WALLPAPR Windows Wall Paper Changer Utility

Just what you need is another wall paper changer, right?  There must be
100's of these things on CompuServe. So, why did I write another one?
Well, for one thing, WallPapr is NOT like the myriad of other programs.
It is NOT intended to automatically change your wall paper at timed
intervals.

Rather, WallPapr is designed to replace the limited function which is part
of Control Panel's Desktop app with something a little more elegant and
user friendly.

WallPapr is an interactive utility.  That is, it allows you to search any
directory on any drive on your PC and display a thumbnail sketch of the
graphic you are thinking of using as wall paper.  Unlike Desktop, the
pictures do NOT have to be in the Windows or System subdirectory.  Also
unlike Desktop, you are not limited to just BMP (uncompressed bitmap)
files. WallPapr also lets you use RLE (Run Length Encoded compressed
bitmaps) as wall paper.

Of course, WallPapr lets you tile your picture. And, you can even delete
your existing wall paper.

Operation

When WallPapr launches, it displays the current wall paper picture as a
thumbnail (or a blank picture if you don't have any defined). Then, using
Visual Basic's Common Dialog File Open VBX, you can choose any bitmap
and ready it for use as wall paper.  In case you change your mind, you can
continue to select new pictures until you say "OK - change my wall paper!".

Limitations

WallPapr requires VBRUN300.DLL, CMDIALOG.VBX, and COMMDLG.DLL (which is
usually already installed by Windows).  These files are not included in
the archive.

One possible limitation is the use of 24-bit (16 million) color pictures.
I'm told that Visual Basic is not designed to use pictures with more than
256 colors. I don't know if that is true or not, but I can tell you the
experience I have had.

WallPapr uses LoadPicture to display the thumbnail sketch graphic.  On my
PC, which has a Cirrus Logic chip graphics card, if the number of colors
is set to less than 65,535 (64K), 16 million color images take a LONG time
to load; sometimes several minutes.  As near as I can tell, this is a
combination of my dumb video drivers and the way that LoadPicture works
(which is a Microsoft trade secret; I can't find any docs on it anywhere).

I know that 16 million color pictures can be displayed fast when my video
card is set to 256 colors, but I imagine that's because the programmers
of the commercial graphics applications are both smarter than me and are
using C as their programming language.

Anyway, WallPapr warns you when it "sees" a 16 million color picture and
asks if you want to continue even if it takes forever.  Maybe this isn't
a problem with other video cards.

If you discover a neater way to do the graphics loads other than with
VB's LoadPicture, PLEASE drop me an E-mail note and tell me how you did it.

Another limitation, which isn't my code, appears VERY rarely with RLE files.
So far, I have only seen it with 16-color RLE's.  If you encounter a "bad"
file, it will cause a GPF and most likely abort WallPapr.  Again, I think
this is a Cirrus Logic "brain dead" driver problem (or so I've been
advised).  What is interesting is that program's like Paint Shop Pro
(which can also create RLE's) can display these "bad" files just fine, but
WallPapr blows up.  In one case, Windows refused to start when a "bad"
16-color RLE had been set as the wall paper.  So, be forewarned!


I hope you enjoy using this program and find it as useful as I have.  It is
totally free, but it is NOT public domain (i.e., it is copyrighted by me).
Oh, one more thing: I have absolutely no liability for anything you do
with my program or any damage it might cause you should there be a bug.



                        						         Jerry Rivers
						                                 January 22, 1995

