Added collectables

Makefile

@@ -7,6 +7,7 @@ www/js/escalator.js: $(shell find src -name "*.js")
 		src/utils.js \
 		src/screen.js \
 		src/gui.js \
+		src/collectable.js \
 		src/scene.js \
 		src/box.js \
 		src/platform.js \

src/collectable.js

@@ -0,0 +1,11 @@
+class Collectable {
+    constructor(x, y) {
+        this.size = 0.1;
+        this.x = x;
+        this.y = y;
+        this.collected = false;
+    }
+}
+
+Collectable.texture = new Image();
+Collectable.texture.src = "img/collectable.png";

src/scene.js

@@ -9,6 +9,10 @@ class Scene extends Screen {
             this.maxHeight = 0;
         }
 
+        if (this.collectableNumber === undefined) {
+            this.collectableNumber = 0;
+        }
+
         this.initialize();
 
         this.addEventListener('touchstart', (event) => {
@@ -24,11 +28,24 @@ class Scene extends Screen {
         window.localStorage.setItem("maxHeight", value);
     }
 
+    get collectableNumber() {
+        return window.localStorage.getItem("collectableNumber");
+    }
+
+    set collectableNumber(value) {
+        window.localStorage.setItem("collectableNumber", value);
+    }
+
+    getCollectable(i) {
+        this.collectableNumber = parseInt(this.collectableNumber, 10) + i;
+    }
+
     initialize() {
         super.initialize();
 
         this.player.reset();
         this.platforms = [];
+        this.collectables = [];
         this.cameraHeight = 0;
         this.cameraSpeed = 0;
         this.currentHeight = 0;
@@ -39,10 +56,10 @@ class Scene extends Screen {
         this.currentMaxHeight = this.maxHeight;
 
         // Generate random initial platforms
-        for (let i = 0.25; i <= 2; i += 0.33) {
-            let platform = new Platform(Math.random(), i, 0.2);
-            this.addPlatform(platform);
-        }
+        // for (let i = 0.25; i <= 2; i += 0.33) {
+        //     let platform = new Platform(Math.random(), i, 0.2);
+        //     this.addPlatform(platform);
+        // }
 
     }
 
@@ -81,14 +98,32 @@ class Scene extends Screen {
             this.status = Status.GameOver;
         }
 
-        // The last platform is the highest.
-        let last = this.platforms[this.platforms.length - 1];
+        while(true) {
 
-        // If the last platform is on screen, we need to create the next platform.
-        if (last.y <= this.cameraHeight + 1) {
-            let diff = 0.1 + Math.random() * 0.4;
-            let platform = new Platform(Math.random(), last.y + diff, 0.2);
-            this.platforms.push(platform);
+            // The last platform is the highest.
+            let last = this.platforms[this.platforms.length - 1];
+
+            // If the last platform is on screen, we need to create the next platform.
+            if (last === undefined || last.y <= this.cameraHeight + 1) {
+
+                let lastY = last === undefined ? 0 : last.y;
+
+                let diff = 0.1 + Math.random() * 0.4;
+                let platform = new Platform(Math.random(), lastY + diff, 0.2);
+                this.platforms.push(platform);
+
+                if (last !== undefined && Math.random() < 0.2) {
+
+                    // Create a random coin
+                    let x = Math.random();
+                    let y = lastY + Math.random();
+
+                    this.collectables.push(new Collectable(x, y));
+                }
+
+            } else {
+                break;
+            }
         }
 
         // Increase position of the camera
@@ -135,6 +170,26 @@ class Scene extends Screen {
             }
         }
 
+        // Detect collision with collectable
+        for (let collectable of this.collectables) {
+
+            if (collectable.collected) {
+                continue;
+            }
+
+            // Ugly but don't care
+            // Copied and adapted from sdz
+            if(    (collectable.x >= next.x + next.size / 2)
+                || (collectable.x + collectable.size <= next.x)
+                || (collectable.y >= next.y + next.size)
+                || (collectable.y + collectable.size <= next.y)) {
+
+            } else {
+                collectable.collected = true;
+                this.getCollectable(1);
+            }
+        }
+
         // Collision with the ground
         if (this.player.y <= 0) {
             this.player.collide(0);
@@ -162,6 +217,10 @@ class Scene extends Screen {
             this.drawPlatform(platform);
         }
 
+        for (let collectable of this.collectables) {
+            this.drawCollectable(collectable);
+        }
+
         this.drawObject(this.player);
 
         this.context.resetTransform();
@@ -173,6 +232,21 @@ class Scene extends Screen {
         }
     }
 
+    drawCollectable(object) {
+
+        if (!object.collected) {
+            let size = object.size * this.width();
+
+            this.context.drawImage(
+                Collectable.texture,
+                0, 0, 64, 64,
+                (object.x - object.size / 2) * this.width(),
+                (1 - object.y - object.size / 2) * this.height(),
+                size, size
+            );
+        }
+    }
+
     drawHighScoreLine() {
         if (this.currentMaxHeight <= 0) {
             return;
@@ -232,6 +306,14 @@ class Scene extends Screen {
         }
         this.context.fillText(text, 0, 20);
 
+
+        // Draw coin number
+        this.context.drawImage(Collectable.texture,
+            0, 0, 64, 64,
+            0, fontSize + 5, 0.05 * this.width(), 0.05 * this.width());
+
+        this.context.fillText(this.collectableNumber, 0.05 * this.width() + 5, 2 * fontSize)
+
         if (this.status === Status.Running) {
             // Draw pause button
             let box = this.makePauseBox();