upgraded engine with input buffering and added arcade & survival

assets/levelList.json

@@ -20,6 +20,7 @@
 			"fruitRegrow": true,
 			"speedIncrease": true,
 			"speedMultiplier": 0.9,
+			"speedCap": 50,
 			"worldWrap": true
 		},
 		"levelFilename": "arcade-<l>.json",

assets/snake.json

@@ -3,5 +3,6 @@
 	"join": "round",
 	"cap": "round",
 	"headSize": 0.8,
-	"tailSize": 0.4
+	"tailSize": 0.4,
+	"tailWrapSize": 0.1
 }

levels/arcade-arcade.json

@@ -0,0 +1,12 @@
+{
+	"dimensions": [32, 32],
+	"delay": 200,
+	"food": [
+		[16, 16]
+	],
+	"snake": [
+		[16, 12],
+		[16, 11],
+		[16, 10]
+	]
+}

levels/arcade-survival.json

@@ -0,0 +1,16 @@
+{
+	"dimensions": [32, 32],
+	"delay": 200,
+	"food": [],
+	"snake": [
+		[16, 12],
+		[16, 11],
+		[16, 10]
+	],
+	"rules": {
+		"autoSpeedIncrease": true,
+		"autoSpeadIncreaseTicks": 10,
+		"autoSizeGrow": true,
+		"autoSizeGrowTicks": 100
+	}
+}

src/js/snek.js

@@ -1,5 +1,3 @@
-const assets=require('assets');
-
 const [EMPTY, FOOD, WALL, SNAKE]=Array(4).keys();
 
 const ifNaN=(v, r) => isNaN(v)?r:v;
@@ -51,7 +49,7 @@ class SnekGame {
 			}
 
 			// add the walls
-			settings.walls.forEach(([x, y]) => this.world[x][y]=WALL);
+			if(settings.walls) settings.walls.forEach(([x, y]) => this.world[x][y]=WALL);
 
 			// add the food
 			settings.food.forEach(([x, y]) => this.world[x][y]=FOOD);
@@ -68,6 +66,7 @@ class SnekGame {
 			ifNaN(settings.snake[0][0]-settings.snake[1][0], 1),
 			ifNaN(settings.snake[0][1]-settings.snake[1][1], 0)
 		];
+		this.lastDirection=this.direction
 
 		// store the snake
 		this.snake=[...settings.snake];
@@ -75,7 +74,6 @@ class SnekGame {
 		// get our canvas, like, if we want to actually draw
 		this.canvas=canvas;
 		this.ctx=canvas.getContext('2d');
-		//TODO this.gl=canvas.getContext('webgl');
 		
 		// load the custom rules
 		this.rules=Object.assign({
@@ -93,6 +91,8 @@ class SnekGame {
 	}
 
 	draw() {
+		const assets=require('assets');
+
 		// clear the canvas, because it's easier than having to deal with everything
 		this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
 
@@ -150,11 +150,22 @@ class SnekGame {
 		this.ctx.fill();
 
 		this.ctx.beginPath();
-		this.snake.forEach(([x, y], i) => {
+		this.snake.forEach(([x, y], i, a) => {
 			this.ctx.lineTo(
 				offsetX+cellSize*(x+1/2),
 				offsetY+cellSize*(y+1/2)
 			);
+			if(i!=0 && Math.hypot(x-a[i-1][0], y-a[i-1][1])>1) {
+				this.ctx.lineWidth=cellSize*snake.tailWrapSize;
+			} else {
+				this.ctx.lineWidth=cellSize*snake.tailSize;
+			}
+			this.ctx.stroke();
+			this.ctx.beginPath()
+			this.ctx.moveTo(
+				offsetX+cellSize*(x+1/2),
+				offsetY+cellSize*(y+1/2)
+			);
 		});
 		this.ctx.stroke();
 
@@ -174,6 +185,9 @@ class SnekGame {
 	}
 
 	step() {
+		this.tickId++;
+		this.lastDirection=this.direction;
+
 		// compute our new head
 		const head=[
 			this.snake[0][0]+this.direction[0],
@@ -227,12 +241,27 @@ class SnekGame {
 					this.fruits.push(cell);
 					this.world[cell[0]][cell[1]]=FOOD;
 				}
+
+				if(this.rules.speedIncrease) {
+					this.delay*=this.rules.speedMultiplier;
+					if(this.delay<this.rules.speedCap) this.delay=this.rules.speedCap;
+				}
 		}
 
 		// move our head forward
 		this.world[head[0]][head[1]]=SNAKE;
 		this.snake.unshift(head);
 
+		// automatic speed increase
+		if(this.rules.autoSpeedIncrease) {
+			if(this.delay>50 && this.tickId%this.rules.autoSpeadIncreaseTicks==0) this.delay--;
+		}
+
+		// automatic size grow
+		if(this.rules.autoSizeGrow) {
+			if(this.tickId%this.rules.autoSizeGrowTicks==0) this.snake.push(tail);
+		}
+
 		// victory condition
 		if(this.rules.winCondition=='fruit') {
 			if(!this.fruits.length) return this.win();
@@ -271,23 +300,20 @@ class SnekGame {
 
 	handleInputs(inputs) {
 		const trySet=(dir) => {
-			if(!(this.direction[0]==-dir[0] && this.direction[1]==-dir[1])) this.direction=dir;
+			if(!dir.every((e, i) => e==this.lastDirection[i] || e==-this.lastDirection[i])) {
+				this.direction=dir;
+				return true;
+			}
 		}
-		if(inputs.left) {
+		if(inputs.left && trySet([-1, 0])) return delete inputs.left;
-			trySet([-1, 0]);
+		else if(inputs.right && trySet([ 1, 0])) return delete inputs.right;
-		} else if(inputs.right) {
+		else if(inputs.up && trySet([ 0,-1])) return delete inputs.up;
-			trySet([ 1, 0]);
+		else if(inputs.down &&  trySet([ 0, 1])) return delete inputs.down;
-		} else if(inputs.up) {
-			trySet([ 0,-1]);
-		} else if(inputs.down) {
-			trySet([ 0, 1]);
-		}
-
-		Object.keys(inputs).forEach(k => delete inputs[k]);
 	}
 
 	start() {
 		this.firstStep=Date.now();
+		this.tickId=0;
 		this.playing=true;
 		requestAnimationFrame(() => this.tick());
 	}