Conference bulova::decw_jan-89_to_nov-90

2674.0. "Draw lines on FireFox" by TAVHLT::DORON (Doing my BEST !!!) Fri Apr 27 1990 02:47

Hi There !

	We have a customer who is interested in a large purchase 
	of Firefox systems ( approxiamtely $1M of equipment ).

	Unfortunately the customer in one of his benchmarks uncovered
	a bug in the Firfox server which follows.

	The program is written under VMS 5.3-1. The machine is VS3540.

	The program displays various line types at various line lengths.
	For example a line displayed across the screen is composed of 
	individual polyline line segments. The problem occurs when 
	displaying more than 200 line segments as a single line across
	the screen. If the line width for the line segments is "nominal
	width" then the line does not appear on the screen. However if we
	explicitly state line width = 1 then everything is o.k, but takes
	longer in the benchmark to process, which does not delight our
	customer ( exceeding his time limit ).

	To run the program do the following : 

	  $ testv:==$mydir:testv
	  $ testv -l 10    This program should work fine and you will see 
			   the lines on the screen.
			   Depressing mb2 will cause the line width to change.

	  $ testv -l 200   This program will display junk or nothing on the 
			   screen as the line width is set to the nominal
			   line width. Depressing mb2 at this point will
	  		   cause the lines to appear after about 2 seconds
			   because the line width has now been explicitly
			   made > = 1.
			
	Please note when running testv -l 200 after testv -l 10 will sometimes
	display the lines correct, because it is using the pixmap from the 
	previous test and therefore everything looks fine. To see the true
	problem, depress MB2 once. Then depress mb2 again and you will see
	the lines cause the line width is now being explicitly stated.


	I would like to emphasize once again the urgency and importance
	of finding a solution to the problem ( other than explicitly setting
	the line width to 1 ) as the customer is one of Digital's largest
	and most important customers.

	Enclosed is a copy of the C source code.

	Thank you in advance for your assistance. We look forward
	to your speedy ( PLEASE ) reply.
						Doron Angel
------------------------------Cut here----------------------------------------

#include <stdio.h>
#include <decw$include/xlib.h>
#include <decw$include/xutil.h>

#define	WIDTH	    1200
#define HEIGHT	    900
#define X	    0
#define Y	    0

#define BLACK	    0
#define	RED	    1
#define BLUE	    2
#define WHITE	    3

#define DEPTH	    8

static char solid_list[]	=   {1,1};
static char dot_list[]		=   {1,6};
static char dot_dash_list[]	=   {1,6,4,6};
static char short_dash_list[]	=   {4,6};
static char long_dash_list[]	=   {8,6};
static char dash_list[]		=   {6,6};
static char short_dash_long_dash_list[]	=   {4,6,8,6};
static char three_dots_long_dash_list[]	=   {1,6,1,6,1,6,8,6};

typedef struct {
    int	     dash_size;
    char    *dash_list;
} DashType, *DashTypes;
#define dash_entry(list)    sizeof(list)/sizeof(list[0]), list

static DashType dashes[] = {
	{ dash_entry(solid_list)    },
	{ dash_entry(dot_list)	    },
	{ dash_entry(dot_dash_list) },
	{ dash_entry(short_dash_list) },
	{ dash_entry(long_dash_list) },
	{ dash_entry(dash_list) },
	{ dash_entry(short_dash_long_dash_list) },
	{ dash_entry(three_dots_long_dash_list) }
	};
static int  nDashes  = sizeof(dashes) / sizeof (dashes[0]);

static	char	*cap_names[] = {
		"CapNotLast",
		"CapButt",
		"CapRound",
		"CapProjecting"
	};
static	char	*join_names[] = {
		"JoinMiter",
		"JoinRound",
		"JoinBevel"
	};

static	Display *display;
static	Window	window;
static	Pixmap	pixmap;
static	GC	clearGC;
static	GC	defGC;
static	GC	dashGC;

static	int	cap = 0;
static  int	join= 0;
static	int	nLines = 10;
static	XPoint	*lines[16];


/*
**  Build Lines
*/
static BuildLines()
{
    register i,j;
    XPoint  *p;
    float   sx = ((float)(WIDTH-200)) / nLines;

    for (i=0; i<nDashes; i++) {
        lines[i] = p = calloc (nLines, sizeof(XPoint));
	for (j=0; j<nLines; j++, p++) {
	    p->x = j*sx  + 100;
	    p->y = i*100 +  50;
	}
    }    
}

/*
**  Draw The Lines on Expose Event
*/
static DrawLines( target, lw )
    Drawable	target;
    int		lw;
{
    register i;

    /*
    **	Clear the target
    */
    XFillRectangle(display,target,clearGC,0,0,WIDTH,HEIGHT);

    /*
    **	Draw Dashed lines with various dash patterns
    */
    XSetLineAttributes(display,dashGC,  lw,	LineOnOffDash,	cap, join);
    for (i=0; i<nDashes; i++) {
	XSetDashes(display,dashGC,
		    0,				/* Dash Offset	*/
		    dashes[i].dash_list,	/* Dash List	*/
		    dashes[i].dash_size);	/* Dash List size */
	XDrawLines (display,target,dashGC,
			lines[i], nLines, CoordModeOrigin);
    }
}

