small boat design software

Hey I am new to the forum. I have a 14' mirror craft I want to "mod"..
While looken around the forum I notice someone had been able to (overlay) with colored lines while outlining his design, is this done with a design software program?

I have been unable to re find this again on this forum.
If any of you have seen this or it is you, could you post me some info.?

Thanks,
17ft'r

Ps: We all think its bigger, I measure and found it (the boat) is 14' not 17', but already had the handle.

I just used Paint on mine. I've seen some guys do CAD drawings.

Thanks for the info.. Thats doing what I wanted it to.

17ft'r