Starfied 2

Background and Overview

A tribute to the game Volfied from 1989.

The Story: A space pilot won the space battle from the alien attack on his home plant Volfied. Now he is going to a galaxy far far away to protect other inhabitants home planets from the same alien attackers.

A player controls a marker that can move around the edges of the rectangle. The objective is to claim at least 80% of a level's area to finish the level.

Player can move using the keyboard arrows . Play the Game

Technologies

• Vanilla JavaScript for overall structure, game logic and DOM manipulation
• Scss for stylesheets
• Webpack to bundle and serve up the various scripts

Features

• Move with the keyboard: left, right, up, down.
• Hear Music while playing and mute music.
• View his score and level.
• Enemies
• The page has the rules of the game

Collision detection

For implementing the collision the function collision checks the move position in the player and enemy class and change the state of the board class if found collision.

//Player Class and Enemy Class
collision (){
  this.board.collision();
}

//board class
collision (){
  this.collisions = true;
}

Flood fill Algorithm

When the player claims an area the area changes color to the color of the boarder and becomes a safe area for the player. To implement the change on a specific area, the function checks for connection to the start position through values in the grid and if a connection exist the color of the position changes.

flood (coords){
  let coordsVal = this.getCellAt(coords);
  if (coordsVal === "1") return;

  this.setCellAt(coords, "1");
  this.points += 1;

  let diff = [[0,1], [0,-1], [-1,0], [1,0]];
  diff.forEach( options => {
    let newCoords = [coords[0] + options[0], coords[1] + options[1]];
    this.flood(newCoords);
  });
  return;
}

Enemy movement

The movement of the enemy is determined by a random selection from an array of possible movements. if the selected position is on the game outline the move position will change.

moves (randomDiff){
  let diff;
  let moveTo;
  try {
    moveTo = [this.position[0] + randomDiff[0], this.position[1] + randomDiff[1]];
  }
  catch(err) {
    moveTo = this.position;
  }

  let moveVal = this.board.getCellAt(moveTo);
  while(moveVal === "1" || !this.board.validMove(moveTo)) {
    try {
      diff = this.random_move();
      moveTo = [this.position[0] + diff[0], this.position[1] + diff[1]];
    }
    catch(err) {
      moveTo = this.position;
    }
    moveVal = this.board.getCellAt(moveTo);
  }

Bonus features

• Item to improve abilities, ex shooting
• Add more levels.
• Add shooting for enemies and player.
• Improve graphics and add different sound in each level.