Remote Control

Brutal Maze provides a INET (i.e. IPv4), STREAM (i.e. TCP) socket server which can be enabled in the config file or by adding the --server CLI flag. After binding to the given host and port, it will wait for a client to connect. Then, in each cycle of the loop, the server will send current details of each object (hero, walls, enemies and bullets), wait for the client to process the data and return instruction for the hero to follow. Since there is no EOT (End of Transfer) on a socket, messages sent and received between server and client must must be strictly formatted as explained below.

Server Output

First, the game will export its data to a byte sequence (which in this case, is simply a ASCII string without null-termination) of the length \(l\). Before sending the data to the client, the server would send the number \(l\) padded to 7 digits.

Below is the meta structure of the data:

<Map height (nh)> <Number of enemies (ne)> <Number of bullets (nb)> <Score>
<nh lines describing visible part of the maze>
<One line describing the hero>
<ne lines describing ne enemies>
<nb lines describing nb bullets>

The Maze

Visible parts of the maze with the width \(n_w\) and the height \(n_h\) are exported as a byte map of \(n_h\) lines and \(n_w\) columns. Any character other than 0 represents a blocking cell, i.e. a wall.

To avoid floating point number in later description of other objects, each cell has the width (and height) of 100, which means the top left corner of the top left cell has the coordinates of \((0, 0)\) and the bottom right vertex of the bottom right cell has the coordinates of \((100 n_w, 100 n_h)\).

The Hero

6 properties of the hero are exported in one line, separated by 1 space, in the following order:

Color:

The current HP of the hero, as shown in in the later section.

X-coordinate:

An integer within \([0, 100 n_w]\).

Y-coordinate:

An integer within \([0, 100 n_h]\). Note that the y-axis points up-side-down instead of pointing upward.

Angle:

The direction the hero is pointing to in degrees, cast to an integer from 0 to 360. Same note as above (the unit circle figure might help you understand this easier).

Can attack:

0 for no and 1 for yes.

Can heal:

0 for no and 1 for yes.

The Enemies

Each enemy exports these properties:

Color:

The type and the current HP of the enemy, as shown in the table below.

X-coordinate:

An integer within \([0, 100 n_w]\).

Y-coordinate:

An integer within \([0, 100 n_h]\).

Angle:

The direction the enemy is pointing to in degrees, cast to a nonnegative integer.

To shorten the data, each color (in the Tango palette) is encoded to a lowercase letter. Different shades of a same color indicating different HP of the characters.

HP	5	4	3	2	1
Butter
Orange
Chocolate
Chameleon
Sky Blue
Plum
Scarlet Red
Aluminium

Note

If a character shows up with color 0, it is safe to ignore it since it is a dead body yet to be cleaned up.

Flying bullets

Bullets also export 4 properties like enemies:

Color:

The type and potential damage of the bullet (from 0.0 to 1.0), encoded similarly to characters’, except that aluminium bullets only have 4 colors v, w, x and 0.

X-coordinate:

An integer within \([0, 100 n_w]\).

Y-coordinate:

An integer within \([0, 100 n_h]\).

Angle:

The bullet’s flying direction in degrees, cast to a nonnegative integer.

Example

Above snapshot of the game is exported as:

19 5 3 180
00000000000000000vvvv0000
v0000000000000000vvvv0000
v0000000000000000vvvv0000
v0000000000000000vvvv0000
vvvvvvvvvvvvvvvvvvvvv0000
vvvvvvvvvvvvvvvvvvvvv000v
vvvvvvvvvvvvvvvvvvvvv000v
vvvvvvvvvvvvvvvvvvvv00000
0000000000000000000000000
0000000000000000000000000
0000000000000000000000000
v000000000000000000000000
v000000000000000000000000
v000000000000000000000000
v000vvvvvvv000vvv0vvv0000
v000vvvvvvv000vvvvvvv0000
v000vvvvvvv000vvvvvvv0000
v000vvvvvvv000vvvvvvv0000
v000000vvvv000000vvvv0000
v 1267 975 47 0 1
p 1817 1050 45
g 1550 1217 45
a 2250 1194 45
p 2050 1017 45
e 1850 950 358
x 2126 1189 361
e 1541 1020 167
v 1356 1075 49

Client Output Format

Every loop, the server receives no more than 7 bytes in the format of <Movement> <Angle> <Attack>. Again, these values need to be specially encoded.

Movement

This is the most awkward one. As we can all imagine, there are nine different directions for the hero to move. Were they represented as two-dimensional vectors, at least three characters would be needed to describe such a simple thing, e.g. 1 0 for \(m = (1, 0)\), and in the worst-case scenario \(m = (-1, -1)\), we would need five: -1 -1. 40 bits are used to carry a four-bit piece of data, freaking insane, right? So instead, we decided to slightly encode it like this:

Direction	Left	Nil	Right
Up	0	1	2
Nil	3	4	5
Down	6	7	8

Angle

Direction to point to hero to, might be useful to aim or to perform a close-range attack manually. This value should also be converted to degrees and casted to a nonnegative integer.

Attack

Attack can be either of the three values:

0. Do nothing

1. Long-range attack

2. Close-range attack

Simple, huh? Though be aware that this won’t have any effect if the hero can yet strike an attack (as described in above section about The Hero).

Pseudo-Client

1. Create an INET, STREAMing socket sock

2. Connect sock to the address host:port which the server is bound to

3. Receive length \(l\) of data

4. If \(l > 0\), close sock and quit

5. Receive the data

6. Process the data

7. Send instruction for the hero to the server and go back to step 3

Your AI should try to not only reach the highest score possible, but also in the smallest amount of time. For convenience purpose, the server will log these values to stdout.

There are samples of client implementations in different languages in the client-examples directory (more are coming).