Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!raybed2!hsd
From: hsd@raybed2.msd.ray.com (HERBERT DASILVA)
Newsgroups: comp.windows.x.motif
Subject: Re: bitmap
Keywords: bitmap pixmap image
Message-ID: <2228@raybed2.msd.ray.com>
Date: 22 Apr 91 15:01:28 GMT
References: <31@kivax.UUCP>
Organization: Raytheon Company, Tewksbury, Mass.
Lines: 85

In article <31@kivax.UUCP> koe@kivax.UUCP (Diana Koehler) writes:
>Hello,

>I have several bitmaps (created with a scanner) and I want to display 
>them within a Motif-Application.

  I'll explain this last...

>How does the bitmap have to be formatted, that it can be interpreted
>by Motif-applications.

  The bitmap should be in 'xbm' format.  This is the format output by
 the standard X11 tool 'bitmap'.

>(f.e Some times ago I have seen the picture of a mandrill. I think
>     that the bitmap is NOT created with the bitmap editor "bitmap".)

  The mandrill is NOT a bitmap, it is a PIXMAP.  A bitmap is just that,
 a two dimensional 'map' (read array) of bits (1s and 0s, on and off).
 A pixmap has color data encoded at each pixel location in the 'map'.

>Does there exist an other tool for creating bitmaps?

  Probably, but I don't know of any off hand.

>Any help would be apreciate.
>Thanks in advance

>Diana

  To display a bitmap in a Motif application is pretty easy, you display it
in an XmLabel (or XmLabelGadget) like this:

  Since bitmaps contain no color, you must choose two colors, a foreground and
a background color.  You do this by allocating the colors:

Display *display;

XColor *bgColor;      /* Actual color values for the color requested */
XColor *fgColor;

XColor *bgScreenColor;  /* Closest color the display can actually produce */
XColor *fgScreenColor;

  bgColor = (XColor *)malloc( sizeof( XColor ) );
  fgColor = (XColor *)malloc( sizeof( XColor ) );

  bgScreenColor = (XColor *)malloc( sizeof( XColor ) );
  fgScreenColor = (XColor *)malloc( sizeof( XColor ) );

  display = XtDisplay( widget );
  sts = 
    XLookupColor( display, DefaultColormap( display, DefaultScreen(display) ),
	          "black", bgColor, bgScreenColor );
  sts = 
    XLookupColor( display, DefaultColormap( display, DefaultScreen(display) ),
	          "white", fgColor, fgScreenColor );
  free( bgColor );
  free( fgColor );

Then create a pixmap from the 'xbm' bitmap file:

Pixmap pixmap;

  pixmap = XmGetPixmap( XtScreen(widget), "/usr/your/path/bitmap.xbm", 
                        fgScreenColor->pixel, bgScreenColor->pixel );
  free( fgScreenColor );
  free( bgScreenColor );


Then create the label with the pixmap in it:

  ac = 0;
  XtSetArg( args[ac], XmNlabelType, XmPIXMAP );  ac++;
  XtSetArg( args[ac], XmNlabelPixmap, pixmap );  ac++;
  pixWidget = XmCreateLabel( parent, "LabelPixmap", args, ac );
  XtManageChild( pixWidget );


Ta Da!  Instant bitmap.  A Truly Impressive addition to any program.


	Any questions or problems, don't hesitate to ask.

	Herb DaSilva