Path: utzoo!utgpu!water!watmath!clyde!att!pacbell!ames!pasteur!agate!violet.berkeley.edu!pete
From: pete@violet.berkeley.edu (Pete Goodeve)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Custom Bit Maps & Intuition
Summary: Not so simple...
Message-ID: <10827@agate.BERKELEY.EDU>
Date: 12 Jun 88 03:14:42 GMT
References: <10628@agate.BERKELEY.EDU> <3958@cbmvax.UUCP> <1723@puff.cs.wisc.edu> <4370@gryphon.CTS.COM> <55567@sun.uucp> <AWfNOOy00VsNM6ukVB@andrew.cmu.edu> <3977@cbmvax.UUCP>
Sender: usenet@agate.BERKELEY.EDU
Organization: University of California, Berkeley
Lines: 66



Thanks for all your responses to my question, but I'm afraid the answer is
pretty much what I had expected: there ain't none!  No simple answer anyway.

I originally wrote <10628@agate.BERKELEY.EDU>:
-->
-->Okay, I have a simple goal (at least I thought it was...):  I want to put
-->up an Intuition screen containing a pre-generated custom bitmap,
-->uncluttered by title bar or other ornaments.
-->[]

The reason for this is that I want to have several bitmaps around (as many
as chip memory has space for) that I can pop up in a hurry.  They'll each
need their own custom screen because they may be of different resolutions
and depths.

The crux of the problem is at the OpenScreen(); here I can either:

a)  set CUSTOMBITMAP in the NewScreen structure, and give it a pointer to my
    (already filled) bitmap.

        ...in which case, before I can make any other call, Intuition
        instantly slaps a title bar (or the equivalent blank space if
        SCREENQUIET is also specified) across the top of my bit planes IN
        MEMORY.  It is then too late to recover the lost picture area.
        I can allocate the same bitmap to a window (as Aaron Avery in
        <1723@puff.cs.wisc.edu> suggested), but it does me no good, the
        pixels have been overwritten.

or

b)  not set CUSTOMBITMAP.

        ...in which case, equally instantly, Intuition allocates chip
        memory for bitplanes and a bitmap of the requested size.  It's true
        that I can then for instance open a borderless backdrop window
        without incurring any further penalty, but I can't use my original
        bitmap without either copying it or opening the window as
        SUPER_BITMAP.  Either way I have that superfluous, useless, bitmap
        hanging about, which I really don't want.



Only Mark Riley in article <4370@gryphon.CTS.COM> seems to have a solution:

 > I came up against the same problem when trying to display a picture
 > who's bitmap was already in memory.  I didn't want that and the
 > screen's bitmap to be in memory at the same time.  What I ended up
 > doing was blitting the top 11 rasters or so to a temporary area and
 > then blitting them back after I'd opened the screen with the
 > CUSTOMBITMAP and SCREENQUIET flags set.  A little extra code, but it
 > saves gobs of chip memory.  (So much for SCREENQUIET working like
 > it's supposed to, huh?  ;-)

I guess that's what I'll have to do.  I can think of one other possibility:
I could make each bitmap just enough bigger for the title bar ABOVE the
picture, then -- AFTER I've done OPenScreen() and ShowTitle(screen,FALSE)
-- I can adjust the screen's ViewPort vertical offset appropriately.
I think Mark's way is less work and space, though.  Thanks.

Actually, though I hate to suggest anything so crass, could this be
considered an Intution bug that ought to be fixed?  It should be possible
to have a custom bitmap left ENTIRELY alone.

                                            -- Pete --