18 posts
Location
The Matrix
Posted 18 November 2013 - 11:56 AM
I have been working on a missile computer system with ICBM and the built in CC API for it. When you launch a missile, it does a 10 second countdown. During this countdown, I want to check for key presses of any kind and run another piece of code which asks you to enter a password to confirm the cancelling of the launch. The part I need help with, is how do I
check for a key press but not
wait for one? All my code so far looks like this:
Spoiler
local i = 0
local j = 10
local password = "hg548"
launcher = peripheral.wrap("left")
function checkForKeyPress()
while true do
local event, cancel = os.pullEvent("key")
if event == "key" then
write("Enter password to continue: ")
input = read("*")
if input == password then
print("Launch aborted. The computer will now restart.")
sleep(1)
term.clear()
term.setCursorPos(1,1)
os.reboot()
end
end
end
end
write("Confirm launch: (y/n): ")
ans = read()
if ans == "y" then
write("Enter password to continue: ")
input = read("*")
if input == password then
print("Launch confirmed.")
sleep(1)
term.clear()
term.setCursorPos(1,1)
for i=1, 100 do
print("Security checking..." .. i .. "%")
sleep(0.05)
term.clear()
term.setCursorPos(1,1)
end
while j~=0 do
print("Launching in " .. j .. " seconds")
sleep(1)
term.clear()
term.setCursorPos(1,1)
--parallel.run(checkForKeyPress)
j = j-1
end
launcher.launch()
os.reboot()
else
print("Password incorrect. The computer will now restart")
sleep(1)
term.clear()
term.setCursorPos(1,1)
os.reboot()
end
end
if ans == "n" then
print("Launch cancelled. The computer will now restart")
sleep(1)
term.clear()
term.setCursorPos(1,1)
os.reboot()
end
8543 posts
Posted 18 November 2013 - 02:12 PM
Don't sleep. Listen for timer and key events and start timers as necessary instead.
18 posts
Location
The Matrix
Posted 20 November 2013 - 07:54 AM
And how would I go about that? I looked on the wiki, but it wasn't much help. Sorry, I'm a bit of a Lua noob at the moment…
1610 posts
Posted 20 November 2013 - 09:45 AM
Here's a snippet I wrote on the fly (on my iPad, might not be formatted correctly)
--Ten second countdown with canceling by pressing "C"
local t = 10 --Change to amount of time if you need to.
local cancel = "c" --Change to cancel key
os.startTimer(1)
while true do
local event, a = os.pullEvent()
if event == "timer" then
t = t - 1
if t == 0 then break else os.startTimer(1) end
elseif event == "char" and a == cancel then
break
end
end
if t == 0 then
--Do stuff
else
--Launch cancelled
end
Haven't tested this but it should work fine.
To have a cancel password, look into the parallels API. (It's built into CC)
Edit: Fixed the elseif statement
Edit 2: Please indent your code :(/>
Edited on 20 November 2013 - 08:55 AM
18 posts
Location
The Matrix
Posted 20 November 2013 - 10:16 AM
Edit 2: Please indent your code :(/>
Sorry, it seemed to unformat itself when I uploaded it. Testing the code out now.
7083 posts
Location
Tasmania (AU)
Posted 20 November 2013 - 04:35 PM
Bear in mind that timers can potentially be started by other sources. When you start one, it's best to record
which timer it is, so you can be
sure that's the one expiring.
Eg,
local myTimer = os.startTimer(1)
if event == "timer" and a == myTimer then
if t == 0 then break else myTimer = os.startTimer(1) end
1610 posts
Posted 21 November 2013 - 08:55 AM
Bear in mind that timers can potentially be started by other sources. When you start one, it's best to record
which timer it is, so you can be
sure that's the one expiring.
Eg,
local myTimer = os.startTimer(1)
if event == "timer" and a == myTimer then
if t == 0 then break else myTimer = os.startTimer(1) end
Didn't know they returned anything on start :P/>