程式語言 - X Window (X11) - C/C++ - Draw Point

參考資訊：
https://github.com/QMonkey/Xlib-demo
https://people.scs.carleton.ca/~claurend/Courses/COMP2401/Notes/COMP2401_Ch8_Graphics.pdf

main.c

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <X11/Xlib.h>
  
int main(int argc, char *argv[])
{
    GC gc = 0;
    int i = 0;
    Window win = 0;
    Display *display = NULL;
    XPoint pt[3] = { {10, 200}, {10, 201}, {10, 202} };
  
    display = XOpenDisplay(NULL);
    win = XCreateSimpleWindow(
        display,
        RootWindow(display, 0),
        0,
        0,
        320,
        240,
        0,
        0,
        0xffffff);
  
    XStoreName(display, win, "main");
    gc = XCreateGC(display, win, 0, NULL);
    XMapWindow(display, win);
    XFlush(display);
    usleep(100000);
  
    XSetForeground(display, gc, 0);
    for (i = 0; i < 100; i++) {
        XDrawPoint(display, win, gc, i, i);
    }
    XDrawPoints(display, win, gc, pt, 3, CoordModeOrigin);
    XFlush(display);
    usleep(3000000);
  
    XUnmapWindow(display, win);
    XDestroyWindow(display, win);
    XCloseDisplay(display);
  
    return 0;
}

編譯、測試

$ gcc main.c -o main -lX11
$ ./main