For the first assignment, you used the "rcssclient" to allow you to communicate with the simulator by hand. You will now alter a similar client to perform some tasks automatically. In this assignment, you will implement some simple soccer-playing agents. All parts of this assignment can be done with purely reactive behaviors. Please describein your email to us the extent to which your behaviors are reactive. (It's OK if they're not, just make sure that if you create an agent that is non-reactive in some way, you describe clearly why not in your email).

This assignment (and all for this course) is about creating agents. It's not about programming. If you have programming questions/problems, etc. (e.g. "How do I generate a random number in C?") ask the class list early and often.

A good debugging tool is to print stuff out, in C you can do it with printf. Here is a simple example which should help (for more info check the printf reference):

  #include <stdio.h> // This should be at the top of the file
  ...
  char str[10] = "agents"; 
  int num = 1;
  double dbl = 2.0;
  // It prints out the value of variables str,num and dbl. 
  // Notice the difference between %s, %d and %f.
  printf("string: %s, int:%d, double:%f\n", str, num, dbl); 

A good method for parsing strings, is sscanf. Here is an example:

  #include <stdio.h> // This should be at the top of the file
  ...
  char str[20] = "((b) 23 1.5)"; 
  int i = 0;
  double dbl = 0;
  // The integer value appeared at the place of the %d would go to the i variable, 
  // and the the double value would go to the dbl variable.
  sscanf(str, "((b) %d %lf)", &i, &dbl); 
  printf("i:%d dbl:%f\n", i, dbl); 

The strstr() function may also be useful. (Here is code that parses a sample server message and find the distance and angle to the right goal.)

Also, the sprintf() function is useful for creating strings with variable content. For example, you can use sprintf() to create a

(dash N)

C/C++ Reference

Score a goal

Instructions:

1. Copy over the files in the sampleclient directory to any directory in your account:

     % cp -r /projects/cs344M.pstone/sampleclient/ .
   

2. Go into your version of the sampleclient and compile by typing "make".
3. In a new terminal window, start the soccer server (as you did in the previous assignment).

     % rcsoccersim
   

4. Back in the other window, run the client:

    
     % ./client
   

You will see the same behavior as last week. The agent is waiting for you to type a command; if you send the init command "(init (version 9.3))", the agent will display all of the percepts that it receives to the screen.

Looking into the code (client.c), you will see that it uses select() to read from multiple input streams: one for receiving input from the server, and one for receiving input from the shell.

Your task is to alter the code so that the player does the following without any input from the shell:

• Connect to the server with version 11 protocol.
• Immediately after connecting, it should move to a random place on its side of the field "(move x y)" where -52.5 < x < 0, -34 < y < 34.
• It should find the ball, go the the ball, find the opponent's goal, "(g r)" for the left team or "(g l)" for the right team, and kick the ball towards that goal. The player should decide what to do based only on its latest sight. It should send at most one command after every sight it receives.

• The player should send "(init <teamname> (version 11))" as the first thing that it does. This message is important, because the simulator won't send you anything until you send it an "init" message.
• The response from the server to the "(init)" command tells which side the player is on: (init [l/r]...) where "l" means left side, "r" means right side.
• Search for the statement that starts printf( "recv". Rather than printing out the sensation, parse it to find the distance and angle to the ball and/or the relevant goal (if they're in the player's view).
• The format of visual information of sensation is:

  (see Time Object*)
  

  where "Time" is the current simulator timestep (it will only increase after you've told it to kick off) and "Object*" means that there will be zero or more "Object"s. Each Object has one of the following forms:

  (ObjName Distance Direction DistChng DirChng BodyDir HeadDir)
  (ObjName Distance Direction DistChng DirChng)
  (ObjName Distance Direction)
  (ObjName Direction)
  

  The ObjName variable can be many things, including:
  (b) for the ball
  (g r) for right goal
  (g l) for left goal
  (p "teamname" "uniform number") for players

  For more information on the format of the sensation, look at page 24 (the manual page, not the PDF page number) of the manual. Note that sometimes if objects are close but outside of the viewcone, they can still be "seen" in a rough manner (page 30 of the manual).

• Decide on a single action (kick/dash/turn) with appropriate parameters and send them to the server using the "send" (or "send_message") command as is done in the current routine that accepts keyboard input.
• Beware of altering the socket protocol in the client. The protocol implemented by the sampleclient is as follows: the init message is sent to the server on port 6000. The server replies on a different port, and all subsequent messages are to be sent to that port.
• By default, a player is not allowed to kick the ball twice in a row on a kick_off. You can get around this by starting the game with a drop ball (right-click in the simulator window). Or, you can turn off this rule in the simulator for this part of the assignment. You can do it by two ways:
  
  Way 1: Changing the ~/.rcssserver/server.conf file. (not the ~/.rcssserver-server.conf)
  
  For example if you want to turn off the free kick faults , then change the following parameter: server::free_kick_faults = false
  
  Way 2: If you are thinking of sending command line params, follow the following steps.
  
  1. Copy the rsscoccersim script file to one of your local folder
  
  2. Change your PATH so that the file from your local directory comes before $RCSSBASE/bin/ (the reason behind doing this is the /projects/cs344M.pstone/rcss_11/bin/rsscoccersim is readonly and hence any change should be made from the local copy)
  
  3. And then copy the following lines:
  
  server_string="server"
  
  server_opts="$server_string::free_kick_faults=false"
  
  $SERV $server_opts &
  
  before the $SERV line
  
  4. Remove the $SERV line
  

What to turn in:

1 on 1

What to turn in:

A logfile called [yourlogin]-1on1.log

Passing

Hints:

use_offside: on

use_offside: off

Grading

This assignment will be graded as follows:

Part 1:

• 4 points if it works smoothly.
• 3.5 points if it doesn't work so well but still scores

Part 2: 1 point if it works.

Part 3:

• 4 points if it works smoothly. (it's OK if the ball doesn't go straight to the teammate, as long as the teammate can go retrieve the ball and keep playing)
• 3.5 points if a couple of passes are completed, but it doesn't seem like it could keep working (players get bunched up, etc.)
• 3 points if 1 pass is completed.

Description:

• 1 point if you indicate an understanding of "reactive"
• .5 if you provide a poor description
• 0 if you don't provide a description