Tunneling program progress bar help

I have been trying to get this to work for awhile and I keep getting stuck. The code always starts to feel messy and i've barely gotten it to work in a past attempt. Hopefully someone has a better way of doing it.


I want it to be something like this. (edited from MS paint)

Spoiler

Here is the failed code that makes up my latest attempt of idk how many now. Sorry it's probably not the cleanest of code. :(/>

http://pastebin.com/B2mABBeq

I'm interested to see what people come up with.

A quick whack at the problem. Solving off-by-one errors is an exercise left to the reader.

function renderBar(current, max, label)
  local cursorX, cursorY = term.getCursorPos()
  local x, y = term.getSize()
  local center = math.floor(x / 2)
  local transition = max * x / current
  local textStart = center - math.floor(#label / 2)
  local textStop = textStart + #label
  local before, after = textStart - 1, x - textStop
  local beforeStart, afterStart = math.floor(before / 2) - math.floor(string.len(tostring(current)) / 2), math.floor(after / 2) - math.floor(string.len(tostring(after)) / 2)
  local barString = string.rep(" ", beforeStart)..tostring(current)
  barString = barString..string.rep(" ", textStart - #barString)..label
  barString = barString..string.rep(" ", afterStart - #barString)..tostring(max)
  barString = barString..string .rep(" ", x - #barString)
  local first, second = string.sub(barString, math.min(1, transition - 1), transition - 1), string.sub(barString, transition)
  term.setCursorPos(1, cursorY)
  term.setTextColor(colors.black)
  term.setBackgroundColor(colors.green)
  term.write(first)
  term.setBackgroundColor(colors.red)
  term.write(second)
end

I'm calling it like this

for i = 1, 100 do
  renderBar(i, 100, "Progress")
end

It's coming up with an error on the 3rd barString line (the one that has string.rep(" ", afterStart… )

vm error: java.lang.NegativeArraySizeException

same error when I call it like this

renderBar(1, 100, "Progress")

The math that sets afterStart should include a `+ textStop` at the end of the line. I think. If that isn't it, I'll have to look at later this evening.

It didn't error, but 1/100 makes the bar all green. I'll see if I can fix it, but odd are I probably won't be able to.

Instead of:

local transition = max * x / current

Try:

local transition = current * x / max

You might need to math.floor() that result as well.

Bomb Bloke, on 27 February 2014 - 01:52 AM said:

Instead of:

local transition = max * x / current

Try:

local transition = current * x / max

You might need to math.floor() that result as well.

That did it! Thanks a lot for both of your guy's help!