# Objective
On iOS:
- Allow `std` to do its runtime initialization.
- Avoid requiring the user to specify linked libraries and framework in
Xcode.
- Reduce the amount of work that `#[bevy_main]` does
- In the future we may also be able to eliminate the need for it on
Android, cc @daxpedda.
## Solution
We previously:
- Exposed an `extern "C" fn main_rs` entry point.
- Ran Cargo in a separate Xcode target as an external build system.
- Imported that as a dependency of `bevy_mobile_example.app`.
- Compiled a trampoline C file with Xcode that called `main_rs`.
- Linked that via. Xcode.
All of this is unnecessary; `rustc` is well capable of creating iOS
executables, the trick is just to place it at the correct location for
Xcode to understand it, namely `$TARGET_BUILD_DIR/$EXECUTABLE_PATH`
(places it in `bevy_mobile_example.app/bevy_mobile_example`).
Note: We might want to wait with the changes to `#[bevy_main]` until the
problem is resolved on Android too, to make the migration easier.
## Testing
Open the Xcode project, and build for an iOS target.
---
## Migration Guide
**If you have been building your application for iOS:**
Previously, the `#[bevy_main]` attribute created a `main_rs` entry point
that most Xcode templates were using to run your Rust code from C. This
was found to be unnecessary, as you can simply let Rust build your
application as a binary, and run that directly.
You have two options for dealing with this:
If you've added further C code and Xcode customizations, or it makes
sense for your use-case to continue link with Xcode, you can revert to
the old behaviour by adding `#[no_mangle] extern "C" main_rs() { main()
}` to your `main.rs`. Note that the old approach of linking a static
library prevents the Rust standard library from doing runtime
initialization, so certain functionality provided by `std` might be
unavailable (stack overflow handlers, stdout/stderr flushing and other
such functionality provided by the initialization routines).
The other, preferred option is to remove your "compile" and "link" build
phases, and instead replace it with a "run script" phase that invokes
`cargo build --bin ...`, and moves the built binary to the Xcode path
`$TARGET_BUILD_DIR/$EXECUTABLE_PATH`. An example of how to do this can
be viewed at [INSERT LINK TO UPDATED EXAMPLE PROJECT].
To make the debugging experience in Xcode nicer after this, you might
also want to consider either enabling `panic = "abort"` or to set a
breakpoint on the `rust_panic` symbol.
---------
Co-authored-by: François Mockers <mockersf@gmail.com>
Co-authored-by: François Mockers <francois.mockers@vleue.com>
# Objective
- Fixes#17960
## Solution
- Followed the [edition upgrade
guide](https://doc.rust-lang.org/edition-guide/editions/transitioning-an-existing-project-to-a-new-edition.html)
## Testing
- CI
---
## Summary of Changes
### Documentation Indentation
When using lists in documentation, proper indentation is now linted for.
This means subsequent lines within the same list item must start at the
same indentation level as the item.
```rust
/* Valid */
/// - Item 1
/// Run-on sentence.
/// - Item 2
struct Foo;
/* Invalid */
/// - Item 1
/// Run-on sentence.
/// - Item 2
struct Foo;
```
### Implicit `!` to `()` Conversion
`!` (the never return type, returned by `panic!`, etc.) no longer
implicitly converts to `()`. This is particularly painful for systems
with `todo!` or `panic!` statements, as they will no longer be functions
returning `()` (or `Result<()>`), making them invalid systems for
functions like `add_systems`. The ideal fix would be to accept functions
returning `!` (or rather, _not_ returning), but this is blocked on the
[stabilisation of the `!` type
itself](https://doc.rust-lang.org/std/primitive.never.html), which is
not done.
The "simple" fix would be to add an explicit `-> ()` to system
signatures (e.g., `|| { todo!() }` becomes `|| -> () { todo!() }`).
However, this is _also_ banned, as there is an existing lint which (IMO,
incorrectly) marks this as an unnecessary annotation.
So, the "fix" (read: workaround) is to put these kinds of `|| -> ! { ...
}` closuers into variables and give the variable an explicit type (e.g.,
`fn()`).
```rust
// Valid
let system: fn() = || todo!("Not implemented yet!");
app.add_systems(..., system);
// Invalid
app.add_systems(..., || todo!("Not implemented yet!"));
```
### Temporary Variable Lifetimes
The order in which temporary variables are dropped has changed. The
simple fix here is _usually_ to just assign temporaries to a named
variable before use.
### `gen` is a keyword
We can no longer use the name `gen` as it is reserved for a future
generator syntax. This involved replacing uses of the name `gen` with
`r#gen` (the raw-identifier syntax).
### Formatting has changed
Use statements have had the order of imports changed, causing a
substantial +/-3,000 diff when applied. For now, I have opted-out of
this change by amending `rustfmt.toml`
```toml
style_edition = "2021"
```
This preserves the original formatting for now, reducing the size of
this PR. It would be a simple followup to update this to 2024 and run
`cargo fmt`.
### New `use<>` Opt-Out Syntax
Lifetimes are now implicitly included in RPIT types. There was a handful
of instances where it needed to be added to satisfy the borrow checker,
but there may be more cases where it _should_ be added to avoid
breakages in user code.
### `MyUnitStruct { .. }` is an invalid pattern
Previously, you could match against unit structs (and unit enum
variants) with a `{ .. }` destructuring. This is no longer valid.
