6 replies to this topic

[johnnic]

In my OS, I would like to be able to save different parts of your desktop/whatever and be able to load those later. Is there any way to save what is on a computer in a paint format?

[Shnupbups]

Not directly, but you could write a function to do so.

[theoriginalbit]

As Shnupbups said, not directly. However it is completely possible. A possible solution that I can think of requires you to have a screen buffer, i.e. a table that contains information about all the background colours, text colours and the characters on the screen.
Then you can loop through the buffer printing its contents to file. An easy way of writing colours out to a file is like so

local function colorToHex(col)
  --# return an empty string when it isn't a valid colour
  if not col or not tonumber(col) then
	return " "
  end
  --# reduce the colour from the 2^16 scale down to numbers 0-15
  col = math.floor( math.log(col) / math.log(2) )
  --# turn the numbers 0-15 into hexadecimal ( 0-F ... hex is 0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f )
  return string.format("%X", col)
end

Then to convert them back

local function hexToColor(hex)
  --# if there is no value, or its not a hex character
  if not hex or not tonumber(hex,16) then
	return colors.black
  end
  --# convert from 0-F to 0-15 ... we use 16 because hex is base-16
  hex = tonumber(hex, 16)
  --# return our color
  return 2^hex
end

Doing the above method creates the same file format as paint and nPaintPro.

[johnnic]

How would i make the screen a saveable string in the first place?

[TheOddByte]

Are you trying to make a screenshot program or something?
If so then you would probably need to track everything that has happened on the screen since startup because it'll need to know what has been printed etc. And the best way todo this is a coroutine function that's been run from startup or something and it stores the stuff into a table.. But idk.. Kinda hard to make this..

[theoriginalbit]

johnnic, on 03 July 2013 - 09:07 AM, said:

How would i make the screen a saveable string in the first place?

Hellkid98, on 03 July 2013 - 12:25 PM, said:

If so then you would probably need to track everything that has happened on the screen since startup because it'll need to know what has been printed etc.

theoriginalbit, on 03 July 2013 - 01:40 AM, said:

A possible solution that I can think of requires you to have a screen buffer, i.e. a table that contains information about all the background colours, text colours and the characters on the screen.

[TheOddByte]

Sorry... Didn't read that..