Moai: Graphics that reacts to commands via Sockets - sockets

Question

I need a program that can create pre-defined shapes on screen according to that commands I send to it via TCP.
I'm trying to listen to a port and so that I can use them. Before waiting of a command (via network) I have the commands required to create a square (I plan to change its attributes via network commands)
The problem is it is not creating any graphics or opening the window as it should be..
require "socket"
require "mime"
require "ltn12"
host = "localhost"
port = "8080"
server, error = socket.bind(host, port)
if not server then print("server: " .. tostring(error)) os.exit() end
screen=MOAISim.openWindow ( "test", 640, 640 )
viewport = MOAIViewport.new (screen)
viewport:setSize ( 640, 640 )
viewport:setScale ( 640, 640 )
layer = MOAILayer2D.new ()
layer:setViewport ( viewport )
MOAISim.pushRenderPass ( layer )
function fillSquare (x,y,radius,red,green,blue)
a = red/255
b = green/255
c = blue/255
MOAIGfxDevice.setPenColor ( a, b, c) -- green
MOAIGfxDevice.setPenWidth ( 2 )
MOAIDraw.fillCircle ( x, y, radius, 4 ) -- x,y,r,steps
end
function onDraw ( )
fillSquare(0,64,64, 0,0,255)
end
scriptDeck = MOAIScriptDeck.new ()
scriptDeck:setRect ( -64, -64, 64, 64 )
scriptDeck:setDrawCallback ( onDraw)
prop = MOAIProp2D.new ()
prop:setDeck ( scriptDeck )
layer:insertProp ( prop )
while 1 do
print("server: waiting for client command...")
control = server:accept()
command, error = control:receive()
print(command,error)
error = control:send("hi from Moai\n")
end
It is waiting of the command from client at control = server:accept() but it is not opening up the graphics window as it should.. Is there any command to force it to open or render
Thank you

Answer 1

MOAI doesn't run your scripts in a separate thread. A blocking call (server:accept) or forever loop (while true do) will block your MOAI app and it will appear to freeze while it merrily sits in your script forever.
So you have to do two things:
Use non-blocking calls. In this case, you need to set your server's timeout to 0. That makes server:accept return immediately. Check it's return value to see if you got a connection.
Put your while loop in a coroutine and yield once per iteration.
You'll need to handle the client the same way, using non-blocking calls in a coroutine loop.
function clientProc(client)
print('client connected:', client)
client:settimeout(0) -- make client socket reads non-blocking
while true do
local command, err = client:receive('*l')
if command then
print('received command:', command)
err = client:send("hi from Moai\n")
elseif err == 'closed' then
print('client disconnected:', client)
break
elseif err ~= 'timeout' then
print('error: ', err)
break
end
coroutine.yield()
end
client:close()
end
function serverProc()
print("server: waiting for client connections...")
server:settimeout(0) -- make server:accept call non-blocking
while true do
local client = server:accept()
if client then
MOAICoroutine.new():run(clientProc, client)
end
coroutine.yield()
end
end
MOAICoroutine.new():run(serverProc)

Answer 2

Set the timeout for the server socket, since the accept is a blocking call.
server:settimeout(1)

Answer 3

Thanks Mud...I found that before u replied so the following coroutine works
function threadFunc()
local action
while 1 do
stat, control = server:accept()
--print(control,stat)
while 1 do
if stat then
command, error = stat:receive()
print("Comm: ", command, error)
if command then
stat:close()
print("server: closing connection...")
break
else
break
end
--[[
error = stat:send("hi")
if error then
stat:close()
print("server: closing connection...",error)
break
end ]] --
else
break
end
end
coroutine.yield()
end
end
That was very helpful though