How to draw to screen in c++?

Question

How would I draw something on the screen ? not the console window but the entire screen, preferably with the console minimised.

Also, would it show up on a printscreen ?

Answer 1

in windows you can use the GetDC-function. just a minimalistic example:

#include 
#include 

void drawRect(){
    HDC screenDC = ::GetDC(0);
    ::Rectangle(screenDC, 200, 200, 300, 300);
::ReleaseDC(0, screenDC);
}
int main(void){
    char c;
    std::cin >> c;
    if (c == 'd') drawRect();
    std::cin >> c;
    return 0;
}

but since Windows Vista it is very slow