Image File Viewer

local tArgs = {...}
if #tArgs < 1 then
  error("Usage: view <image filename>")
end
if not fs.exists(tArgs[1]) then
  error("Not an image file")
end
image = paintutils.loadImage(tArgs[1])
local w, h = term.getSize()
local imgW = 0
local imgH = 0
local imgWMax = 0
for i, v in pairs(image) do
  imgH = imgH + 1
  imgW = 0
  for k, e in pairs(v) do
    imgW = imgW + 1
    if imgW > imgWMax then
      imgWMax = imgW
    end
  end
end
imgW = imgWMax
drawX = w / 2 - imgW / 2 + 1
drawY = h / 2 - imgH / 2 + 1
local begin = true
while true do
  term.setBackgroundColor(colors.black)
  term.setTextColor(colors.white)
  term.clear()
  paintutils.drawImage(image, drawX, drawY)
  if begin then
    term.setBackgroundColor(colors.black)
    term.setTextColor(colors.white)
    term.setCursorPos(1, h)
    term.write("Arrow keys to move, Ctrl to quit")
  end
  events = {os.pullEvent()}
  if events[1] == "key" then
    if events[2] == 200 then
      drawY = drawY + 1
      begin = false
    elseif events[2] == 205 then
      drawX = drawX - 1
      begin = false
    elseif events[2] == 208 then
      drawY = drawY - 1
      begin = false
    elseif events[2] == 203 then
      drawX = drawX + 1
      begin = false
    elseif events[2] == 29 then
      term.setBackgroundColor(colors.black)
      term.setTextColor(colors.white)
      term.clear()
      term.setCursorPos(1, 1)
      break
    end
    sleep(.1)
  end
end