuth
2021-04-14 22:20:24 +00:00
Yoh Deadfall
04a37f722a Moved events to ECS (#1823)
Fixes #1809. It makes it also possible to use `derive` for `SystemParam` inside ECS and avoid manual implementation. An alternative solution to macro changes is to use `use crate as bevy_ecs;` in `event.rs`.
2021-04-13 20:36:37 +00:00
Jonas Matser
7342d463b8 Use a sorted Map for vertex buffer attributes (#1796)
The `VertexBufferLayout` returned by `crates\bevy_render\src\mesh\mesh.rs:308` was unstable, because `HashMap.iter()` has a random order. This caused the pipeline_compiler to wrongly consider a specialization to be different (`crates\bevy_render\src\pipeline\pipeline_compiler.rs:123`), causing each mesh changed event to potentially result in a different `PipelineSpecialization`. This in turn caused `Draw` to emit a `set_pipeline` much more often than needed.

This fix shaves off a `BindPipeline` and two `BindDescriptorSets` (for the Camera and for global renderresources) for every mesh after the first that can now use the same specialization, where it didn't before (which was random).

`StableHashMap` was not a good replacement, because it isn't `Clone`, so instead I replaced it with a `BTreeMap` which is OK in this instance, because there shouldn't be many insertions on `Mesh.attributes` after the mesh is created.
2021-04-13 03:31:29 +00:00
Jonas Matser
9a78addff0 Add PBR textures (#1632)
This PR adds normal maps on top of PBR #1554. Once that PR lands, the changes should look simpler.

Edit: Turned out to be so little extra work, I added metallic/roughness texture too. And occlusion and emissive.

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-03-26 21:00:34 +00:00
Alice Cecile
6121e5f933 Reliable change detection (#1471)
# Problem Definition

The current change tracking (via flags for both components and resources) fails to detect changes made by systems that are scheduled to run earlier in the frame than they are.

This issue is discussed at length in [#68](https://github.com/bevyengine/bevy/issues/68) and [#54](https://github.com/bevyengine/bevy/issues/54).

This is very much a draft PR, and contributions are welcome and needed.

# Criteria
1. Each change is detected at least once, no matter the ordering.
2. Each change is detected at most once, no matter the ordering.
3. Changes should be detected the same frame that they are made.
4. Competitive ergonomics. Ideally does not require opting-in.
5. Low CPU overhead of computation.
6. Memory efficient. This must not increase over time, except where the number of entities / resources does.
7. Changes should not be lost for systems that don't run.
8. A frame needs to act as a pure function. Given the same set of entities / components it needs to produce the same end state without side-effects.

**Exact** change-tracking proposals satisfy criteria 1 and 2.
**Conservative** change-tracking proposals satisfy criteria 1 but not 2.
**Flaky** change tracking proposals satisfy criteria 2 but not 1.

# Code Base Navigation

There are three types of flags: 
- `Added`: A piece of data was added to an entity / `Resources`.
- `Mutated`: A piece of data was able to be modified, because its `DerefMut` was accessed
- `Changed`: The bitwise OR of `Added` and `Changed`

The special behavior of `ChangedRes`, with respect to the scheduler is being removed in [#1313](https://github.com/bevyengine/bevy/pull/1313) and does not need to be reproduced.

`ChangedRes` and friends can be found in "bevy_ecs/core/resources/resource_query.rs".

The `Flags` trait for Components can be found in "bevy_ecs/core/query.rs".

`ComponentFlags` are stored in "bevy_ecs/core/archetypes.rs", defined on line 446.

# Proposals

**Proposal 5 was selected for implementation.**

## Proposal 0: No Change Detection

The baseline, where computations are performed on everything regardless of whether it changed.

**Type:** Conservative

**Pros:**
- already implemented
- will never miss events
- no overhead

**Cons:**
- tons of repeated work
- doesn't allow users to avoid repeating work (or monitoring for other changes)

## Proposal 1: Earlier-This-Tick Change Detection

The current approach as of Bevy 0.4. Flags are set, and then flushed at the end of each frame.

**Type:** Flaky

**Pros:**
- already implemented
- simple to understand
- low memory overhead (2 bits per component)
- low time overhead (clear every flag once per frame)

**Cons:**
- misses systems based on ordering
- systems that don't run every frame miss changes
- duplicates detection when looping
- can lead to unresolvable circular dependencies

## Proposal 2: Two-Tick Change Detection

Flags persist for two frames, using a double-buffer system identical to that used in events.

