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Very Large Bitmap Experiment

In recent weeks several posts in the newsgroups were about
problems caused by fearless programmers creating bitmaps
of unusually large dimensions.

To quantify the size of the largest "legal" bitmap -- a compound
limitation of the video adapter, Windows, and who knows what
else --  I developed a program that can be used to manually
find the largest pf24bit that can be created on a given machine.

Find the program and some preliminary results at
http://www.efg2.com/lab/Graphics/VeryLargeBitmap.htm
(Perhaps I should automate the program with a binary
search to find the largest bitmap automatically.)

If the largest bitmap on your system is unusually large
-- or small -- please let me know so I can update the
summary table in this Lab Report.  (Don't bother
reporting results in the general range already shown
in the table.)

If there is enough interest, perhaps I should extend the test
to other PixelFormats (probably pf1bit and pf8bit).

In addition to creating a very large bitmap, the program
actually has an algorithm for counting all the unique
RGB colors in a bitmap (assuming you can't create
a pf24bit bitmap bigger than 4096-by-4096 each
pixel is given a unique RGB color triple).

I'll try to respond to any questions or comments about this
program, but I can sometimes be days (weeks?) behind in
responding to E-mail.

efg
_________________________________
efg's Computer Lab:  http://www.efg2.com/lab
Delphi Books:  http://www.efg2.com/lab/TechBooks/Delphi.htm

Earl F. Glynn     E-Mail:  EarlGl...@att.net
Overland Park, KS  USA

 

Re:Very Large Bitmap Experiment


Quote
Earl F. Glynn wrote:

> In recent weeks several posts in the newsgroups were about
> problems caused by fearless programmers creating bitmaps
> of unusually large dimensions.

> To quantify the size of the largest "legal" bitmap -- a compound
> limitation of the video adapter, Windows, and who knows what
> else --  I developed a program that can be used to manually
> find the largest pf24bit that can be created on a given machine.

Why not just read the microsoft article that explains
the limitation and live with it? I'm sure you have read
some of my posts that sum it up as:

1) Don't create DDB's that are larger than the screen.

2) Don't create/blt DDB's from a DIB, were the memory
consumption of the source rectangle exceeds the memory
consumption of the screen.

3) Get around the above limitation by

a) to make large DDB;s, tile screen sized bitmaps.

b) Instead of using functions like CreateDIBitmap(),
make the bitmap(s) and blt the DIB.

c) Blt DIB's in screen_sized or smaller chunks
being carefull not to exceed screen memory requirments.

Joe [please practice safe blts]
--
%Z%------(-  
%H%------(-

Re:Very Large Bitmap Experiment


In article <3771D376.2...@badsector.com>,

Quote
  zeppinh...@badsector.com wrote:

[...]

> Joe [please practice safe blts]
> --
> %Z%------(-
> %H%------(-

    Huh, so Zeppin Hood really is Joe Hecht (last time I saw
something from ZH, long ago, he was talking about Joe as though
they were different people - someone seemed to think ZH was
JH but I couldn't tell why he thought so.) Huh.

Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.

Re:Very Large Bitmap Experiment


Quote
"David C. Ullrich" wrote:

> In article <3771D376.2...@badsector.com>,
>   zeppinh...@badsector.com wrote:

> [...]

> > Joe [please practice safe blts]
> > --
> > %Z%------(-
> > %H%------(-

>     Huh, so Zeppin Hood really is Joe Hecht (last time I saw
> something from ZH, long ago, he was talking about Joe as though
> they were different people - someone seemed to think ZH was
> JH but I couldn't tell why he thought so.) Huh.

I think it was me who noticed that ZH = JH. Tip-offs are all Led
Zeppelin-related: The name, obviously, but also the Gibson SG
double-neck in the .sig, similar to the model played by Jimmy Page. (I
poked around Joe's site once, and noticed that he was a big Page fan.
No, I'm not stalking you, Joe.)

Preferring Fenders,

Dave
--
http://www.csd.net/~daves

Re:Very Large Bitmap Experiment


Quote
ZeppinHood <zeppinh...@badsector.com> wrote in message

news:3771D376.2DD5@badsector.com...

