Conference bulova::decw_jan-89_to_nov-90

Probably because there's a visual depth mismatch.  On a monochrome system,
everything is going to have a depth of 1.  On a color system, bitmaps still
have a depth of 1, but the default visual depth is 8.  You didn't show us the
pixmap and gc parameters, so it's hard to tell from your code fragment.
The fact that your XCreateImage call says XYBitmap rather than XYPixmap format
is suspicious.

--PSW

    Re: -1
    
    I have
    	gc.foreground = BlackPixelOfScreen(...
    	gc.background = WhitePixelOfScreen(...
    
    How does X treat the 1's and 0's in a Bitmap/Pixmap? If I specify
    XYPixmap in the XCreateImage call, I got the image printed in reverse
    video. Why?
    
    Thanx
    
    -Terry

If you specify XYPixmap, the bits you give it are copied into the pixmap.  If
you say XYBitmap, the bits you pass in are used as selectors.  A 1 will put
the foreground color into the pixmap; a 0 will put the background color.

Note that you can do a PutImage of a 1-bit deep image into a multi-deep pixmap
that way.  In fact, the image you specify *must* be 1 deep for XYBitmap.

Burns

    1) When I create a Pixmap, will all the planes be automatically filled
       up with 0's?
    2) A XYPixmap's 0 means black and a XYBitmap's 0 means background
       color?
    3) What happens if I XCreateImage with depth > 1 and the image data
       only has depth 1?
    4) What happens if I XPutImage such an image into a Pixmap of depth >
       1?
    
    Thanx a lot
    
    -Terry

>    1) When I create a Pixmap, will all the planes be automatically filled
>       up with 0's?

	"The initial contents of the pixmap are undefined." (page 93)

>    2) A XYPixmap's 0 means black and a XYBitmap's 0 means background
>       color?

	Neither.  I think it just means "0", the value of which depends
	on the colormap used when the pixmap is displayed.

I'm not sure about (3) and (4), but I'm sure the answers are somewhere in
"X Window System" (Scheifler, et. al.).  If you don't have this book,
you should go out TODAY and get it!

-steve-

    2) A XYPixmap's 0 means black and a XYBitmap's 0 means background
       color?
    
    ***Steve is right about XYPixmap.  0 means display a pixel value of 0.
    ***This may be black, but don't count on it.  You HAVE to have any
    ***pixel values you use defined in the colormap.
    ***You are correct about XYBitmap's 0 meaning background.
    
    3) What happens if I XCreateImage with depth > 1 and the image data
       only has depth 1?
    
    ***XCreateImage is a routine which creates a data structure which
    describes the image data.  If you tell it depth >1 and the data is
    really only 1, you have a broken descriptor.  X will act as though
    the data is deep, but since it is not, you will probably get a mush
    of garbage on the screen (if anything).
    4) What happens if I XPutImage such an image into a Pixmap of depth >
       1?
    ****See .3.
    
    ****Burns
    

    Could you guys give me detail about the book? Like which publisher,
    what edition, and what order number?
    
    Thanx
    
    -Terry

I am sitting at home so I don't have the order number but, the book is

The X Window System - C Language Reference and Protocol Manual
Scheifler, Gettys and Newman
Digital Press

Since we publish it, you can get a really cheap price internally.  If you
need it quick you may have to buy it from a bookstore (perhaps at a local
university).

This is the big maroon, paperback book with the X logo on the cover.  The
authors were the original developers of X (Scheifler is still with the X
Consortium). It is therefore quite authoritative.

Dick

  X Window System: C Library and Protocol Reference
  Digital Press
  Order Number : EY-6737E-DP
  ISBN : 1-55558-012-2

  About $27.50 + tax for Digital employees.


  Another highly recommended book is

  "Introduction to the X Window System"
  Oliver Jones
  Prentice-Hall
  ISBN : 0-13-499997-5


						-=> Jim <=-

    Sorry, but one more question. How can I order it? Can I order it by
    EMail?
    
    -Terry

  I'm not sure about E-mail.  I just sent them a check and they sent me the
book.  I bought it as a Digital employee and not a cost center.

  You will probably need to call them to find out the current price of the
book.  Since you are a Digital employee, you get the book for 50% of the
cover price.  The tax you add depends on your locale.  Here in Colorado
Springs the tax is 6.7%, so this is what I had to add to the price of the
book.

  I apologize, but I don't have their number or address handy.  Maybe someone
else does.

  If you can get your cost center to buy the book, then the procedure is the
same as ordering any documentation.  This way, however, seems to take longer.
I received my book in about 10 days via UPS after placement of order.

As for the "Introduction to..." book, any _good_ bookstore should either have
it or can order it for you.  I think's it's price was somewhere between $25
and $30.

						-=> Jim <=-