Semester Project Introduction

1. Introduction

• Semester project built around distributed simulation program Robowar
• Participants communicate with Robowar server through a client program
  • Client requests actions
  • Server reports game status
• Client can be very simple - mapping keystrokes to actions - or very complicated - completely automatic
• Your final semester project will be to write a client program for Robowar

2. The game

• Simple simulation of spaceships orbiting in gravity well
  • Gravity source is "the sun"
  • Ship obeys Newtonian physics (as opposed to Star Trek physics)
• Each player gets one spaceship
• Each spaceship can:
  • Turn left
  • Turn right
  • Fire thrusters
  • Fire torpedo
  • Enter "hyperspace"

3. Screen shot

4. Orbital maneuvering

• Spaceship can turn left or right incrementally
• Thrusters increase velocity along current axis
• Torpedos fire with current velocity plus increment along current axis
• Hyperspace instantaneously changes location and retains original velocity
• At i^th use, ship destroyed with probability i/10

5. Scoring

• Ship destroyed if:
  • Struck by torpedo
  • Flies into sun
  • Flies off edge of playing field
• Player scores 10 points for each opponents' ship destroyed
• Player scores -5 points each time own ship destroyed (ship can be "rebooted")

6. Architecture

• Server program
  • Typically runs on europa.eecs.lehigh.edu
  • Manages simulation
  • Accepts connections from clients
• Client program
  • Runs on desktop UNIX workstation
  • Accepts user input
  • Sends commands to server

7. Client-server protocol

• Uses TCP/IP
• Client sends commands to server:
  • Start/restart ship
  • Turn, fire, fire thrusters
  • Hyperspace
• Server sends status to client:
  • Location of spaceships and torpedos
  • Score
  • Spaceship termination event

8. Server location protocol

• Server listens for "ping" messages (UDP)
• Responds with own address
• Client locates with broadcast