added level 4, which introduces the player to holes

Makefile

@@ -1,30 +1,21 @@
 .PHONY: all clean
 
+IMAGES = $(foreach name, apple wall, public/assets/$(name)32.png)
+TILESETS = $(foreach name, hole, public/assets/$(name)-ts.png)
+JSON = $(foreach name, snake levelList config, public/assets/$(name).json)
 ICON = public/assets/icon32.png public/assets/icon256.png public/favicon.ico
-APPLE = public/assets/apple32.png
-WALL = public/assets/wall32.png
-
-SNAKE = public/assets/snake.json
-LEVEL_LIST = public/assets/levelList.json
-CONFIG = public/assets/config.json
-
 CSS = public/css/snek.css
-
 JS = public/js/snek.js
 
-OUTPUT = $(ICON) $(APPLE) $(WALL) $(SNAKE) $(LEVEL_LIST) $(CONFIG) $(CSS) $(JS)
+OUTPUT = $(IMAGES) $(TILESETS) $(JSON) $(ICON) $(CSS) $(JS)
 
-all: icon apple wall snake levelList config css js
+all: images tilesets json icon css js
+
+images: $(IMAGES)
+tilesets: $(TILESETS)
+json: $(JSON)
 icon: $(ICON)
-apple: $(APPLE)
-wall: $(WALL)
-
-snake: $(SNAKE)
-levelList: $(LEVEL_LIST)
-config: $(CONFIG)
-
 css: $(CSS)
-
 js: $(JS)
 
 public/favicon.ico: assets/icon.jpg
@@ -40,6 +31,9 @@ public/assets/%32.png: assets/%.jpg
 public/assets/%256.png: assets/%.jpg
 	convert $^ -resize 256x $@
 
+public/assets/%-ts.png: assets/%.png
+	convert $^ -scale 32x $@
+
 public/assets/%.json: assets/%.json
 	cp $^ $@
 

levels/level4.json

@@ -0,0 +1,39 @@
+{
+	"world": [
+		"               o               ",
+		"               o               ",
+		"    ooooo      o      ooooo    ",
+		"               f               ",
+		"  o                         o  ",
+		"  o      ooooooooooooo      o  ",
+		"  o                         o  ",
+		"  o            f            o  ",
+		"  o            o            o  ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"     o                   o     ",
+		"ooof o foooooo   oooooof o fooo",
+		"     o                   o     ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"     o         o         o     ",
+		"  o            o            o  ",
+		"  o            f            o  ",
+		"  o                         o  ",
+		"  o      ooooooooooooo      o  ",
+		"  o                         o  ",
+		"               f               ",
+		"    ooooo      o      ooooo    ",
+		"               o               ",
+		"               o               "
+	],
+	"delay": 100,
+	"snake": [
+		[16, 4]
+	]
+}

src/js/assets.js

@@ -3,18 +3,23 @@ const ProgressBar=require('progress');
 const assetSpecs=[
 	{ name: 'fruit',     filename: 'apple32.png',    type: 'image' },
 	{ name: 'wall',      filename: 'wall32.png',     type: 'image' },
+	{ name: 'hole',      filename: 'hole-ts.png',     type: 'image' },
 	{ name: 'snake',     filename: 'snake.json',     type: 'json'  },
 	{ name: 'levelList', filename: 'levelList.json', type: 'json'  },
 	{ name: 'config',    filename: 'config.json',    type: 'json'  }
 ];
 
+const tasks=[
+	{ from: 'hole', type: 'tileset', tiles: ['base', 'ul', 'dr', 'dl', 'ur', 'l', 'r', 'd', 'u'], steps: 9 }
+];
+
 const cvs=document.createElement('canvas');
 cvs.width=400;
 cvs.height=50;
 cvs.classList.add('progressBar');
 cvs.classList.add('hiddenBottom');
 
-const bar=new ProgressBar(assetSpecs.length*2);
+const bar=new ProgressBar(assetSpecs.length*2+tasks.reduce((a, t) => a+t.steps, 0));
 bar.addUpdateListener(() => bar.draw(cvs));
 bar.draw(cvs);
 
@@ -27,11 +32,11 @@ bar.addReadyListener(() => {
 });
 
