bevy/crates/bevy_winit/src/web_resize.rs
ira 992681b59b Make Resource trait opt-in, requiring #[derive(Resource)] V2 (#5577)
*This PR description is an edited copy of #5007, written by @alice-i-cecile.*
# Objective
Follow-up to https://github.com/bevyengine/bevy/pull/2254. The `Resource` trait currently has a blanket implementation for all types that meet its bounds.

While ergonomic, this results in several drawbacks:

* it is possible to make confusing, silent mistakes such as inserting a function pointer (Foo) rather than a value (Foo::Bar) as a resource
* it is challenging to discover if a type is intended to be used as a resource
* we cannot later add customization options (see the [RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/27-derive-component.md) for the equivalent choice for Component).
* dependencies can use the same Rust type as a resource in invisibly conflicting ways
* raw Rust types used as resources cannot preserve privacy appropriately, as anyone able to access that type can read and write to internal values
* we cannot capture a definitive list of possible resources to display to users in an editor
## Notes to reviewers
 * Review this commit-by-commit; there's effectively no back-tracking and there's a lot of churn in some of these commits.
   *ira: My commits are not as well organized :')*
 * I've relaxed the bound on Local to Send + Sync + 'static: I don't think these concerns apply there, so this can keep things simple. Storing e.g. a u32 in a Local is fine, because there's a variable name attached explaining what it does.
 * I think this is a bad place for the Resource trait to live, but I've left it in place to make reviewing easier. IMO that's best tackled with https://github.com/bevyengine/bevy/issues/4981.

## Changelog
`Resource` is no longer automatically implemented for all matching types. Instead, use the new `#[derive(Resource)]` macro.

## Migration Guide
Add `#[derive(Resource)]` to all types you are using as a resource.

If you are using a third party type as a resource, wrap it in a tuple struct to bypass orphan rules. Consider deriving `Deref` and `DerefMut` to improve ergonomics.

`ClearColor` no longer implements `Component`. Using `ClearColor` as a component in 0.8 did nothing.
Use the `ClearColorConfig` in the `Camera3d` and `Camera2d` components instead.


Co-authored-by: Alice <alice.i.cecile@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: devil-ira <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-08-08 21:36:35 +00:00

84 lines
2.5 KiB
Rust

use crate::WinitWindows;
use bevy_app::{App, Plugin};
use bevy_ecs::prelude::*;
use bevy_window::WindowId;
use crossbeam_channel::{Receiver, Sender};
use wasm_bindgen::JsCast;
use winit::dpi::LogicalSize;
pub(crate) struct CanvasParentResizePlugin;
impl Plugin for CanvasParentResizePlugin {
fn build(&self, app: &mut App) {
app.init_resource::<CanvasParentResizeEventChannel>()
.add_system(canvas_parent_resize_event_handler);
}
}
struct ResizeEvent {
size: LogicalSize<f32>,
window_id: WindowId,
}
#[derive(Resource)]
pub(crate) struct CanvasParentResizeEventChannel {
sender: Sender<ResizeEvent>,
receiver: Receiver<ResizeEvent>,
}
fn canvas_parent_resize_event_handler(
winit_windows: NonSend<WinitWindows>,
resize_events: Res<CanvasParentResizeEventChannel>,
) {
for event in resize_events.receiver.try_iter() {
if let Some(window) = winit_windows.get_window(event.window_id) {
window.set_inner_size(event.size);
}
}
}
fn get_size(selector: &str) -> Option<LogicalSize<f32>> {
let win = web_sys::window().unwrap();
let doc = win.document().unwrap();
let element = doc.query_selector(selector).ok()??;
let parent_element = element.parent_element()?;
let rect = parent_element.get_bounding_client_rect();
return Some(winit::dpi::LogicalSize::new(
rect.width() as f32,
rect.height() as f32,
));
}
pub(crate) const WINIT_CANVAS_SELECTOR: &str = "canvas[data-raw-handle]";
impl Default for CanvasParentResizeEventChannel {
fn default() -> Self {
let (sender, receiver) = crossbeam_channel::unbounded();
return Self { sender, receiver };
}
}
impl CanvasParentResizeEventChannel {
pub(crate) fn listen_to_selector(&self, window_id: WindowId, selector: &str) {
let sender = self.sender.clone();
let owned_selector = selector.to_string();
let resize = move || {
if let Some(size) = get_size(&owned_selector) {
sender.send(ResizeEvent { size, window_id }).unwrap();
}
};
// ensure resize happens on startup
resize();
let closure = wasm_bindgen::closure::Closure::wrap(Box::new(move |_: web_sys::Event| {
resize();
}) as Box<dyn FnMut(_)>);
let window = web_sys::window().unwrap();
window
.add_event_listener_with_callback("resize", closure.as_ref().unchecked_ref())
.unwrap();
closure.forget();
}
}