1681-engine / index / AssetLoader

Class: AssetLoader

Defined in: src/assets/AssetLoader.ts:133

Loads a scene's assets before it starts: queue them, then await load(). Images become textures in the stage's registry (frames of a sprite sheet named 0, 1, 2…); JSON, text and Tiled maps are kept here by key; atlases register every frame under their key; fonts go to document.fonts; audio is decoded into AudioBuffers (or kept as bytes until a context exists). A failed asset fails the whole load with its URL in the message.

override async onEnter() {
  const assets = new AssetLoader(this.engine.stage.textures);
  assets.spritesheet('hero', 'art/hero.png', { frameWidth: 20, frameHeight: 24 }).tilemap('level', 'maps/level.tmj');
  await assets.load(({ done, total }) => bar.set(done / total));
  const map = assets.map('level');
}

Constructors

Constructor

new AssetLoader(textures, options?): AssetLoader;

Defined in: src/assets/AssetLoader.ts:148

Parameters

Parameter	Type
textures	TextureSink
options	AssetLoaderOptions

Returns

AssetLoader

Methods

atlas()

atlas(key, url): this;

Defined in: src/assets/AssetLoader.ts:222

A TexturePacker (or Pixi) JSON atlas, hash or array format: its page image, and for a multipack atlas every page named in meta.related_multi_packs (each resolved beside the file naming it). The first page is the texture key, further pages key~1, key~2…, and every frame of every page is found as textures.get(key, frameName). Counts as one asset in the progress.

Parameters

Parameter	Type
key	string
url	string

Returns

this

---

audio()

audio(key, url): this;

Defined in: src/assets/AssetLoader.ts:263

A sound file decoded into an AudioBuffer through the engine's audio context (getAudio). Before any context exists (browsers open one only after a gesture) the bytes are kept and decoded by decodeAudio, so a loading screen never has to wait for the player to click.

Parameters

Parameter	Type
key	string
url	string

Returns

this

---

decodeAudio()

decodeAudio(key, ctx?): Promise<AudioBuffer>;

Defined in: src/assets/AssetLoader.ts:283

A loaded sound, decoding its kept bytes through ctx (default: the loader's context) the first time.

Parameters

Parameter	Type
key	string
ctx?	BaseAudioContext

Returns

Promise<AudioBuffer>

---

font()

font(
   family, 
   url, 
   descriptors?
): this;

Defined in: src/assets/AssetLoader.ts:245

A web font (woff2, woff, ttf) under family, added to document.fonts once loaded so canvas text and the DOM can use it at once — load fonts before the first Text is drawn, or it measures with the fallback.

Parameters

Parameter	Type
family	string
url	string
descriptors?	FontFaceDescriptors

Returns

this

---

getAtlas()

getAtlas(key): AtlasInfo;

Defined in: src/assets/AssetLoader.ts:309

What a loaded atlas holds: its frame names and animations.

Parameters

Parameter	Type
key	string

Returns

AtlasInfo

---

getAudio()

getAudio(key): AudioBuffer | null;

Defined in: src/assets/AssetLoader.ts:275

A loaded sound, decoded; null while it waits for an audio context (decodeAudio).

Parameters

Parameter	Type
key	string

Returns

AudioBuffer | null

---

getJson()

getJson<T>(key): T;

Defined in: src/assets/AssetLoader.ts:330

A loaded JSON value.

Type Parameters

Type Parameter	Default type
T	unknown

Parameters

Parameter	Type
key	string

Returns

T

---

getText()

getText(key): string;

Defined in: src/assets/AssetLoader.ts:336

A loaded text file.

Parameters

Parameter	Type
key	string

Returns

string

---

image()

image(key, url): this;

Defined in: src/assets/AssetLoader.ts:156

Parameters

Parameter	Type
key	string
url	string

Returns

this

---

json()

json(key, url): this;

Defined in: src/assets/AssetLoader.ts:169

Parameters

Parameter	Type
key	string
url	string

Returns

this

---

ldtk()

ldtk(
   key, 
   url, 
   options?
): this;

Defined in: src/assets/AssetLoader.ts:196

An LDtk project: the .ldtk file, the .ldtkl file of each level it saves apart (resolved beside the project), then every tileset image (resolved beside the project, as LDtk writes relPath). Counts as one asset, plus one per tileset image. Read it back with ldtkProject(key); each level's map goes to TilemapView as it is.

Parameters

Parameter	Type
key	string
url	string
options	LdtkAssetOptions

Returns

this

---

ldtkProject()

ldtkProject(key): LdtkProject;

Defined in: src/assets/AssetLoader.ts:210

A loaded LDtk project.

Parameters

Parameter	Type
key	string

Returns

LdtkProject

---

load()

load(onProgress?): Promise<void>;

Defined in: src/assets/AssetLoader.ts:316

Runs everything queued; onProgress after each asset. Safe to call again after queueing more.

Parameters

Parameter	Type
onProgress?	(p) => void

Returns

Promise<void>

---

map()

map(key): TileMap;

Defined in: src/assets/AssetLoader.ts:341

A loaded Tiled map.

Parameters

Parameter	Type
key	string

Returns

TileMap

---

spritesheet()

spritesheet(
   key, 
   url, 
   size
): this;

Defined in: src/assets/AssetLoader.ts:163

An image cut into equal frames named 0, 1, 2…, left to right, then row by row.

Parameters

Parameter	Type
key	string
url	string
size	{ frameHeight: number; frameWidth: number; }
size.frameHeight	number
size.frameWidth	number

Returns

this

---

text()

text(key, url): this;

Defined in: src/assets/AssetLoader.ts:175

Parameters

Parameter	Type
key	string
url	string

Returns

this

---

tilemap()

tilemap(
   key, 
   url, 
   options?
): this;

Defined in: src/assets/AssetLoader.ts:182

A Tiled JSON map, then every tileset image it names (resolved beside the map file).

Parameters

Parameter	Type
key	string
url	string
options	TilemapAssetOptions

Returns

this