 //XXX purposefully slow down asset loading
-const sleep=(ms) => new Promise(ok => setTimeout(ok, ms));
+const sleep=(ms=1000) => new Promise(ok => setTimeout(ok, ms*Math.random()));
 
 const loadAsset=async (asset) => {
 	const response=await fetch('assets/'+asset.filename);
-	await sleep(1000*Math.random());
+	await sleep();
 	bar.update();
 	let result;
 	switch(asset.type) {
@@ -43,7 +48,7 @@ const loadAsset=async (asset) => {
 			result=await createImageBitmap(await response.blob());
 			break;
 	}
-	await sleep(1000*Math.random());
+	await sleep();
 	bar.update();
 	return [asset.name, result];
 };
@@ -52,18 +57,37 @@ let assets=Object.create(null);
 let ready=false;
 let readyListeners=[];
 
-Promise
-	.all(
-		assetSpecs.map(a => loadAsset(a))
-	).then(arr => {
-		arr.forEach(([name, value]) => {
-			assets[name]=value;
-		});
-		ready=true;
-		readyListeners.forEach(fn => fn.bind(fn)());
-		readyListeners=null;
+(async () => {
+	let arr=await Promise
+		.all(
+			assetSpecs.map(a => loadAsset(a))
+		);
+
+	arr.forEach(([name, value]) => {
+		assets[name]=value;
 	});
 
+	for(let task of tasks) {
+		const source=assets[task.from];
+		switch(task.type) {
+			case 'tileset': {
+				let asset=assets[task.from]=Object.create(null);
+				for(let tId in task.tiles) {
+					const tName=task.tiles[tId];
+					asset[tName]=await createImageBitmap(source, 0, source.width*tId, source.width, source.width);
+					await sleep(100);
+					bar.update();
+				}
+				break;
+			}
+		}
+	}
+
+	ready=true;
+	readyListeners.forEach(fn => fn.bind(fn)());
+	readyListeners=null;
+})();
+
 const onReady=(fn) => {
 	if(ready) fn.bind(fn)();
 	else readyListeners.push(fn);

src/js/snek.js

@@ -1,6 +1,4 @@
-const [EMPTY, FOOD, WALL, SNAKE]=Array(4).keys();
-
-const ifNaN=(v, r) => isNaN(v)?r:v;
+const [EMPTY, FOOD, WALL, HOLE, HOLE_S, SNAKE]=Array(6).keys();
 
 class SnekGame {
 	constructor(settings, canvas, rules) {
@@ -20,11 +18,12 @@ class SnekGame {
 							case ' ': return EMPTY;
 							case 'f': return FOOD;
 							case 'w': return WALL;
+							case 'o': return HOLE;
 						}
 					})();
 				}
 			}
-			//
+
 			// extract the dimensions
 			this.dimensions=[this.world.length, this.world[0].length];
 
@@ -51,6 +50,9 @@ class SnekGame {
 			// add the walls
 			if(settings.walls) settings.walls.forEach(([x, y]) => this.world[x][y]=WALL);
 
+			// add the holes
+			if(settings.holes) settings.holes.forEach(([x, y]) => this.world[x][y]=HOLE);
+
 			// add the food
 			settings.food.forEach(([x, y]) => this.world[x][y]=FOOD);
 			this.fruits=[...settings.food];
@@ -62,9 +64,13 @@ class SnekGame {
 
 		// get the head and initial direction
 		this.head=[...settings.snake[0]];
-		this.direction=[
-			ifNaN(settings.snake[0][0]-settings.snake[1][0], 1),
-			ifNaN(settings.snake[0][1]-settings.snake[1][1], 0)
+		if(settings.snake.length>=2) this.direction=[
+			settings.snake[0][0]-settings.snake[1][0],
+			settings.snake[0][1]-settings.snake[1][1]
+		];
+		else this.direction=[
+			1,
+			0
 		];
 		this.lastDirection=this.direction
 
