AI of a robot is programmed as a script in the Angel Script Language. A script fully describes the behavior of a robot and is evoked at each cycle of the game for each robot of a team. All the robots of the same team share the same script. Angel Script Language syntax is very close to the syntax of C++.

Main function of a script is the function Execute. This function is called from a game simulator. Function prototype:

void Execute(RobotState&, const Environment&);

Function arguments are described below.

Environment class

An Environment object specifies parameters of a game world.

class Environment
{
public:
    int bases_count;
    int field_width; 
    int field_height; 
    int robot_hp; 
    int base_hp; 
    int shoot_range;
    int view_range; 
    int transmit_range; 
    int reload_time;
    int robot_construction_time;
    int msg_size;
    int memory_size; 
    int iter;
    int last_iter;
    int timeout;

    int dist(int x1, int y1, int x2, int y2);
    bool shift(int x, int y, int dir, int &dx, int &dy);
    int get_dir(int x1, int y1, int x2, int y2);
};

Class members:

This attributes are set before the first cycle of a game, are common for all robots and bases and cannot be changed during the game.

Member functions:

RobotState class

The RobotState object defines the state of a robot. So, the state of the robot is preserved in such an object between the cycles and passed each cycle to the Execute function to be processed.

class RobotState
{
public: 
    int x, y;
    int team;
    int hitpoints;
    int cooldown; 

    bool shoot;
    bool transmit;
    int move_direction;
    int shoot_x, shoot_y;

    uint get_msgs_num();
    uint get_robots_num();
    uint get_bases_num();      

    Unit get_robot(uint ind);
    Unit get_base(uint ind);

    void set_mem_int(uint pos, int val);
    void set_msg_int(uint pos, int val);

    int get_mem_int(uint pos);
    int get_msg_int(uint pos);
    int get_msgs_int(uint ind, uint pos);

    void copy_to_msg(uint ind); 
};

First group of members describes characteristics of the robot that cannot be changed by the robot (that is by Execute function):

Second group describes robot’s decisions to act at the current cycle. These values are computed by the Execute function.

Member-functions of the RobotState class return different information on the units (robots or bases) in the view range of the robot:

Unit class

Unit class is used to represent information about visible units:

class Unit
{
public:
    int x, y;
    int team;
    int dist;
};

Unit class members:

Member-functions of the class RobotState to handle memory and messages:

All the incoming messages are received before the call to the Execute function. If the robot wished to broadcast a message, it has to put on the broadcasting flag and prepare the “main” message. Memory state can be used to keep information between the cycles.

Additional functions

• rand() – generates random integer number
• print(const string& str) – prints str to a screen
• print(int n) – prints integer value of n to a screen