SetStandardHints(Display * display, Window window, char app_name[], char
wind_name[], int x, int y, int width, int height)
{
SetSizeHints(display, window, x, y, width, height);
SetWindowName(display, window, wind_name);
SetClassHints(display, window, app_name, APP_CLASS);
SetWMHints(display, window, NormalState);
}
// main entry point
main(int argc, char **argv)
{
// get command line options
int nextarg;
if (cmdopts(argc, argv, nextarg) != OK)
{
fprintf(stderr, "invalid command line option [%s].\n",
argv[nextarg]);
return(2);
}
// get data
if (getdata(argc, argv, nextarg) != OK)
{
fprintf(stderr, "unable to get data.");
return(2);
}
// connect to server
Display *xdisplay = NULL;
if (OpenDisplay(display, xdisplay) != OK)
{
fprintf(stderr, "unable to open display to server %s.\n",
XDisplayName(display));
return(2);
}
// get physical screen attributes
int xscreen;
unsigned int display_width, display_height;
if (GetDisplayAttributes(xdisplay, xscreen,
display_width, display_height) != OK)
{
fprintf(stderr, "unable to get display attributes.\n");
CloseDisplay(xdisplay);
return(2);
}
// determine window geometry and location
int window_width, window_height, window_x, window_y;
if (GetWindowGeometry(display_width, display_height,
window_width, window_height,
window_x, window_y) != OK)
{
fprintf(stderr, "unable to get window geometry.\n");
CloseDisplay(xdisplay);
return(2);
}
// default black and white pixels
unsigned long black = BlackPixel(xdisplay, xscreen);
unsigned long white = WhitePixel(xdisplay, xscreen);
// get pseudo-color display, if any
int window_depth;
Visual *window_visual;
if (GetPseudoColorVisual(xdisplay, xscreen,
window_visual, window_depth) != OK)
{
fprintf(stderr, "unable to get a color visual.\n");
CloseDisplay(xdisplay);
return(2);
}
// create a window
unsigned int window_border_width = 4;
Window root_window = RootWindow(xdisplay, xscreen);
window_visual=CopyFromParent;
window_depth=CopyFromParent;
Window window = CreateWindow(
xdisplay, root_window,
window_x, window_y, window_width, window_height,
black, white, EventMask,
window_visual, window_border_width, window_depth);
// set size hints
if (SetSizeHints(xdisplay, window,
window_x, window_y, window_width, window_height) != OK)
{
fprintf(stderr, "unable to set window size hints.\n");
CloseDisplay(xdisplay);
return(2);
}
// set window name
if (SetWindowName(xdisplay, window, title) != OK)
{
fprintf(stderr, "unable to set window title.\n");
CloseDisplay(xdisplay);
return(2);
}
// set class hints
if (SetClassHints(xdisplay, window, argv[0], argv[0]) != OK)
{
fprintf(stderr, "unable to set class hints.\n");
CloseDisplay(xdisplay);
return(2);
}
// set other window manager hints
int initstate =
(strcmp(iconic, "YES") == 0) ? IconicState : NormalState;
if (SetWMHints(xdisplay, window, initstate) != OK)
{
fprintf(stderr, "unable to set WM hints.\n");
CloseDisplay(xdisplay);
return(2);
}
// set up color map for window
Colormap window_colormap;
if (SetUpColorMap(xdisplay, xscreen,
window, window_visual, window_colormap) != OK)
{
fprintf(stderr, "unable to set up a color map.\n");
CloseDisplay(xdisplay);
return(2);
}
// allocate colors for background and foreground
unsigned long window_background =
AllocateColorByName(xdisplay, window_colormap,
background, white);
unsigned long window_foreground =
AllocateColorByName(xdisplay, window_colormap,
foreground, black);
// get font for writing
XFontStruct *xfont = LoadFont(xdisplay, font, "fixed");
if (xfont == NULL)
{
fprintf(stderr, "unable to load font.\n");
CloseDisplay(xdisplay);
return(2);
}
// create GC for drawing
GC gc = CreateGC(xdisplay, window, xfont,
window_foreground, window_background);
GC xor_gc = CreateXorGC(xdisplay, window, xfont,
window_foreground, window_background);
// map window
XMapRaised(xdisplay, window);
XFlush(xdisplay);
// event loop
int start_x = -1;
int start_y = -1;
int last_x = -1;
int last_y = -1;
XEvent event;
KeySym keysym;
char string[BUFSIZ];
for (int done = 0; !done; )
{
XNextEvent(xdisplay, &event);
switch (event.type)
{
case Expose:
if (event.xexpose.count == 0)
{
redraw(xdisplay, window, gc, xfont,
window_width, window_height);
}
break;
case ConfigureNotify:
window_x = event.xconfigure.x;
window_y = event.xconfigure.y;
window_width = event.xconfigure.width;
window_height = event.xconfigure.height;
break;
case KeyPress:
done = DecodeKeyPress(&event.xkey, &keysym, string);
break;
case MappingNotify:
XRefreshKeyboardMapping(&event.xmapping);
break;
case ButtonPress:
if (event.xbutton.button == Button1)
{
start_x = event.xbutton.x;
start_y = event.xbutton.y;
last_x = start_x;
last_y = start_y;
DrawBox(xdisplay, window, xor_gc,
start_x, start_y, last_x, last_y);
XFlush(xdisplay);
}
break;
case ButtonRelease:
if (event.xbutton.button == Button1)
{
if (start_x != last_x && start_y != last_y)
{
DrawBox(xdisplay, window, xor_gc,
start_x, start_y,
last_x, last_y);
XFlush(xdisplay);
UpdateLimits(start_x, start_y,
last_x, last_y,
window_width, window_height);
XClearWindow(xdisplay, window);
XFlush(xdisplay);
redraw(xdisplay, window, gc, xfont,
window_width, window_height);
XFlush(xdisplay);
}
start_x = -1;
start_y = -1;
last_x = -1;
last_y = -1;
}
else
{
// reset to original values.
rminxval = reset_rminxval;
rmaxxval = reset_rmaxxval;
rminyval = reset_rminyval;
rmaxyval = reset_rmaxyval;
XClearWindow(xdisplay, window);
XFlush(xdisplay);
redraw(xdisplay, window, gc, xfont,
window_width, window_height);
XFlush(xdisplay);
}
break;
case MotionNotify:
if (event.xbutton.button == Button1)
{
DrawBox(xdisplay, window, xor_gc,
start_x, start_y, last_x, last_y);
last_x = event.xmotion.x;
last_y = event.xmotion.y;
DrawBox(xdisplay, window, xor_gc,
start_x, start_y, last_x, last_y);
XFlush(xdisplay);
}
break;
}
}
// close display
CloseDisplay(xdisplay);
// all done
return(0);
}