@@ -115,18 +121,46 @@ class SnekGame {
 
 		// draw our walls
 		const wall=assets.get('wall');
+		const hole=assets.get('hole');
+
+		const putTile=(x, y, tile) => this.ctx.drawImage(
+			tile,
+			offsetX+cellSize*x,
+			offsetY+cellSize*y,
+			cellSize,
+			cellSize
+		);
+		const checkAdj=(x, y) => {
+			let adj={};
+			adj.u=this.world[x][y-1];
+			adj.d=this.world[x][y+1];
+			adj.l=(this.world[x-1] || [])[y];
+			adj.r=(this.world[x+1] || [])[y];
+			adj.ul=(this.world[x-1] || [])[y-1];
+			adj.ur=(this.world[x+1] || [])[y-1];
+			adj.dl=(this.world[x-1] || [])[y+1];
+			adj.dr=(this.world[x+1] || [])[y+1];
+			return adj;
+		};
 		for(let x=0; x<this.dimensions[0]; x++) {
 			for(let y=0; y<this.dimensions[1]; y++) {
 				switch(this.world[x][y]) {
 					case WALL:
-						this.ctx.drawImage(
-							wall,
-							offsetX+cellSize*x,
-							offsetY+cellSize*y,
-							cellSize,
-							cellSize
-						);
+						putTile(x, y, wall);
 						break;
+
+					case HOLE: 
+					case HOLE_S: {
+						putTile(x, y, hole.base);
+						let adj=checkAdj(x, y);
+						Object
+							.keys(adj)
+							.filter(k => adj[k]==HOLE || adj[k]==HOLE_S)
+							.forEach(k => putTile(x, y, hole[k]));
+						break;
+						// technically, this works for all shapes
+						// however, the tileset only handles convex shapes
+					}
 				}
 			}
 		}
@@ -198,7 +232,13 @@ class SnekGame {
 
 		// get our tail out of the way
 		const tail=this.snake.pop();
-		this.world[tail[0]][tail[1]]=EMPTY;
+		switch(this.world[tail[0]][tail[1]]) {
+			case HOLE_S:
+				this.world[tail[0]][tail[1]]=HOLE;
+				break;
+			default:
+				this.world[tail[0]][tail[1]]=EMPTY;
+		}
 
 		// check for out of world conditions
 		if(head[0]<0 || head[0]>=this.dimensions[0] || head[1]<0 || head[1]>=this.dimensions[1]) {
@@ -214,8 +254,21 @@ class SnekGame {
 			// you hit, you die
 			case WALL:
 			case SNAKE:
+			case HOLE_S:
 				return this.die();
 
+			// if either 3 consecutive segments or the whole snake is on a hole, you die
+			case HOLE:
+				if(
+					this.snake.length==0 ||
+					this.snake.length==1 &&
+						this.world[this.snake[0][0]][this.snake[0][1]]==HOLE_S ||
+					this.snake.length>=2 &&
+						this.world[this.snake[0][0]][this.snake[0][1]]==HOLE_S &&
+						this.world[this.snake[1][0]][this.snake[1][1]]==HOLE_S
+				) return this.die();
+				break;
+
 			// you eat, you don't die
 			case FOOD:
 				// re-grow the snake
@@ -251,7 +304,13 @@ class SnekGame {
 		}
 
 		// move our head forward
-		this.world[head[0]][head[1]]=SNAKE;
+		switch(this.world[head[0]][head[1]]) {
+			case HOLE:
+				this.world[head[0]][head[1]]=HOLE_S;
+				break;
+			default:
+				this.world[head[0]][head[1]]=SNAKE;
+		}
 		this.snake.unshift(head);
 
 		// automatic speed increase
@@ -301,6 +360,7 @@ class SnekGame {
 	}
 
 	handleInputs(inputs) {
+		// change direction if the input is valid
 		const trySet=(dir) => {
 			if(!dir.every((e, i) => e==this.lastDirection[i] || e==-this.lastDirection[i])) {
 				this.direction=dir;
@@ -308,6 +368,7 @@ class SnekGame {
 			}
 		}
 
+		// reduce buffer duration
 		Object
 			.keys(inputs)
 			.forEach(k => {
@@ -318,11 +379,13 @@ class SnekGame {
 				else inputs[k]=v;
 			});
 
+		// try all inputs in order and unbuffer them if valid
 		if(inputs.left && trySet([-1, 0])) return delete inputs.left;
 		else if(inputs.right && trySet([ 1, 0])) return delete inputs.right;
 		else if(inputs.up && trySet([ 0,-1])) return delete inputs.up;
 		else if(inputs.down &&  trySet([ 0, 1])) return delete inputs.down;
 
+		// buffering might be disabled
 		if(inputs.clearBuffer) {
 			Object
 				.keys(inputs)