1. Alien Wars Simulation (AWS) (Analysis Model) COP 4232: Software Systems Development © Dr. David A. Workman School of CS University of Central Florida July 18, 2004 Revised November 1, 2004 July 18, 2005

2. Clash of the Aliens (c) Dr. Workman2 Clash with the Aliens (Description) World View (PROBLEM DESCRIPTION) It is the year 2100 and the myth about aliens has finally been dispelled – they have invaded Earth!! They are among us! However, all is not lost. While the Aliens appear to be superior to Humans in many ways, and although they are hostile toward us, they have been successfully captured - alive. Experiments conducted with captured specimens have found they are vulnerable to high-energy anti-matter lasers (AML) just recently developed. Your firm, Galaxy Security Inc.(GSI), has been contracted by the Government to hunt down and exterminate these intruders. GSI has perfected the AML technology and has produced a portable weapon to be used as standard equipment for all agents assigned to conduct the mission to search out and destroy the “aliens among us.” That is the good news. Aliens possess weapons much more deadly than GSI’s AML gun – that is, their range is twice that of the AML gun and is just as lethal. The good news is that the re- charge time on Alien weapons is three times longer than the re-charge time for AML guns. More bad news: Aliens are much bigger and stronger than Humans and so hand-to-hand combat is definitely out! More good news: they are 50% slower than Humans in ground speed. Before GSI embarks on this very dangerous mission, they have decided to develop a battle simulation to evaluate various tactical strategies for engaging the Aliens to reduce the risk to Humans and maximize our chances of survival. This is where you come in – GSI has hired your team to develop this simulator. Dr. Workman is GSI’s primary POC and SME and will be working closely with you on requirements for the simulator and will provide test data.

3. July 18, 2005Clash of the Aliens (c) Dr. Workman3 Clash with the Aliens (World View) World View (continued) Battle Field GSI Agent Alien GSI Agent Alien Obstacle

4. July 18, 2005Clash of the Aliens (c) Dr. Workman4 Clash with the Aliens (Agents) Battlefield: The Virtual World object. –Parameters: #Humans, #Aliens, #Obstacles –Constituients: {Obstacle}, {Humans}, {Aliens}, Ground Ground (Truth): The actual field of play. It has the responsibility of maintaining the current position and velocity of all Agents and Obstacles on the battlefield; Obstacles do not move, but Agents do. It updates this information every clock tick by sending itself a message. Any object that changes its velocity must notify Ground. Conversely, Ground responds to requests for information about what objects are visible within a specified field of view. See below. A sweep sector is defined by: Range Vector (r) gives radius and direction of Sweep Sweep Angle (α) An agent requests the identity of all objects within the specified sector. Ground returns a list of visible object descriptors. The descriptors contain the object’s handle, its position, velocity, and orientation vectors (if defined). In the example illustrated, objects “3”, “2”, and “4” would be visible, but “1”, “5” and “6” would not be visible. 3 4 5 6 1 2 α r

5. July 18, 2005Clash of the Aliens (c) Dr. Workman5 Clash with the Aliens (Agents) Humans: This is an Agent subclass defining the “Blue” force (the good guys). –Parameters: Initial position, Initial velocity, other(see Specs) –Behavior: Humans are seaching out Aliens to destroy. Using self messages to control frequency of search, each Human asks Ground for visible objects by sending a Sweep message. Based on the visible objects and their orientation, the Human plans a strategy for attack or retreat. In attack mode, the Human fires at an Alien. In retreat state, the Human is heading for cover. Humans must be prepared for a Kill message (from an Alien) in any state. Humans must be prepared for a Collision message from Ground notifying the Human of approaching Obstacles, Aliens, and other Humans. Aliens: This is an Agent subclass defining the “Red” force (the bad guys). –Parameters: Initial position, Initial velocity, other (see Specs) –Behavior: (similar to that of Humans)

6. July 18, 2005Clash of the Aliens (c) Dr. Workman6 Clash with the Aliens (Passive Classes) Obstacles: Circular, stationary objects of varying radii. –Parameters: Radius, Initial Position Radar Sweep: Defines area of battle field swept by radar. Serves as the basis for communicating with Ground. –Parameters: Origin vector, Range vector, Sweep angle (radians). Radar Blip: Defines characteristics of a visible object detected by a Radar Sweep. –Parameters: Object Range vector (relative to Sweep origin), Object Orientation vector (where is the object “looking” – applies only to Agents, not Obstacles), Object velocity vector (relative to object’s origin). Radar Echo: A list of Radar Blips return by Radar Sweep. Note: This need not be an exhaustive list Of Passive Classes!

7. July 18, 2005Clash of the Aliens (c) Dr. Workman7 Clash with the Aliens (Messages) Collisions: a collision message identifies an object with which the receiving agent is about to collide, if evasive action is not taken. Such messages are generated by Ground and sent, when necessary, to each agent. Ground should have a parameter(s) that determines the distance between objects that precipitates this type of message. Kills: If any agent receives such a message, it has been eliminated from the rest of play. It should record its kill position and its kill time for post simulation analysis. It should enter a “kill” state for post simulation analysis and terminate its behavior. Any future Events for which the killed agent is the receiver should be purged from the EventMgr. Note: it is necessary to add a purge() method to EventMgr identifying the Sendr handle to accomplish this. Note: This need not be an exhaustive list Of Passive Classes!