### Pretty much every use of `ref` and `mut` are gone
Pattern binding has changed to the point where these terms are largely
unused now. They still serve a purpose, but it is far more niche now.
### `iter::repeat(...).take(...)` is bad
New lint recommends using the more explicit `iter::repeat_n(..., ...)`
instead.
## Migration Guide
The lifetimes of functions using return-position impl-trait (RPIT) are
likely _more_ conservative than they had been previously. If you
encounter lifetime issues with such a function, please create an issue
to investigate the addition of `+ use<...>`.
## Notes
- Check the individual commits for a clearer breakdown for what
_actually_ changed.
---------
Co-authored-by: François Mockers <francois.mockers@vleue.com>
## Objective
Get rid of a redundant Cargo feature flag.
## Solution
Use the built-in `target_abi = "sim"` instead of a custom Cargo feature
flag, which is set for the iOS (and visionOS and tvOS) simulator. This
has been stable since Rust 1.78.
In the future, some of this may become redundant if Wgpu implements
proper supper for the iOS Simulator:
https://github.com/gfx-rs/wgpu/issues/7057
CC @mockersf who implemented [the original
fix](https://github.com/bevyengine/bevy/pull/10178).
## Testing
- Open mobile example in Xcode.
- Launch the simulator.
- See that no errors are emitted.
- Remove the code cfg-guarded behind `target_abi = "sim"`.
- See that an error now happens.
(I haven't actually performed these steps on the latest `main`, because
I'm hitting an unrelated error (EDIT: It was
https://github.com/bevyengine/bevy/pull/17637). But tested it on
0.15.0).
---
## Migration Guide
> If you're using a project that builds upon the mobile example, remove
the `ios_simulator` feature from your `Cargo.toml` (Bevy now handles
this internally).
# Objective
Add two features to switch bevy to use `NativeActivity` or
`GameActivity` on Android, use `GameActivity` by default.
Also close #12058 and probably #12026 .
## Solution
Add two features to the corresponding crates so you can toggle it, like
what `winit` and `android-activity` crate did.
---
## Changelog
Removed default `NativeActivity` feature implementation for Android,
added two new features to enable `NativeActivity` and `GameActivity`,
and use `GameActivity` by default.
## Migration Guide
Because `cargo-apk` is not compatible with `GameActivity`,
building/running using `cargo apk build/run -p bevy_mobile_example` is
no longer possible.
Users should follow the new workflow described in document.
---------
Co-authored-by: François Mockers <francois.mockers@vleue.com>
Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
Co-authored-by: Rich Churcher <rich.churcher@gmail.com>
# Objective
- Fix issue #2611
## Solution
- Add `--generate-link-to-definition` to all the `rustdoc-args` arrays
in the `Cargo.toml`s (for docs.rs)
- Add `--generate-link-to-definition` to the `RUSTDOCFLAGS` environment
variable in the docs workflow (for dev-docs.bevyengine.org)
- Document all the workspace crates in the docs workflow (needed because
otherwise only the source code of the `bevy` package will be included,
making the argument useless)
- I think this also fixes#3662, since it fixes the bug on
dev-docs.bevyengine.org, while on docs.rs it has been fixed for a while
on their side.
---
## Changelog
- The source code viewer on docs.rs now includes links to the
definitions.
# Objective
- The [`version`] field in `Cargo.toml` is optional for crates not
published on <https://crates.io>.
- We have several `publish = false` tools in this repository that still
have a version field, even when it's not useful.
[`version`]:
https://doc.rust-lang.org/cargo/reference/manifest.html#the-version-field
## Solution
- Remove the [`version`] field for all crates where `publish = false`.
- Update the description on a few crates and remove extra newlines as
well.
# Objective
- Fix adding `#![allow(clippy::type_complexity)]` everywhere. like #9796
## Solution
- Use the new [lints] table that will land in 1.74
(https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#lints)
- inherit lint to the workspace, crates and examples.
```
[lints]
workspace = true
```
## Changelog
- Bump rust version to 1.74
- Enable lints table for the workspace
```toml
[workspace.lints.clippy]
type_complexity = "allow"
```
- Allow type complexity for all crates and examples
```toml
[lints]
workspace = true
```
---------
Co-authored-by: Martín Maita <47983254+mnmaita@users.noreply.github.com>
# Objective
The current mobile example produces an APK of 1.5 Gb.
- Running the example on a real device takes significant time (around
one minute just to copy the file over USB to my phone).
- Default virtual devices in Android studio run out of space after the
first install. This can of course be solved/configured, but it causes
unnecessary friction.
- One impression could be, that Bevy produces bloated APKs. 1.5Gb is
even double the size of debug builds for desktop examples.
## Solution
- Strip the debug symbols of the shared libraries before they are copied
to the APK
APK size after this change: 200Mb
Copy time on my machine: ~8s
## Considered alternative
APKs built in release mode are only 50Mb in size, but require setting up
signing for the profile and compile longer.
# Objective
- Merge the examples on iOS and Android
- Make sure they both work from the same code
## Solution
- don't create window when not in an active state (from #6830)
- exit on suspend on Android (from #6830)
- automatically enable dependency feature of bevy_audio on android so that it works out of the box
- don't inverse y position of touch events
- reuse the same example for both Android and iOS
Fixes#4616Fixes#4103Fixes#3648Fixes#3458Fixes#3249Fixes#86
