Struct AssetNodeResolved

Source

pub struct AssetNodeResolved<'a, T: Component> { /* private fields */ }

Expand description

AssetNodeResolved represents a resolved asset node, providing access to the component associated with the asset. It allows both read and write access to the component, ensuring that the asset is properly resolved before accessing its data.

Implementations§

Source §

impl<'a, T: Component> AssetNodeResolved<'a, T>

Source

pub fn read(&self) -> Option<&T>

Gives read access to component of the asset.

§Returns

An Option containing a reference to the component if it is accessible, or None if the component is not accessible.

Source

pub fn write(&self) -> Option<&mut T>

Gives write access to component of the asset.

§Returns

An Option containing a mutable reference to the component if it is accessible, or None if the component is not accessible.

Source

pub fn read_unchecked(&self) -> &T

Gives unchecked read access to component of the asset.

§Returns

A reference to the component, allowing read access without checking if the component is accessible. This method can panic if the component is not accessible, so it should be used with caution.

Examples found in repository ?

examples/hello_graph.rs (line 41)

14fn main() -> Result<(), Box<dyn Error>> {
15    // /* ANCHOR: main */
16    let mut database = AssetDatabase::default()
17        .with_protocol(BundleAssetProtocol::new(
18            "custom",
19            // AssetTreeProcessor handles deserialization of the custom asset
20            // as single component. That component will report its dependencies
21            // to load.
22            AssetTreeProcessor::<CustomAsset>::new(|bytes| {
23                Ok(serde_json::from_slice::<CustomAsset>(&bytes)?)
24            }),
25        ))
26        .with_fetch(FileAssetFetch::default().with_root("resources"));
27
28    // Create asset node and ensure it is being loaded.
29    let asset = AssetNode::<CustomAsset>::new("custom://part1.json");
30    asset.ensure(&mut database)?;
31
32    // Wait until the database is not busy, which means all assets are loaded.
33    while database.is_busy() {
34        database.maintain()?;
35    }
36
37    // Resolve the asset and read its contents.
38    // This will also resolve all dependencies of the asset.
39    let contents = asset
40        .resolve(&database)?
41        .read_unchecked()
42        .contents(&database);
43    println!("Custom chain contents: {contents:?}");
44    // /* ANCHOR_END: main */
45    Ok(())
46}
47
48/* ANCHOR: custom_asset */
49// This example demonstrates how to create a custom asset type that can
50// have dependencies on other assets. The `CustomAsset` struct is defined
51// with a `content` field and an optional `next` field that points to another
52// `CustomAsset`.
53#[derive(Debug, Default, Serialize, Deserialize, AssetTree)]
54struct CustomAsset {
55    content: String,
56    // The `next` field is annotated with `#[asset_deps]` to indicate that it is
57    // an asset dependency that has to be loaded along with this asset.
58    #[serde(default)]
59    #[asset_deps]
60    next: Option<AssetNode<CustomAsset>>,
61}
62
63impl CustomAsset {
64    fn contents(&self, database: &AssetDatabase) -> String {
65        let mut result = self.content.as_str().to_owned();
66        if let Some(next) = self.next.as_ref() {
67            result.push(' ');
68            if let Ok(resolved) = next.resolve(database) {
69                result.push_str(&resolved.read_unchecked().contents(database));
70            }
71        }
72        result
73    }

Source

pub fn write_unchecked(&self) -> &mut T

Gives unchecked write access to component of the asset.

§Returns

A mutable reference to the component, allowing write access without checking if the component is accessible. This method can panic if the component is not accessible, so it should be used with caution.