I'm having to write a program for my computer science class at school that gathers two numbers from the user, one being a "country code" and the other a width dimension. The program will then create an image of the country's corresponding flag with the width being what the user specified. The three countries are France, Germany and Lithuania.
But anyways I've got the concept down and have a basic outline written but I was wondering when printing individual pixels does it print horizontally or vertically. I was wondering because with the way the flags look I will have to use a conditional statement to switch the RGB values as the colors change on the flags.
You may be interested in the curses lib. It will allow you to do many fancy things to the terminal/command prompt window like adding colors, using special characters. I recommend pdcurses. Download cmake and build it from source. Build the examples too so you can see what the lib is capable of. Back in the day I made some pretty cool games with nothing but C and Curses. Oh and by the way! pdcurses is cross platform and has fantastic documentation and tutorials. It's own API resembles much that of the standard C io!
(I like curses and CLI programs..)
Assuming you have a window to work with and not just a command prompt/terminal then you'd probably want to use OpenGL to create the flag and color it, which is trivial (unless you are making the US flag..)