/*
**  Show Pixmap
*/
static	ShowPixmap()
{
    XClearWindow(display,window);
    XFlush(display);
}

/*
**  Create Window and its Pixmap of depth 8 for PseudoColor Visual
*/
static	CreateWindow(dpy)
    Display *dpy;
{
    Colormap	map;
    XVisualInfo	xvi;
    XSetWindowAttributes	wa;
    int				wa_flags;
    XColor	color;



    /*
    **	Find PseudoColor and Create Colormap
    */
    if (!XMatchVisualInfo(dpy,0,DEPTH,PseudoColor,&xvi)) {
	printf("Can't match PseudoColor Visual of Depth 8\n");
	exit(1);
    }

    map = XCreateColormap(dpy,DefaultRootWindow(dpy),xvi.visual,AllocAll);

    {
	XColor	color;
	/*
	**	SetUp Colormap
	*/
	color.flags = DoRed | DoGreen | DoBlue;

	/* Black */
	color.pixel = BLACK;
	color.red = color.green = color.blue = 0;
	XStoreColor(dpy,map,&color);
	/* Red   */
	color.pixel = RED;
	color.red = 0xFF00;
	color.green = color.blue = 0;
	XStoreColor(dpy,map,&color);
	/* Blue  */
	color.pixel = BLUE;
	color.blue  = 0xFF00;
	color.red = color.green = 0;
	XStoreColor(dpy,map,&color);
	/* White */
	color.pixel = WHITE;
	color.red = color.green = color.blue = 0xff00;    
	XStoreColor(dpy,map,&color);
    }    

    /*
    **	Create Pixmap
    */
    pixmap = XCreatePixmap(dpy, DefaultRootWindow(dpy),
				WIDTH, HEIGHT, DEPTH);

    /*
    **	Create the window
    */
    wa.background_pixmap = pixmap;
    wa.border_pixel	 = 0;
    wa.colormap		 = map;
    wa.event_mask	 = ButtonPressMask;

    wa_flags = CWBackPixmap | CWBorderPixel | CWColormap | CWEventMask;

    window = XCreateWindow(
		    dpy,    DefaultRootWindow(dpy),
		    X,	    Y,
		    WIDTH,  HEIGHT,
		    1,  DEPTH,	InputOutput, xvi.visual,
		    wa_flags,	&wa);

    /*
    **	Set Basic Parms in GC
    */
    clearGC = XCreateGC(display,window ,0,NULL);
    XSetState(display,clearGC, 0, 0, GXclear, AllPlanes);

    defGC  = XCreateGC(display,window,0,NULL);
    XSetState(display,defGC,	RED, BLUE, GXcopy, AllPlanes);

    dashGC = XCreateGC(display,window,0,NULL);
    XSetState(display,dashGC,	RED, BLUE, GXcopy, AllPlanes);

    /*
    **	Map the Window and Install Colormap
    */
    XMapWindow  (dpy,	window);
    XInstallColormap (dpy, map);

}

main(argc,argv)
	unsigned int argc;
	char *argv[];

{
    register	i;
    int	lineWidth = 0;
    XEvent	event;

    for (i=1; i<argc; i++) {
	if (!strcmp(argv[i],"-c")) {
	    cap = atoi(argv[++i]);
	    if (cap > 3) cap = 0;
	}
	else if (!strcmp(argv[i],"-j")) {
	    join = atoi(argv[++i]);
	    if (join > 2) join = 0;
	}
	else if (!strcmp(argv[i],"-l")) {
	    nLines = atoi(argv[++i]);
	}
    }
	    
    printf("Cap  style is %s\n",cap_names[cap]);
    printf("Join style is %s\n",join_names[join]);
    printf("Number of Lines %d\n",nLines);

    BuildLines(nLines);

    /*
    **	Open the display
    */
    if (!(display= XOpenDisplay(NULL))) {
	printf("Can't open the display");
	exit(1);
    }

    CreateWindow(display);

    while(1) {
	XNextEvent(display,&event);
	switch (event.type) {
	    case ButtonPress:
		if (event.xbutton.button == Button3)
		    exit(1);
		else if (event.xbutton.button == Button2) {
		    lib$init_timer();
		    DrawLines(pixmap, lineWidth);
		    ShowPixmap();
		    XSync(display,FALSE);
		    lib$show_timer();
		    printf("Line Width is %d\n",lineWidth);
		    lineWidth++;
		}
		break;
	    default:
		break;
	}
    }
}

    I do hope if it is as important a situation as you say, you are
    pursuing it via a CLD or other escalation means, and not relying on
    someone to read this conference.

>    I do hope if it is as important a situation as you say, you are
>    pursuing it via a CLD or other escalation means, and not relying on
>    someone to read this conference.


 The CLD will be issued only on the coming Sunday (weekend in Israel is on
Friday & Saturday). Since it is a non working in the U.S.A. on Sunday, and we
are celebrating Independance Day on coming monday, I hope some one the has seen
this problem before and his reply would have shorten things...

					*-Doron-*