Loads a glTF asset from TCP streams?

[wbpaley]

First post here; gotta say Bevy is amazing! You guys rock.
Been waiting/hoping for something (open, rigorous) like this for a decade.

I want to populate a 3d Bevy world with assets coming in over a TCP connection from another app where they're created on the fly.

I already have the asset in a String, and hacked by writing it out as a file; this works to read it back in:

commands.spawn(SceneBundle {
    scene: asset_server.load("../assets/models/tmp/foo.gltf#Scene0"),
    ..default()
});

Is there anything like asset_server.load([String]) that loads directly from the String (not using it as a path to a file)?

(Got excited for a moment about https://github.com/vleue/bevy_embedded_assets, but lack the temerity to figure out if it's done somewhere in there... ; )

[TimJentzsch]

With the new Assets V2 system, I think your best shot is to implement a custom AssetSource which uses TCP to read the assets from the other app.
The documentation still seems to be a bit sparse, but the Bevy 0.12 announcement post gives an introduction on this topic.

From what I understand you would need to implement a custom AssetReader and then configure a new AssetSource to use that reader.

Then you could do something like

commands.spawn(SceneBundle {
    scene: asset_server.load("tcp://../assets/models/tmp/foo.gltf#Scene0"),
    ..default()
});

Maybe the FileAssetReader can serve as reference.

Hope that helps :)

[rlidwka]

Here's an example for you (loads glTF asset directly from github):

use std::path::Path;
use std::str::FromStr;
use std::time::Duration;

use bevy::asset::io::{AssetReader, AssetReaderError, AssetSource, PathStream, Reader};
use bevy::prelude::*;
use bevy::utils::BoxedFuture;
use isahc::config::{Configurable, RedirectPolicy};
use isahc::http::Uri;
use isahc::HttpClient;

const PROTO_HTTP:  u8 = 0;
const PROTO_HTTPS: u8 = 1;

struct HttpAssetReader<const PROTO: u8>(HttpClient);

impl<const PROTO: u8> AssetReader for HttpAssetReader<PROTO> {
    fn read<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<Box<Reader<'a>>, AssetReaderError>> {
        Box::pin(async move {
            let proto = match PROTO {
                PROTO_HTTP  => "http",
                PROTO_HTTPS => "https",
                _ => unreachable!(),
            };

            let uri = (|| { Uri::from_str(&format!("{}://{}", proto, path.to_str()?)).ok() })();
            let Some(uri) = uri else {
                return Err(std::io::Error::new(std::io::ErrorKind::InvalidInput, "invalid path").into());
            };

            let response = match self.0.get_async(uri).await {
                Ok(response) => response,
                Err(err) => {
                    let err: std::io::Error = err.into();
                    return Err(err.into());
                }
            };

            if !response.status().is_success() {
                return Err(std::io::Error::new(std::io::ErrorKind::NotFound, response.status().to_string()).into());
            }

            let body = response.into_body();
            let reader: Box<Reader> = Box::new(body);
            Ok(reader)
        })
    }

    fn read_meta<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<Box<Reader<'a>>, AssetReaderError>> {
        Box::pin(async move { Err(AssetReaderError::NotFound(path.to_path_buf())) })
    }

    fn read_directory<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<Box<PathStream>, AssetReaderError>> {
        Box::pin(async move { Err(AssetReaderError::NotFound(path.to_path_buf())) })
    }

    fn is_directory<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<bool, AssetReaderError>> {
        Box::pin(async move { Err(AssetReaderError::NotFound(path.to_path_buf())) })
    }
}

#[allow(clippy::redundant_clone)]
fn main() {
    let client = HttpClient::builder()
        .max_connections(10)
        .max_connections_per_host(10)
        .tcp_keepalive(Duration::from_secs(10))
        .redirect_policy(RedirectPolicy::Follow)
        .build()
        .unwrap();

