Conference bulova::decw_jan-89_to_nov-90

Randy -

you're close... First off, you're right - there is no direct relationship
between the charset and fonts -- that list is the best you'll get.  (I am
told that there is a proposal to get the charsets and fonts matched up...)

The 1st number is the pixel size, the second is the point size (devide by
ten).  So the font you mention in #1 is an 8 point font.  (For a complete
description of the FontName syntax, see section 10.2 in the Font memo in the
next reply).

I have included a test driver that demonstrates how to set a font...

Jay


#ifdef VMS
#include "decw$include:decwdwtwidgetprog.h"
#else
#include "/usr/include/X11/DECwDwtWidgetProg.h"
#endif
#include <decw$include/cda$def.h>


XFontStruct  *x_font_list;
DwtFontList  good_font_list;



/* Command line options table.  Only resources are entered here...there is a
   pass over the remaining options after XtParseCommand is let loose. */

static XrmOptionDescRec options[] = {
{"-label",	XtNlabel,	XrmoptionSepArg,	NULL}
};


/*
 * Report the syntax for calling xlabel
 */
Syntax(call)
	char *call;
{
}

static Widget textwid;

static Widget toplevel, create_fs_pb, change_fs_pb, exit_fs_pb, work, mainw;

static void bye_bye()
{

    exit(1); 

}

static DwtCallback bye_bye_cb[2] = 
{
    {(VoidProc) bye_bye, NULL},
    {NULL, NULL}
};




static void ChangeAttributes()
{

    Arg   al[10];
    int	  ac = 0;

    x_font_list = XLoadQueryFont(XtDisplay(mainw), 
                  "-*-Courier-BOLD-R-Normal--*-120-*-*-M-*-*-*");
   
    good_font_list = DwtCreateFontList(x_font_list, CDA$K_ISO_LATIN8);

    XtSetArg(al[ac], DwtNfont, good_font_list);
    ac++;
    XtSetValues(textwid, al, ac);
}



static DwtCallback change_cb[2] = 
{
    {(VoidProc) ChangeAttributes, NULL},
    {NULL, NULL}
};

static void manage()
{
    XtManageChild(textwid);
};

static DwtCallback manage_cb[2] = 
{
    {(VoidProc) manage, NULL},
    {NULL, NULL}
};


static void unmanage()
{
    XtUnmanageChild(textwid);
};

static DwtCallback unmanage_cb[2] = 
{
    {(VoidProc) unmanage, NULL},
    {NULL, NULL}
};

int main(argc, argv)
    unsigned int argc;
    char **argv;
{
    Arg    arglist[20];
    int    argCount = 0;
    char   *dirmask, *value;
    int *dpy;

    {
	char c[6];
	int i;

	sscanf("1234$","%d",&i);
	sprintf(c,"%d",12345);
    }

    toplevel = XtInitialize(
	argv[0], "XLabel",
	options, 1, &argc, argv);

    DwtSetArg("TRUE",arglist,0,XtNallowShellResize);
    XtSetValues(toplevel,arglist,1);

    mainw = DwtMainWindow(toplevel,"main",0,0,300,300);
    XtManageChild(mainw);    

    work = DwtDialogBoxCreate(mainw,"work",NULL,0);
    XtManageChild(work);    

    create_fs_pb = DwtPushButton(work,
			       "create fs pb",
			       20,20,
			       DwtLatin1String("manage fs widget"),
			       manage_cb,NULL);
    XtManageChild(create_fs_pb);
    
    change_fs_pb = DwtPushButton(work,
			       "change fs pb",
			       20,40,
			       DwtLatin1String("change fs widget"),
			       change_cb,NULL);
    XtManageChild(change_fs_pb);
    
    exit_fs_pb = DwtPushButton(work,
			       "exit fs pb",
			       20,60,
			       DwtLatin1String("exit"),
			       bye_bye_cb,NULL);
    XtManageChild(exit_fs_pb);
    

    XtSetArg(arglist[argCount], DwtNx, 20);
    argCount++;
    XtSetArg(arglist[argCount], DwtNy, 80);
    argCount++;
    XtSetArg(arglist[argCount], DwtNrows, 1);
    argCount++;
    XtSetArg(arglist[argCount], DwtNcols, 25);
    argCount++;
/* 
    XtSetArg(arglist[argCount], DwtNfont, (fs->dialog.fontlist + 0) );
    argCount++;
*/ 
    textwid = DwtSTextCreate( work,
			      "Test TextWidget",
			      arglist, 
			      argCount);
    XtManageChild(textwid);


    DwtMainSetAreas (mainw, NULL, work, 0, 0, 0);

    XtRealizeWidget(toplevel);

    dpy = DwtGetDisplay(toplevel);
    XSynchronize(dpy, TRUE);

