view: refactor generic parts of MapView into a TileView

3 files changed, 101 insertions, 61 deletions

diff --git a/src/view/MapLoader.ts b/src/view/MapLoader.ts
index 878fef4..a35eeec 100644
--- a/src/view/MapLoader.ts
+++ b/src/view/MapLoader.ts
@@ -1,4 +1,6 @@
-import {mapValues, mapValuesAsync, nextPowerOf2} from '../util';
+import { mapValues, mapValuesAsync, nextPowerOf2 } from '../util';
+
+import { TileCoords } from './tile';
 
 import MapState from '../model/state/MapState';
 import MapView from './MapView';
@@ -6,7 +8,7 @@ import Renderer from './renderer/Renderer';
 
 export interface TileMap {
 	texture: WebGLTexture;
-	tiles: Map<string, [number, number, number, number]>;
+	tiles: Map<string, TileCoords>;
 }
 
 function loadImage(url: string): Promise<HTMLImageElement> {
@@ -54,7 +56,7 @@ function mkTileMap(
 	canvas.width = canvas.height = canvasSize;
 
 	let x = 0, y = 0;
-	const map: Map<string, [number, number, number, number]> = new Map();
+	const map: Map<string, TileCoords> = new Map();
 	const ctx = canvas.getContext('2d') as CanvasRenderingContext2D;
 
 	for (const [k, tile] of tiles) {
diff --git a/src/view/MapView.ts b/src/view/MapView.ts
index 1061196..a5af8f7 100644
--- a/src/view/MapView.ts
+++ b/src/view/MapView.ts
@@ -1,74 +1,38 @@
 import MapState from '../model/state/MapState';
-import {TileMap} from './MapLoader';
+import { TileMap } from './MapLoader';
 import Renderer from './renderer/Renderer';
+import { TileView, TileViewBuilder } from './tile';
 
 export default class MapView {
-	private readonly vertexBuffer: WebGLBuffer;
-	private readonly textureBuffer: WebGLBuffer;
+	private static addTile(builder: TileViewBuilder, tileMap: TileMap, x: number, y: number, tile: string) {
+		if (tile === ' ')
+			return;
+
+		const tilePos = tileMap.tiles.get(tile);
+		if (!tilePos)
+			throw new Error('invalid tile specifier in map data');
+
+		builder.addTile([x, y, x + 1, y + 1], tilePos);
+	}
+
+	private readonly tileView: TileView;
 
 	constructor(
-		private readonly r: Renderer,
-		private readonly map: MapState,
-		private readonly tileMap: TileMap,
+		r: Renderer,
+		map: MapState,
+		tileMap: TileMap,
 	) {
-		const vertexData: number[] = [];
-		const textureData: number[] = [];
+		const builder = new TileViewBuilder(r, tileMap.texture);
 
 		for (let x = 0; x < map.data.width; x++)
 			for (let y = 0; y < map.data.height; y++)
 				for (const layer of map.data.layers)
-					this.addTile(vertexData, textureData, x, y, layer[y][x]);
-
-		const gl = r.getContext();
+					MapView.addTile(builder, tileMap, x, y, layer[y][x]);
 
-		this.vertexBuffer = r.createBuffer();
-		gl.bindBuffer(gl.ARRAY_BUFFER, this.vertexBuffer);
-		gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(vertexData), gl.STATIC_DRAW);
-
-		this.textureBuffer = r.createBuffer();
-		gl.bindBuffer(gl.ARRAY_BUFFER, this.textureBuffer);
-		gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(textureData), gl.STATIC_DRAW);
+		this.tileView = builder.build();
 	}
 
