CarSimulation.py

from random import randint,sample,random
from time import sleep
import os, platform

MAX_VELOCITY = 9
MAX_CARS_PER_ROAD=10 #Can change this, always < ROAD_SIZE
P_RANDOM_STOP = 0.15 #Probab Car reduces velocity randomly
MAX_ROA = 1.0 #Rate of Appearance 
EMPTY_CHAR = '.'
WAIT_BETWEEN_SIMULATIONS = 1 #Seconds

def cleanConsole():
    try:
        if platform.system() == "Windows": 
            os.system('cls') 
        else: 
            os.system('clear')
    except: 
        pass

class Car:
    def __init__(self, velocity, xPosition,yPosition, coordinator):
        self.velocity = velocity
        self.updatePos(yPosition,xPosition)
        self.coordinator = coordinator

    def changeSpeed(self):
        ncr = self.nextCarInRange() #Check next car position whitin our range(velocity)
        if ncr == 0: #We can accelerate, no cars
            if self.velocity < MAX_VELOCITY:
                self.velocity+=1
        else: #Slow down and finish
            self.velocity = ncr - 1
        
        #Probability of slowing down 1 Only if car is moving
        if self.velocity>0 and random()<P_RANDOM_STOP: 
            self.velocity -= 1
            # print "RED: [%s,%s]"%(self.y,self.x)
        
        
    def updatePos(self,y,x):
        self.y = y
        self.x = x

    def move(self):
        if self.velocity == 0: return #No need to move
        self.coordinator.setInPlace(self,self.y,self.x+self.velocity)

    #Si regresa 0 entonces si nos podemos mover,
    #Si regresa cualquier otro numero entonces no, es la posicion del prox coche
    def nextCarInRange(self):
        for i in range(self.velocity+1):
            if not self.coordinator.isAvailable(self.y,self.x+i+1): #Solo avanzan en X
                return i+1 #Nos regresa la distancia hacia el proximo Coche
        return 0
    
    def __str__(self):
        return str(self.velocity)

class Playground:
    def __init__(self, ROAD_DISTANCE, NUM_ROADS, NEW_CARS_APPEARANCE_PROBABILITY=0):
        self.ROAD_DISTANCE = ROAD_DISTANCE
        self.NUM_ROADS = NUM_ROADS
        self.NEW_CARS_APPEARANCE_PROBABILITY = NEW_CARS_APPEARANCE_PROBABILITY
        self.velocities = 0 #Summed velocities
        self.totalCars = 0
        self.initPlayground()
        self.printPlayground()
        
    def initPlayground(self):
        emptyRoad = [EMPTY_CHAR]*self.ROAD_DISTANCE
        emptyAvenue = [ emptyRoad[:] for _ in range(self.NUM_ROADS) ]        

        for i in range(self.NUM_ROADS):
            #CALCULATE INITIAL CARS POSITIONS
            cars_pos = sample( range(0,self.ROAD_DISTANCE), randint(1,MAX_CARS_PER_ROAD) )
            #ADD EACH VELOCITY to THE CORRESPONDING CELL
            for val in cars_pos:
                emptyAvenue[i][val] = Car( randint(0,MAX_VELOCITY) , val,i, self) 
                self.totalCars += 1

        self.avenue = emptyAvenue
        
    def isAvailable(self,y,x):
        if y >= self.NUM_ROADS or x >= self.ROAD_DISTANCE:
            return True
        
        return self.avenue[y][x] == EMPTY_CHAR
    
    def setInPlace(self,car,y,x): #ys mayores haran que truene o car.y/car.x wrong coordinates
        if x >= self.ROAD_DISTANCE: #The car left the road
            self.avenue[car.y][car.x] = EMPTY_CHAR
            self.totalCars -= 1
            return #Maybe add another car

        if self.avenue[y][x] != EMPTY_CHAR:  #DEBUG ERRORS
            print "ERR: [%s,%s] %s -> [%s,%s]"%(car.y,car.x,car.velocity,y,x) 
        
        self.avenue[y][x] = car                #Move to new position
        self.avenue[car.y][car.x] = EMPTY_CHAR #Delete old position
        car.updatePos(y,x)                     #Update, succesfull movement
    
    def carsActions(self):
        self.velocities = 0.0 #Hack, usaremos para average speed
        #Primero que todos cambien velocidad
        for road in self.avenue:
            for car in road:
                if car != EMPTY_CHAR:
                    car.changeSpeed()
                    self.velocities += float(car.velocity) #Temporal

        #Despues que todos se muevan
        for road in self.avenue:
            for car in reversed(road): #Mover de derecha a izq
                if car != EMPTY_CHAR:
                    car.move()

    def dispatchCars(self):
        for i,road in enumerate(self.avenue):
            #If we can add & % tells us to add
            if road[0]==EMPTY_CHAR and random()<self.NEW_CARS_APPEARANCE_PROBABILITY:
                road[0] = Car( randint(0,MAX_VELOCITY) ,0,i, self) 
                self.totalCars += 1

    def showMenu(self):
        c = "r"
        while c != "q":
            self.printPlayground()
            c = raw_input("Press the key for any action:\n\tq\tExit\n\tw\t-ROA\n\te\t+ROA\n\tr\tResume\nYour Choice: ")
            
            if c == "w":
                self.decreaseTraffic()
            elif c == "e":
                self.increaseTraffic()
            elif c == "r" or c == "q":
                break
            else:
                print "Wrong Input"
        
        if c == "r":
            self.startSimulation()            
        else:
            print "Bye!"

    def startSimulation(self):
        try:
            while True:
                self.carsActions()  #Accelerate/Move
                self.dispatchCars() #Appear New Cars
                self.printPlayground()
                sleep(WAIT_BETWEEN_SIMULATIONS)
        except KeyboardInterrupt:
            self.showMenu()
    
    def printPlayground(self):
        cleanConsole()
        print
        for road in self.avenue:
            for cell in road:
                print cell,
            print
        print
        self.printStats()

    def printStats(self):
        print "Number of Roads: %s, Road Size: %s"%(self.NUM_ROADS,self.ROAD_DISTANCE)
        print "Cars rate of appearance: %s"%self.NEW_CARS_APPEARANCE_PROBABILITY
        print "Probability car reduces speed randomly: %s"%P_RANDOM_STOP
        print "Number of Cars %s"%self.totalCars
        print "Average Velocity %s"%(0 if self.totalCars<=0 else self.velocities/float(self.totalCars)) 
        print "\nPress 'Ctrl + C' for more\n"

    def increaseTraffic(self):
        self.NEW_CARS_APPEARANCE_PROBABILITY+=0.05
        if self.NEW_CARS_APPEARANCE_PROBABILITY>MAX_ROA: self.NEW_CARS_APPEARANCE_PROBABILITY = MAX_ROA
    
    def decreaseTraffic(self):
        self.NEW_CARS_APPEARANCE_PROBABILITY-=0.05
        if self.NEW_CARS_APPEARANCE_PROBABILITY<0.05: self.NEW_CARS_APPEARANCE_PROBABILITY = 0

if __name__=="__main__":
    pg = Playground(100,30)
    pg.showMenu()