Scene example: write file in a task (#5952)

# Objective

- Fix #5951 
- Improve on #5949 by not risking blocking a system

## Solution

- Wrap file writing in a task
This commit is contained in:
François 2022-09-12 12:19:40 +00:00
parent 404b4fc0eb
commit 1b9720526e

View file

@ -2,7 +2,7 @@
use std::fs::File;
use std::io::Write;
use bevy::{prelude::*, utils::Duration};
use bevy::{prelude::*, tasks::IoTaskPool, utils::Duration};
fn main() {
App::new()
@ -104,17 +104,23 @@ fn save_scene_system(world: &mut World) {
let scene = DynamicScene::from_world(&scene_world, type_registry);
// Scenes can be serialized like this:
info!("{}", scene.serialize_ron(type_registry).unwrap());
let serialized_scene = scene.serialize_ron(type_registry).unwrap();
// Write the scene RON data to file (leveraging From<io::Error> for ron::error::Error)
File::create(format!("assets/{}", NEW_SCENE_FILE_PATH))
.map_err(|err| err.into())
.and_then(|mut file| {
scene
.serialize_ron(type_registry)
.and_then(|data| file.write(data.as_bytes()).map_err(|err| err.into()))
// Showing the scene in the console
info!("{}", serialized_scene);
// Writing the scene to a new file. Using a task to avoid calling the filesystem APIs in a system
// as they are blocking
// This can't work in WASM as there is no filesystem access
#[cfg(not(target_arch = "wasm32"))]
IoTaskPool::get()
.spawn(async move {
// Write the scene RON data to file
File::create(format!("assets/{}", NEW_SCENE_FILE_PATH))
.and_then(|mut file| file.write(serialized_scene.as_bytes()))
.expect("Error while writing scene to file");
})
.expect("Error while writing scene to file");
.detach();
}
// This is only necessary for the info message in the UI. See examples/ui/text.rs for a standalone