Add Asteroid game

CM2030 Graphics Programming/Topic 3/3.4.1/bulletSystem.js

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+class BulletSystem {
+  constructor() {
+    this.bullets = [];
+    this.velocity = new createVector(0, -5);
+    this.diam = 10;
+  }
+
+  run() {
+    this.move();
+    this.draw();
+    this.edges();
+  }
+
+  fire(x, y) {
+    this.bullets.push(createVector(x, y));
+  }
+
+  //draws all bullets
+  draw() {
+    fill(255);
+    for (var i = 0; i < this.bullets.length; i++) {
+      ellipse(this.bullets[i].x, this.bullets[i].y, this.diam, this.diam);
+    }
+  }
+
+  //updates the location of all bullets
+  move() {
+    for (var i = 0; i < this.bullets.length; i++) {
+      this.bullets[i].y += this.velocity.y;
+    }
+  }
+
+  removeBullet(index) {
+    if (this.bullets.length <= 0 || index < 0 || index >= this.bullets.length)
+      return;
+    this.bullets.splice(index, 1);
+  }
+
+  //check if bullets leave the screen and remove them from the array
+  edges() {
+    // YOUR CODE HERE (3 lines approx)
+    let leftBound = 0;
+    let rightBound = width;
+    let topBound = 0;
+    let botBound = height;
+
+    for (let i = 0; i < this.bullets.length; i++) {
+      let bullet = this.bullets[i];
+      if (
+        bullet.y + this.diam < topBound ||
+        bullet.y - this.diam > botBound ||
+        bullet.x - this.diam > rightBound ||
+        bullet.x + this.diam < leftBound
+      )
+        this.removeBullet(i);
+    }
+  }
+}