gistfile1.py

 if self.state == Turner.STATE_SCANNING:
    x_disc, y_disc = int(self.x + 0.5), int(self.y + 0.5) 
    # +0.5 because axis origin is in the middle of a field

    print "Scanning on ",x_disc, " ",y_disc

    import math
    # Determine vector in which direction we are scanning
    vector = (math.cos((self.angle - 90.0)/180.0 * pi), \
math.sin((self.angle - 90.0)/180.0 * pi))

    scanned = (x_disc-round(vector[1]), y_disc + round(vector[0]))

    # Check if scanned field is not *discovered* yet
    if (x_disc-round(vector[1]+0.01), y_disc + \
round(vector[0]+0.01)) not in self.map_visited:
        if self.last_distance < 0.9:
            # Strange indexing because x runs vertically 
       # and y runs horizontally
            # Set big number so that it won't be visited
            self.map_visited[(x_disc-round(vector[1]+0.01),\
	 y_disc + round(vector[0]+0.01))] = 1000
        else:
            self.map_visited[(x_disc-round(vector[1]+0.01), \
	y_disc + round(vector[0]+0.01))] = 0

    # Keep track of scanned fields
    self.state_helper += 1


    # It means that we have reached the last rotation
    if self.state_helper == 4:
        self.command_queue.append(["STATE_CHANGE", Turner.STATE_DECIDE_NEXT])
    else:
        self.command_queue.append([TURN, int(0.5*pi / TICK_ROTATE)])
        self.angle = (self.angle + 90.0) % 360
        self.command_queue.append([SENSE_SONAR])