How to plot data from UDP stream coming from F1 2019 game, my lineplot comes up blank

Question

I have this below code in which I am getting data packets from UDP from the game. However, when running this code I am getting a blank plot, I want to plot Speed Vs Time here and I want to see what interesting visualization comes up while I drive in corners. Any help or pointer is much appreciated.

Code -

import time

import socket
import rawutil
import matplotlib.pyplot as plt
plt.ion()
import seaborn as sns

from f1_2019_telemetry.packets import unpack_udp_packet

# udp_socket = socket.socket(family=socket.AF_INET, type=socket.SOCK_DGRAM)
# udp_socket.bind(('', 20777))

# while True:
#     udp_packet = udp_socket.recv(2048)
#     packet = unpack_udp_packet(udp_packet)
#     print("Received:", packet)

listen_socket = socket.socket(family=socket.AF_INET, type=socket.SOCK_DGRAM)
listen_socket.bind(('', 20777))
while True:
  x = int(round(time.time()*1000))
  print(x)
  # Receiving data
  data, address = listen_socket.recvfrom(2048)
  header = data[:20]
  telemetry = data[20:]

  # decode the header
  packetFormat, = rawutil.unpack('<H', header[:2])
  gameMajorVersion, = rawutil.unpack('<B', header[2:3])
  gameMinorVersion, = rawutil.unpack('<B', header[3:4])
  packetVersion, = rawutil.unpack('<B', header[4:5])
  packetId, = rawutil.unpack('<B', header[5:6])
  sessionUID, = rawutil.unpack('<Q', header[6:14])
  sessionTime, = rawutil.unpack('<f', header[14:18])
  frameIdentifier, = rawutil.unpack('<B', header[18:19])
  playerCarIndex, = rawutil.unpack('<B', header[19:20])

  # print all info (just for now)

##  print('Packet Format : ',packetFormat)
##  print('Game Major Version : ',gameMajorVersion)
##  print('Game Minor Version : ',gameMinorVersion)
##  print('Packet Version : ',packetVersion)
##  print('Packet ID : ', packetId)
##  print('Unique Session ID : ',sessionUID)
##  print('Session Time : ',sessionTime)
##  print('Frame Number : ',frameIdentifier)
##  print('Player Car Index : ',playerCarIndex)
##  print('\n\n')

#start getting the packet data for each packet starting with telemetry data

  if (packetId == 6):
    speed, = rawutil.unpack('<H' , telemetry[3:5])
    throttle, = rawutil.unpack('<f' , telemetry[4:8])
    steer, = rawutil.unpack('<f' , telemetry[8:12])
    brake, = rawutil.unpack('<f' , telemetry[12:16])
    gear, = rawutil.unpack('<b' , telemetry[17:18])
    rpm, = rawutil.unpack('<H' , telemetry[18:20])

    print (speed)

    y = speed
    plt.xlabel("Nanos")
    plt.ylabel("Speed")
    # sns.lineplot(x,int(y))
    # plt.scatter(x,y)
    lines = plt.plot(x,y)
    plt.draw()
    plt.setp(lines, color='r', linewidth=2.0)
    plt.pause(0.1)

plt.show(block=True)

Answer 1

Hi you may have solved the problem on your own, but if not i hope this can help. I ran your code and the problem seems to be, that you are not saving the data and the plot just has one data point. Try creating a list (L=[]) and then L.append(speed). Do the same with time and plot the list(one list for each axis).