A change is observed if it is found in either the current frame's list of changes or the previous frame's.

**Type:** Conservative

**Pros:**
- easy to understand
- easy to implement
- low memory overhead (4 bits per component)
- low time overhead (bit mask and shift every flag once per frame)

**Cons:**
- can result in a great deal of duplicated work
- systems that don't run every frame miss changes
- duplicates detection when looping

## Proposal 3: Last-Tick Change Detection

Flags persist for two frames, using a double-buffer system identical to that used in events.

A change is observed if it is found in the previous frame's list of changes.

**Type:** Exact

**Pros:**
- exact
- easy to understand
- easy to implement
- low memory overhead (4 bits per component)
- low time overhead (bit mask and shift every flag once per frame)

**Cons:**
- change detection is always delayed, possibly causing painful chained delays
- systems that don't run every frame miss changes
- duplicates detection when looping

## Proposal 4: Flag-Doubling Change Detection

Combine Proposal 2 and Proposal 3. Differentiate between `JustChanged` (current behavior) and `Changed` (Proposal 3).

Pack this data into the flags according to [this implementation proposal](https://github.com/bevyengine/bevy/issues/68#issuecomment-769174804).

**Type:** Flaky + Exact

**Pros:**
- allows users to acc
- easy to implement
- low memory overhead (4 bits per component)
- low time overhead (bit mask and shift every flag once per frame)

**Cons:**
- users must specify the type of change detection required
- still quite fragile to system ordering effects when using the flaky `JustChanged` form
- cannot get immediate + exact results
- systems that don't run every frame miss changes
- duplicates detection when looping

## [SELECTED] Proposal 5: Generation-Counter Change Detection

A global counter is increased after each system is run. Each component saves the time of last mutation, and each system saves the time of last execution. Mutation is detected when the component's counter is greater than the system's counter. Discussed [here](https://github.com/bevyengine/bevy/issues/68#issuecomment-769174804). How to handle addition detection is unsolved; the current proposal is to use the highest bit of the counter as in proposal 1.

**Type:** Exact (for mutations), flaky (for additions)

**Pros:**
- low time overhead (set component counter on access, set system counter after execution)
- robust to systems that don't run every frame
- robust to systems that loop

**Cons:**
- moderately complex implementation
- must be modified as systems are inserted dynamically
- medium memory overhead (4 bytes per component + system)
- unsolved addition detection

## Proposal 6: System-Data Change Detection

For each system, track which system's changes it has seen. This approach is only worth fully designing and implementing if Proposal 5 fails in some way.  

**Type:** Exact

**Pros:**
- exact
- conceptually simple

**Cons:**
- requires storing data on each system
- implementation is complex
- must be modified as systems are inserted dynamically

## Proposal 7: Total-Order Change Detection

Discussed [here](https://github.com/bevyengine/bevy/issues/68#issuecomment-754326523). This proposal is somewhat complicated by the new scheduler, but I believe it should still be conceptually feasible. This approach is only worth fully designing and implementing if Proposal 5 fails in some way.  

**Type:** Exact

**Pros:**
- exact
- efficient data storage relative to other exact proposals

**Cons:**
- requires access to the scheduler
- complex implementation and difficulty grokking
- must be modified as systems are inserted dynamically

# Tests

- We will need to verify properties 1, 2, 3, 7 and 8. Priority: 1 > 2 = 3 > 8 > 7
- Ideally we can use identical user-facing syntax for all proposals, allowing us to re-use the same syntax for each.
- When writing tests, we need to carefully specify order using explicit dependencies.
- These tests will need to be duplicated for both components and resources.
- We need to be sure to handle cases where ambiguous system orders exist.

`changing_system` is always the system that makes the changes, and `detecting_system` always detects the changes.

The component / resource changed will be simple boolean wrapper structs.

