Add random food & walls

levels/2.json

@@ -4,6 +4,7 @@
     "walls": [
         [5,5], [5,6], [5,7], [5,8], [40, 35], [38, 35], [23, 35]
     ],
+    "randWallFreq": 5000,
     "food": [
         [10,10],
         [11,10],
@@ -13,6 +14,7 @@
         [20, 23],
         [20, 21]
     ],
+    "randFoodFreq": 2000,
     "snake": [
         [4,2], [4,1], [3,1], [2,1]
     ],

script.js

@@ -41,6 +41,16 @@ function drawLine(ctx, x1, y1, x2, y2) {
     ctx.stroke();
 }
 
+/**
+ * Generate a random number
+ * 
+ * @param {Number} min Minimum value
+ * @param {Number} max Maximum value
+ */
+function randInt(min, max) {
+    return Math.floor((Math.random()*max) + min)
+}
+
 // Get elements
 const startScreen = byId("startScreen")
 const gameScreen = byId("gameScreen")
@@ -267,6 +277,32 @@ async function startGame(gameID) {
         if(["ArrowDown", "ArrowLeft", "ArrowRight", "ArrowUp"].includes(ev.key))
             key = ev.key;
     });
+
+    // Automatically generate new map element if required
+    if(level.randWallFreq) {
+        const int = setInterval(() => {
+            if(!canvas.isConnected)
+                clearInterval(int);
+            else {
+                const pos = [randInt(0, map.length), randInt(0, map[0].length)]
+                if(map[pos[0]][pos[1]] == EMPTY)
+                    map[pos[0]][pos[1]] = WALL;
+            }
+        }, level.randWallFreq);
+    }
+
+    // Automatically generate new map element if required
+    if(level.randFoodFreq) {
+        const int = setInterval(() => {
+            if(!canvas.isConnected)
+                clearInterval(int);
+            else {
+                const pos = [randInt(0, map.length), randInt(0, map[0].length)]
+                if(map[pos[0]][pos[1]] == EMPTY)
+                    map[pos[0]][pos[1]] = FOOD;
+            }
+        }, level.randFoodFreq);
+    }
 }
 
 /**