quick fix and instructions for the ledfloor mqtt clinet

mqttclient.py

"""
## Usage

- publish to MQTT topic "ledfloorupdates" to change the color(s) of the LED floor
- send a string of the shape "x y r g b" to change the color of an individual pixel x,y to RGB(r,g,b)
- send a string of the shape "r g b" to change the color of all pixes to RGB(r,g,b)

## Starting the Server
- start the Raspberry Pi
- ssh pi@10.90.154.80
- cd telefloor
- source env/bin/activate (to activate pythin virtual environment)
- sudo killall python (to kill other scripts using the floor)
- sudo python mqttclient.py

## ToDo
- The script on the Pi is actually using GRB, not RGB at the moment. 
- the script on the Pi is currently not able to set an individual pixel

I changed this here (in `mqttclient.py`), but You have to update the code on the Pi and test it. I probably made a mistake 
"""

import paho.mqtt.client as mqtt
from neopixel import *
import argparse
import time

# LED strip configuration:
LED_COUNT      = 122      # Number of LED pixels.
LED_PIN        = 18      # GPIO pin connected to the pixels (18 uses PWM!).
LED_FREQ_HZ    = 800000  # LED signal frequency in hertz (usually 800khz)
LED_DMA        = 10      # DMA channel to use for generating signal (try 10)
LED_BRIGHTNESS = 255     # Set to 0 for darkest and 255 for brightest
LED_INVERT     = False   # True to invert the signal (when using NPN transistor level shift)
LED_CHANNEL    = 0       # set to '1' for GPIOs 13, 19, 41, 45 or 53
LED_STRIP      = neo.ws.WS2811_STRIP_GRB 


# Define functions which animate LEDs in various ways.
def colorWipe(strip, color, wait_ms=50):
    """Wipe color across display a pixel at a time."""
    for i in range(strip.numPixels()):
        strip.setPixelColor(i, color)
        strip.show()
        time.sleep(wait_ms/1000.0)


def pos_to_led_nr(x, y):
        """ convert [x,y] coordinates into corresponding LED number
        """
        width     = 11
        height    = 11
        flip_axes = False
        flip_x    = True
        flip_y    = False

        x = x if not flip_axes else y
        y = y if not flip_axes else x
        xpos = x if not flip_x else (width) - (x+1)
        ypos = y if not flip_y else (height) - (y+1)
        assert x <= width and y <= height
        
        led_nr = int(ypos * self.height) + int(xpos)
        return led_nr 


def parse_updates(msg):
    lines = msg.splitlines()

    print("--- Start of Update ---")
    updates = [line.split(' ') for line in lines]
    for u in updates:
        if len(u) == 5:
            try:
                u = [int(c) for c in u]
                print("setting ({},{}) to RGB({},{},{})".format(*u))
                # TODO: quick fix, test and streamline
                x = u[0]
                y = u[1]
                rgb = Color(u[2], u[3], u[4])
                led_nr = pos_to_led_nr(x,y)
                strip.setPixelColor(led_nr, rgb) 
            except:
                print("Error.")
        elif len(u) == 3:
            try:
                u = [int(c) for c in u]
                print("setting floor to RGB({},{},{})".format(*u))
                colorWipe(strip, Color(*u))    
            except:
                print("Error.")           
        else:
            print("(Invalid Command)" + str(u))
    print("--- End of Update ---")
    strip.show()


def on_connect(client, userdata, flags, rc):
     print("Connected With Result Code {}".format(rc))
     client.subscribe("ledfloorupdates")


def on_disconnect(client, userdata, rc):
	print("Disconnected From Broker")


def on_message(client, userdata, message):
    msg = message.payload.decode()
    parse_updates(msg)
	#print(message.topic)



# Set up LED strip
strip = Adafruit_NeoPixel(LED_COUNT, LED_PIN, LED_FREQ_HZ, LED_DMA, LED_INVERT, 
    LED_BRIGHTNESS, LED_CHANNEL, LED_STRIP)

strip.begin()

# Set up MQTT client
broker_address = "localhost"
broker_port = 1883
client = mqtt.Client()

#Assigning the object attribute to the Callback Function
client.on_connect = on_connect
client.on_disconnect = on_disconnect
client.on_message = on_message

client.connect(broker_address, broker_port)
client.loop_forever() # Note: is non-blocking

print ('Press Ctrl-C to quit.')