5.7. Your second X Program 5.7. Your second X Program You can now create an X Window System program which
draws(see later to retrieve it):
#include <X11/Xlib.h>
#include <stdio.h>
#include <X11/Xutil.h>
#include <math.h>
main (argc, argv)
int argc;
char **argv;
{
Display *myDisplay;
int myScreen;
int myDepth;
XSetWindowAttributes myWindowAttributes;
unsigned long myWindowMask;
Window myWindow;
XSizeHints theSizeHints;
GC myGC;
unsigned long myWhitePixel;
unsigned long myBlackPixel;
XGCValues myGCValues;
unsigned long myValueMask;
int i;
double twopi= 8.0*atan(1.0);
int x = 200; /* x top left corner of window */
int y = 150; /* y top left corner of window */
unsigned int width = 850; /* width of the window */
unsigned int height = 700; /* height of the window */
int border_width = 20; /* border width of the window */
/*--------------- Pre-assigned points for XDrawLines call below---------------*/
static XPoint points1[]=
{
499,214,489,224,484,229,479,239,474,254,479,274,489,279,499,279,
509,274,519,264
};
static XPoint points2[]=
{
499,284,504,289,509,289,514,289,519,284
};
static XPoint points3[]=
{
514,214,509,214,514,219,519,219,514,214
};
static XPoint points4[]=
{
484,209,479,214,479,214,484,214,489,209,484,209
};
static XPoint points5[]=
{
514,199,529,214,539,224,539,244,539,259,539,264,534,279,534,274
};
static XPoint points6[]=
{
519,194,529,204,544,219,544,239
};
static XPoint points7[]=
{
484,194,494,194,504,199,509,199
};
static XPoint points8[]=
{
489,189,494,189,509,189
};
static XPoint points9[]=
{
494,179,509,179,514,184,514,189
};
static XPoint points10[]=
{
524,189,534,199,549,209,554,229,549,249,549,259,549,279,549,284
};
/*--------End of Pre-assigned points for XDrawLines call below---------------*/
myDisplay = XOpenDisplay ("");
if (myDisplay == NULL)
{
fprintf (stderr,
"ERROR: Could not open a connection to X on display %s\n",
XDisplayName (NULL));
exit (0);
}
myScreen = DefaultScreen (myDisplay);
myDepth = DefaultDepth (myDisplay, myScreen);
myWhitePixel = WhitePixel (myDisplay, myScreen);
myBlackPixel = BlackPixel (myDisplay, myScreen);
/* border colour */
myWindowAttributes.border_pixel = BlackPixel (myDisplay, myScreen);
/* background colour */
myWindowAttributes.background_pixel = WhitePixel (myDisplay, myScreen);
/* if window manager intervenes or not */
myWindowAttributes.override_redirect = True;
/* create mask for attributes */
myWindowMask = CWBackPixel | CWBorderPixel | CWOverrideRedirect;
myWindow = XCreateWindow (myDisplay,
RootWindow (myDisplay, myScreen),
x, y, width, height, border_width,
myDepth, InputOutput, CopyFromParent,
myWindowMask, &myWindowAttributes);
theSizeHints.flags = PPosition | PSize; /* set mask for the hints */
theSizeHints.x = x; /* x position */
theSizeHints.y = y; /* y position */
theSizeHints.width = width; /* width of the window */
theSizeHints.height = height; /* height of the window */
XSetWMNormalHints (myDisplay, myWindow, &theSizeHints);
myGC = XCreateGC (myDisplay,
myWindow,
(unsigned long) 0,
&myGCValues);
/* error... cannot create gc */
if (myGC == 0)
{
XDestroyWindow(myDisplay, myScreen);
exit (0);
}
/* set forground and background defaults */
else
{
XSetForeground (myDisplay, myGC, myBlackPixel);
XSetBackground (myDisplay, myGC, myWhitePixel);
}
XMapWindow (myDisplay, myWindow);
XDrawRectangle (myDisplay, myWindow, myGC,
100, 100, 50, 50 );
XFillRectangle (myDisplay, myWindow, myGC,
200, 100, 50, 50 );
/* draws a circle */
XDrawArc (myDisplay, myWindow, myGC,
300, 100, 50, 50 , 0, 360*64);
XFillArc (myDisplay, myWindow, myGC,
400, 100, 50, 50 , 0, 360*64);
/* draws an oval */
XDrawArc (myDisplay, myWindow, myGC,
500,100, 60, 40 , 0, 360*64);
XFillArc (myDisplay, myWindow, myGC,
600,100, 60, 40 , 0, 360*64);
/* draws an arc */
XDrawArc (myDisplay, myWindow, myGC,
100, 300, 60, 40 , 90*64, 180*64);
XFillArc (myDisplay, myWindow, myGC,
200, 300, 60, 40 , 90*64, 180*64);
#define RAYS 10
for(i=0;i<RAYS/2;i++)
XDrawLine(myDisplay, myWindow, myGC,
325+(int)25*cos(twopi/RAYS*i),
325+(int)25*sin(twopi/RAYS*i),
325+(int)25*cos(twopi/2.0+twopi/RAYS*i),
325+(int)25*sin(twopi/2.0+twopi/RAYS*i));
XDrawLines(myDisplay, myWindow, myGC,
points1,sizeof(points1)/sizeof(points1[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points2,sizeof(points2)/sizeof(points2[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points3,sizeof(points3)/sizeof(points3[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points4,sizeof(points4)/sizeof(points4[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points5,sizeof(points5)/sizeof(points5[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points6,sizeof(points6)/sizeof(points6[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points7,sizeof(points7)/sizeof(points7[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points8,sizeof(points8)/sizeof(points8[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points9,sizeof(points9)/sizeof(points9[0]),CoordModeOrigin);
XDrawLines(myDisplay, myWindow, myGC,
points10,sizeof(points10)/sizeof(points10[0]),CoordModeOrigin);
XFlush (myDisplay);
sleep(10);
XDestroyWindow (myDisplay, myWindow);
XCloseDisplay (myDisplay);
exit (0);
}
LOCAL_LIBRARIES = $(XLIB) -lm
FILE = simplewindow
SRCS = $(FILE).c
OBJS = $(FILE).o
ComplexProgramTarget($(FILE))
) and compile it on your machine.
Imakefile draw.c After retrieving and saving the code plus Imakefile, you
should be able to type:
xmkmf -a ; make FILE=draw
This will produce the executable called draw.
It is possible to execute a (different) draw program and display it on your screen. To run it, your system must be running X and the server control is set to xhost www.cs.curtin.edu.au/. Also it will not work if you are using a proxy server or you are running your browser on a machine different from the one you are displaying it on. Many example programs are available