    XtMainLoop();

    /* UNREACHABLE */
    return (0);
}
    

  font name syntax:

  FOUNDRY, FAMILY_NAME, WEIGHT_NAME, SLANT, SETWIDTH_NAME, ADD_STYLE_NAME,
  PIXEL_SIZE, POINT_SIZE, RESOLUTION_X, RESOLUTION_Y, SPACING, AVERAGE_WIDTH,
  CHARSET_REGISTRY, CHARSET_ENCODING, FONT_ASCENT, FONT_DESCENT, CAP_HEIGHT,
  FACE_NAME, COPYRIGHT, NOTICE


    

    Thanks very much - I really appreciate the help!

    The following works fine (knowing that dpi = 75) but I'm confused 
    still by what charset is and how it doesn't seem to have any
    effect in the sequence below.  I've patched in charset = 1,2,3,32
    and still get what looks like whatever font is named in fontlist[0].

    fontlist = XListFonts( display,
                           "-Adobe-Helvetica-Medium-R-Normal--10-100-75-75-P-56-ISO8859-1",
		           2, &nfonts );

    pfont = XLoadQueryFont( display, fontlist[0] );  
    
    font_list = DwtCreateFontList( pfont, charset ); 
>>>                                       -------
    XtSetArg( arg_list[arg_count], DwtNfont, font_list );

    XtSetValues( menu, arg_list, arg_count );

Randy

 >  The following works fine (knowing that dpi = 75) but I'm confused 
 >   still by what charset is and how it doesn't seem to have any
 >   effect in the sequence below.  I've patched in charset = 1,2,3,32
 
The "charset" you pass to DwtCreateFontList must be one of the character
set constants out of SYS$LIBRARY:CDA$DEF.H.  If you look in that file you
will also see the relationship between the charset ids and the names 
at the end of the font names.

For example:

#define CDA$K_ISO_LATIN1 1		/* ISO Latin 1 (ISO 8859-1)   */

           ^             ^                                 ^
         name         number                      looks like name at end of
                                                  font that goes with it.

The reason it is working no matter what you put in there, is that if the
toolkit can't find a "match" in the fontlist, it uses the first entry
in the fontlist (and your fontlist only contains 1 entry...).

Leo

Reply to .4 

Thsnks for the info about default selection from fontlist if charset does
not have a match.  

Is that a guaranteed functionality - if so - then is it safe to assume that
charset = -1 (say) will *never* match and will force the selection from 
fontlist.  How about in this case an appropriate definition of CDA$K_* which 
will do this?

It's also still not clear to me how the "match" is done (from the point of 
view of CDA$DEF.H).  With the names I get back from XListFonts, and 
the naming conventions described in note 620.4, it looks as if many fonts 
can match the typical /* comment font description */.  I'm concerned about 
possible matching changes and an application ending up with a different font.

Randy

> Is that a guaranteed functionality - if so - then is it safe to assume that
> charset = -1 (say) will *never* match and will force the selection from 
> fontlist.  How about in this case an appropriate definition of CDA$K_* which 
> will do this?

No, it's not guaranteed.  I was merely explaining to you why it was behaving the
way it was.

> It's also still not clear to me how the "match" is done (from the point of 
> view of CDA$DEF.H).  With the names I get back from XListFonts, and 
> the naming conventions described in note 620.4, it looks as if many fonts 
> can match the typical /* comment font description */.  I'm concerned about 
> possible matching changes and an application ending up with a different font.

The toolkit is not doing any automatic matching for you.  The CDA$K_* constants
appear both in the compound string and the font list.  That is all the
toolkit "matches".  It doesn't look at the logical font name at all.
It's up to the application to ensure that the right font is in the font list
associated with the right CDA$K_* constant.

Leo

Is it true that an SText widget must be managed and realized before its
font can be changed?  I am getting an error at the XtSetValues call in the
code below.  If I move the XtManageChild to before the XtSetValues it seems
to work.

Sue

******************************************************************************

void popup_stext (Widget parent, int x, int y)
{
   XFontStruct *font;
   DwtFontList font_list;
   Arg al[20];
   int ac=0;

   popup = DwtSText (
	    parent,		    		/* parent widget */
	    "",					/* no name */
	    x, y,				/* location */
            15,					/* columns */
            1,					/* rows */
	    "");				/* initial string value */

   font = XLoadQueryFont (dpy, "-Adobe-Courier-Medium-R-Normal--12-120*");
   font_list = DwtCreateFontList (font, CDA$K_ISO_LATIN8); 

   XtSetArg (al[ac], DwtNfont, font_list); 		ac++;
   XtSetValues (popup, al, ac);

   XtManageChild (popup);
}