Pixeling

[GEAR_2012]

Hi.

Can anyone help to me?
I need a turbo pascal code to coloring the screen to a choosen color randomly by pixel by pixel.  My problem is how do not put pixel to there where already I have.

Sorry for my poor english.
Thanks for any answer.

[jamie]

If you are trying to save CPU time, you aren't going to gain much, actually you may even cause more delay because you
would need to first test what is there currently before writing a new value...

 Or could it be you need to simply address the points in a loop manner ?

 For X := 0 to 320 do
   For Y := 0 to 240 do
      SetColor(X,Y, Random(…..));

 That is just a conceptional thought.

[Martin_fr]

You mean something like flood fill? https://en.wikipedia.org/wiki/Flood_fill

[GEAR_2012]

How can I check if the pixel is already colored?

[lucamar]

How can I check if the pixel is already colored?

It depends on quite a lot of things, among them: What OS is it for? Console app or GUI? What pixel type? Direct access to screen or through library code? If library, which one? How are you coloring the pixels? etc., etc.

[Martin_fr]

Maybe use "paint" program. (And screen shot)
Draw an example what it looks at start.
And then what you want it to look after.