rdzanym/matacka

A game with local multiplayer and quite strong computer players.

Matacka 🐍

Description

It is a game for 2-12 players, including at least one human player (others can be computer-contolled). Game area is a rectangular bitmap. Players are moving around the game area with different-coloured "snakes". A snake dies after going into the wall or hitting a snake.

Scoring system

After death of a player every still living player is awarded points. After nth collision every living player gets n points. When only one player is left, a new round begins. The game goal is to collect a maximum number of points (equal to p*(p+1), where p is the number of players), and then win a round. When any of the players achieves the goal, the game ends.

Movement

All snakes are moving at the same speed. The angular speed is constant throughout the whole game. The linear speed is lower in the beginning each round (resulting in a smaller turn radius) so that the players have a greater chance to survive an unfortunate spawn. The linear speed starts at 30% of the base value and gradually rises to 100% in the first 90 frames (1.5 seconds). After that time, when both angular and linear speed aren't changing anymore, the snakes have a constant turning radius, which means that during the turn they move along a circumference of a circle with a certain radius.Each player has a position (x,y coordinates) on the map and the angle of current movement. These values are updated each frame.

  Player p = players.get(i);
  double px = p.getX() + speed * Math.cos(p.angle);
  double py = p.getY() + speed * Math.sin(p.angle);
  if (p.direction.equals(Player.Direction.Right))
      p.angle += angularSpeed;
  else if (p.direction.equals(Player.Direction.Left))
      p.angle -= angularSpeed;

  p.setPosition(px, py);

Controls

In each frame a player can make one of 3 moves: turn right/left or go straight. In the beginning of the game each human player is assigned two buttons responsible for the snake turns. The computer-controlled players use the same interface, but set their Direction variable without using buttons.

GUI

In the beginning of the game the user can choose the total number of players and the number of human players. During the game a scoreboard is displayed, allowing players to track their progress.

AI algorithm

The algorithm tries to find the longest path with no collision. It works asynchronously for each player, modifying the variable representing the first move decision in a found sequence. It is restarted with new parameters after every frame. Algorithm assumes that other players will go straight, right and left at the same time. Because each computer-controlled player is assigned a new thread, there may be a performance drop (due to starvation) when the number of computer-controlled players is greater or equal to the number of available CPU threads (one thread is used for the main application).