## Basic Added / Mutated / Changed

2 x 3 design:
- Resources vs. Components
- Added vs. Changed vs. Mutated
- `changing_system` runs before `detecting_system`
- verify at the end of tick 2

## At Least Once

2 x 3 design:
- Resources vs. Components
- Added vs. Changed vs. Mutated
- `changing_system` runs after `detecting_system`
- verify at the end of tick 2

## At Most Once

2 x 3 design:
- Resources vs. Components
- Added vs. Changed vs. Mutated
- `changing_system` runs once before `detecting_system`
- increment a counter based on the number of changes detected
- verify at the end of tick 2

## Fast Detection
2 x 3 design:
- Resources vs. Components
- Added vs. Changed vs. Mutated
- `changing_system` runs before `detecting_system`
- verify at the end of tick 1

## Ambiguous System Ordering Robustness
2 x 3 x 2 design:
- Resources vs. Components
- Added vs. Changed vs. Mutated
- `changing_system` runs [before/after] `detecting_system` in tick 1
- `changing_system` runs [after/before] `detecting_system` in tick 2

## System Pausing
2 x 3 design:
- Resources vs. Components
- Added vs. Changed vs. Mutated
- `changing_system` runs in tick 1, then is disabled by run criteria
- `detecting_system` is disabled by run criteria until it is run once during tick 3
- verify at the end of tick 3

## Addition Causes Mutation

2 design:
- Resources vs. Components
- `adding_system_1` adds a component / resource
- `adding system_2` adds the same component / resource
- verify the `Mutated` flag at the end of the tick
- verify the `Added` flag at the end of the tick

First check tests for: https://github.com/bevyengine/bevy/issues/333
Second check tests for: https://github.com/bevyengine/bevy/issues/1443

## Changes Made By Commands

- `adding_system` runs in Update in tick 1, and sends a command to add a component 
- `detecting_system` runs in Update in tick 1 and 2, after `adding_system`
- We can't detect the changes in tick 1, since they haven't been processed yet
- If we were to track these changes as being emitted by `adding_system`, we can't detect the changes in tick 2 either, since `detecting_system` has already run once after `adding_system` :( 

# Benchmarks

See: [general advice](https://github.com/bevyengine/bevy/blob/master/docs/profiling.md), [Criterion crate](https://github.com/bheisler/criterion.rs)

There are several critical parameters to vary: 
1. entity count (1 to 10^9)
2. fraction of entities that are changed (0% to 100%)
3. cost to perform work on changed entities, i.e. workload (1 ns to 1s)

1 and 2 should be varied between benchmark runs. 3 can be added on computationally.

We want to measure:
- memory cost
- run time

We should collect these measurements across several frames (100?) to reduce bootup effects and accurately measure the mean, variance and drift.

Entity-component change detection is much more important to benchmark than resource change detection, due to the orders of magnitude higher number of pieces of data.

No change detection at all should be included in benchmarks as a second control for cases where missing changes is unacceptable.

## Graphs
1. y: performance, x: log_10(entity count), color: proposal, facet: performance metric. Set cost to perform work to 0. 
2. y: run time, x: cost to perform work, color: proposal, facet: fraction changed. Set number of entities to 10^6
3. y: memory, x: frames, color: proposal

# Conclusions
1. Is the theoretical categorization of the proposals correct according to our tests?
2. How does the performance of the proposals compare without any load?
3. How does the performance of the proposals compare with realistic loads?
4. At what workload does more exact change tracking become worth the (presumably) higher overhead?
5. When does adding change-detection to save on work become worthwhile?
6. Is there enough divergence in performance between the best solutions in each class to ship more than one change-tracking solution?

# Implementation Plan

1. Write a test suite.
2. Verify that tests fail for existing approach.
3. Write a benchmark suite.
4. Get performance numbers for existing approach.
5. Implement, test and benchmark various solutions using a Git branch per proposal.
6. Create a draft PR with all solutions and present results to team.
7. Select a solution and replace existing change detection.

Co-authored-by: Brice DAVIER <bricedavier@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-03-19 17:53:26 +00:00
Jakob Hellermann
f6ff80c5b1
add Debug, Copy, Clone for all shapes (#1653) 2021-03-14 12:45:00 -07:00
François
bbb9849506 Replace default method calls from Glam types with explicit const (#1645)
it's a followup of #1550 

I think calling explicit methods/values instead of default makes the code easier to read: "what is `Quat::default()`" vs "Oh, it's `Quat::IDENTITY`"

`Transform::identity()` and `GlobalTransform::identity()` can also be consts and I replaced the calls to their `default()` impl with `identity()`
2021-03-13 18:23:39 +00:00
Carter Anderson
b17f8a4bce format comments (#1612)
Uses the new unstable comment formatting features added to rustfmt.toml.
2021-03-11 00:27:30 +00:00