Allow using animated entities as map tiles

A more optimized implementation for animated tiles is planned.

src/view/map.ts

@@ -1,3 +1,4 @@
+import { EntityView } from './entity';
 import { Renderer } from './renderer/renderer';
 import { SpriteCoords, SpriteView, SpriteViewBuilder } from './sprite';
 import { loadImage, mkTexture } from './util/image';
@@ -6,39 +7,91 @@ import { MapData } from '../model/data/map';
 
 import { nextPowerOf2 } from '../util';
 
-interface Tileset {
-	texture: WebGLTexture;
-	tiles: SpriteCoords[];
+import { vec2 } from 'gl-matrix';
+
+interface StaticMapTile {
+	type: 'static';
+	image: HTMLImageElement;
 }
 
-function loadTiles(tiles: string[]): Promise<HTMLImageElement[]> {
-	return Promise.all(tiles.map((t) => loadImage(`resources/sprite/tile/${t}.png`)));
+interface EntityTile {
+	type: 'entity';
+	entity: EntityView;
+}
+
+type MapTile = StaticMapTile | EntityTile;
+
+interface StaticTilesetTile {
+	type: 'static';
+	coords: SpriteCoords;
+}
+
+type TilesetTile = StaticTilesetTile | EntityTile;
+
+interface Tileset {
+	texture: WebGLTexture;
+	tiles: TilesetTile[];
+}
+
+async function loadTile(r: Renderer, tile: string): Promise<MapTile> {
+	const name = tile.substr(1);
+	switch (tile[0]) {
+	case '-':
+		return {
+			type: 'static',
+			image: await loadImage(`resources/sprite/tile/${name}.png`),
+		};
+
+	case '@':
+		return {
+			type: 'entity',
+			entity: await EntityView.load(r, name),
+		};
+
+	default:
+		throw new Error('invalid tile specifier');
+	}
+}
+
+function loadTiles(r: Renderer, tiles: string[]): Promise<MapTile[]> {
+	return Promise.all(tiles.map((tile) => loadTile(r, tile)));
 }
 
 function mkTileset(
 	r: Renderer,
-	tiles: HTMLImageElement[],
+	mapTiles: MapTile[],
 ): Tileset {
 	const tileSize = 32;
 
-	const canvasDim = nextPowerOf2(Math.sqrt(tiles.length));
+	const canvasDim = nextPowerOf2(Math.sqrt(mapTiles.length));
 	const canvasSize = canvasDim * tileSize;
 
 	const canvas = document.createElement('canvas');
 	canvas.width = canvas.height = canvasSize;
 
 	let x = 0, y = 0;
-	const tileCoords: SpriteCoords[] = [];
+	const tiles: TilesetTile[] = [];
 	const ctx = canvas.getContext('2d') as CanvasRenderingContext2D;
 
-	for (const tile of tiles) {
-		ctx.drawImage(tile, x * tileSize, y * tileSize);
-		tileCoords.push([x / canvasDim, y / canvasDim, (x + 1) / canvasDim, (y + 1) / canvasDim]);
+	for (const tile of mapTiles) {
+		switch (tile.type) {
+		case 'static':
+			ctx.drawImage(tile.image, x * tileSize, y * tileSize);
+			tiles.push({
+				type: 'static',
+				coords: [x / canvasDim, y / canvasDim, (x + 1) / canvasDim, (y + 1) / canvasDim],
+			});
 
-		x++;
-		if (x === canvasDim) {
-			x = 0;
-			y++;
+			x++;
+			if (x === canvasDim) {
+				x = 0;
+				y++;
+			}
+			break;
+
+		case 'entity':
+			tiles.push(tile);
+			break;
 		}
 	}
 
@@ -46,40 +99,66 @@ function mkTileset(
 
 	return {
 		texture,
-		tiles: tileCoords,
+		tiles,
 	};
 }
 
-function addSprite(builder: SpriteViewBuilder, tileset: Tileset, x: number, y: number, tile: number) {
-	if (tile === 0)
+function addSprite(
+	builder: SpriteViewBuilder,
+	entityTiles: Array<[[number, number], EntityView]>,
+	tileset: Tileset,
+	x: number,
+	y: number,
+	tile: number) {
+	if (!tile)
 		return;
 
-	const tilePos = tileset.tiles[tile - 1];
-	builder.addSprite([x, y, x + 1, y + 1], tilePos);
+	const tilesetTile = tileset.tiles[tile - 1];
+
+	switch (tilesetTile.type) {
+		case 'static':
+			builder.addSprite([x, y, x + 1, y + 1], tilesetTile.coords);
+			break;
+
+		case 'entity':
+			entityTiles.push([[x + 0.5, y + 0.5], tilesetTile.entity]);
+			break;
+	}
 }
 
 function buildMapLayer(r: Renderer, tileset: Tileset, layer: number[][]): MapLayerView {
 	const builder = new SpriteViewBuilder(r, tileset.texture);
+	const entityTiles: Array<[[number, number], EntityView]> = [];
 
 	for (let x = 0; x < layer[0].length; x++)
 		for (let y = 0; y < layer.length; y++)
-			addSprite(builder, tileset, x, y, layer[y][x]);
+			addSprite(builder, entityTiles, tileset, x, y, layer[y][x]);
 
-	return new MapLayerView(builder.build());
+	return new MapLayerView(r, builder.build(), entityTiles);
 }
 
 class MapLayerView {
-	public constructor(private sprites: SpriteView) {
+	public constructor(
+		private r: Renderer,
+		private staticTiles: SpriteView,
+		private entityTiles: Array<[[number, number], EntityView]>,
+	) {
 	}
 
 	public render(time: number): void {
-		this.sprites.render();
+		this.r.setTranslation([0, 0]);
+		this.staticTiles.render();
+
+		for (const [coords, entity] of this.entityTiles) {
+			this.r.setTranslation(coords);
+			entity.renderByTime(time);
+		}
 	}
 }
 
 export class MapView {
 	public static async load(r: Renderer, map: MapData): Promise<MapView> {
-		const tiles = await loadTiles(map.tiles);
+		const tiles = await loadTiles(r, map.tiles);
 		const tileset = mkTileset(r, tiles);
 
 		const layers = map.layers.map((layer) => buildMapLayer(r, tileset, layer.tiles));