-	public draw(): void {
-		const gl = this.r.getContext();
-
-		gl.clear(gl.COLOR_BUFFER_BIT);
-
-		gl.activeTexture(gl.TEXTURE0);
-		gl.bindTexture(gl.TEXTURE_2D, this.tileMap.texture);
-		gl.uniform1i(this.r.getSamplerLoc(), 0);
-
-		gl.bindBuffer(gl.ARRAY_BUFFER, this.vertexBuffer);
-		gl.vertexAttribPointer(this.r.getVertexPosLoc(), 2, gl.FLOAT, false, 0, 0);
-
-		gl.bindBuffer(gl.ARRAY_BUFFER, this.textureBuffer);
-		gl.vertexAttribPointer(this.r.getTextureCoordLoc(), 2, gl.FLOAT, false, 0, 0);
-
-		gl.drawArrays(gl.TRIANGLES, 0, 6 * this.map.data.width * this.map.data.height);
-	}
-
-	private pushTile(buf: number[], coords: [number, number, number, number]) {
-		const [x1, y1, x2, y2] = coords;
-
-		buf.push(x1); buf.push(y1);
-		buf.push(x2); buf.push(y1);
-		buf.push(x1); buf.push(y2);
-
-		buf.push(x1); buf.push(y2);
-		buf.push(x2); buf.push(y1);
-		buf.push(x2); buf.push(y2);
-	}
-
-	private addTile(vertexData: number[], textureData: number[], x: number, y: number, tile: string) {
-		if (tile === ' ')
-			return;
-
-		const tilePos = this.tileMap.tiles.get(tile);
-		if (!tilePos)
-			throw new Error('invalid tile specifier in map data');
-
-		this.pushTile(vertexData, [x, y, x + 1, y + 1]);
-		this.pushTile(textureData, tilePos);
+	public render(): void {
+		this.tileView.render();
 	}
 }
diff --git a/src/view/tile.ts b/src/view/tile.ts
new file mode 100644
index 0000000..d748ec9
--- /dev/null
+++ b/src/view/tile.ts
@@ -0,0 +1,74 @@
+import Renderer from './renderer/Renderer';
+
+export type TileCoords = [number, number, number, number];
+
+export class TileViewBuilder {
+	private static pushTile(buf: number[], coords: TileCoords): void {
+		const [x1, y1, x2, y2] = coords;
+
+		buf.push(x1); buf.push(y1);
+		buf.push(x2); buf.push(y1);
+		buf.push(x1); buf.push(y2);
+
+		buf.push(x1); buf.push(y2);
+		buf.push(x2); buf.push(y1);
+		buf.push(x2); buf.push(y2);
+	}
+
+	private readonly vertexData: number[] = [];
+	private readonly textureData: number[] = [];
+
+	constructor(private readonly r: Renderer, private readonly texture: WebGLTexture) {}
+
+	public addTile(vertexCoords: TileCoords, texCoords: TileCoords): void {
+		TileViewBuilder.pushTile(this.vertexData, vertexCoords);
+		TileViewBuilder.pushTile(this.textureData, texCoords);
+	}
+
+	public build(): TileView {
+		return new TileView(this.r, this.texture, this.vertexData, this.textureData);
+	}
+}
+
+export class TileView {
+	private readonly primitiveCount: number;
+	private readonly vertexBuffer: WebGLBuffer;
+	private readonly textureBuffer: WebGLBuffer;
+
+	constructor(
+		private readonly r: Renderer,
+		private readonly texture: WebGLTexture,
+		vertexData: number[],
+		textureData: number[],
+	) {
+		const gl = r.getContext();
+
+		this.vertexBuffer = r.createBuffer();
+		gl.bindBuffer(gl.ARRAY_BUFFER, this.vertexBuffer);
+		gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(vertexData), gl.STATIC_DRAW);
+
+		this.textureBuffer = r.createBuffer();
+		gl.bindBuffer(gl.ARRAY_BUFFER, this.textureBuffer);
+		gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(textureData), gl.STATIC_DRAW);
+
+		this.primitiveCount = vertexData.length / 3;
+	}
+
+	public render(): void {
+		const gl = this.r.getContext();
+
+		gl.clear(gl.COLOR_BUFFER_BIT);
+
+		gl.activeTexture(gl.TEXTURE0);
+		gl.bindTexture(gl.TEXTURE_2D, this.texture);
+		gl.uniform1i(this.r.getSamplerLoc(), 0);
+
+		gl.bindBuffer(gl.ARRAY_BUFFER, this.vertexBuffer);
+		gl.vertexAttribPointer(this.r.getVertexPosLoc(), 2, gl.FLOAT, false, 0, 0);
+
+		gl.bindBuffer(gl.ARRAY_BUFFER, this.textureBuffer);
+		gl.vertexAttribPointer(this.r.getTextureCoordLoc(), 2, gl.FLOAT, false, 0, 0);
+
+		gl.drawArrays(gl.TRIANGLES, 0, this.primitiveCount);
+	}
+}