|bevy vewsion:|0.9 |(outdated!)| |---|---|---|

As this page is outdated, please refer to Bevy's official migration guides while reading, to cover the differences: 0.9 to 0.10, 0.10 to 0.11, 0.11 to 0.12, 0.12 to 0.13, 0.13 to 0.14.

I apologize for the inconvenience. I will update the page as soon as I find the time.

woad assets fwom fiwes with assetsewvew

wewevant officiaw exampwes: asset_loading.

to woad assets fwom fiwes, >_< use the AssetServer wesouwce.

#[dewive(wesouwce)]
stwuct uifont(handwe<font>);

fn woad_ui_font(
    m-mut commands: c-commands, σωσ
    s-sewvew: wes<assetsewvew>
) {
    w-wet handwe: handwe<font> = s-sewvew.woad("font.ttf");

    // we c-can stowe the h-handwe in a wesouwce:
    //  - t-to pwevent the asset fwom being unwoaded
    //  - if we want to use it to access t-the asset watew
    commands.insewt_wesouwce(uifont(handwe));
}

this queues the asset woading to h-happen in the backgwound, OwO a-and wetuwn a-a handwe. ^•ﻌ•^ the asset wiww take some time to b-become avaiwabwe. OwO y-you cannot access the actuaw data immediatewy i-in the s-same system, but you can use the handwe.

you can spawn entities wike youw 2d s-spwites, OwO 3d modews, 🥺 a-and ui, òωó using t-the handwe, OwO even befowe the asset has w-woaded. 🥺 they wiww j-just "pop in" w-watew, when the asset becomes weady.

note that it is ok to caww asset_server.load(…) as many times as you want, even if the asset is cuwwentwy woading, OwO o-ow awweady w-woaded. 🥺 it wiww j-just pwovide you with the same handwe. OwO e-evewy time you c-caww it, 🥺 it wiww j-just check the status of the asset, OwO begin woading i-it if nyeeded, 🥺 a-and give you a-a handwe.

bevy suppowts woading a vawiety of asset fiwe fowmats, and can be extended to suppowt mowe. OwO t-the asset woadew i-impwementation t-to use is sewected based on the fiwe extension.

untyped woading

if you want an untyped handwe, XD you can use asset_server.load_untyped(…) instead.

untyped woading is possibwe, OwO because b-bevy awways d-detects the fiwe t-type fwom the fiwe extension anyway.

woading fowdews

you can awso woad an entiwe fowdew o-of assets, ^•ﻌ•^ wegawdwess o-of how many fiwes awe inside, >< using asset_server.load_folder(…). >< this gives you a Vec<HandleUntyped> with aww the untyped handwes.

#[dewive(wesouwce)]
stwuct extwaassets(vec<handweuntyped>);

fn woad_extwa_assets(
    m-mut commands: c-commands, òωó
    s-sewvew: wes<assetsewvew>, o.O
) {
    i-if wet ok(handwes) = s-sewvew.woad_fowdew("extwa") {
        commands.insewt_wesouwce(extwaassets(handwes));
    }
}

woading fowdews is nyot suppowted b-by aww i/o backends. OwO n-nyotabwy, 🥺 i-it does nyot wowk on wasm/web.

assetpath and wabews

the asset path you use to identify a-an asset fwom t-the fiwesystem is a-actuawwy a speciaw AssetPath, >_< which consists of the fiwe path + a wabew. OwO wabews awe used in situations w-whewe muwtipwe a-assets awe c-contained in the same fiwe. (ꈍᴗꈍ) an exampwe of this a-awe gwtf fiwes, XD which can contain meshes, (ꈍᴗꈍ) scenes, ^•ﻌ•^ textuwes, OwO m-matewiaws, etc.

asset paths can be cweated fwom a s-stwing, OwO with the w-wabew (if any) a-attached aftew a # symbow.

fn woad_gwtf_things(
    mut commands: c-commands, rawr
    s-sewvew: wes<assetsewvew>
) {
    // g-get a specific m-mesh
    w-wet my_mesh: handwe<mesh> = s-sewvew.woad("my_scene.gwtf#mesh0/pwimitive0");

    // s-spawn a whowe s-scene
    wet my_scene: handwe<scene> = sewvew.woad("my_scene.gwtf#scene0");
    commands.spawn(scenebundwe {
        scene: my_scene, σωσ
        ..defauwt::defauwt()
    });
}

see the gwtf page fow mowe info about wowking with 3d m-modews.

whewe awe assets woaded fwom?

the asset sewvew intewnawwy wewies o-on an impwementation o-of the AssetIo wust twait, (ꈍᴗꈍ) which is bevy's way o-of pwoviding "backends" fow fetching data fwom d-diffewent types o-of stowage.

bevy pwovides its own defauwt buiwt-in i-i/o backends f-fow each suppowted pwatfowm.

on desktop pwatfowms, OwO it tweats asset p-paths as wewative t-to a fowdew c-cawwed assets, (ꈍᴗꈍ) that must be pwaced at one of the f-fowwowing wocations:

  • awongside the game's executabwe fiwe, (ꈍᴗꈍ) f-fow distwibution
  • in youw cawgo pwoject fowdew, ^•ﻌ•^ when w-wunning youw game u-using cargo duwing devewopment
    • this is identified by the CARGO_MANIFEST_DIR enviwonment vawiabwe

on the web, ^•ﻌ•^ it fetches assets using h-http uwws pointing w-within an assets fowdew wocated awongside the game's .wasm fiwe.

thewe awe unofficiaw pwugins avaiwabwe that pwovide awtewnative i/o backend impwementations, OwO such a-as fow woading a-assets fwom inside a-awchive fiwes (.zip), ^•ﻌ•^ embedded inside the game executabwe, OwO u-using a netwowk p-pwotocow, … many othew possibiwities.