Quote
> Why not just read the microsoft article that explains
> the limitation and live with it?

Well, there's can be a difference between "theory" and "practice."
Just call me a "doubting Thomas."

A guy in Denmark has already reported he can create a 6272-by-6272
pf24bit bitmap (DIB) under the Windows 2000 Beta.  I only have limited
access to NT machines, and some of these limitations appear to be
different under NT.  (I need more data points.)

The guy in Europe actually created a pf24bit bitmap with every possible
color -- which was my goal when I wrote my color counter.  (If the truth
be known, I was originally trying to boundary test my color counter,
not just create large bitmaps.)

And there are enigmas all over the place:  my older and less capable
Dell machine can create a much larger bitmap (DIB) than my newer, faster,
more capable Dell -- doesn't really make sense.

Quote
> I'm sure you have read
> some of my posts that sum it up as:

You're right.  BTW, I'll put your summary as a postscript in the Lab Report.
I gave you full credit, but should I have said "Joe" or "ZeppinHood?"
(For now, I said both).

Besides, David now knows who ZeppinHood is!

efg
_________________________________
efg's Computer Lab:  http://www.efg2.com/lab
Delphi Books:  http://www.efg2.com/lab/TechBooks/Delphi.htm

Earl F. Glynn     E-Mail:  EarlGl...@att.net
Overland Park, KS  USA

Re:Very Large Bitmap Experiment


Quote
Dave Shapiro wrote:

> "David C. Ullrich" wrote:

> > In article <3771D376.2...@badsector.com>,
> >   zeppinh...@badsector.com wrote:

> > [...]

> > > Joe [please practice safe blts]
> > > --
> > > %Z%------(-
> > > %H%------(-

> >     Huh, so Zeppin Hood really is Joe Hecht (last time I saw
> > something from ZH, long ago, he was talking about Joe as though
> > they were different people - someone seemed to think ZH was
> > JH but I couldn't tell why he thought so.) Huh.

> I think it was me who noticed that ZH = JH. Tip-offs are all Led
> Zeppelin-related: The name, obviously, but also the Gibson SG
> double-neck in the .sig, similar to the model played by Jimmy Page. (I
> poked around Joe's site once, and noticed that he was a big Page fan.
> No, I'm not stalking you, Joe.)

> Preferring Fenders,

Hey Dave!

I think I need to get me a couple of Fenders! I have been
having lots of fun with a set of Ovations lately, and dont
remember the last time I even dusted off the doubleneck.
Let me know when you get some banjo stuff on your web page,
as my banjo version of Stairway is getting a little old :)

ZH
--
 %% %%
 %% %%
 %% %%
 || ||
 || ||
 || ||   %Z%------(-  
 || ||   %H%------(-
{~Z~H~}  

Quote
}|| ||{  

{|| ||}  The "double-neck" mark of ZeppinHood's sword
 ~~~~~   --------------------------------------------
****************************
*Who was that masked idiot?*
***  ***********************
  * *
   *
  ;)

Re:Very Large Bitmap Experiment


Quote
Earl F. Glynn wrote:
> I gave you full credit, but should I have said "Joe" or "ZeppinHood?"
> (For now, I said both).

Thanks Earl! I truly do like both :)

ZH
--
 %% %%
 %% %%
 %% %%
 || ||
 || ||
 || ||   %Z%------(-  
 || ||   %H%------(-
{~Z~H~}  

Quote
}|| ||{  

{|| ||}  The "double-neck" mark of ZeppinHood's sword
 ~~~~~   --------------------------------------------
****************************
*Who was that masked idiot?*
***  ***********************
  * *
   *
  ;)

Re:Very Large Bitmap Experiment


Quote
ZeppinHood wrote:
> Hey Dave!

> I think I need to get me a couple of Fenders! I have been
> having lots of fun with a set of Ovations lately, and dont
> remember the last time I even dusted off the doubleneck.
> Let me know when you get some banjo stuff on your web page,
> as my banjo version of Stairway is getting a little old :)

The banjo stuff is currently taking a back seat to steel and guitar
stuff. My recommendation: Get a Telecaster and a Chet Atkins album. I
just started tabbing "Blue Angel". Amazing guitar.

Dave

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