"""A simple simulator for the OPC LED panels.
Usage: python simulator.py
To make the LED-bot talk to this server, change the server address to
`localhost:7890` in your configuration.
"""
from struct import unpack
import SocketServer
W = 64
H = 32
led_num = W * H
led_width = led_height = led_spacing = 3
screen_width = W * (led_width + led_spacing) + led_spacing
screen_height = H * (led_height + led_spacing) + led_spacing
header = 'B' * 4
udp_format = header + ''.join('B' for _ in xrange(led_num * 3))
class OPCHandler(SocketServer.BaseRequestHandler):
"""
The RequestHandler class for our server.
It is instantiated once per connection to the server, and must
override the handle() method to implement communication to the
client.
"""
def handle(self):
# self.request is the TCP socket connected to the client
data = self.request.recv(4096*32).strip()
values = unpack(udp_format, data)
# reverse the data, since we do the craziness in our client.
values = values[::-1][:-4]
screen = self.server.screen
for h in range(H):
for w in range(W):
i = (h*W + w) * 3
fill = '#%02x%02x%02x' % values[i:i+3]
left = led_spacing + w * (led_width + led_spacing)
top = led_spacing + h * (led_height + led_spacing)
screen.create_rectangle(
left, top, left+led_width, top+led_height, fill=fill
)
screen.update()
class OPCServer(SocketServer.TCPServer):
allow_reuse_address = True
def __init__(self, server_address, RequestHandlerClass, bind_and_activate=True):
SocketServer.TCPServer.__init__(self, server_address, RequestHandlerClass, bind_and_activate)
self.screen = get_canvas()
self.screen.update()
def get_canvas():
""" Creates a Tkinter canvas. """
from Tkinter import Tk, Canvas, BOTH
root = Tk()
root.title('LED bot simulator')
root.geometry("%sx%s" % (screen_width, screen_height))
canvas = Canvas(root)
canvas.pack(fill=BOTH, expand=1)
canvas.create_rectangle(
0, 0, screen_width, screen_height, outline="#000", fill="#000"
)
return canvas
if __name__ == "__main__":
HOST, PORT = "localhost", 7890
# Create the server
server = OPCServer((HOST, PORT), OPCHandler)
# Start the server; Interrupt with Ctrl-C
server.serve_forever()