    App::new()
        .register_asset_source("http",  AssetSource::build().with_reader({
            let client = client.clone();
            move || Box::new(HttpAssetReader::<PROTO_HTTP>(client.clone()))
        }))
        .register_asset_source("https",  AssetSource::build().with_reader({
            let client = client.clone();
            move || Box::new(HttpAssetReader::<PROTO_HTTPS>(client.clone()))
        }))
        .add_plugins(DefaultPlugins)
        .add_systems(Startup, setup)
        .add_systems(Update, bevy::window::close_on_esc)
        .run();
}

fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
    commands.spawn(Camera3dBundle {
        transform: Transform::from_xyz(0.7, 0.7, 1.).looking_at(Vec3::new(0.0, 0.3, 0.0), Vec3::Y),
        ..default()
    });
    commands.spawn(DirectionalLightBundle::default());
    commands.spawn(SceneBundle {
        scene: asset_server.load("https://github.com/bevyengine/bevy/raw/main/assets/models/AlienCake/cakeBirthday.glb#Scene0"),
        ..default()
    });
}

[wbpaley]

Wow, thanks! I will check this out early tomorrow. .

…

On Jan 5, 2024 at 8:54 PM -0800, Alex Kocharin ***@***.***>, wrote: Here's an example for you (loads glTF asset directly from github): use std::path::Path; use std::str::FromStr; use std::time::Duration; use bevy::asset::io::{AssetReader, AssetReaderError, AssetSource, PathStream, Reader}; use bevy::prelude::*; use bevy::utils::BoxedFuture; use isahc::config::{Configurable, RedirectPolicy}; use isahc::http::Uri; use isahc::HttpClient; const PROTO_HTTP: u8 = 0; const PROTO_HTTPS: u8 = 1; struct HttpAssetReader<const PROTO: u8>(HttpClient); impl<const PROTO: u8> AssetReader for HttpAssetReader<PROTO> { fn read<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<Box<Reader<'a>>, AssetReaderError>> { Box::pin(async move { let proto = match PROTO { PROTO_HTTP => "http", PROTO_HTTPS => "https", _ => unreachable!(), }; let uri = (|| { Uri::from_str(&format!("{}://{}", proto, path.to_str()?)).ok() })(); let Some(uri) = uri else { return Err(std::io::Error::new(std::io::ErrorKind::InvalidInput, "invalid path").into()); }; let response = match self.0.get_async(uri).await { Ok(response) => response, Err(err) => { let err: std::io::Error = err.into(); return Err(err.into()); } }; if !response.status().is_success() { return Err(std::io::Error::new(std::io::ErrorKind::NotFound, response.status().to_string()).into()); } let body = response.into_body(); let reader: Box<Reader> = Box::new(body); Ok(reader) }) } fn read_meta<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<Box<Reader<'a>>, AssetReaderError>> { Box::pin(async move { Err(AssetReaderError::NotFound(path.to_path_buf())) }) } fn read_directory<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<Box<PathStream>, AssetReaderError>> { Box::pin(async move { Err(AssetReaderError::NotFound(path.to_path_buf())) }) } fn is_directory<'a>(&'a self, path: &'a Path) -> BoxedFuture<'a, Result<bool, AssetReaderError>> { Box::pin(async move { Err(AssetReaderError::NotFound(path.to_path_buf())) }) } } #[allow(clippy::redundant_clone)] fn main() { let client = HttpClient::builder() .max_connections(10) .max_connections_per_host(10) .tcp_keepalive(Duration::from_secs(10)) .redirect_policy(RedirectPolicy::Follow) .build() .unwrap(); App::new() .register_asset_source("http", AssetSource::build().with_reader({ let client = client.clone(); move || Box::new(HttpAssetReader::<PROTO_HTTP>(client.clone())) })) .register_asset_source("https", AssetSource::build().with_reader({ let client = client.clone(); move || Box::new(HttpAssetReader::<PROTO_HTTPS>(client.clone())) })) .add_plugins(DefaultPlugins) .add_systems(Startup, setup) .add_systems(Update, bevy::window::close_on_esc) .run(); } fn setup(mut commands: Commands, asset_server: Res<AssetServer>) { commands.spawn(Camera3dBundle { transform: Transform::from_xyz(0.7, 0.7, 1.).looking_at(Vec3::new(0.0, 0.3, 0.0), Vec3::Y), ..default() }); commands.spawn(DirectionalLightBundle::default()); commands.spawn(SceneBundle { scene: asset_server.load("https://github.com/bevyengine/bevy/raw/main/assets/models/AlienCake/cakeBirthday.glb#Scene0"), ..default() }); } — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>